Fermentation

16 pages, 3104 KiB

Open AccessArticle

Halophytes as Feedstock for Biogas Production: Composition Analysis and Biomethane Potential of Salicornia spp. Plant Material from Hydroponic and Seawater Irrigation Systems

by Aadila Cayenne, Ariel E. Turcios, Mette Hedegaard Thomsen, Rui Miranda Rocha, Jutta Papenbrock and Hinrich Uellendahl

Fermentation 2022, 8(4), 189; https://doi.org/10.3390/fermentation8040189 - 18 Apr 2022

Cited by 7 | Viewed by 3309

Abstract

The halophyte plant species Salicornia europaea and Salicornia ramosissima were investigated for their potential to serve as a substrate for biogas production. Salicornia europaea was cultivated in hydroponic systems under varying salt concentrations (0, 10, 20, and 30 g/L NaCl), while S. ramosissima [...] Read more.

The halophyte plant species Salicornia europaea and Salicornia ramosissima were investigated for their potential to serve as a substrate for biogas production. Salicornia europaea was cultivated in hydroponic systems under varying salt concentrations (0, 10, 20, and 30 g/L NaCl), while S. ramosissima was grown in greenhouse farming with aquaculture effluent irrigation. The biomethane potential of the two halophyte feedstocks was determined through batch experiments, and correlations to the plant biochemical composition were investigated. Ash and mineral content of S. europaea was correlated to the increasing salt concentration used for plant cultivation in hydroponic systems. No indication of inhibition of the anaerobic digestion process was detected for sodium concentrations of up to 2400 mg/L in the anaerobic batch-test assays. The highest biomethane yield of S. europaea of 250 mL CH₄/gVS was obtained when grown under 20 g/L NaCl and up to 300 mL CH₄/gVS for S. ramosissima. By concentrating the dry matter content, the biomethane yield per ton of feedstock could be increased from 24 m³ CH₄/t of the fresh halophyte plant to 74 m³ CH₄/t by fractionation into a pulp fraction and to 149 m³ CH₄/t by drying of the plant at room temperature for 1 week. Full article

(This article belongs to the Special Issue New Research on Anaerobic Digestion)

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15 pages, 2340 KiB

Open AccessArticle

Enhanced Phenazine-1-Carboxamide Production in Pseudomonas chlororaphis H5△fleQ△relA through Fermentation Optimization

by Jiajia Cui, Wei Wang, Hongbo Hu, Hongyan Zhang and Xuehong Zhang

Fermentation 2022, 8(4), 188; https://doi.org/10.3390/fermentation8040188 - 18 Apr 2022

Cited by 5 | Viewed by 2836

Abstract

Phenazine-1-carboxamide (PCN) is effective to control many plant pathogens, and improving PCN production would be of great significance in promoting its development as a biopesticide. This study was conducted to improve the PCN production of Pseudomonas chlororaphis H5△fleQ△relA through fermentation [...] Read more.

Phenazine-1-carboxamide (PCN) is effective to control many plant pathogens, and improving PCN production would be of great significance in promoting its development as a biopesticide. This study was conducted to improve the PCN production of Pseudomonas chlororaphis H5△fleQ△relA through fermentation optimization in both shake flask and bioreactor. The PCN production of H5△fleQ△relA was improved from 2.75 ± 0.23 g/L to 5.51 ± 0.17 g/L by medium optimization in shake flask using Plackett-Burman design, the path of steepest ascent experiment and central composite design. Then, PCN production reached 8.58 ± 0.25 g/L through optimizing pH in 1 L bioreactor. After pH optimization, the transcriptional levels of ccoO_2 and ccoQ_2 genes related to microbial aerobic respiration were significantly upregulated, and the relative abundance of 3-oxo-C14-HSL was significantly enhanced 15-fold, and these changes were vital for cell activity and metabolites production. Furthermore, the PCN production reached 9.58 ± 0.57 g/L after optimization of the fed-batch fermentation strategy in 1 L bioreactor. Finally, the fermentation scale-up of the optimal medium and optimal feeding strategy were conducted in 30 L bioreactor at the optimal pH, and their PCN production reached 9.17 g/L and 9.62 g/L respectively, which were comparable to that in 1 L bioreactor. In this study, the high PCN production was achieved from the shake-flask fermentation to 30 L bioreactor, and the optimal feeding strategy improved PCN production in bioreactor without increasing total glycerol compared with in shake flask. It provides promising pathways for the optimization of processes for the production of other phenazines. Full article

(This article belongs to the Topic Bioreactors: Control, Optimization and Applications)

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13 pages, 1217 KiB

Open AccessArticle

Functional, Physicochemical, Rheological, Microbiological, and Organoleptic Properties of Synbiotic Ice Cream Produced from Camel Milk Using Black Rice Powder and Lactobacillus acidophilus LA-5

by Wael F. Elkot, Ateteallah H. Ateteallah, Maalem H. Al-Moalem, Magdy Ramadan Shahein, Mohamed A. Alblihed, Walied Abdo and Ehab Kotb Elmahallawy

Fermentation 2022, 8(4), 187; https://doi.org/10.3390/fermentation8040187 - 15 Apr 2022

Cited by 29 | Viewed by 4513

Abstract

Camel milk has become more popular among customers in recent years as a result of its therapeutic effects. In many parts of the world, it is considered one of the primary components of human nutrition. The present study aimed to develop a novel [...] Read more.

Camel milk has become more popular among customers in recent years as a result of its therapeutic effects. In many parts of the world, it is considered one of the primary components of human nutrition. The present study aimed to develop a novel synbiotic ice cream from camel milk formulated with black rice powder (BRP) and investigate the viability of probiotic bacteria (Lactobacillus acidophilus LA-5) during the storage period (60 days). Skim milk powder was replaced by BRP at levels of 0, 25, 50, and 75%. The produced ice cream was examined for some physicochemical, rheological, microbiological, and sensorial properties. The obtained results indicated that the incorporation of BRP into ice cream blends resulted in significant increases in the overrun, viscosity, and melting resistance of ice cream samples (p < 0.05). However, the freezing point decreased with increasing the proportion of BRP in the blend. The sensory evaluation results showed that the most acceptable treatments were those formulated with 25% and could be increased to 50% of BRP with no significant differences. The incorporation of BRP improved the viability of Lactobacillus acidophilus LA-5 in ice cream samples over 60 days of storage. Collectively, a synbiotic camel milk ice cream formulated with black rice powder was produced that, in turn, enhanced the physicochemical and rheological properties of ice cream samples and produced a significant protective effect on the viability of probiotic bacteria. Full article

(This article belongs to the Special Issue Dairy Fermentation)

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15 pages, 3842 KiB

Open AccessArticle

Cultivation of Microalgae in Unsterile Malting Effluent for Biomass Production and Lipid Productivity Improvement

by Janak Raj Khatiwada, Haipeng Guo, Sarita Shrestha, Chonlong Chio, Xuatong Chen, Aristide Laurel Mokale Kognou and Wensheng Qin

Fermentation 2022, 8(4), 186; https://doi.org/10.3390/fermentation8040186 - 14 Apr 2022

Cited by 10 | Viewed by 3330

Abstract

Microalgae have the potential to grow in nutrient-rich environments and have the ability to accumulate nutrients from wastewater. The nutrients in malting wastewater are ideal for microalgae cultivation. However, there is limited published work on the growth characteristics of freshwater microalgae grown in [...] Read more.

Microalgae have the potential to grow in nutrient-rich environments and have the ability to accumulate nutrients from wastewater. The nutrients in malting wastewater are ideal for microalgae cultivation. However, there is limited published work on the growth characteristics of freshwater microalgae grown in malting effluent. This study examined the potential of diluted malting effluent for the growth of freshwater green algae Chlorella sp. and Chlamydomonas sp. isolated from northern Ontario and subsequent biomass and lipid production. Under the 18:6 h light/dark cultivation cycle, the highest cell number counted (540 × 10⁴ cell·mL⁻¹ on day 20) and total chlorophyll content were found in 50% diluted malting effluents for Chlorella sp., whereas the 70% dilution concentration was the most productive for Chlamydomonas (386 × 10⁴ cell·mL⁻¹ on day 16). The total lipid content was higher in the 50% dilution concentration of malting effluent in both Chlorella sp. (maximum 20.5%–minimum 11.5% of dry weight) and Chlamydomonas sp. (max 39.3%–min 25.9% of dry weight). These results emphasize the suitability of using unsterile diluted malting effluent for microalgae cultivation. Full article

(This article belongs to the Special Issue Recent Trends in Biogenic Gas, Waste and Wastewater Fermentation)

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12 pages, 312 KiB

Open AccessReview

The Technological Perspectives of Kombucha and Its Implications for Production

by Ícaro Alves Cavalcante Leite de Oliveira, Victória Ananias de Oliveira Rolim, Roberta Paulino Lopes Gaspar, Daniel Quarentei Rossini, Rayane de Souza and Cristina Stewart Bittencourt Bogsan

Fermentation 2022, 8(4), 185; https://doi.org/10.3390/fermentation8040185 - 13 Apr 2022

Cited by 26 | Viewed by 7312

Abstract

Fermentation is one of the oldest biotechnological tools employed by mankind. Fermenting food gives them better sensory and nutritional qualities, the latter including vitamins, phenolic compounds, antioxidants, and antimicrobials. Kombucha is the result of the fermentation of a sweetened Camellia sinensis infusion by [...] Read more.

Fermentation is one of the oldest biotechnological tools employed by mankind. Fermenting food gives them better sensory and nutritional qualities, the latter including vitamins, phenolic compounds, antioxidants, and antimicrobials. Kombucha is the result of the fermentation of a sweetened Camellia sinensis infusion by the action of a symbiotic community of yeasts and bacteria organized in a cellulosic biofilm called SCOBY and has gained great prominence among fermented foods and beverages, with a considerable increase in its popularity in the last decade, both among consumers and within the scientific community. This is explained by the particular functional and microbial characteristics of this beverage, such as its antioxidant and antimicrobial potential, long-term stable microbial communities, its suitability for fermentation under different conditions of time and temperature, and amenability to other carbon sources besides sucrose. Thus, this review aims to present and discuss the functional, microbial, and physicochemical aspects of kombucha fermentation, covering the many challenges that arise in its production, in domestic, commercial, and legislation contexts, and the next steps that need to be taken in order to understand this drink and its complex fermentation process. Full article

(This article belongs to the Special Issue Contamination of Fermentation Systems and Methods of Control)

14 pages, 2967 KiB

Open AccessArticle

Effect of Volatile Fatty Acids Accumulation on Biogas Production by Sludge-Feeding Thermophilic Anaerobic Digester and Predicting Process Parameters

by Intisar Nasser Al-Sulaimi, Jagdeep Kumar Nayak, Halima Alhimali, Ahmed Sana and Abdullah Al-Mamun

Fermentation 2022, 8(4), 184; https://doi.org/10.3390/fermentation8040184 - 12 Apr 2022

Cited by 27 | Viewed by 6780

Abstract

Sewage sludge represents an important resource for reuse in the wastewater treatment field. Hence, thermophilic anaerobic digestion (TAD) could be an alternative technique to recover renewable resources from sludge. In the TAD biodegradation process, volatile fatty acids (VFAs) are the intermediate products of [...] Read more.

Sewage sludge represents an important resource for reuse in the wastewater treatment field. Hence, thermophilic anaerobic digestion (TAD) could be an alternative technique to recover renewable resources from sludge. In the TAD biodegradation process, volatile fatty acids (VFAs) are the intermediate products of methanogenesis. However, the higher formation and accumulation of VFAs leads to microbial stress, resulting in acidification and failure of the digester. Therefore, several batch TADs have been investigated to evaluate the VFAs production from sludge and their impact on biogas generation and biodegradation efficiency. Three types of sewage sludges, e.g., primary sludge (PS), secondary sludge (SS), and mixed sludge (MS) were used as substrates to estimate the accumulation of VFAs and yield of methane gas. The system showed the maximum total VFAs accumulation from both PS and MS as 824.68 ± 0.5 mg/L and 236.67 ± 0.5 mg/L, respectively. The dominant VFA accumulation was identified as acetic acid, the main intermediate by-product of methane production. The produced biogas from PS and MS contained 66.75 ± 0.5% and 52.29 ± 0.5% methane, respectively. The high content of methane with PS-feeding digesters was due to the higher accumulation of VFAs (i.e., 824.68 ± 0.5 mg/L) in the TAD. The study also predicted the design parameters of TAD process by fitting the lab-scale experimental data with the well-known first-order kinetic and logistic models. Such predicted design parameters are significantly important before the large-scale application of the TAD process. Full article

(This article belongs to the Special Issue Research Progress of Microorganisms in Wastewater Treatment)

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11 pages, 1471 KiB

Open AccessArticle

Isolation and Identification of Lactose-Degrading Yeasts and Characterisation of Their Fermentation-Related Ability to Produce Ethanol

by Murni Kurniawati, Nurliyani Nurliyani, Wiratni Budhijanto and Widodo Widodo

Fermentation 2022, 8(4), 183; https://doi.org/10.3390/fermentation8040183 - 12 Apr 2022

Cited by 6 | Viewed by 4137

Abstract

Kefir is traditionally produced by fermenting cow’s milk using kefir grains as a starter culture. As the viability of microbes within kefir grains is limited and preparing the grains for kefir fermentation is laborious, here, a single starter that ferments lactose and produces [...] Read more.

Kefir is traditionally produced by fermenting cow’s milk using kefir grains as a starter culture. As the viability of microbes within kefir grains is limited and preparing the grains for kefir fermentation is laborious, here, a single starter that ferments lactose and produces ethanol is developed. For this purpose, it is important to isolate yeasts that can ferment lactose and subsequently produce alcohol. This study aimed to isolate and identify yeasts from kefir and characterise their ability as single starters to produce kefir. Based on morphological and physiological evaluations, 15 presumptive yeast isolates were obtained, 10 of which grew well on lactose-containing media. Those that were able to grow on lactose using only carbon sources were subjected to molecular identification based on the internal transcribed spacer (ITS) of the 5.8 rDNA using PCR technology. Molecular identification confirmed four isolates—namely, KFA 3, KFA 7, KFA 9 and KFB 1—as belonging to Kluyveromyces marxianus. The batch fermentation data of these strains were fitted on a logistic model to obtain the carrying capacity coefficients and strain performances were compared. The kinetic modelling revealed that KFA 9 had the highest values for the carrying capacity coefficient, biomass yield and product yield, indicating that, among the four K. marxianus strains, this was superior due to its relatively fast growth and good ethanol productivity. Full article

(This article belongs to the Special Issue Fermented Foods: Traditional Processes, Innovative Strategies, and Challenges)

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16 pages, 35052 KiB

Open AccessArticle

Microbial Composition of a Traditional Fermented Wheat Preparation—Nishasta and Its Role in the Amelioration of Retinoic Acid-Induced Osteoporosis in Rats

by Aayeena Altaf, Naila H. Alkefai, Bibhu Prasad Panda, Zakiya Usmani, Saima Amin and Showkat R. Mir

Fermentation 2022, 8(4), 182; https://doi.org/10.3390/fermentation8040182 - 12 Apr 2022

Cited by 1 | Viewed by 6258

Abstract

Fermented foods have a long history of human use. The purpose of this study was to characterize the microbial composition of a traditional fermented wheat preparation—Nishasta— and to explore its effect in retinoic acid-induced osteoporosis in Wistar rats. The sample was suspended in [...] Read more.

Fermented foods have a long history of human use. The purpose of this study was to characterize the microbial composition of a traditional fermented wheat preparation—Nishasta— and to explore its effect in retinoic acid-induced osteoporosis in Wistar rats. The sample was suspended in sterile water (10% w/v), mixed thoroughly, filtered, and gradually diluted. Aliquots of dilutions were cultured in MRS (DeMan–Rogosa–Sharpe) medium, and colonies with similar morphologies were subjected to DNA extraction. The 16S rRNA gene of the isolates was amplified by polymerase chain reaction, checked by agarose gel electrophoresis, and finally identified by sequencing. Anti-osteoporosis screening of Nishasta was carried out in female Wistar rats using retinoic acid as an inducer (70 mg/kg, p.o. once a day for 14 days). Its effect on bone health parameters was determined. The bone metabolism markers such as hydroxyproline (HOP), tartrate-resistant acid phosphatase (TRACP), and alkaline phosphatase (ALP) were evaluated. The results of microbial characterization revealed the presence of ten clones of Lactobacillus plantarum in the fermented preparation with L. plantarum NF3 as the predominant strain. The average microbial count was 2.4 × 10³ CFU/g. Retinoic acid administration led to a marked disorder of various bone health markers in rats. It also increased the levels of urine calcium and phosphorus, indicating increased bone destruction. Treatment with fermented wheat (at 200, 100, and 50 mg/kg doses, p.o. daily for 42 days after the induction of osteoporosis) improved bone mineral density in a dose-dependent manner. It also improved the bone microstructure and reduced the levels of ALP, TRACP, and HOP. Micro-CT revealed that it reduced trabecular separation and increased the percent bone volume, trabecular numbers, trabecular thickness, and bone mineral density in the rats. The results showed that the fermented wheat promoted bone formation and prevented bone resorption. Our findings clearly established the effectiveness of Nishasta against osteoporosis in Wistar rats that can be partly attributed to the improved gut calcium absorption and microbiota composition. Full article

(This article belongs to the Special Issue Plant-Based Fermented Foods and Civilization Diseases)

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19 pages, 959 KiB

Open AccessEditor’s ChoiceArticle

Recombinant Protein Production in E. coli Using the phoA Expression System

by Thomas Gundinger, Stefan Kittler, Sabine Kubicek, Julian Kopp and Oliver Spadiut

Fermentation 2022, 8(4), 181; https://doi.org/10.3390/fermentation8040181 - 11 Apr 2022

Cited by 8 | Viewed by 6458

Abstract

Auto-inducible promoter systems have been reported to increase soluble product formation in the periplasm of E. coli compared to inducer-dependent systems. In this study, we investigated the phosphate (PO₄)-sensitive phoA expression system (pAT) for the production of a recombinant model antigen-binding [...] Read more.

Auto-inducible promoter systems have been reported to increase soluble product formation in the periplasm of E. coli compared to inducer-dependent systems. In this study, we investigated the phosphate (PO₄)-sensitive phoA expression system (pAT) for the production of a recombinant model antigen-binding fragment (Fab) in the periplasm of E. coli in detail. We explored the impact of non-limiting and limiting PO₄ conditions on strain physiology as well as Fab productivity. We compared different methods for extracellular PO₄ detection, identifying automated colorimetric measurement to be most suitable for at-line PO₄ monitoring. We showed that PO₄ limitation boosts phoA-based gene expression, however, the product was already formed at non-limiting PO₄ conditions, indicating leaky expression. Furthermore, cultivation under PO₄ limitation caused physiological changes ultimately resulting in a metabolic breakdown at PO₄ starvation. Finally, we give recommendations for process optimization with the phoA expression system. In summary, our study provides very detailed information on the E. coli phoA expression system, thus extending the existing knowledge of this system, and underlines its high potential for the successful production of periplasmic products in E. coli. Full article

(This article belongs to the Section Fermentation Process Design)

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13 pages, 1583 KiB

Open AccessArticle

Enhancement of PHA Production by a Mixed Microbial Culture Using VFA Obtained from the Fermentation of Wastewater from Yeast Industry

by Carolina Ospina-Betancourth, Sergio Echeverri, Claudia Rodriguez-Gonzalez, Julien Wist, Marianny Y. Combariza and Janeth Sanabria

Fermentation 2022, 8(4), 180; https://doi.org/10.3390/fermentation8040180 - 11 Apr 2022

Cited by 15 | Viewed by 5905

Abstract

Wastewater from the yeast production industry (WWY) is potentially harmful to surface water due to its high nitrogen and organic matter content; it can be used to produce compounds of higher commercial value, such as polyhydroxyalkanoates (PHA). PHA are polyester-type biopolymers synthesized by [...] Read more.

Wastewater from the yeast production industry (WWY) is potentially harmful to surface water due to its high nitrogen and organic matter content; it can be used to produce compounds of higher commercial value, such as polyhydroxyalkanoates (PHA). PHA are polyester-type biopolymers synthesized by bacteria as energy reservoirs that can potentially substitute petrochemical-derived plastics. In this exploratory work, effluent from WWY was used to produce PHA, using a three-step setup of mixed microbial cultures involving one anaerobic and two aerobic reactors. First, volatile fatty acids (VFA; 2.5 g/L) were produced on an anaerobic batch reactor (reactor A) fed with WWY, using a heat pretreated sludge inoculum to eliminate methanogenic activity. Concurrently, PHA-producing bacteria were enriched using synthetic VFA in a sequencing batch reactor (SBR, reactor C) operated for 78 days. Finally, a polyhydroxybutyrate (PHB)-producing reactor (reactor B) was assembled using the inoculum enriched with PHA-producing bacteria and the raw and distilled effluent from the anaerobic reactor as a substrate. A maximum accumulation of 17% of PHB based on cell dry weight was achieved with a yield of 1.2 g PHB/L when feeding with the distilled effluent. Roche 454 16S rRNA gene amplicon pyrosequencing of the PHA-producing reactor showed that the microbial community was dominated by the PHA-producing bacterial species Paracoccus alcalophilus (32%) and Azoarcus sp. (44%). Our results show promising PHB accumulation rates that outperform previously reported results obtained with real substrates and mixed cultures, demonstrating a sustainable approach for the production of PHA less prone to contamination than a pure culture. Full article

(This article belongs to the Topic Bioreactors: Control, Optimization and Applications)

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14 pages, 939 KiB

Open AccessReview

Bioprocess Strategy of Haematococcus lacustris for Biomass and Astaxanthin Production Keys to Commercialization: Perspective and Future Direction

by Siti Nur Hazwani Oslan, Siti Nurbaya Oslan, Rosfarizan Mohamad, Joo Shun Tan, Abdul Hafidz Yusoff, Patricia Matanjun, Ruzaidi Azli Mohd Mokhtar, Rossita Shapawi and Nurul Huda

Fermentation 2022, 8(4), 179; https://doi.org/10.3390/fermentation8040179 - 11 Apr 2022

Cited by 15 | Viewed by 4799

Abstract

Haematococcus lacustris (formerly called Haematococcus pluvialis) is regarded as the most promising microalgae for the production of natural astaxanthin, which is secondary metabolism used as a dietary supplement, also for cosmetic applications, due to its high anti-oxidant activity. Astaxanthin has a wide [...] Read more.

Haematococcus lacustris (formerly called Haematococcus pluvialis) is regarded as the most promising microalgae for the production of natural astaxanthin, which is secondary metabolism used as a dietary supplement, also for cosmetic applications, due to its high anti-oxidant activity. Astaxanthin has a wide range of biological activities and high economic potential, and currently dominates the market in its synthetic form. Furthermore, because of the difficulty of bioprocess and the high cost of cultivation, astaxanthin extracted from this microalga is still expensive due to its low biomass and pigment productivities. Large-scale biomass production in biotechnological production necessitates the processing of a large number of cultures as well as the use of both indoor and outdoor systems, such as open pond raceway systems and photo-bioreactors (PBR). The photo-bioreactors systems are suitable for mass production because growth conditions can be controlled, and the risk of contamination can be reduced to a certain extent and under specific culture parameters. This review discusses current technologies being developed to improve cultivation and operation efficiency and profitability, as well as the effect of parameter factors associated with H. lacustris cultivation on biomass and astaxanthin bioproduction, and even strategies for increasing bioproduction and market potential for H. lacustris astaxanthin. Full article

(This article belongs to the Section Microbial Metabolism, Physiology & Genetics)

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12 pages, 1549 KiB

Open AccessArticle

Development of Cistanche deserticola Fermented Juice and Its Repair Effect on Ethanol-Induced WRL68 Cell Damage

by Zhenzhen Yang and Liang Wang

Fermentation 2022, 8(4), 178; https://doi.org/10.3390/fermentation8040178 - 10 Apr 2022

Cited by 2 | Viewed by 2577

Abstract

Cistanche deserticola is a valuable Chinese herb, but traditional dry processing causes the loss of active substances. This study developed Cistanche deserticola fermented juice (CFJ) using lactic acid bacteria and optimized the fermentation process to achieve the maximum active substance content and taste. [...] Read more.

Cistanche deserticola is a valuable Chinese herb, but traditional dry processing causes the loss of active substances. This study developed Cistanche deserticola fermented juice (CFJ) using lactic acid bacteria and optimized the fermentation process to achieve the maximum active substance content and taste. More interestingly, superoxide dismutase (SOD) activity was increased during fermentation, and CFJ exerted a reparative effect on ethanol-induced cell damage. SOD activity reached 603.26 U/mL when the ratios in the total inoculum volume of Lactobacillus reuteri, Lactococcus pentosus, Streptococcus thermophilus, Bifidobacterium animalis, Lactobacillus casei, and Lactobacillus acidophilus were 31.74%, 15.71%, 17.45%, 11.65%, 9.56%, and 13.89%, respectively. Further, the optimal fermentation conditions for CFJ were determined using a response surface methodology. More importantly, CFJ promoted the proliferation of WRL68 cells, and CFJ exerted an obvious reparative effect on ethanol-treated cells, in which the cell survival rate increased to 120.35 ± 0.77% (p < 0.05). The underlying mechanism might have been that CFJ reduced the MDA content in damaged cells from 1.36 nmol/mg prot to 0.88 nmol/mg prot and increased GSH-Px and SOD activities by 48% and 72%, respectively. This study provides a theoretical basis and reference data for the fermentation of C. deserticola and its hepatoprotective activity. Full article

(This article belongs to the Section Fermentation for Food and Beverages)

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13 pages, 1262 KiB

Open AccessArticle

Wild Saccharomyces Produced Differential Aromas of Fermented Sauvignon Blanc Must

by Sandra D. C. Mendes, Stefany Grützmann Arcari, Simone Silmara Werner, Patricia Valente and Mauricio Ramirez-Castrillon

Fermentation 2022, 8(4), 177; https://doi.org/10.3390/fermentation8040177 - 10 Apr 2022

Cited by 2 | Viewed by 3297

Abstract

Nine Saccharomyces strains, previously isolated from vineyards in Southern Brazil, were used as starter cultures in fermentations of Sauvignon Blanc (SB) must at laboratory scale, to study inter-strain differences in aroma profiles. The molecular profiles differentiated the following isolates from the reference strain [...] Read more.

Nine Saccharomyces strains, previously isolated from vineyards in Southern Brazil, were used as starter cultures in fermentations of Sauvignon Blanc (SB) must at laboratory scale, to study inter-strain differences in aroma profiles. The molecular profiles differentiated the following isolates from the reference strain (SC2048), which is typically used in wine production: 06CE, 11CE, 33CE, 01PP, 12M, 13PP, 26PP, 28AD, and 41PP. Under the same conditions, each of these strains produced different concentrations and combinations of metabolites, which significantly influenced the aroma of the fermented SB must. Volatile compounds such as octanoic acid, diethyl succinate, and ethyl lactate were associated with the strains 26PP, 41PP, 01PP, and 12M, while strains 33CE, 28AD, 13PP, and 06CE were associated with the production of ethyl acetate and 1-hexanol. Strain 06CE produced 592.87 ± 12.35 µg/L 1-hexanol. In addition, the olfactory activity values (OAVs; we considered only values >1) allowed us to evaluate the participation of each compound in the aroma of the final fermented SB. In conclusion, the selected wild strains are promising candidates for improving the regional characteristics of wine. Full article

(This article belongs to the Special Issue Advances in Wine Fermentation)

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13 pages, 2362 KiB

Open AccessArticle

Algicidal Properties of Microbial Fermentation Products on Inhibiting the Growth of Harmful Dinoflagellate Species

by Barathan Balaji-Prasath, Ying Wang, Yuping Su, Minghua Chen and Yi Zheng

Fermentation 2022, 8(4), 176; https://doi.org/10.3390/fermentation8040176 - 9 Apr 2022

Cited by 2 | Viewed by 2682

Abstract

The fermentation processes of algicidal bacteria offer an eco-friendly and promising approach for controlling harmful algae blooms (HABs). The strain Ba3, previously isolated and identified as Bacillus sp., displays robust algicidal activity against HABs dinoflagellate in particular. Microbial fermentation products have also been [...] Read more.

The fermentation processes of algicidal bacteria offer an eco-friendly and promising approach for controlling harmful algae blooms (HABs). The strain Ba3, previously isolated and identified as Bacillus sp., displays robust algicidal activity against HABs dinoflagellate in particular. Microbial fermentation products have also been found to provide metabolites with multiple bioactivities, which has been shown to reduce harmful algae species’ vegetative cells and thus reduce red tide outbreaks. In this study, the microbial fermentation of algicidal bacterium Ba3 was analyzed for its potential ability of algicidal compounds. A treatment time increased the algicidal efficiency of the fermentation products against Prorocentrum donghaiense (91%) and Alexandrium tamarense (82%). Among the treatment groups, the changing trend for the 2% treatment group was faster than that for the other treatments, showing that the inhibition rate could reach 99.1% in two days. Active components were separated by organic solvent extraction and macroporous resin, and the molecular weight of the active components was analyzed by LC-MS. The result shows that the microbial fermentation products offer a potential, not practical use for controlling the outbreaks of dinoflagellate blooms. As a result of its potential application for inhibiting HABs, these findings provide an encouraging basis for promoting large-scale fermentation production and the controlling the outbreaks of red tide. Full article

(This article belongs to the Special Issue Microbial Biotransformation by Bacillus)

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13 pages, 1339 KiB

Open AccessReview

Challenges in Expression and Purification of Functional Fab Fragments in E. coli: Current Strategies and Perspectives

by Rucha S. Patil, Anupa Anupa, Jaya A. Gupta and Anurag S. Rathore

Fermentation 2022, 8(4), 175; https://doi.org/10.3390/fermentation8040175 - 9 Apr 2022

Cited by 12 | Viewed by 5722

Abstract

Microbial host systems remain the most efficient and cost-effective chassis for biotherapeutics production. Escherichia coli is often the preferred host due to ease of cloning, scale-up, high product yields, and most importantly, cost-effective cultivation. E. coli often experience difficulties in producing biologically active [...] Read more.

Microbial host systems remain the most efficient and cost-effective chassis for biotherapeutics production. Escherichia coli is often the preferred host due to ease of cloning, scale-up, high product yields, and most importantly, cost-effective cultivation. E. coli often experience difficulties in producing biologically active therapeutics such as Fab fragments, which require protein folding and subsequent three-dimensional structure development. This paper outlines the recent improvements in upstream and downstream unit operations for producing Fab fragments in E. coli. Monoclonal antibody fragments (Fab) are a rising class of biotherapeutics and their production has been optimised using coexpression of molecular chaperones such as DsbC or DnaK–DnaJ–GrpE, as well as strain engineering for post-translational modifications such as disulphide bridging. Different media systems such as EnBase and combining nitrogen source supplementation with low-temperature cultivation have resulted in improvement in cell integrity, protein expression, and protein refolding. The recovery of native proteins from insoluble inclusion bodies can be improved by adjusting refolding conditions, as well as by incorporating multimodal and affinity chromatography for achieving high product yields in purification. Recent developments summarised in this review may tune the E. coli expression system to produce more complex and glycosylated proteins for therapeutic use in the near future. Full article

(This article belongs to the Special Issue Process Intensification in Microbial Biotechnology)

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16 pages, 1261 KiB

Open AccessArticle

Silage Quality and Output of Different Maize–Soybean Strip Intercropping Patterns

by Tairu Zeng, Yushan Wu, Yafen Xin, Chen Chen, Zhaochang Du, Xiaoling Li, Junfeng Zhong, Muhammad Tahir, Bo Kang, Dongmei Jiang, Xiaochun Wang, Wenyu Yang and Yanhong Yan

Fermentation 2022, 8(4), 174; https://doi.org/10.3390/fermentation8040174 - 9 Apr 2022

Cited by 13 | Viewed by 6102

Abstract

Intercropping improves land-use efficiency under conditions of limited land and resources, but no information is currently available pertaining to land-use efficiency and silage quality based on whole-plant utilization. Therefore, a two-year field experiment was conducted with the following conditions: three maize–soybean strip intercropping [...] Read more.

Intercropping improves land-use efficiency under conditions of limited land and resources, but no information is currently available pertaining to land-use efficiency and silage quality based on whole-plant utilization. Therefore, a two-year field experiment was conducted with the following conditions: three maize–soybean strip intercropping patterns (SIPs), comprising two maize rows along with two, three, or four soybean rows (2M2S, 2M3S, and 2M4S, respectively); and two sole cropping patterns of maize (SM) and soybean (SS). The aim was to evaluate the biomass yield and silage quality under each condition. Our results showed that all SIPs had a land equivalent ratio (LER) of over 1.6 based on both fresh and dry matter yield, and a higher whole plant yield, compared to sole cropping. Specifically, 2M3S exhibited the highest whole crop dry matter LER (1.8–1.9) and yield (24.6–27.2 t ha⁻¹) compared to SM and SS (20.88–21.49 and 3.48–4.79 t ha⁻¹, respectively). Maize–soybean mixed silages also showed better fermentation quality with higher lactic acid content (1–3%) and lower ammonia-N content (2–8%) compared to SS silages, and higher crude protein content (1–1.5%) with lower ammonia-N content (1–2%) compared to SM silage. Among the intercropping patterns, 2M3S had the highest fermentation quality index V-score (92–95). Consequently, maize–soybean strip intercropping improved silage quality and biomass yield, with 2M3S being recommended, due to its highest LER and biomass yield, and most optimal silage quality. Full article

(This article belongs to the Topic Food Processing and Preservation)

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18 pages, 2020 KiB

Open AccessArticle

Design and Evaluation of a Robust Observer Using Dead-Zone Lyapunov Functions—Application to Reaction Rate Estimation in Bioprocesses

by Alejandro Rincón, Fredy E. Hoyos and Gloria M. Restrepo

Fermentation 2022, 8(4), 173; https://doi.org/10.3390/fermentation8040173 - 8 Apr 2022

Cited by 5 | Viewed by 2051

Abstract

This paper addresses the design and evaluation of a robust observer for second order bioprocesses considering unknown bounded disturbance terms and uncertainty in the dynamics of the unknown and known states. The observer design and the stability analysis are based on dead-zone Lyapunov [...] Read more.

This paper addresses the design and evaluation of a robust observer for second order bioprocesses considering unknown bounded disturbance terms and uncertainty in the dynamics of the unknown and known states. The observer design and the stability analysis are based on dead-zone Lyapunov functions, and a detailed procedure is provided. The transient response bounds and the convergence region of the unknown observer error are determined in terms of the disturbance bounds, considering persistent but bounded disturbances in the dynamics of both the known and unknown observer errors. This is a significant contribution to closely related observer design studies, in which the transient response bounds are determined, but persistent and bounded disturbances are not considered in the dynamics of the known observer error. Other important contributions are: (i) the procedure for defining the observer parameters is significantly simpler than common observer designs, since a solution to the Ricatti equation, solution to LMI constraints, or the accomplishment of eigenvalue inequality conditions are not required; (ii) discontinuous signals are not used in the observer; and (iii) the effect of the gain sign associated with the unknown state in the dynamics of the known state is explicitly and clearly considered in the observer design and in the convergence study. In addition, the guidelines for selecting the observer parameters are provided. Numerical simulation confirms the stability analysis results: the observer errors converge within a short time, with a low estimation error, if observer-parameters are properly defined. Full article

(This article belongs to the Section Fermentation Process Design)

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13 pages, 287 KiB

Open AccessArticle

Effects of Brewer Grain Meal with Enzyme Combination on Growth Performance, Nutrient Digestibility, Intestinal Morphology, Immunity, and Oxidative Status in Growing Pigs

by Waewaree Boontiam, Jinsu Hong and Winai Jaikan

Fermentation 2022, 8(4), 172; https://doi.org/10.3390/fermentation8040172 - 8 Apr 2022

Cited by 1 | Viewed by 2553

Abstract

This study investigated the effects of supplementing feed with various levels of brewer grain meal (BGM) and enzymes (amylase, xylanase, β-glucanase, lipase, cellulase, β-mannanase, phytase, and pectinase) on growth performance, nutrient digestibility, intestinal morphology, immunity, and oxidative status in growing pigs. Eighty growing [...] Read more.

This study investigated the effects of supplementing feed with various levels of brewer grain meal (BGM) and enzymes (amylase, xylanase, β-glucanase, lipase, cellulase, β-mannanase, phytase, and pectinase) on growth performance, nutrient digestibility, intestinal morphology, immunity, and oxidative status in growing pigs. Eighty growing pigs were subjected to four feed treatments (five replicates per treatment), based on a corn-soybean basal diet: feeds with 0.1% enzyme combination supplementation (PC), no enzyme supplementation (NC), 20% BGM with 0.1% enzyme combination (BGM20), and 40% BGM with 0.1% enzyme combination (BGM40). Supplementing the feed with both BGM-supplemented diets significantly increased final body weight, average daily gain, the digestibility of crude protein and ash, serum concentration of total proteins, superoxide dismutase activity, villus height in the duodenum and jejunum, and duodenal villus height to crypt depth ratio; however, it did not significantly increase blood urea nitrogen, tumor necrosis factor-alpha, malondialdehyde levels, and duodenal crypt depth compared to the NC diet (p < 0.05). Furthermore, a lower hindgut pH in the middle of the colon was detected following the BGM-supplemented diet compared to PC treatment (p = 0.005). Increased levels of triglycerides and albumin were detected in BGM20-fed pigs, whereas increased levels of glucose, total antioxidant capacity, and glutathione peroxidase but decreased interleukine-6 levels were observed in the BGM40 compared with the NC group (p = 0.05). No differences were observed in the average daily feed intake and gain to feed ratio, in the serum levels of aspartate aminotransferase or immunoglobulins (p > 0.05). The addition of up to 40% BGM combined with 0.1% enzyme supplementation positively promotes the growth performance, nutrient utilization, and intestinal health of growing pigs. Full article

(This article belongs to the Section Fermentation for Food and Beverages)

15 pages, 3104 KiB

Open AccessArticle

Beneficial Effects of Fermented Camel and Cow’s Milk in Lipid Profile, Liver, and Renal Function in Hypercholesterolemic Rats

by Yousef Mesfer Alharbi, Khaled Meghawry El-Zahar and Hassan Mirghani Mousa

Fermentation 2022, 8(4), 171; https://doi.org/10.3390/fermentation8040171 - 8 Apr 2022

Cited by 4 | Viewed by 3403

Abstract

As hyperlipidemia has been associated with cardiovascular diseases, this study investigated the influence of probiotic-fermented camel and cow’s milk on blood lipid profiles in hypercholesterolemic rats. When tested, probiotic-fermented camel and cow’s milk exhibited the highest overall acceptance score in flavor and texture. [...] Read more.

As hyperlipidemia has been associated with cardiovascular diseases, this study investigated the influence of probiotic-fermented camel and cow’s milk on blood lipid profiles in hypercholesterolemic rats. When tested, probiotic-fermented camel and cow’s milk exhibited the highest overall acceptance score in flavor and texture. Forty-eight male Wistar rats were divided into eight groups (n = 6). The first group served as normal control, while groups 2–8 were fed on a high-fat (HFD), high-cholesterol diet throughout the experimental period and treated with different types of fermented milks. Feeding rats on probiotic-fermented milk resulted in a significant decrease in the level of triglycerides (TG), cholesterol, and LDL compared with the positive control group. Albumin and total protein concentrations increased significantly, while ALT, AST, and creatinine were significantly reduced in rats fed on probiotic-fermented milk. The results indicated that probiotic-fermented milk might improve liver and kidney functions in hypercholesterolemic rats. These findings highlighted the ameliorative potentials of camel milk against hyperlipidemia and oxidative stress in rats. Full article

(This article belongs to the Section Fermentation for Food and Beverages)

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14 pages, 1733 KiB

Open AccessArticle

Multi-Objective Statistical Optimization of Pectinolytic Enzymes Production by an Aspergillus sp. on Dehydrated Coffee Residues in Solid-State Fermentation

by Jimmy Núñez Pérez, Brayan Santiago Chávez Arias, Juan Carlos de la Vega Quintero, Santiago Zárate Baca and José Manuel Pais-Chanfrau

Fermentation 2022, 8(4), 170; https://doi.org/10.3390/fermentation8040170 - 8 Apr 2022

Cited by 12 | Viewed by 3370

Abstract

Pectinolytic enzymes are a group of enzymes widely used in the food industry. They can be obtained through a wide range of by-products and agricultural and agro-industrial waste by the action of fungi, such as Aspergillus spp., by solid-state fermentation (SSF). A wild [...] Read more.

Pectinolytic enzymes are a group of enzymes widely used in the food industry. They can be obtained through a wide range of by-products and agricultural and agro-industrial waste by the action of fungi, such as Aspergillus spp., by solid-state fermentation (SSF). A wild strain of an Aspergillus sp. isolated in the Universidad Técnica del Norte (UTN) was used to obtain pectinolytic enzymes from dehydrated coffee waste (pulp and husk) derived from coffee cherries cultivated in the Ecuadorian Andean regions. It was possible to find a condition in which the production of pectinases (expressed as Enzymatic Activity (EA)) and the concentration of spores (S) were simultaneously maximized, using the response surface methodology, in a 3-level factorial design, by SSF in simple tray-type bioreactors. After the analysis and optimization of quadratic models, three confirmatory experiments were performed in the unique optimal condition recommended (35 °C and 79% relative humidity), obtaining 29.9 IU/g and 2.64 × 10⁶ #Sp./g for EA and S, respectively; these values coincided with those predicted by the quadratic models, demonstrating their validity. The values obtained in this study are similar to those previously obtained by other authors. Full article

(This article belongs to the Section Industrial Fermentation)

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15 pages, 484 KiB

Open AccessArticle

Enhancing the Productivity and Stability of Superoxide Dismutase from Saccharomyces cerevisiae TBRC657 and Its Application as a Free Radical Scavenger

by Phitsanu Pinmanee, Kamonwan Sompinit, Jantima Arnthong, Surisa Suwannarangsee, Angkana Jantimaporn, Mattaka Khongkow, Thidarat Nimchua and Prakit Sukyai

Fermentation 2022, 8(4), 169; https://doi.org/10.3390/fermentation8040169 - 6 Apr 2022

Cited by 5 | Viewed by 3283

Abstract

Superoxide dismutase (SOD) is crucial antioxidant enzyme that plays a role in protecting cells against harmful reactive oxygen species (ROS) which are generated inside cells. Due to its functionality, SOD is used in many applications. In this study, Saccharomyces cerevisiae TBRC657 was selected [...] Read more.

Superoxide dismutase (SOD) is crucial antioxidant enzyme that plays a role in protecting cells against harmful reactive oxygen species (ROS) which are generated inside cells. Due to its functionality, SOD is used in many applications. In this study, Saccharomyces cerevisiae TBRC657 was selected as the SOD producer due to its high SOD production. After investigating an optimized medium, the major components were found to be molasses and yeast extract, which improved SOD production up to 3.97-fold compared to a synthetic medium. In addition, the optimized medium did not require any induction, which makes it suitable for applications in large-scale production. The SOD formulation was found to increase the stability of the conformational structure and prolong shelf-life. The results show that 1.0% (w/w) trehalose was the best additive, in giving the highest melting temperature by the DSF method and maintaining its activity at more than 80% after storage for 6 months. The obtained SOD was investigated for its cytotoxicity and ROS elimination against fibroblast cells. The results indicate that the SOD enhanced the proliferation and controlled ROS level inside the cells. Thus, the SOD obtained from S. cerevisiae TBRC657 cultured in the optimized medium could be a candidate for use as a ROS scavenger, which can be applied in many industries. Full article

(This article belongs to the Topic Bioreactors: Control, Optimization and Applications)

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7 pages, 211 KiB

Open AccessEditorial

Food Waste Valorization

by Alessia Tropea

Fermentation 2022, 8(4), 168; https://doi.org/10.3390/fermentation8040168 - 6 Apr 2022

Cited by 26 | Viewed by 5429

Abstract

During the industrial processing of agricultural or animal products, large amounts of waste are produced. These wastes, generated in large amounts throughout the seasons of the year, can be considered the most abundant renewable resources on earth. Due to the large availability and [...] Read more.

During the industrial processing of agricultural or animal products, large amounts of waste are produced. These wastes, generated in large amounts throughout the seasons of the year, can be considered the most abundant renewable resources on earth. Due to the large availability and richness in components of these raw materials, there is a great interest in their reuse, both from an economical and environmental point of view. This economical interest is based on the fact that a high quantity of such wastes could be used as low-cost raw materials for the production of new value-added compounds, with a further production cost reduction. The environmental concern is derived from their composition, especially the agro-industrial wastes that can contain potentially toxic compounds, which may cause deterioration of the environment when uncontrolled wastes are either burned, left on the soil to decay naturally, or buried underground. Moreover, these materials exhibit both high biochemical oxygen demand (BOD) and chemical oxygen demand (COD) values and give rise to serious pollution problems if not properly discarded. Recycling and transformation of food wastes represent a great opportunity in supporting sustainable development by their conversion into value-added products through the fermentation process. Full article

(This article belongs to the Special Issue Food Waste Valorization)

12 pages, 3145 KiB

Open AccessArticle

Effects of Microbial Inoculants on Fermentation Quality and Aerobic Stability of Paper Mulberry Silages Prepared with Molasses or Cellulase

by Ying-Chao Zhang, Xue-Kai Wang, Yan-Li Lin, Yu-Long Zheng, Kui-Kui Ni and Fu-Yu Yang

Fermentation 2022, 8(4), 167; https://doi.org/10.3390/fermentation8040167 - 6 Apr 2022

Cited by 3 | Viewed by 2406

Abstract

Paper mulberry (Broussonetia papyrifera L.) is an unconventional forage with high crude protein content and is widely used in China. In order to evaluate the pattern of fermentation quality and the aerobic stability when inoculated with lactic acid bacteria, laboratory-scale silage was [...] Read more.

Paper mulberry (Broussonetia papyrifera L.) is an unconventional forage with high crude protein content and is widely used in China. In order to evaluate the pattern of fermentation quality and the aerobic stability when inoculated with lactic acid bacteria, laboratory-scale silage was prepared. The experimental groups included a control group (CK), a Lactobacillus plantarum ‘LC365283’ (selected from paper mulberry silage) treatment (L1), a commercial inoculant Lactobacillus plantarum treatment (GF), a commercial inoculant Lactobacillus buchneri treatment (FR), a 3% molasses treatment (MO), a 150 U/g cellulase treatment (CE), and their combinations (MO + L1, MO + GF, MO + FR, CE + L1, CE + GF, and CE + FR). The changes in bacterial community and composition of the fermentation products were evaluated after being ensiled for 30 days and unsealed for 1, 3, 5, and 7 days. Compared with the CK, MO and CE, the silages treated with L1, MO + L1, and CE + L1 showed higher lactic acid concentrations, lower pH values, and lower ammonia nitrogen concentrations (p < 0.05). During the first 3 days of aerobic exposure, the pH values and organic acid content changed slightly in all treatments. The present study suggests that addition of L1 was better than commercial inoculum, and the paper mulberry silages could be well preserved after being unsealed for 3 days. Full article

(This article belongs to the Special Issue Silage Fermentation)

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14 pages, 8100 KiB

Open AccessArticle

NTH2 1271_1272delTA Gene Disruption Results in Salt Tolerance in Saccharomyces cerevisiae

by Alejandro Hernández-Soto, José Pablo Delgado-Navarro, Miguel Benavides-Acevedo, Sergio A. Paniagua and Andres Gatica-Arias

Fermentation 2022, 8(4), 166; https://doi.org/10.3390/fermentation8040166 - 5 Apr 2022

Cited by 1 | Viewed by 3945

Abstract

Trehalose is a common energy reservoir, and its accumulation results in osmotic protection. This sugar can accumulate through its synthesis or slow degradation of the reservoir by trehalase enzymes. Saccharomyces cerevisiae contains two neutral trehalases, NTH1 and NTH2, responsible for 75% and [...] Read more.

Trehalose is a common energy reservoir, and its accumulation results in osmotic protection. This sugar can accumulate through its synthesis or slow degradation of the reservoir by trehalase enzymes. Saccharomyces cerevisiae contains two neutral trehalases, NTH1 and NTH2, responsible for 75% and 25% of the enzymatic metabolism. We were interested in the loss-of-function of both enzymes with CRISPR/Cas9. The later NTH2 was of great importance since it is responsible for minor metabolic degradation of this sugar. It was believed that losing its functionality results in limited osmotic protection. We constructed an osmotolerant superior yeast capable of growing in 0.85 M NaCl after independent nth21271_1272delTA mutation by CRISPR/Cas9 technology, compared with nth1 893_894insT and wild type. We suggest that this yeast model could give clues to breeding commercial yeast resulting in non-GMO salinity-tolerant strains. Full article

(This article belongs to the Special Issue Microbial Metabolism in Fermentation Process)

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10 pages, 2568 KiB

Open AccessArticle

Study on Comparisons of Bio-Hydrogen Yield Potential and Energy Conversion Efficiency between Stem and Leaf of Sweet Potato by Photo-Fermentation

by Haorui Zhang, Tingzhou Lei, Shijie Lu, Shengnan Zhu, Yameng Li, Quanguo Zhang and Zhiping Zhang

Fermentation 2022, 8(4), 165; https://doi.org/10.3390/fermentation8040165 - 5 Apr 2022

Cited by 7 | Viewed by 2469

Abstract

The source of raw materials for hydrogen production can be expanded by using vine waste as a substrate. Likewise, the effectiveness of vine waste can also be improved. However, plant parts such as stems and leaves often differ in physicochemical properties, which significantly [...] Read more.

The source of raw materials for hydrogen production can be expanded by using vine waste as a substrate. Likewise, the effectiveness of vine waste can also be improved. However, plant parts such as stems and leaves often differ in physicochemical properties, which significantly affects the effectiveness of biochemical transformation. In this research, sweet potato was used as substrate in photo-fermentative hydrogen production (PFHP) to evaluate differences in bio-hydrogen production yield potential and energy conversion efficiency for its stem and leaf. Physicochemical properties were determined using the following techniques: elementary analysis, SEM, and X-ray diffraction. The Gompertz model was adopted to analyze the kinetic parameters, and energy conversion efficiency was calculated. The results showed that stem samples with loose structures produced more hydrogen, with a total cellulose and hemicellulose content of 44.6%, but crystallinity was only 29.67%. Cumulative bio-hydrogen yield of stem was 66.03 mL/g TS, which was 3.59 times higher than that of leaf. An increase of 258.93% in energy conversion efficiency was obtained when stem was used for PFHP. In conclusion, stem samples were more suitable for PFHP than leaf samples. Full article

(This article belongs to the Section Fermentation Process Design)

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14 pages, 3637 KiB

Open AccessArticle

Wineinformatics: Comparing and Combining SVM Models Built by Wine Reviews from Robert Parker and Wine Spectator for 95 + Point Wine Prediction

by Qiuyun Tian, Brittany Whiting and Bernard Chen

Fermentation 2022, 8(4), 164; https://doi.org/10.3390/fermentation8040164 - 4 Apr 2022

Cited by 3 | Viewed by 2494

Abstract

Wineinformatics is among the new fields in data science that use wine as domain knowledge. To process large amounts of wine review data in human language format, the computational wine wheel is applied. In previous research, the computational wine wheel was created and [...] Read more.

Wineinformatics is among the new fields in data science that use wine as domain knowledge. To process large amounts of wine review data in human language format, the computational wine wheel is applied. In previous research, the computational wine wheel was created and applied to different datasets of wine reviews developed by Wine Spectator. The goal of this research is to explore the development and application of the computational wine wheel to reviews from a different reviewer, Robert Parker. For comparison, this research collects 513 elite Bordeaux wines that were reviewed by both Robert Parker and Wine Spectator. The full power of the computational wine wheel is utilized, including NORMALIZED, CATEGORY, and SUBCATEGORY attributes. The datasets are then used to predict whether the wine is a classic wine (95 + scores) or not (94 − scores) using the black-box classification algorithm support vector machine. The Wine Spectator’s dataset, with a combination of NORMALIZED, CATEGORY, and SUBCATEGORY attributes, achieves the best accuracy of 76.02%. Robert Parker’s dataset also achieves an accuracy of 75.63% out of all the attribute combinations, which demonstrates the usefulness of the computational wine wheel and that it can be effectively adopted in different wine reviewers’ systems. This paper also attempts to build a classification model using both Robert Parker’s and Wine Spectator’s reviews, resulting in comparable prediction power. Full article

(This article belongs to the Section Fermentation for Food and Beverages)

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13 pages, 1898 KiB

Open AccessArticle

Isolation and Characterization of a Cholesterol-Lowering Bacteria from Bubalus bubalis Raw Milk

by Abdul Hameed, Carla Condò, Isfahan Tauseef, Maryam Idrees, Shakira Ghazanfar, Arshad Farid, Muhammad Muzammal, Mohammed Al Mohaini, Abdulkhaliq J. Alsalman, Maitham A. Al Hawaj, Charles Oluwaseun Adetunji, Wadzani Palnam Dauda, Yasir Hameed, Yousef N. Alhashem and Abeer A. Alanazi

Fermentation 2022, 8(4), 163; https://doi.org/10.3390/fermentation8040163 - 4 Apr 2022

Cited by 34 | Viewed by 4699

Abstract

Probiotics retrieved from animal sources have substantial health benefits for both humans and animals. The present study was designed to identify lactic acid bacteria (LAB) isolated from domestic water buffalo milk (Bubalus bubalis) and to evaluate their potential as target-based probiotics. [...] Read more.

Probiotics retrieved from animal sources have substantial health benefits for both humans and animals. The present study was designed to identify lactic acid bacteria (LAB) isolated from domestic water buffalo milk (Bubalus bubalis) and to evaluate their potential as target-based probiotics. Forty-six LAB strains were isolated and, among them, five strains (NMCC-M2, NMCC-M4, NMCC-M5, NMCC-M6, and NMCC-M7) were regarded as possible probiotics on the basis of their phenotypic and biochemical properties. These isolates were molecularly identified as Weissella confusa (NMCC-M2), Leuconostoc pseudo-mesenteroides (NMCC-M4), Lactococcus lactis Subsp. hordniae (NMCC-M5), Enterococcus faecium NMCC-M6, and Enterococcus lactis NMCC-M7. The tested bacterial strains showed significant antimicrobial activity, susceptibility to antibiotics, acid and bile tolerance, sugar fermentation, enzymatic potential, and nonhemolytic characteristics. Interestingly, NMCC-M2 displayed the best probiotic features including survival at pH 3 and 0.5% (w/v) bile salts, complete susceptibility to the tested antibiotics, high enzymatic potential, and in vitro cholesterol reduction (48.0 µg/mL for NMCC-M2) with 0.3% bile salt supplementation. Therefore, the isolated strain NMCC-M2 could be considered as a potential target-based probiotic in cholesterol-lowering fermented food products. Full article

(This article belongs to the Special Issue New Insights into the Application of Lactic Acid Bacteria Strain in the Fermentation)

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13 pages, 319 KiB

Open AccessReview

Fermented Foods and Their Role in Respiratory Health: A Mini-Review

by Periyanaina Kesika, Subramanian Thangaleela, Bhagavathi Sundaram Sivamaruthi, Muruganantham Bharathi and Chaiyavat Chaiyasut

Fermentation 2022, 8(4), 162; https://doi.org/10.3390/fermentation8040162 - 3 Apr 2022

Cited by 7 | Viewed by 4515

Abstract

Fermented foods (FFs) hold global attention because of their huge advantages. Their health benefits, palatability, preserved, tasteful, and aromatic properties impart potential importance in the comprehensive evaluation of FFs. The bioactive components, such as minerals, vitamins, fatty acids, amino acids, and other phytochemicals [...] Read more.

Fermented foods (FFs) hold global attention because of their huge advantages. Their health benefits, palatability, preserved, tasteful, and aromatic properties impart potential importance in the comprehensive evaluation of FFs. The bioactive components, such as minerals, vitamins, fatty acids, amino acids, and other phytochemicals synthesized during fermentation, provide consumers with several health benefits. Fermentation of food is an ancient process that has met with many remarkable changes owing to the development of scientific technologies over the years. Initially, fermentation relied on back-slapping. Nowadays, starter cultures strains are specifically chosen for the type of fermentation process. Modern biotechnological methods are being implemented in the fermentation process to achieve the desired product in high quality. Respiratory and gastrointestinal tract infections are the most severe health issues affecting human beings of all age groups, especially children and older adults, during this COVID-19 pandemic period. Studies suggest that the consumption of probiotic Lactobacillus strains containing fermented foods protects the subjects from common infectious diseases (CIDs, which is classified as upper respiratory tract infections, lower respiratory tract infections and gastrointestinal infections) by improving the host’s immune system. Further studies are obligatory to develop probiotic-based functional FFs that are effective against CIDs. Presently, we are urged to find alternative, safe, and cost-effective prevention measures against CIDs. The current manuscript briefs the production of FFs, functional properties of FFs, and their beneficial effects against respiratory tract infections. It summarizes the outcomes of clinical trials using human subjects on the effects of supplementation of FFs. Full article

(This article belongs to the Special Issue Food Fermentation for Better Nutrition, Health and Sustainability)

14 pages, 2263 KiB

Open AccessReview

Recent Developments in Lignocellulosic Biofuels, a Renewable Source of Bioenergy

by Ashutosh Kumar Rai, Naief Hamoud Al Makishah, Zhiqiang Wen, Govind Gupta, Soumya Pandit and Ram Prasad

Fermentation 2022, 8(4), 161; https://doi.org/10.3390/fermentation8040161 - 3 Apr 2022

Cited by 39 | Viewed by 7650

Abstract

Biofuel consists of non-fossil fuel derived from the organic biomass of renewable resources, including plants, animals, microorganisms, and waste. Energy derived from biofuel is known as bioenergy. The reserve of fossil fuels is now limited and continuing to decrease, while at the same [...] Read more.

Biofuel consists of non-fossil fuel derived from the organic biomass of renewable resources, including plants, animals, microorganisms, and waste. Energy derived from biofuel is known as bioenergy. The reserve of fossil fuels is now limited and continuing to decrease, while at the same time demand for energy is increasing. In order to overcome this scarcity, it is vital for human beings to transfer their dependency on fossil fuels to alternative types of fuel, including biofuels, which are effective methods of fulfilling present and future demands. The current review therefore focusses on second-generation lignocellulosic biofuels obtained from non-edible plant biomass (i.e., cellulose, lignin, hemi-celluloses, non-food material) in a more sustainable manner. The conversion of lignocellulosic feedstock is an important step during biofuel production. It is, however, important to note that, as a result of various technical restrictions, biofuel production is not presently cost efficient, thus leading to the need for improvement in the methods employed. There remain a number of challenges for the process of biofuel production, including cost effectiveness and the limitations of various technologies employed. This leads to a vital need for ongoing and enhanced research and development, to ensure market level availability of lignocellulosic biofuel. Full article

(This article belongs to the Special Issue Biofuels Production and Processing Technology)

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13 pages, 4990 KiB

Open AccessArticle

Butanol Production by a Novel Efficient Method Using Mixed Cultures of Clostridium beijerinckii and Arthrobacter sp. in Stirred-Tank and Gas-Lift Bioreactors

by Chalida Daengbussadee, Lakkana Laopaiboon and Pattana Laopaiboon

Fermentation 2022, 8(4), 160; https://doi.org/10.3390/fermentation8040160 - 2 Apr 2022

Cited by 4 | Viewed by 3511

Abstract

Arthrobacter sp. BCC 72131, an obligate aerobic bacterium, was used to create anaerobic conditions, and Clostridium beijerinckii TISTR 1461 was used as a butanol producer in an acetone-butanol–ethanol (ABE) fermentation. Sweet sorghum juice (SSJ) medium containing 60 g/L of total sugar supplemented with [...] Read more.

Arthrobacter sp. BCC 72131, an obligate aerobic bacterium, was used to create anaerobic conditions, and Clostridium beijerinckii TISTR 1461 was used as a butanol producer in an acetone-butanol–ethanol (ABE) fermentation. Sweet sorghum juice (SSJ) medium containing 60 g/L of total sugar supplemented with 1.27 g/L of (NH₄)₂SO₄ was used as a butanol production (BP) medium. Arthrobacter sp. was inoculated into the BP medium in 1-L screw-capped bottles. After 2, 4, 6 and 12 h of Arthrobacter sp. cultivation at 30 °C, C. beijerinckii was transferred into the BP medium to start butanol production at 37 °C. The results showed that C. beijerinckii inoculation after 6 h of Arthrobacter sp. cultivation gave the highest butanol titer (P_B) at 12.56 g/L, with a butanol yield (Y_B/S) and volumetric butanol productivity (Q_B) of 0.34 g/g and 0.23 g/L·h, respectively. These values are approximately 10–27% higher than those of the control experiment using a single culture of C. beijerinckii TISTR 1461 and oxygen-free nitrogen (OFN) gas flushing to create anaerobic conditions. Field emission scanning electron microscopic (FE-SEM) images of Clostridium cells, as well as protein and free amino nitrogen concentrations in the broth during butanol fermentation were also studied to confirm the results. The butanol fermentation was then carried out in a 5.6-L stirred-tank and a 1.2-L low-cost gas-lift bioreactor by the mixed cultures using the optimal time of Clostridium inoculation. The P_B, Y_B/S and Q_B values obtained were not significantly different from those in the 1-L screw-capped bottles. Hence, Arthrobacter sp. can be used as a novel method to create anaerobic conditions instead of a traditional method employing OFN gas flushing. Using mixed cultures of Arthrobacter sp. BCC 72131 and C. beijerinckii TISTR 1461 is a practical method to produce butanol on a large-scale, both in complex and low-cost bioreactors. Full article

(This article belongs to the Section Fermentation Process Design)

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