Phytosynthesis of Biological Active Silver Nanoparticles Using Echinacea purpurea L. Extracts
Abstract
:1. Introduction
2. Materials and Methods
2.1. Vegetal Material
2.2. Obtaining of Natural Extracts
2.3. Characterization of Natural Extracts
2.4. Phytosynthesis and Characterization of Silver Nanoparticles
2.5. Evaluation of Antioxidant Properties
2.6. Evaluation of Antimicrobial Properties
2.7. Statistical Analysis and Data Representation
3. Results
3.1. Extract Characterization
3.2. Characterization of Nanoparticles
3.3. Evaluation of Antioxidant and Antimicrobial Properties
4. Discussion
4.1. Main Findings
4.2. Implications
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Extract Used | Extract Concentration (mg/mL) | NP Encoding |
---|---|---|
Classical temperature extract (Ee) | 5.00 | EE5 |
2.50 | EE2.5 | |
2.00 | EE2 | |
1.25 | EE1.25 | |
1.00 | EE1 | |
Microwave-assisted obtained extract (Emw) | 5.00 | EM5 |
2.50 | EM2.5 | |
2.00 | EM2 | |
1.25 | EM1.25 | |
1.00 | EM1 |
Extract/Parameter | Ee | Emw |
---|---|---|
TPC (μg GAE/g extract) | 790.23 ± 12.51 a | 672.25 ± 14.83 b |
TF (mg RE/g extract) | 71.54 ± 0.53 b | 72.82 ± 0.44 a |
Catechin (mg/g) | 51.008 ± 1.551 b | 55.004 ± 1.752 a |
Epicatechin (mg/g) | 25.059 ± 0.421 b | 26.728 ± 0.371 a |
Coumaric acid (mg/g) | 0.013 ± 0.001 b | 0.029 ± 0.001 a |
Hyperoside (mg/g) | 211.96 ± 4.547 b | 252.45 ± 4.318 a |
Rutin (mg/g) | 0.228 ± 0.009 b | 0.623 ± 0.016 a |
Naringin (mg/g) | 0.166 ± 0.004 b | 0.225 ± 0.01 a |
Malvidin (mg/g) | 121.92 ± 1.221 a | 113.99 ± 1.891 b |
Genistein (mg/g) | 0.273 ± 0.01 a | 0.152 ± 0.006 b |
Gallic acid | N.D. | N.D. |
Caffeic acid | N.D. | N.D. |
Chlorogenic acid | N.D. | N.D. |
Naringenin | N.D. | N.D. |
Time | Ee Samples | Emw Samples | ||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
EE5 | EE2.5 | EE2 | EE1.25 | EE1 | EM5 | EM2.5 | EM2 | EM1.25 | EM1 | |||||||||||
Pmax (nm) | DNP (nm) | Pmax (nm) | DNP (nm) | Pmax (nm) | Pmax (nm) | DNP (nm) | Pmax (nm) | DNP (nm) | Pmax (nm) | Pmax (nm) | DNP (nm) | Pmax (nm) | DNP (nm) | Pmax (nm) | DNP (nm) | Pmax (nm) | DNP (nm) | Pmax (nm) | DNP (nm) | |
20 h | - | - | 481 | 78 | 460 | 68 | 460 | 67 | 485 | 79 | 482 | 77 | - | - | - | - | 459 | 66 | 474 | 76 |
40 h | 471 | 75 | 475 | 76 | - | - | 458 | 66 | - | - | 470 | 73 | 470 | 73 | - | - | 455 | 64 | - | - |
60 h | 470 | 73 | - | - | 459 | 66 | - | - | 456 | 64 | - | - | 455 | 64 | 454 | 63 | - | - | 454 | 63 |
112 h | 446 | 57 | 461 | 67 | - | - | 453 | 62 | - | - | 455 | 64 | 453 | 62 | - | - | 439 | 49 | - | - |
132 h | - | - | - | - | 444 | 55 | - | - | 440 | 50 | - | - | - | - | 441 | 51 | - | - | 433 | 45 |
136 h | 444 | 55 | 459 | 66 | - | - | 450 | 60 | - | - | 455 | 64 | 448 | 58 | - | - | 437 | 48 | - | - |
156 h | - | - | - | - | 442 | 53 | - | - | 435 | 47 | - | - | - | - | 439 | 49 | - | - | 431 | 42 |
184 h | 442 | 54 | 451/392 | 61 | - | - | 444 | 55 | - | - | 455 | 64 | 443 | 54 | - | - | 435 | 47 | - | - |
204 h | - | - | - | - | 443 | 54 | - | - | 428 | 42 | - | - | - | - | 437 | 48 | - | - | 430 | 41 |
9 months | 423 | 40 | 439 | 49 | 423 | 40 | 442 | 53 | 420 | 33 | 448 | 58 | 432 | 44 | 420 | 33 | 434 | 47 | 421 | 35 |
Sample | P1 | SP1 | % P1 | P2 | SP2 | % P2 | P3 | SP3 | % P3 | Average | PdI | DLS Observations |
---|---|---|---|---|---|---|---|---|---|---|---|---|
EM5 | 347.5 | 594.8 | 94.8 | 18.27 | 3.945 | 5.2 | 116.9 | 0.457 | Bimodal, reproducible | |||
EM2.5 | 111.9 | 68.62 | 77.2 | 18.14 | 5.72 | 20.5 | 4397 | 922.6 | 2.2 | 49.53 | 0.532 | Bimodal, reproducible, contains large aggregates |
EM2 | 95.37 | 62.55 | 93.4 | 6.358 | 1.623 | 6.6 | 52.35 | 0.474 | Bimodal, reproducible, polydisperse | |||
EM1.25 | 62.12 | 21.94 | 84.2 | 7.617 | 1.675 | 15.8 | 37.38 | 0.455 | Bimodal, reproducible | |||
EM1 | 68.22 | 33.75 | 87.3 | 7.540 | 2.621 | 7.54 | 36.37 | 0.469 | Monomodal, reproducible | |||
EE5 | 109.7 | 58.14 | 84 | 14.77 | 5.385 | 9.4 | 4233 | 992.6 | 5.9 | 71.55 | 0.436 | Monomodal, reproducible, polydisperse, contains large aggregates |
EE2.5 | 86.55 | 38.26 | 94.8 | 9.506 | 3.142 | 5.2 | 64.64 | 0.285 | Bimodal, reproducible, polydisperse | |||
EE2 | 75.71 | 33.87 | 87.5 | 11.80 | 3.745 | 8.2 | 3.476 | 0.817 | 4.3 | 42.13 | 0.498 | Bimodal, reproducible, polydisperse |
EE1.25 | 96.86 | 59.40 | 78.9 | 14.22 | 4.471 | 19.5 | 4.243 | 1.139 | 1.6 | 36.70 | 0.585 | Bimodal, reproducible, polydisperse |
EE1 | 69.13 | 28.71 | 84.2 | 7.07 | 1.997 | 15.8 | 33.0 | 0.570 | Bimodal, reproducible |
Sample | (111) Peak Position (Degrees) | (220) Peak Position (Degrees) | (311) Peak Position (Degrees) | FWHM (Degrees) 1 | Crystallite Dimension (nm) 1 |
---|---|---|---|---|---|
EE5 | 37.97 | 64.92 | 77.99 | 2.243 | 3.91 |
EE2.5 | 38.12 | 64.03 | 77.88 | 2.169 | 4.05 |
EE2 | 38.10 | 64.25 | 77.96 | 2.289 | 3.83 |
EE1.25 | 38.05 | 64.62 | - | 2.584 | 3.40 |
EE1 | 38.10 | 64.32 | 77.43 | 2.788 | 3.15 |
EM5 | 38.17 | 65.45 | 77.04 | 2.032 | 4.32 |
EM2.5 | 38.10 | 64.41 | 77.23 | 1.345 | 6.52 |
EM2 | 38.04 | 64.52 | 77.43 | 2.306 | 3.80 |
EM1.25 | 38.04 | 64.27 | - | 2.307 | 3.80 |
EM1 | 38.33 | 64.90 | 77.21 | 2.652 | 3.31 |
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Fierascu, I.C.; Fierascu, I.; Baroi, A.M.; Ungureanu, C.; Ortan, A.; Avramescu, S.M.; Somoghi, R.; Fierascu, R.C.; Dinu-Parvu, C.E. Phytosynthesis of Biological Active Silver Nanoparticles Using Echinacea purpurea L. Extracts. Materials 2022, 15, 7327. https://doi.org/10.3390/ma15207327
Fierascu IC, Fierascu I, Baroi AM, Ungureanu C, Ortan A, Avramescu SM, Somoghi R, Fierascu RC, Dinu-Parvu CE. Phytosynthesis of Biological Active Silver Nanoparticles Using Echinacea purpurea L. Extracts. Materials. 2022; 15(20):7327. https://doi.org/10.3390/ma15207327
Chicago/Turabian StyleFierascu, Ioana Catalina, Irina Fierascu, Anda Maria Baroi, Camelia Ungureanu, Alina Ortan, Sorin Marius Avramescu, Raluca Somoghi, Radu Claudiu Fierascu, and Cristina Elena Dinu-Parvu. 2022. "Phytosynthesis of Biological Active Silver Nanoparticles Using Echinacea purpurea L. Extracts" Materials 15, no. 20: 7327. https://doi.org/10.3390/ma15207327