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Article

Secondary Metabolites with Antioxidant and Antimicrobial Activities from Camellia fascicularis

by
Jiandong Tang
1,
Ruonan Li
1,
Boxiao Wu
1,
Junrong Tang
1,
Huan Kan
1,
Ping Zhao
1,
Yingjun Zhang
2,
Weihua Wang
1,* and
Yun Liu
1,*
1
Key Laboratory of Forest Resources Conservation and Utilization in the Southwest Mountains of China Ministry of Education, Southwest Forestry University, Kunming 650224, China
2
State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650224, China
*
Authors to whom correspondence should be addressed.
Curr. Issues Mol. Biol. 2024, 46(7), 6769-6782; https://doi.org/10.3390/cimb46070404
Submission received: 26 May 2024 / Revised: 28 June 2024 / Accepted: 30 June 2024 / Published: 2 July 2024
(This article belongs to the Special Issue Molecular Insights into Food-Derived Natural Products and Their Biological Activities)
Browse Figures
Versions Notes

Abstract

:
Camellia fascicularis has important ornamental, medicinal, and food value. It also has tremendous potential for exploiting bioactivities. However, the bioactivities of secondary metabolites in C. fascicularis have not been reported. The structures of compounds were determined by spectral analysis and nuclear magnetic resonance (NMR) combined with the available literature on secondary metabolites of C. fascicularis leaves. In this study, 15 compounds were identified, including 5 flavonoids (1–5), a galactosylglycerol derivative (6), a terpenoid (7), 4 lignans (8–11), and 4 phenolic acids (12–15). Compounds 6–7 and 9–12 were isolated from the genus Camellia for the first time. The remaining compounds were also isolated from C. fascicularis for the first time. Evaluation of antioxidant and antimicrobial activities revealed that compounds 5 and 8–11 exhibited stronger antioxidant activity than the positive drug ascorbic acid, while compounds 7, 13, and 15 showed similar activity to ascorbic acid. The minimum inhibitory concentration (MIC) of antibacterial activity for compounds 5, 7, 9, 11, and 13 against Pseudomonas aeruginosa was comparable to that of the positive control drug tetracycline at a concentration of 62.50 µg/mL; other secondary metabolites inhibited Escherichia coli and Staphylococcus aureus at concentrations ranging from 125–250 µg/mL.

1. Introduction

Camellia fascicularis, a genus of Camellia in the family Theaceae, is an endemic plant in Yunnan province, China. C. fascicularis, which is a rare species resource with unique golden petals, also known as “giant panda in the plant kingdom”, “queen of the tea family”, and “living fossil of plants” was first discovered in Hekou County and only distributed in Gejiu, Maguan, and Hekou counties [1]. C. fascicularis leaves possess high amino acid and mineral content and are considered an edible plant resource with high nutritional and health value [2,3]. There is limited literature on the metabolites of Camellia, with polyphenols, flavonoids, saponins, and steroids being the primary active components involved [4,5,6,7,8]. It has been proved by experiments that the flowers and leaves of C. fascicularis, in addition to being used as a tea, have many pharmacological effects such as antioxidant [9], anti-tumor [10,11], and anti-inflammatory [12,13] attributes. Due to its limited distribution in Yunnan, the investigation into secondary metabolites of C. fascicularis commenced relatively late; nevertheless, it harbors immense potential for exploring its biological activities.
The isolation and identification of monomeric active compounds from complex plant components is a pivotal objective in the field of natural product chemistry research [14]. However, the bioactivities of secondary metabolites in C. fascicularis have not been reported. Considering the significance of previous research findings in exploring the bioactivities of C. fascicularis, this study aimed to investigate the secondary metabolites and bioactivities (antioxidant and antimicrobial) present in the acetate fraction of the methanol extract derived from C. fascicularis leaves. This investigation facilitated a comprehensive understanding of the composition of monomeric compounds within C. fascicularis leaves, while also anticipating the isolation of novel compounds with remarkable bioactive properties.

2. Materials and Methods

2.1. Instrumentation

The following instruments were used in the study: Bruker AV 500 MHz Nuclear Magnetic Resonance Instrument, (Bruker, Saarbrucken, Germany), XEVO G2-XS Q-Tof High Resolution Mass Spectrometer (Waters, Milford, MA, USA), NP7000 Semi-preparative Liquid Phase (Jiangsu Hanbang Technology Co., Ltd., Huaian, China), AX224ZH\E Electronic Balance (Ohaus Instruments, Changzhou Co., Ltd., Changzhou, China), N-1300 rotary evaporator, CA-111 cold trap (Shanghai Ailang Instrument Co., Ltd., Shanghai, China), SHZ-DⅢ circulating water vacuum pump (Gongyi Yuhua Instrument Co., Ltd., Gongyi, China), SpectraMax 190 enzyme labeler (Molecular Devices Co., Ltd., Shanghai, China), ZQZY-CF9.9 oscillating incubator (Shanghai Zhichu Instrument Co., Ltd., Shanghai, China), and a ZF-7 triple-use UV analyzer (Shanghai Jiapeng Science and Technology Co., Ltd., Shanghai, China).

2.2. Chemicals and Reagents

2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and ascorbic acid were obtained from Beijing Solarbio Science & Technology Co., Ltd. (Beijing, China). Methanol (HPLC grade) was purchased from Shanghai Xingke High Purity Solvent Co., Ltd. (Shanghai, China). Dimethyl sulfoxide (DMSO), and all other chemicals of analytical grade were purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). Macroporous resin D101 and Sephadex LH–20 were purchased from Shanghai Yuanye Biotechnology Co., Ltd. (Shanghai, China). Column chromatography silica gel (200–300 mesh and 300–400 mesh) and thin-layer chromatography silica gel plates were purchased from Qingdao Ocean Chemical Co., Ltd. (Qingdao, China), and middle chromatogram isolated (MCI) was purchased from Beijing Lvbaicao Technology Development Co., Ltd. (Beijing, China). The reagents (industrial grade) used in the column chromatography process were purchased from Yunnan Liyan Technology Co Ltd. (Kunming, China).

2.3. Plant Material

The voucher specimen (52,860) of C. fascicularis was identified by taxonomist Min Tianlu and preserved in the Herbarium of Kunming Institute of Botany, Chinese Academy of Sciences. The leaves of C. fascicularis used in this experiment were obtained from Dawei Mountain Nature Reserve, Hekou County, Yunnan Province, China, in December 2019, and were identified as C. fascicularis by taxonomist Prof. Xiang Jianying of Southwest Forestry University.

2.4. Extraction and Isolation

The 10.7 kg of dried C. fascicularis samples were crushed to about 40 mesh and extracted with 95% methanol (100 L) with stirring assistance at 50 °C for 3, 2, and 1 h, respectively. The extracts were combined and the solvents were evaporated under low pressure at 50 °C. The methanol extract of C. fascicularis (868.3 g) was ultimately obtained. Subsequently, 5 L of distilled water was added for thorough ultrasonic mixing, followed by three extractions using equal volumes (5 L) of industrial ethyl acetate. The ethyl acetate phase extract (177.8 g) was obtained via low-pressure rotary evaporation at 40 °C, and subsequently mixed with macroporous resin (267.0 g) before being loaded onto a column and eluted using a MeOH:H2O gradient (0:1→1:0). The resulting fractions were combined based on thin-layer chromatography detection, yielding 4 distinct fractions (Fr. I–IV). The combined fraction of (Fr. II–III) from the extract was subjected to silica gel column chromatography, employing a gradient elution of CHCl3:MeOH (50:1, 30:1, 15:1, 10:1, 5:1, 2:1, 1:1, v/v), resulting in the isolation of 8 fractions (Table 1).
Fr. G was eluted with a CHCl3:MeOH = 2:1, v/v and yielded 9.0 g. It was separated by MCI reversed-phase column chromatography and gradient elution with MeOH–H2O (2:3, 1:1, 3:2, 7:3, 4:1, 9:1, 10:0, v/v) to obtain 9 flow fractions (Ga–Gi). Fr. Gd was further purified and impurities removed using Sephadex LH–20 (CH2Cl2:MeOH = 1:1), followed by separation by elution with small orthophase silica gel (CH2Cl2:MeOH), and finally purified using preparative high-performance liquid chromatography (PHPLC) to give monomeric compound 1 (3.1 mg, Vmethanol:water = 58:42, tR = 8 min), 2 (3.2 mg, Vmethanol:water = 58:42, tR = 10 min), and 3 (5.3 mg, Vmethanol:water = 59:41, tR = 7 min). Fr. Ge was further purified and decontaminated using Sephadex LH–20 (CH2Cl2:MeOH = 1:1) to give compound 4 (13.0 mg) and 5 (5.6 mg). Fr. Gi was further purified and impurities removed using Sephadex LH–20 (CH2Cl2:MeOH = 1:1), followed by separation by elution with small orthophase silica gel (CH2Cl2:MeOH), and finally purified using PHPLC to give monomeric compound 6 (7.0 mg, Vmethanol:water = 83:17, tR = 22 min).
Fr. A was eluted with a CHCl3:MeOH = 50:1, v/v and yielded 6.0 g. It was separated by MCI column chromatography and gradient elution with MeOH–H2O (2:3, 1:1, 3:2, 7:3, 4:1, 9:1, 10:0, v/v) to obtain 9 flow fractions (Aa–Ai). Fr. Ab was further purified and impurities removed using Sephadex LH–20 (MeOH:H2O = 95:5) and finally purified using PHPLC to give monomeric compound 7 (5.8 mg, Vmethanol:water = 27:73, tR = 25 min). Fr. Ae was further purified and impurities removed using Sephadex LH–20 (MeOH:H2O = 95:5) and finally purified using PHPLC to give monomeric compound 8 (29.1 mg, Vmethanol:water = 54:46, tR = 18 min), 9 (4.8 mg, Vmethanol:water = 54:46, tR = 20 min), 10 (4.3 mg, Vmethanol:water = 54:46, tR = 22 min), and 11 (5.7 mg, Vmethanol:water = 54:46, tR = 25 min). Fr. Aa was further purified and impurities removed using Sephadex LH–20 (MeOH:H2O = 95:5) and finally purified using PHPLC to give monomeric compound 12 (29.1 mg, Vmethanol:water = 30:70, tR = 12 min), 13 (4.8 mg, Vmethanol:water = 30:70, tR = 14 min), 14 (4.3 mg, Vmethanol:water = 30:70, tR = 16 min), and 15 (7.2 mg, Vmethanol:water = 30:70, tR = 16 min).
After obtaining the monomeric compounds through purification, the organic solvent was evaporated and quantified. A suitable deuterium substitute reagent was selected for dissolution and sent for testing, with TMS used as an internal standard. The isolation and purification process of compounds 1–15 is illustrated in Figure 1.

2.5. Chemical Structure Analysis

Secondary metabolites investigation on the leaves of C. fascicularis, afforded 15 compounds, including 5 flavonoids (1–5), a galactosylglycerol derivative (6), a terpenoid (7), 4 lignans (8–11), and 4 phenolic acids (12–15). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature. Compounds 6–7 and 9–12 were isolated from the genus Camellia for the first time. The remaining compounds were also isolated from this plant for the first time. The structures of the known compounds (Figure 2).
Tsubakioside A (1): Pale yellow powder, HRESIMS m/z 749.1808 [M + Na]+ (calcd. for C32H38O19); 1H NMR (500 MHz, Methanol-d4) δH 8.06 (2H, d, J = 8.6 Hz, H-2’ and 6’), 6.89 (2H, d, J = 8.6 Hz, H-3’ and 5’), 6.41 (1H, d, J = 2.0 Hz, H-8), 6.21 (1H, d, J = 2.0 Hz, H-6), 5.12 (1H, d, J = 7.4 Hz, Glc H-1), 4.51 (1H, d, J = 1.4 Hz, Rha H-1), 4.34 (1H, d, J = 7.5 Hz, Xyl H-1), 3.84–3.18 (15H, m), 1.10 (3H, d, J = 6.1 Hz, Rha 5-CH3). 13C NMR (126 MHz, Methanol-d4) δC 179.7 (C-4), 166.9 (C-7),163.4 (C-5), 161.9 (C-4’), 159.8 (C-9), 159.0 (C-2), 135.8 (C-3), 132.8 (C-2’ and 6’), 123.2 (C-1’), 116.5 (C-3’ and 5’), 106.8 (Xyl C-1), 105.9 (C-10), 104.8 (Glc C-1), 102.7 (Rha C-1), 100.5 (C-6), 95.5 (C-8), 82.8 (Rha C-3), 78.5 (Glc C-3), 77.9 (Glc C-5), 77.6 (Xyl C-3), 76.1 (Glc C-2), 75.6 (Xyl C-2), 73.0 (Rha C-4), 72.1 (Rha C-4), 72.0 (Rha C-2), 71.4 (Glc C-4), 71.4 (Xyl C-4), 69.8 (Rha C-6), 69.3 (Glc C-6), 67.2 (Xyl C-5), 18.3 (Rha C-6). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [15].
Kaempferol 3-O-rutinoside (2): Yellow amorphous powder, HRESIMS m/z 617.1494 [M + Na]+ (calcd. for C27H30O15); 1H NMR (500 MHz, Methanol-d4) δH 8.05 (2H, d, J = 9.1 Hz, H-2″, 6″), 6.88 (2H, d, J = 8.7 Hz, H-3″, 5″), 6.41 (1H, d, J = 2.1 Hz, H-8), 6.22 (1H, d, J = 2.1 Hz, H-6), 5.13 (1H, d, J = 7.5 Hz, Glc H-1), 4.51 (1H, d, J = 1.4 Hz, Rha H-1), 3.82–3.32 (10H, m, Glc H-2, 6 and Rha H-2, 5), 1.12 (3H, d, J = 6.2 Hz, Rha H-6). 13C NMR (126 MHz, Methanol-d4) δC 179.4 (C-4), 166.2 (C-7), 163.0 (C-5), 161.5 (C-4’), 159.4 (C-9), 158.6 (C-2), 135.5 (C-3), 132.4 (C-2’, 6’), 122.8 (C-1’), 116.2 (C-3’, 5’), 105.7 (C-10), 104.6 (C-1″), 102.4 (C-1‴), 100.0 (C-6), 94.9 (C-8), 78.2 (C-3″), 77.2 (C-2″), 75.8 (C-5″), 73.9 (C-4‴), 72.3 (C-2‴), 72.1 (C-3‴), 71.5 (C-4″), 69.7 (C-5‴), 68.6 (C-6″), 17.9 (C-6‴). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [16].
Camelliaside B (3): Pale yellowish powder, HRESIMS m/z 749.1808 [M + Na]+ (calcd. for C32H38O19); 1H NMR (500 MHz, Methanol-d4) δH 8.07 (2H, d, J = 8.8 Hz, H-2’, 6’), 6.89 (2H, d, J = 8.6 Hz, H-3’, 5’), 6.41 (1H, d, J = 2.0 Hz, H-8), 6.22 (1H, d, J = 2.0 Hz, H-6), 5.12(1H, d, J = 7.4 Hz, Glc H-1), 4.51 (1H, d, J = 1.5 Hz, Rha H-1), 4.34 (1H, d, J = 7.6 Hz, Xyl H-1), 4.25–3.09 (15H, m), 1.10 (3H, d, J = 6.1 Hz, Rha 5-CH3). 13C NMR (126 MHz, Methanol-d4) δC 179.1 (C-4), 164.9 (C-7), 162.7 (C-5), 161.2 (C-4’), 159.1 (C-9), 158.3 (C-2), 135.1 (C-3), 132.1 (C-2’, 6’), 122.4 (C-1’), 115.8 (C-3’, 5’), 106.1 (C-10), 105.3 (Xyl C-1), 102.0 (Rha C-1), 100.2 (Glc C-1), 99.7 (C-6), 94.7 (C-8), 82.1 (Glc C-2), 77.8 (Glc C-3), 77.2 (Xyl C-3), 76.9 (Glc C-5), 75.4 (Xyl C-2), 74.3 (Rha C-4), 72.3 (Rha C-3), 72.2 (Rha C-2) 71.4 (Glc C-4), 70.8 (Xyl C-4),69.1 (Rha C-5), 68.6 (Glc C-6), 66.5 (Xyl C-5), 17.6 (Rha C-6). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [17].
Kaempferol 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside (4): Yellow powder, HRESIMS m/z 617.1607 [M + Na]+ (calcd. for C27H30O15); 1H NMR (500 MHz, Acetone-d6) δH 8.19 (2H, d, J = 8.9 Hz, H-2″, 6″), 7.01 (2H, d, J = 8.9 Hz, H-3’, 5’), 6.56 (1H, d, J = 2.1 Hz, H-8), 6.30 (1H, d, J = 2.0 Hz, H-6), 5.17 (1H, d, J = 7.4 Hz, Glc H-1), 4.59 (1H, s, Rha H-1‴), 3.87–3.29 (10H, m), 1.11 (1H, d, J = 6.2 Hz, Rha H-6‴). 13C NMR (126 MHz, Acetone-d6) δC 178.2 (C-4), 164.5 (C-7), 162.0 (C-5), 160.3 (C-4’), 157.9 (C-9), 157.2 (C-2), 134.7 (C-3), 131.4 (C-2’, 6’), 121.4 (C-1’), 115.2 (C-3’, 5’), 104.6 (C-10), 104.5 (Glc C-1″), 101.1 (Rha C-1‴), 98.9 (C-6), 93.9 (C-8), 77.4 (Glc C-3″), 75.9 (Glc C-5″), 74.7 (Rha C-4‴), 73.1 (Rha C-2‴), 72.5 (Rha C-3‴), 71.4 (Glc C-2″), 69.8 (Rha C-5‴), 67.0 (Glc C-6″), 17.2 (Rha C-6‴). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [18].
Rutin (5): Yellow powder, HRESIMS m/z 611.1770 [M + H]+ (calcd. for C27H30O16); 1H NMR (500 MHz, Methanol-d4) δH 7.65 (1H, d, J = 2.2 Hz, H-2’), 7.60 (1H, dd, J = 8.4, 2.2 Hz, H-6’), 6.85 (1H, d, J = 8.4 Hz, H-5’), 6.35 (1H, d, J = 2.1 Hz, H-6), 6.17 (1H, d, J = 2.1 Hz, H-8), 5.08 (1H, d, J = 7.5 Hz, Glc, H-1’), 4.50 (1H, d, J = 1.7 Hz, Rha, H-1’), 3.79 (1H, dd, J = 10.9, 1.5 Hz, Glc, H-6’), 3.63 (1H, dd, J = 3.4, 1.7 Hz), 3.56–3.21 (10H, m), 1.10 (3H, d, J = 6.2 Hz, Rha, H-6’). 13C NMR (126 MHz, Methanol-d4) δC 179.7 (C-4), 166.3 (C-7), 163.2 (C-5), 159.6 (C-9), 158.8 (C-2), 150.1 (C-4’), 146.1 (C-3’), 135.9 (C-3), 123.9 (C-1’), 123.4 (C-6’), 118.0 (C-5’), 116.4 (C-2’), 105.9 (C-10), 105.1 (Glc, C-1’), 102.7 (Rha, C-1’), 100.3 (C-6), 95.2 (C-8), 78.5 (Glc, C-3’), 77.5 (Glc, C-5’), 76.0 (Glc, C-2’), 74.3 (Glc, C-4’), 72.5 (Rha, C-3’), 72.4 (Rha, C-2’), 71.7 (Rha, C-4’), 70.0 (Rha, C-5’), 68.9 (Glc, C-6’), 18.2 (Rha, C-6’). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [19].
Gingerglycolipid A (6): White powder, HRESIMS m/z 675.3619 [M–H]– (calcd. for C33H56O14); 1H NMR (500 MHz, Methanol-d4) δH 5.42–5.27 (6H, m, H-9, 10, 12, 13, 15, 16), 4.60 (1H, s, H-1″), 4.29–3.45 (14H, m, H-2’, 2″, 3″, 4″, 5″, 6″, 1‴, 2‴, 3‴, 4‴, 5‴, 6‴), 2.82 (4H, t, J = 6.0 Hz, H-11, 14), 2.36 (2H, t, J = 7.5 Hz, H-2), 2.15–2.02 (2H, m, H-17), 1.62 (2H, t, J = 7.3 Hz, H-8), 1.36–1.26 (10H, m, H-3, 4, 5, 6, 7), 0.98 (3H, t, J = 7.5 Hz, H-18). 13C NMR (126 MHz, Methanol-d4) δC 175.8 (C-1), 133.1 (C-16), 131.4 (C-15), 129.6 (C-13), 129.5 (C-12), 129.2 (C-10), 128.6 (C-9), 105.7 (C-1″), 100.9 (C-1‴), 75.0 (C-3″), 74.9 (C-5″), 72.9 (C-2″), 72.9 (C-5‴), 72.4 (C-1’), 71.8 (C-3‴), 71.4 (C-4‴), 70.6 (C-2‴), 70.5 (C-4″), 70.0 (C-2’), 68.1 (C-1″), 66.9 (C-3’), 63.1 (C-6‴), 35.3 (C-2), 31.0 (C-17), 30.7 (C-14), 30.6 (C-11), 30.5 (C-8), 28.5 (C-7), 26.9 (C-6), 26.7 (C-5), 26.3 (C-4), 21.8 (C-3), 15.0 (C-18). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [20].
Solalyratin B (7): White powder, HRESIMS m/z 418.8899 [M + H]+ (calcd. for C24H34O6); 1H NMR (500 MHz, Methanol-d4) δH 7.00 (1H, d, J = 15.8 Hz, H-7′), 6.44 (1H, d, J = 15.8 Hz, H-8′), 5.94 (1H, s, C-2′), 5.75 (1H, s, C-2), 4.26–4.15 (1H, m, C-6), 2.61 (1H, d, J = 17.0 Hz, C-6′), 2.42 (1H, dd, J = 13.5, 2.7 Hz, C-5), 2.31 (3H, s, C-10′), 2.02–1.97 (1H, m, C-7), 1.90 (3H, d, J = 1.30 Hz, C-11′), 1.76 (3H, s, C-11), 1.53 (1H, dd, J = 14.4, 3.7 Hz, C-7), 1.47 (2H, s, C-9), 1.29 (3H, s, C-10), 1.07 (3H, s,C-12′), 1.02 (3H, s, C-13′). 13C NMR (126 MHz, Methanol-d4) δC 200.7 (C-9′), 200.4 (C-1′), 185.7 (C-1), 174.5 (C-3), 148.4 (C-7′), 131.7 (C-8′), 128.0 (C-2′), 113.3 (C-2), 89.0 (C-4), 80.0 (C-4′), 67.3 (C-6), 50.5 (C-6′), 48.0 (C-7), 46.5 (C-5), 42.7 (C-5′), 37.2 (C-8), 31.0 (C-10), 27.6 (C-10′), 27.4 (C-11), 27.0 (C-9), 24.7 (C-13′), 23.5 (C-1 2′), 19.2 (C-11′). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [21].
(+)-Syringaresinol (8): White columnar crystals, HRESIMS m/z 419.1768 [M + H]+ (calcd. for C22H26O8); 1H NMR (500 MHz, Methanol-d4) δH 6.66 (4H, s, H-2’, H-6,’ H-2″, H-6″), 4.71 (2H, d, J = 4.5 Hz, H-2, H-6), 4.26 (2H, dd, J = 9.0, 7.0 Hz, H-4a, H-8a), 3.88 (2H, dd, J = 9.0, 4.0 Hz, H-4b, H-8b), 3.84 (12H, s, 3’, 5’, 3″, 5″-OCH3), 3.16–3.11 (2H, m, H-1, H-5). 13C NMR (126 MHz, Methanol-d4) δC 149.5 (C-3’, 5’, 3″, 5″), 136.3 (C-4’, 4″), 133.3 (C-1’, 1″), 104.6 (C-2’, 6’, 2″, 6″), 87.8 (C-2, 6), 72.9 (C-4, 8), 56.9 (C-3’, 5’, 3″, 5″-OMe), 55.7 (C-1, 5). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [22].
(+)-Mediastinal (9): White amorphous powder, HRESIMS m/z 389.1628 [M + H]+ (calcd. for C21H24O7); 1H NMR (500 MHz, Methanol-d4) δH 6.95 (1H, d, J = 1.7 Hz, H-2), 6.82 (1H, dd, J = 1.7, 8.1 Hz, H-6), 6.77 (1H, d, J = 8.1 Hz, H-5), 6.66 (2H, s, H-2′, 6′), 4.72 (2H, m, H-7, 7′), 4.30–4.20 (2H, m, H-9, 9′), 3.86 (3H, s, 3-OMe), 3.85 (6H, s, 3′, 5′-OMe), 3.16–3.13 (2H, m, H-8, 8′). 13C NMR (126 MHz, Methanol-d4) δC 149.5 (C-3′, 5′), 149.3 (C-3), 147.5 (C-4), 136.4 (C-4′), 134.0 (C-1), 133.3 (C-1′), 120.3 (C-6), 116.3 (C-5), 111.2 (C-2), 104.7 (C-2′, 6′), 87.9 (C-7′), 87.7 (C-7), 72.9 (C-9′), 72.8 (C-9), 57.0 (3′, 5′-OMe), 56.6 (3-OMe), 55.7 (C-8), 55.5 (C-8′). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [23].
(−)-Pinoresinol (10): Colorless crystals, HRESIMS m/z 341.1444 [M–H2O + H]+ (calcd. for C20H22O6); 1H NMR (500 MHz, Methanol-d4) δH 6.95 (2H, d, J = 1.9 Hz, H-2, 2′), 6.82 (2H, dd, J = 8.2, 1.9 Hz, H-6, 6′), 6.77 (2H, d, J = 8.1 Hz, H-5, 5′), 4.71 (1H, d, J = 4.7 Hz, H-7, 7′), 4.24 (1H, dd, J = 9.1, 6.9 Hz, H-9a, 9a′), 3.86 (6H, s, 3, 3′-OMe), 3.85 (2H, s, H-9b, 9b′), 3.17–3.12 (2H, m, H-8, 8′). 13C NMR (126 MHz, Methanol-d4) δC 149.3 (C-3, 3′), 147.5 (C-4, 4′), 133.9 (C-1, 1′), 120.2 (C-6, 6′), 116.3 (C-5, 5′), 111.1 (C-2, 2′), 87.7 (C-7, 7′), 72.8 (C-9, 9′), 56.6 (2×OMe), 55.5 (C-8, 8′). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [24].
(+)-epi-Syringaldehyde (11): Colorless solid, HRESIMS m/z 441.1581 [M + Na]+ (calcd. for C22H26O8); 1H NMR (500 MHz, Methanol-d4) δH 6.95 (2H, d, J = 1.9 Hz, H-2, 2′), 6.82 (2H, dd, J = 8.2, 1.9 Hz, H-6, 6′), 6.77 (2H, d, J = 8.1 Hz, H-5, 5′), 4.71 (1H, d, J = 4.7 Hz, H-7, 7′), 4.24 (1H, dd, J = 9.1, 6.9 Hz, H-9a, 9a′), 3.86 (6H, s, 3, 3′-OMe), 3.85 (2H, s, H-9b, 9b′), 3.17–3.12 (2H, m, H-8, 8′). 13C NMR (126 MHz, Methanol-d4) δC 149.3 (C-3, 3′), 147.5 (C-4, 4′), 133.9 (C-1, 1′), 120.2 (C-6, 6′), 116.3 (C-5, 5′), 111.1 (C-2, 2′), 87.7 (C-7, 7′), 72.8 (C-9, 9′), 56.6 (2×OMe), 55.5 (C-8, 8′). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [25].
ω-Hydro-xypropioguaiacone (12): Colorless oily substance, HRESIMS m/z 195.0620 [M–H]− (calcd. for C10H12O4); 1H NMR (500 MHz, Methanol-d4) δH 7.58 (1H, dd, J = 8.3, 2.0 Hz, H-6′), 7.43 (1H, d, J = 2.0 Hz, H-2′), 6.92 (1H, d, J = 8.3 Hz, H-5′), 4.32 (3H, s, OMe) 3.93 (2H, t, J = 6.1 Hz, H-3), 3.16 (2H, t, J = 6.2 Hz, H-2). 13C NMR (126 MHz, Methanol-d4) δC 200.2 (C-1), 154.2 (C-3′),149.7 (C-4′), 131.0 (C-1′),125.3 (C-6′), 116.4 (C-5′), 112.4 (C-2′), 59.5 (C-3), 56.9 (OMe), 42.2 (C-2). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [26].
Vanillic acid (13): Colorless needle crystals, HRESIMS m/z 169.0491 [M+H]+ (calcd. for C8H8O4); 1H NMR (500 MHz, Methanol-d4) δH 7.58 (1H s Ar-H), 7.53 (1H, d, J = 8.2 Hz, Ar-H), 6.80 (1H, d, J = 8.2 Hz, Ar-H), 3.89 (3H, s, -OMe). 13C NMR (126 MHz, Methanol-d4) δC 172.2 (C-7), 151.5 (C-3), 148.4 (C-2), 124.8 (C-5), 120.4 (C-6) 115.5 (C-1), 113.9 (C-4), 56.3 (OMe). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [27].
4-Hydroxybenzaldehyde (14): Colorless oily substance, HRESIMS m/z 121.0345 [M+H]+ (calcd. for C7H6O2); 1H NMR (500 MHz, Methanol-d4) δH 9.76 (1H, s, COH), 7.77 (2H, d, J = 8.6 Hz, H-2, 6), 6.91 (2H, d, J = 8.6 Hz, H-3, 5). 13C NMR (126 MHz, Methanol-d4) δC 192.3 (-COH), 165.2 (C-4), 133.0 (C-2, 6), 129.6 (C-1), 116.5 (C-3, 5). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [28].
2-Methoxyhydroquinone (15): White powder, HRESIMS m/z 141.3576 [M + H]+ (calcd. for C7H8O3); 1H NMR (500 MHz, Methanol-d4) δH 7.59 (1H, d, J = 1.9 Hz, H-3), 7.53 (1H, dd, J = 8.2, 1.9 Hz, H-6), 6.79 (1H, d, J = 8.2 Hz, H-5), 3.89 (3H, s, 2-OMe). 13C NMR (126 MHz, Methanol-d4) δC 150.5 (C-4), 147.8 (C-2), 128.3 (C-1), 124.1 (C-6), 114.9 (C-5), 113.47 (C-3), 55.8 (2-OMe). The structures of these compounds were established via spectroscopic analysis and comparison of their NMR data with the literature [29].

2.6. Antioxidant Activity

The ABTS free radical scavenging capacity of all isolated compounds was measured, and the procedure followed a method with minor modifications [30]. The experiment was conducted using a 96-well plate, with each well containing a total volume of 210 µL. Equal volumes of ABTS solution (7 mM) and potassium persulfate solution (5 mM) were thoroughly mixed and allowed to react at room temperature for 12 h in the absence of light to generate the ABTS radical cation. The mixture was then diluted with anhydrous methanol to achieve an absorbance value of about 0.7 ± 0.02 units at 734 nm. Then, 180 µL of ABTS working solution was added to each well, followed by 30 µL samples of varying concentrations (0.5, 0.1, 0.05, 0.01 µg/mL) were dissolved and diluted with DMSO. After thorough mixing, the samples were incubated at room temperature for 6 min in a light-free environment. Subsequently, the absorbance values of each well were measured at 734 nm using a microplate reader, and the results were obtained from a minimum of three independent experiments. Ascorbic acid was employed as the positive control. DMSO was used to replace the sample solution as a blank and absolute methanol was used to replace the ABTS solution as a control. All tests were performed in triplicate, and the obtained results were processed by analysis of variance (ANOVA) with 95% confidence (p ≤ 0.05).
The percentage radical cation scavenging rate (%) of each test sample for ABTS was calculated as follows (1):
Radical cation scavenging rate (%) = [A blank − (A sample − A control)] / A blank × 100%

2.7. Antimicrobial Activity

The antibacterial activity capacity of all isolated compounds was measured, and the procedure followed a method with minor modifications [31,32]. Antimicrobial drug mother liquor preparation: dissolve the drug with DMSO, and its mass concentration was 0.5 mg/mL. Preparation of the bacterial solution to be tested: Thaw the frozen bacteria from a −80 °C low-temperature storage box at room temperature, and sterilize the Nutrient Broth (NB) medium in a 37 °C shaking bed for overnight culture. Then take 2 mL of the overnight culture of the bacterial solution and inoculate it into the NB medium. Incubate it at 37 °C until A600 = 0.5, and then dilute it 100 times with the NB medium. Micro broth dilution method: Take a sterile 96-well plate, add 75 μL of the NB medium dilution solution to the A2–A11 wells, and add 75 μL of the drug solution to the A1–A2 wells. Take 75 μL of the mixture from the A2 wells to the A3 wells, 75 μL of the mixture from the A3 wells to the A4 wells, and so on up to the A10 wells. Take up 75 μL of the mixture to the A10 wells, discard it, and add 75 μL of 5% DMSO to the 12 wells. Add 75 μL of the bacterial solution to well A12 and mix well. The inoculated 96-well plates were incubated at 37 °C for 12 h. After inoculation, the 96-well plates were incubated at 37 °C for 14 h to observe the growth. The minimum inhibitory concentration (MIC) was calculated by measuring A600 with an enzyme marker. All tests were performed in triplicate, and the obtained results were processed by (ANOVA) with 95% confidence (p ≤ 0.05).

3. Results and Discussion

3.1. Antioxidant Activity

In the ABTS assay, the antioxidant activity is measured as the ability of test compounds to decrease the color by reacting directly with the radical ABTS [33]. The antioxidant activities of all the isolates were assessed in vitro using the ABTS assay method, and the corresponding results are presented in Table 2. The results of these experiments demonstrated that compounds 5, and 8–11 exhibited superior antioxidant activity compared to the positive drug ascorbic acid, while the activities of compounds 7, 13, and 15 were comparable to that of ascorbic acid. The other compounds had weaker or no significant antioxidant activities. This finding once again confirms that flavonoids [34,35,36], terpenoids [37,38], lignans [39,40,41], and phenolic acid [42] compounds have good antioxidant activities. The compounds 1–5 are all flavonoid glycosides; however, compound 5 demonstrates significantly superior antioxidant activity in comparison to compounds 1–4. An analysis of the structure–activity relationship for these five flavonoid glycosides reveals a direct correlation between the free radical scavenging activity and the number of hydroxyl groups on the B ring. Increasing the number of hydroxyl groups on the B ring enhances the free radical scavenging activity. Moreover, it is noteworthy that C–3 possesses an alcohol hydroxyl group, which exhibits greater stability and reduced susceptibility to electron loss compared to a phenol hydroxyl group. This characteristic contributes to increased water solubility of compounds without significantly affecting their antioxidant activity. These findings are consistent with the previous literature analyses regarding the conformational relationship between flavonoid antioxidant activities [43,44,45]. Meanwhile, the antioxidant activities of compounds 1–4 also differed, which was mainly related to the number and position of hydroxyl groups and the spatial site resistance of glycosides [46]. The lignan compounds 8–11 possess two phenolic hydroxyl groups, and their antioxidant activities exhibit minimal variation among each other. This similarity may be attributed to the positive impact of the methoxy group, located adjacent to the phenolic hydroxyl group, on the antioxidant activity of lignans in the power supply [47]. Compounds 12–15 are phenolic acids derived from hydroxybenzoic acid, with compound 14 exhibiting significantly lower antioxidant activity compared to compounds 12–13 and 15. Furthermore, the introduction of o-hydroxy and o-methoxy groups enhances the antioxidant activity of phenolic acids [48]. The findings suggest that flavonoids, phenols, lignans, and terpenoids are the primary antioxidant secondary metabolites in C. fascicularis. Due to the limited quantity of certain compounds and their inadequate initial concentration of 500 µg/mL for effective antioxidant activity, experiments were not conducted on these compounds considering the requirement for subsequent sequential activity determination. The utilization of only ABTS as an indicator for assessing antioxidants may not comprehensively reflect the complete antioxidant activity of compounds.

3.2. Antibacterial Activity

The utilization of botanical extracts as natural antimicrobial agents in the food industry is an emerging trend [49]. The antimicrobial activity testing of the samples was performed against microorganism strains from the laboratory collection. The Gram-positive bacteria used for the tests were Staphylococcus aureus (ATCC 6538). The Gram-negative bacteria were Escherichia coli (ATCC 6538) and Pseudomonas aeruginosa (CGMCC 1.10712). The antimicrobial activity of C. fascicularis has not been reported, but the antimicrobial activity of researchers in Camellia proved that Camellia has good antimicrobial activity [50,51,52]. The findings provide additional evidence to substantiate the potent antibacterial activity of secondary metabolites derived from C. fascicularis.
As shown in Table 3, the results of the antimicrobial activity test showed that compounds 1–15 all showed some degree of inhibition against E. coli at 125–250 µg/mL, with compound 7 showing better antimicrobial activity than the other compounds, but still lower than the positive control drugs penicillin (MIC 31.25 µg/mL) and tetracycline (MIC 7.81 µg/mL). Compounds 3, 5–9, 11, and 14–15 showed a certain degree of inhibition of S. aureus at 125–250 µg/mL, which was still weaker compared with the positive control drug. The antibacterial activity of compounds 5, 7, 9, 11, and 13 against P. aeruginosa was comparable to that of the positive control drug tetracycline (MIC 62.50 µg/mL) and superior to that of penicillin (MIC 125.00 ug/mL), whereas the antibacterial activity of compound 15 against P. aeruginosa showed antimicrobial activity comparable to the positive control drug penicillin (MIC 125.00 µg/mL) and weaker than tetracycline (MIC 62.50 µg/mL). The findings suggest that flavonoids, phenolics, and terpenoids serve as the primary secondary metabolites responsible for the antimicrobial activity in C. fascicularis. The MIC data of 250.00 μg/mL in antibacterial activity indicates a range of true valuest from 125.00 to 500.00 μg/mL. It is important to note that this method provides an approximation rather than an absolute accurate value for the MIC. If it were possible to provide microstructures of different bacteria at optimal inhibitory concentrations and scanning electron microscopy images, it would further support our study; unfortunately, all compounds were completely consumed during the series of bioactivity assays.
The structures of the known compounds were defined as tsubakioside A (1), kaempferol 3-O-rutinoside (2), camelliaside B (3), kaempferol 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside (4), rutin (5), gingerglycolipid A (6), solalyratin B (7), (+)-syringaresinol (8), (+)-mediastinal (9), (–)-pinoresinol (10), (–)-epi-syringaldehyde (11), ω-hydro-xypropioguaiacone (12), vanillic acid (13), 4-hydroxybenzaldehyde (14), and 2-methoxyhydroquinone (15), respectively.
The presence of compounds (1–5) in the Theaceae family has been previously demonstrated through chemical studies [17,53,54], highlighting the abundant and diverse flavonoid content in Camellia. Compound 6 was initially derived from plants belonging to the genus Ginger in the Zingiberaceae family. It serves as a crucial metabolite involved in various physiological processes, including germination, growth, flowering, senescence, and fruit ripening in higher plants. Additionally, it plays a significant role in evaluating the effects of glucose-lowering [55,56,57,58]. Compound 7 is a tetraterpene with notable anti-inflammatory and anti-complementary activities. Moreover, this study demonstrates its remarkable antioxidant and antibacterial properties [21,59]. In addition, lignans (8–11) have been recognized as bioactive components with applications in the pharmaceutical and nutritional industries [60,61]. Compounds (12–15), as phenolic acids, are widely found in Theaceae plants [62,63].

4. Conclusions

Secondary metabolites investigation on the leaves of C. fascicularis afforded 15 compounds, including 5 flavonoids (1–5), a galactosylglycerol derivative (6), a terpenoid (7), 4 lignans (8–11), and 4 phenolic acids (12–15). Compounds 6–7 and 9–12 were isolated from the genus Camellia for the first time. The remaining compounds were also isolated from this plant for the first time. The antioxidant and antimicrobial activities of the isolated and obtained compounds were determined. The evaluation of antioxidant and antimicrobial activities demonstrated that compounds 5 and 8–11 exhibited superior antioxidant activity compared to the positive control drug ascorbic acid. Compounds 7, 13, and 15 displayed similar activity to ascorbic acid. In terms of antibacterial activity against P. aeruginosa, compounds 5, 7, 9, 11, and 13 showed comparable MIC values to the positive control drug tetracycline at a concentration of 62.50 µg/mL. Additionally, other secondary metabolites inhibited E. coli and S. aureus at concentrations ranging from 125–250 µg/mL. The experimental results suggested that flavonoids, phenols, lignans, and terpenoids are the main secondary metabolites of antioxidant and antibacterial activities in C. fascicularis. The results of the study enriched the variety of secondary metabolites of C. fascicularis, laid the foundation for further research on the pharmacological efficacy and biological activity of this plant, and also provided a reference and theoretical basis for the development and utilization of this plant resource.

Author Contributions

Conceptualization, J.T. (Jiandong Tang); methodology, J.T. (Jiandong Tang) and R.L.; software, J.T. (Jiandong Tang); validation, B.W., J.T. (Junrong Tang), and H.K.; formal analysis, B.W.; investigation, Y.Z. and P.Z.; resources, Y.L.; data curation, J.T. (Jiandong Tang); writing—original draft preparation, J.T. (Jiandong Tang); writing—review and editing, W.W. and Y.L.; visualization, J.T. (Jiandong Tang) and R.L.; supervision, P.Z. and W.W.; project administration, Y.L.; funding acquisition, Y.L. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the Yunnan Agricultural Basic Research Joint Special Project (202101BD070001-045), Youth Talents Special Project of Yunnan Province “Xingdian Talents Support Program” (XDYC-QNRC-2022-0222).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data presented in this study are available upon request from the corresponding author.

Acknowledgments

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Liu, Y.; Luo, X.L.; Lan, Z.Q.; Tang, J.R.; Zhao, P.; Kan, H. Ultrasonic-assisted extraction and antioxidant capacities of flavonoids from Camellia fascicularis leaves. CyTA-J. Food 2018, 16, 105–112. [Google Scholar] [CrossRef]
  2. Hu, X.; Tang, J.R.; Zhang, G.L.; Deng, J.; Kan, H.; Zhang, Y.J.; Zhao, P.; Liu, Y. Optimization of extraction process and antioxidant activities of saponins from Camellia fascicularis leaves. J. Food Meas. Charact. 2021, 15, 1889–1898. [Google Scholar] [CrossRef]
  3. Liu, Y.; Kan, H.; Fang, F.Y.; Tang, J.R.; Zhang, Y.J.; Zhao, P. Microwave-assisted extraction and antioxidant activities of polyphenols from Camellia fascicularis leaves. Curr. Top. Nutraceut. Res. 2019, 17, 164–171. [Google Scholar] [CrossRef]
  4. Song, L.X.; Wang, X.S.; Zheng, X.Q.; Huang, D.J. Polyphenolic antioxidant profiles of yellow Camellia. Food Chem. 2011, 129, 351–357. [Google Scholar] [CrossRef] [PubMed]
  5. Peng, X.; Yu, D.Y.; Feng, B.M.; Wang, Y.Q.; Shi, L.Y. A new acylated flavonoid glycoside from the flowers of Camellia nitidissima and its effect on the induction of apoptosis in human lymphoma U937 cells. J. Asian Nat. Prod. Res. 2012, 14, 799–804. [Google Scholar] [CrossRef]
  6. Gao, D.F.; Xu, M.; Zhao, P.; Zhang, X.Y.; Wang, Y.F.; Yang, C.R.; Zhang, Y.J. Kaempferol acetylated glycosides from the seed cake of Camellia oleifera. Food Chem. 2011, 124, 432–436. [Google Scholar] [CrossRef]
  7. Chen, J.H.; Wu, X.H. Extraction process optimization of saponin from the leaves of Camellia nitidissima Chi and its inhibition of lipase activity. Food Mach. 2020, 36, 159–165. [Google Scholar] [CrossRef]
  8. Peng, X.; Yu, D.Y.; Feng, B.M.; Tang, L.; Wang, Y.Q.; Shi, L.Y. Chemical constituents from the flowers of Camellia chrysantha. Guihaia 2011, 31, 550–553. [Google Scholar] [CrossRef]
  9. He, X.H.; Shi, Z.J.; Peng, X.W.; Kan, H.; Zhao, P.; Liu, Y. Antioxidant activities analysis of different polar solvent extracts from Camellia fascicularis H T. Chang. Chem. Ind. For. Prod. 2022, 42, 61–68. [Google Scholar] [CrossRef]
  10. Peng, X.W.; He, X.H.; Tang, J.R.; Xiang, J.Y.; Deng, J.; Kan, H.; Zhang, Y.J.; Zhang, G.L.; Zhao, P.; Liu, Y. Evaluation of the in vitro antioxidant and antitumor activity of extracts from Camellia fascicularis leaves. Front. Chem. 2022, 10, 1035949. [Google Scholar] [CrossRef]
  11. Peng, X.W.; Hu, X.; Zhang, Y.J.; Xu, H.; Tang, J.R.; Zhang, G.L.; Deng, J.; Kan, H.; Zhao, P.; Liu, Y. Extraction, characterization, antioxidant and anti-tumor activities of polysaccharides from Camellia fascicularis leaves. Int. J. Biol. Macromol. 2022, 222, 373–384. [Google Scholar] [CrossRef] [PubMed]
  12. Gao, M.Z.; Peng, X.W.; Tang, J.R.; Deng, J.; Wang, F.; Zhang, Y.J.; Zhao, P.; Kan, H.; Liu, Y. Anti-inflammatory effects of Camellia fascicularis polyphenols via attenuation of NF-κB and MAPK pathways in LPS-induced THP-1 macrophages. J. Iinflamm. Res. 2022, 15, 851–864. [Google Scholar] [CrossRef] [PubMed]
  13. Gao, M.Z.; Tang, J.R.; Deng, J.; Xiang, J.Y.; Kan, H.; Zhao, P.; Zhang, Y.J.; Zhang, G.L.; Liu, Y. Evaluation of anti-inflammatory effect of Camellia fascicularis polyphenols using zebrafish model and network pharmacology. Food Sci. 2023, 44, 134–142. [Google Scholar] [CrossRef]
  14. Takahashi, J.A.; Gomes, D.C.; Lyra, F.H.; Santos, G.F.; Martins, L.R. The remarkable structural diversity achieved in ent-kaurane diterpenes by fungal biotransformation. Molecules 2014, 19, 1856–1886. [Google Scholar] [CrossRef]
  15. Sato, N.; Li, W.; Tsubaki, M.; Higai, K.; Takemoto, M.; Sasaki, T.; Onoda, T.; Suzuki, T.; Koike, K. Flavonoid glycosides from Japanese Camellia oil cakes and their inhibitory activity against advanced glycation end-products formation. J. Funct. Foods 2017, 35, 159–165. [Google Scholar] [CrossRef]
  16. Parveen, A.; Farooq, M.A.; Kyunn, W.W. A new oleanane type saponin from the aerial parts of Nigella sativa with anti-oxidant and anti-diabetic potential. Molecules 2020, 25, 2171. [Google Scholar] [CrossRef] [PubMed]
  17. Ko, J.; Rho, T.; Yoon, K.D. Kaempferol tri-and tetrasaccharides from Camellia japonica seed cake and their inhibitory activities against matrix metalloproteinase-1 secretion using human dermal fibroblasts. Carbohyd. Res. 2020, 495, 108101. [Google Scholar] [CrossRef]
  18. Wu, H.; Dushenkov, S.; Ho, C.T.; Sang, S.M. Novel acetylated flavonoid glycosides from the leaves of Allium ursinum. Food Chem. 2009, 115, 592–595. [Google Scholar] [CrossRef]
  19. Liu, L.; Chang, X.J.; Dai, Q.J.; Wang, H.Y.; Chen, J.; Zhang, X.W. Bioactivity-guided isolation of anti-acetylcholinesterase compounds from Odontites vulgaris Moench. Med. Chem. Res. 2023, 32, 2349–2355. [Google Scholar] [CrossRef]
  20. Yuan, Y.; Rouzimaimait, R.; Hasan, A.; Zeng, D.; Aisa, H.A. A new anti-vitiligo unsaturated fatty glycoside from Euphorbia humifusa Willd. Nat. Prod. Res. 2023, 37, 2225–2231. [Google Scholar] [CrossRef]
  21. Zhang, D.W.; Yang, Y.; Yao, F.; Yu, Q.Y.; Dai, S.J. Solalyratins A and B, new anti-inflammatory metabolites from Solanum lyratum. J. Nat. Med. 2012, 66, 362–366. [Google Scholar] [CrossRef] [PubMed]
  22. Xu, Y.L.; Xu, Y.J.; Shi, H.X.; Liu, Y.; Xu, T.H. Lignanoids from Solanum lyratum. J. Chin. Pharm. Sci. 2018, 27, 289–294. [Google Scholar] [CrossRef]
  23. Aung, H.T.; Saw, K.T.; Latt, M.M.; Vidari, G.; Komori, Y.; Takaya, Y. Lignans and coumarins from the stem bark of Alyxia fascicularis (Wall. ex G. Don) Benth. ex Hook. f. Nat. Prod. Res. 2024, 38, 1616–1623. [Google Scholar] [CrossRef]
  24. Xu, W.Z.; Jin, H.Z.; Zhang, W.D.; Fu, J.J.; Hu, X.J.; Zhang, W.; Yan, S.K.; Shen, Y.H. Studies on the chemical constituents of Daphne pedunculata. Chem. Nat. Compd. 2008, 44, 771–772. [Google Scholar] [CrossRef]
  25. Hu, B.; Khutsishvili, M.; Fayvush, G.; Atha, D.; Borris, R.P. Phytochemical investigations and antimicrobial activities of Anchusa azurea. Chem. Nat. Compd. 2020, 56, 119–121. [Google Scholar] [CrossRef]
  26. Shataer, D.; Abdulla, R.; Ma, Q.L.; Liu, G.Y.; Aisa, H.A. Chemical composition of extract of Corylus avellana Shells. Chem. Nat. Compd. 2020, 56, 338–340. [Google Scholar] [CrossRef]
  27. Xie, G.Q.; Zhao, G.S.; Pei, S.C.; Zheng, Y.P.; Zang, H.; Li, L. Isolation and identification of active ingredients and biological activity of Dioscorea nipponica makino. BMC Complement. Med. 2023, 23, 240. [Google Scholar] [CrossRef]
  28. Ge, L.L.; Xie, Q.J.; Wei, X.F.; Li, Y.F.; Shen, W.Y.; Hu, Y.G.; Yao, J.; Wang, S.L.; Du, X.; Zeng, X.B. Five undescribed plant-derived bisphenols from Artemisia capillaris aerial parts: Structure elucidation, anti-hepatoma activities and plausible biogenetic pathway. Arab. J. Chem. 2023, 16, 104580. [Google Scholar] [CrossRef]
  29. Zhao, Y.; Tao, M.H.; Chen, Y.C.; Yu, J.P.; Zhang, W.M. Isolation and identification of secondary metabolites from the solid culture of endophytic fungal strain Botryosphaeria rhodina A13 from Aquilaria sinensis. Nat. Prod. Res. Dev. 2015, 27, 799–803. [Google Scholar] [CrossRef]
  30. Sridhar, K.; Charles, A.L. In vitro antioxidant activity of Kyoho grape extracts in DPPH and ABTS assays: Estimation methods for EC50 using advanced statistical programs. Food Chem. 2019, 275, 41–49. [Google Scholar] [CrossRef]
  31. Rivero-Cruz, J.F.; Granados-Pineda, J.; Pedraza-Chaverri, J.; Perez-Rojas, J.M.; Kumar-Passari, A.; Diaz-Ruiz, G.; Rivero-Cruz, B.E. Phytochemical constituents, antioxidant, cytotoxic, and antimicrobial activities of the ethanolic extract of Mexican Brown Propolis. Antioxidants 2020, 9, 70. [Google Scholar] [CrossRef] [PubMed]
  32. Wang, Y.J.; Huang, J.M.; Wen, C.; Zhou, Z.S.; Feng, C.C.; Hu, C.H.; Zhou, P.F.; Yin, G.P. Chemical constituents from whole herb of Hedyotis scandens. China J. Chin. Mater. Med. 2023, 48, 6082–6087. [Google Scholar] [CrossRef]
  33. Prior, R.L.; Wu, X.; Schaich, K. Standardized methods for the determination of antioxidant capacity and phenolics in foods and dietary supplements. J. Agric. Food Chem. 2005, 53, 4290–4302. [Google Scholar] [CrossRef] [PubMed]
  34. Xu, H.; Yu, S.L.; Lin, C.X.; Dong, D.J.; Xiao, J.B.; Ye, Y.B.; Wang, M.F. Roles of flavonoids in ischemic heart disease: Cardioprotective effects and mechanisms against myocardial ischemia and reperfusion injury. Phytomedicine 2024, 126, 155409. [Google Scholar] [CrossRef] [PubMed]
  35. Li, H.; Lin, J.; Bai, B.; Bo, T.; He, Y.; Fan, S.; Zhang, J. Study on purification, identification and antioxidant of flavonoids extracted from Perilla leaves. Molecules 2023, 28, 7273. [Google Scholar] [CrossRef] [PubMed]
  36. Xi, J.; Yan, L.L. Optimization of pressure-enhanced solid-liquid extraction of flavonoids from Flos Sophorae and evaluation of their antioxidant activity. Sep. Purif. Technol. 2017, 175, 170–176. [Google Scholar] [CrossRef]
  37. Lachowicz, S.; Seliga, Ł.; Pluta, S. Distribution of phytochemicals and antioxidative potency in fruit peel, flesh, and seeds of Saskatoon berry. Food Chem. 2020, 305, 125430. [Google Scholar] [CrossRef] [PubMed]
  38. Hu, Y.J.; Chen, M.L.; Liang, D. Lignans and terpenoids from Gaultheria leucocarpa var. yunnanensis and their anti-inflammatory and antioxidant activities. Fitoterapia 2022, 162, 105293. [Google Scholar] [CrossRef] [PubMed]
  39. Jang, W.Y.; Kim, M.-Y.; Cho, J.Y. Antioxidant, anti-inflammatory, anti-menopausal, and anti-cancer effects of lignans and their metabolites. Int. J. Mol. Sci. 2022, 23, 15482. [Google Scholar] [CrossRef]
  40. Ul’yanovskii, N.V.; Onuchina, A.A.; Faleva, A.V.; Gorbova, N.S.; Kosyakov, D.S. Comprehensive characterization of chemical composition and antioxidant activity of lignan-rich coniferous knotwood extractives. Antioxidants 2022, 11, 2338. [Google Scholar] [CrossRef]
  41. Vek, V.; Keržič, E.; Poljanšek, I.; Eklund, P.; Humar, M.; Oven, P. Wood extractives of silver fir and their antioxidant and antifungal properties. Molecules 2021, 26, 6412. [Google Scholar] [CrossRef]
  42. Zhang, M.; Shuai, X.X.; Wei, Z.; Dai, T.T.; Wei, C.B.; Li, Y.; He, J.J.; Du, L.Q. Characterization, antioxidant and antitumor activities of phenolic compounds from Amomum villosum Lour. Front. Nutr. 2024, 11, 1327164. [Google Scholar] [CrossRef]
  43. Li, K.; Fan, H.; Yin, P.P.; Yang, L.G.; Xue, Q.; Li, X.; Sun, L.W.; Liu, Y.J. Structure-activity relationship of eight high content flavonoids analyzed with a preliminary assign-score method and their contribution to antioxidant ability of flavonoids-rich extract from Scutellaria baicalensis shoots. Arab. J. Chem. 2018, 11, 159–170. [Google Scholar] [CrossRef]
  44. Zhang, Q.; Yang, W.B.; Liu, J.C.; Liu, H.; Zhang, C.L.; Chen, D.L.; Jian, Z.G. Identification of six flavonoids as novel cellular antioxidants and their structure-activity relationship. Oxid. Med. Cell. Longev. 2020, 2020, 4150897. [Google Scholar] [CrossRef]
  45. Yang, T.; Zhang, Z.; Ning, F.; Yuan, L.; Yang, X.; Luo, L. New theoretical perspective for easy evaluation of the antioxidant properties of typical flavonoids. Microchem. J. 2024, 197, 109786. [Google Scholar] [CrossRef]
  46. Tao, Y.; Zhang, H.; Wang, Y. Revealing and predicting the relationship between the molecular structure and antioxidant activity of flavonoids. LWT Food Sci. Technol. 2023, 174, 114433. [Google Scholar] [CrossRef]
  47. Zhang, X.; Xu, J.K.; Wang, N.L.; Su, Y.B.; Yao, X.S. Antioxidant phenanthrenes and lignans from Denderobium nobile. J. Chin. Pharm. Sci. 2008, 17, 314–318. [Google Scholar]
  48. Chen, J.X.; Yang, J.; Ma, L.L.; Li, J.; Shahzad, N.; Kim, C.K. Structure-antioxidant activity relationship of methoxy, phenolic hydroxyl, and carboxylic acid groups of phenolic acids. Sci. Rep. 2020, 10, 2611. [Google Scholar] [CrossRef] [PubMed]
  49. Soltan, O.I.A.; Gazwi, H.S.S.; Ragab, A.E.; Aljohani, A.S.M.; El-Ashmawy, I.M.; Batiha, G.E.S.; Hafiz, A.A.; Abdel-Hameed, S.M. Assessment of bioactive phytochemicals and utilization of Rosa canina fruit extract as a novel natural antioxidant for mayonnaise. Molecules 2023, 28, 3350. [Google Scholar] [CrossRef] [PubMed]
  50. Zhao, Y.; Su, R.Q.; Zhang, W.T.; Yao, G.L.; Chen, J. Antibacterial activity of tea saponin from Camellia oleifera shell by novel extraction method. Ind. Crop. Prod. 2020, 153, 112604. [Google Scholar] [CrossRef]
  51. Goulas, V.; Exarchou, V.; Kanetis, L.; Gerothanassis, I.P. Evaluation of the phytochemical content, antioxidant activity and antimicrobial properties of mountain tea (Sideritis syriaca) decoction. J. Funct. Foods 2014, 6, 248–258. [Google Scholar] [CrossRef]
  52. Keller, A.C.; Weir, L.T.; Broeckling, D.C.; Ryan, E.P. Antibacterial activity and phytochemical profile of fermented Camellia sinensis (fuzhuan tea). Food Res. Int. 2013, 53, 945–949. [Google Scholar] [CrossRef]
  53. Morikawa, T.; Ninomiya, K.; Miyake, S.; Miki, Y.; Okamoto, M.; Yoshikawa, M.; Muraoka, O. Flavonol glycosides with lipid accumulation inhibitory activity and simultaneous quantitative analysis of 15 polyphenols and caffeine in the flower buds of Camellia sinensis from different regions by LCMS. Food Chem. 2013, 140, 353–360. [Google Scholar] [CrossRef] [PubMed]
  54. Yang, B.; Liu, H.; Yang, J.; Gupta, V.K.; Jiang, Y. New insights on bioactivities and biosynthesis of flavonoid glycosides. Trends Food Sci. Tech. 2018, 79, 116–124. [Google Scholar] [CrossRef]
  55. Yoshikawa, M.; Yamaguchi, S.; Kunimi, K.; Matuda, H.; Yamahara, J. Stomachic principles in Ginger. III. An anti-ulcer principle, 6-gingesulfonic acid, and three monoacyldigalactosylglycerols, gingerglycolipids A, B, and C, from Zingiberis Rhizoma originating in Taiwan. Chem. Pharm. Bull. 1994, 42, 1226–1230. [Google Scholar] [CrossRef] [PubMed]
  56. Guevara, L.; Domínguez-Anaya, M.Á.; Ortigosa, A.; González-Gordo, S.; Díaz, C.; Vicente, F.; Corpas, F.J.; Pérez del Palacio, J.; Palma, J.M. Identification of Compounds with Potential Therapeutic uses from sweet pepper (Capsicum annuum L.) fruits and their modulation by nitric oxide (NO). Int. J. Mol. Sci. 2021, 22, 4476. [Google Scholar] [CrossRef] [PubMed]
  57. Yu, R.; Luo, J.; Liu, L.; Peng, X. Hypoglycemic effect of edible fungi polysaccharides depends on their metabolites from the fermentation of human fecal microbiota. Foods 2024, 13, 97. [Google Scholar] [CrossRef] [PubMed]
  58. Baek, J.G.; Park, D.H.; Vu, N.K.; Muvva, C.; Hwang, H.; Song, S.; Lee, H.S.; Kim, T.J.; Kwon, H.C.; Park, K.; et al. Glycolipids derived from the korean endemic plant Aruncus aethusifoliu inducing glucose uptake in mouse skeletal muscle C2C12 cells. Plants 2024, 13, 608. [Google Scholar] [CrossRef]
  59. Wang, H.; Cong, W.L.; Fu, Z.L.; Chen, D.F.; Wang, Q. Anti-complementary constituents of Viola kunawarensis. Nat. Prod. Res. 2017, 31, 2312–2315. [Google Scholar] [CrossRef]
  60. Szakiel, A.; Voutquenne-Nazabadioko, L.; Henry, M. Separation and structural analysis of lignan glycoside isolated from Vaccinium myrtillus L. rhizomes. Planta Med. 2008, 74, PB117. [Google Scholar] [CrossRef]
  61. Wu, H.Y.; Ke, J.P.; Wang, W.; Kong, Y.S.; Zhang, P.; Ling, T.J.; Bao, G.H. Discovery of neolignan glycosides with acetylcolinesterase inhibitory activity from Huangjinya green tea guided by ultra performance liquid chromatography–tandem mass spectrometry data and Global Natural Product Social molecular networking. J. Agric. Food Chem. 2019, 67, 11986–11993. [Google Scholar] [CrossRef] [PubMed]
  62. Fernandes, C.; Sousa-Baptista, J.; Lenha-Silva, A.F.; Calheiros, D.; Correia, E.; Figueirinha, A.; Salgueiro, L.; Gonçalves, T. Azorean black tea (Camellia sinensis) antidermatophytic and fungicidal properties. Molecules 2023, 28, 7775. [Google Scholar] [CrossRef]
  63. Rahman, M.J.; Camargo, A.C.; Shahidi, F. Phenolic profiles and antioxidant activity of defatted camelina and sophia seeds. Food Chem. 2018, 240, 917–925. [Google Scholar] [CrossRef]
Cimb 46 00404 g001
Figure 1. Flow chart for the isolation and purification of compounds 1–15.
Figure 1. Flow chart for the isolation and purification of compounds 1–15.
Cimb 46 00404 g001
Cimb 46 00404 g002
Figure 2. Structures of compounds 1–15.
Figure 2. Structures of compounds 1–15.
Cimb 46 00404 g002
Table 1. Weight in (Fr. A–I) of C. fasciculata.
Table 1. Weight in (Fr. A–I) of C. fasciculata.
Fractions (g)
A1 B*DEFGHIFr. II–III
6.162.614.527.165.639.532.815.7344.15/45.00
“1 B*” was obtained by combining the B and C fractions.
Table 2. Antioxidant activities of chemical constituents 1–15 in C. fascicularis.
Table 2. Antioxidant activities of chemical constituents 1–15 in C. fascicularis.
CompoundABTS+ B Assay (%)
500 µg/mL100 µg/mL50 µg/mL10 µg/mL
149.84 ± 1.88 e---
243.23 ± 2.54 f---
342.73 ± 1.81 f---
466.40 ± 1.17 d---
599.07 ± 0.49 a98.75 ± 0.22 a85.90 ± 1.0 b15.59 ± 3.21 f
620.12 ± 1.09 i---
790.81 ± 0.90 b70.08 ± 3.86 b39.61 ± 2.73 e-
899.85 ± 0.65 a99.89 ± 0.14 a98.31 ± 1.22 a21.59 ± 0.14 cde
998.66 ± 0.84 a99.20 ± 0.74 a97.88 ± 1.11 a36.61 ± 0.42 a
1099.48 ± 0.46 a99.82 ± 0.24 a86.74 ± 1.54 b26.25 ± 0.53 b
1199.40 ± 0.61 a99.32 ± 0.27 a98.36 ± 0.34 a22.28 ± 2.72 cd
12100.16 ± 0.90 a99.47 ± 0.76 a87.82 ± 1.38 b19.91 ± 1.54 de
1387.22 ± 1.23 c63.87 ± 2.13 c54.63 ± 2.14 d-
1440.18 ± 0.69 g---
1597.69 ± 3.54 a58.11 ± 2.46 d44.02 ± 4.27 e18.54 ± 1.44 ef
A ascorbic acid-99.85 ± 0.03 a61.78 ± 0.69 c25.00 ± 2.06 bc
“A” positive control; “B” inhibition ratio, “-” indicates that the experiment was not performed. Values accompanied by different letters are significantly different (p ≤ 0.05).
Table 3. Antibacterial activity of chemical components 1–15 in C. fascicularis.
Table 3. Antibacterial activity of chemical components 1–15 in C. fascicularis.
CompoundMIC b µg/mL
E. coliS. aureusP. aeruginosa
1250.00--
2250.00--
3250.00250.00-
4250.00--
5250.00250.0062.50
6250.00250.00-
7125.00250.0062.50
8250.00250.00-
9250.00250.0062.50
10250.00--
11250.00125.0062.50
12250.00--
13250.00-62.50
14250.00250.00-
15250.00250.00125.00
a Penicillin31.2531.25125.00
a Tetracycline7.8115.6362.50
“a” positive control; “b” minimum inhibitory concentration. “-” indicates that the experiment was not performed.
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Tang, J.; Li, R.; Wu, B.; Tang, J.; Kan, H.; Zhao, P.; Zhang, Y.; Wang, W.; Liu, Y. Secondary Metabolites with Antioxidant and Antimicrobial Activities from Camellia fascicularis. Curr. Issues Mol. Biol. 2024, 46, 6769-6782. https://doi.org/10.3390/cimb46070404

AMA Style

Tang J, Li R, Wu B, Tang J, Kan H, Zhao P, Zhang Y, Wang W, Liu Y. Secondary Metabolites with Antioxidant and Antimicrobial Activities from Camellia fascicularis. Current Issues in Molecular Biology. 2024; 46(7):6769-6782. https://doi.org/10.3390/cimb46070404

Chicago/Turabian Style

Tang, Jiandong, Ruonan Li, Boxiao Wu, Junrong Tang, Huan Kan, Ping Zhao, Yingjun Zhang, Weihua Wang, and Yun Liu. 2024. "Secondary Metabolites with Antioxidant and Antimicrobial Activities from Camellia fascicularis" Current Issues in Molecular Biology 46, no. 7: 6769-6782. https://doi.org/10.3390/cimb46070404

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