Phenolic acid composition, antioxidant and antimicrobial activities of green gram (vigna radiata) exudate, husk, and germinated seed of different stages

Exploration of potent antimicrobial and antioxidant bioactive compounds of selected medicinal plants against drug-resistant pathogens

Antibiotic resistance is an escalating universal health threat in this modern era, driving the need for innovative therapeutic solutions. Medicinal plants extensively utilized in Ayurveda, offer significant promises as antibacterial agents. This study examines the metabolite composition of methanol crude extracts from Datura metel and Phyllanthus amarus and evaluates their antibacterial and antioxidant properties. The metabolite content of the crude extracts from the leaves of selected plants was investigated and characterized using HPLC and GC-MS techniques. The agar well diffusion method was used to evaluate antibacterial activity against eight pathogenic bacterial strains, and antioxidant activity was measured using the DPPH assay. Among the tested crude extracts, Datura metel exhibited the strongest antibacterial activity against Salmonella typhi, Acinetobacter baumannii, Klebsiella pneumoniae, and methicillin-resistant Staphylococcus aureus (MRSA). Phyllanthus amarus showed notable activity against Salmonella typhi, Acinetobacter baumannii, methicillin-susceptible Staphylococcus aureus (MSSA), and Klebsiella pneumoniae. The extracts exhibited antimicrobial activity against the tested organisms, with the average diameter of the zone of inhibition ranging from 19 to 21 mm and the two leaf extracts exhibited varying degrees of antibacterial activity. In antioxidant assays, the Datura metel extract demonstrated superior activity, with 78.3 ± 2% inhibition and an IC50 value of 40.1 ± 4 µg/mL. These findings highlight Datura metel and Phyllanthus amarus as promising sources of natural antibacterial and antioxidants, offering potential applications in managing infectious diseases.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-025-04228-2.

Antioxidant, antidiabetic, and antimicrobial efficacy of germinated Ocimum gratissimum and Ocimum basilicum seed

BACKGROUND

The edible seeds of Ocimum gratissimum and Ocimum basilicum were found to be a potent source of phytochemicals with noteworthy antioxidant, antidiabetic, and antimicrobial properties. This study aimed to investigate the impact of germination and extraction solvents (ethanol (EtOH), distilled water) on the therapeutic properties exhibited and the ability of seed extracts to act as natural food preservatives.

RESULTS

The EtOH extracts of germinated O. gratissimum and O. basilicum seeds exhibited more phytoconstituents content with significantly higher phenols (21.03 ± 0.01 mg gallic acid equivalent (GAE)/g and 21.46 ± 0.01 mg GAE/g respectively) and flavonoids (11.92 ± 0.03 mg quercetin equivalent (QE)/g and 14.45 ± 0.04 mg QE/g respectively) than other extracts did. Thus, they exhibited superior antioxidant potential with substantially lower half-maximal inhibitory concentration (IC50) values for scavenging 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) cation radical (0.013 ± 0.00 mg mL-1 and 0.007 ± 0.00 mg mL-1 respectively) and superoxide anion radical (4.33 ± 0.01 mg mL-1 and 4.14 ± 0.00 mg mL-1 respectively) and for inhibiting lipid oxidation (2.57 ± 0.00 mg mL-1 and 2.33 ± 0.00 mg mL-1 respectively) compared with other extracts. Further, they exhibited better antidiabetic potential with substantially lower IC50 values for inhibiting α-amylase activity (0.93 ± 0.01 mg mL-1 and 1.01 ± 0.01 mg mL-1 respectively) and α-glucosidase activity (0.60 ± 0.01 mg mL-1 and 0.51 ± 0.01 mg mL-1 respectively). Also, they showed superior antimicrobial potential with higher inhibition zones for Bacillus subtilis (13.98 ± 0.18 mm, 17.02 ± 0.18 mm respectively), Vibrio parahaemolyticus (19.00 ± 0.20 mm, 22.58 ± 0.45 mm respectively), Salmonella enterica (24.98 ± 0.18 mm, 22.17 ± 0.15 mm respectively), and Escherichia coli (23.50 ± 0.50 mm, 27.00 ± 0.20 mm respectively) and better inhibition of Aspergillus flavus growth (93.28% and 81.77% respectively) compared with other extracts.

CONCLUSION

Both the O. gratissimum and O. basilicum seed extracts can be utilized efficiently as therapeutic agents to manage inflammation-driven diseases and diabetes, or as natural preservatives in foods and in edible films or coatings. © 2025 Society of Chemical Industry.

Quality-controlled LC-ESI-MS food metabolomics of fenugreek (Trigonella foenum-graecum) sprouts: Insights into changes in primary and specialized metabolites

Fenugreek (Trigonella foenum-graecum L.) is an important food and spice with bioactive compounds against diabetes. In this study, fenugreek seeds germinating in darkness for 72 h were studied using quantification of trigonelline and 4-hydroxyisoleucine and an LC-ESI-MS/MS-based metabolomic approach capable of accurately estimating 237 features from various primary and specialized compound classes. During germination, the concentrations of trigonelline and 4-hydroxyisoleucine rose by 33.5% and 33.3%, respectively. At the same time, untargeted metabolomics revealed 9 putative flavonoids increasing 1.19- to 2.77-fold compared to the dormant seeds. A set of 19 steroid saponins rose by 1.08- to 31.86-fold. Primary metabolites however showed much more variability: abundance changes in amino acid derivatives, peptides and saccharides fell in the 0.09- to 22.25-fold, 0.93- to 478.79-fold and 0.36- to 941.58-fold ranges, respectively. To increase biosynthesis of specialized metabolites during germination, sprouts were exposed to 1-100 mM methyl jasmonate (MeJA) and methyl salicylate (MeSA). The hormone treatments affected normal metabolism: 67.1-83.1 % and 64.1-83.5 % of compounds showed a reduction compared to the controls in 100 mM MeJA and MeSA treatments at different sampling time points. Contrary to expectations, the abundance of flavonoids decreased, compared to the control sprouts (0.75- and 0.68-fold change medians, respectively). The same was observed for most, but not all steroid saponins. The quality-controlled untargeted metabolomics approach proved to yield excellent insight into the metabolic changes during germination of fenugreek. The results suggest that although fenugreek germination causes major shifts in plant metabolism, there are no major qualitative changes in bioactive specialized metabolites during the first three days. This stability likely translates into good bioactivity that is similar to that of the seeds. Because the large changes in the primary metabolites likely alter the nutritive value of the seed, further studies are warranted.

Egyptian chia seeds (Salvia hispanica L.) during germination: Upgrading of phenolic profile, antioxidant, antibacterial properties and relevant enzymes activities

Little studies on chia sprouts were not deeply address the polyphenols profiles and their functional properties during long period of germination. This study aims to evaluate the impact of germination process on the phenolic profile, antioxidant and antibacterial properties and relevant enzymes activities of Egyptian chia seeds. The total phenolic and flavonoid contents of chia sprouts increased several times during ten days of germination and maximized on 7-day sprouts (6.4 and 11.5 folds, respectively). In HPLC analysis, seventeen phenolic compounds were detected on 7-day sprouts compared to fifteen in dry seeds, where two new phenolic compounds (p-coumaric acid and kaempferol) were detected. The concentrations of all the identified phenolic compounds increased several folds (1.8-27) on 7-day sprouts. The total antioxidant activity increased 10, 17, and 29 folds on 7-day sprouts using DPPH, ABTS and PMC antioxidant methods, respectively compared to the dry seeds. Both antioxidant and carbohydrate-cleaving enzymes increased in chia sprouts and correlated with their phenolic content and antioxidant activity. The phenolic content of 7-day sprouts showed a potent antibacterial activity against some human enteric pathogenic bacteria including Escherichia coli O157-H7, Salmonella typhi, Pseudomonas aeruginosa and Staphylococcus aureus with lower MIC values compared to the raw seeds.

Biogenic nanosized gold particles: Physico-chemical characterization and its anticancer response against breast cancer

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Biogenic synthesized gold nanoparticles (AuNPs) falls in the range of 4−10 nm of spherical in shape.

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AuNPs exhibited anticancer potential against the various studied breast cancer cell lines.

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Flow cytometry analysis revealed that increasing dosage of AuNPs can induce apoptosis in cancer cells but PBMC remains unaffected.

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Also, Biogenic synthesized gold nanoparticles inhibit colony formation units as the dose increases.

With the advancement of nanotechnology, the nano-sized particles make an imprint on our daily lives.The present investigation revealed that biomolecules present in seed exudates of Vigna radiata are responsible for the synthesis of AuNPs, confirmed by the routine characterization techniques. Anticancer efficacy showed by AuNPs might be due to the release of phytochemicals in the exudate which is being adsorbed on the surface of AuNPs referencing their anticancer efficacy against the tested breast cancer cell lines. Inhibition of clonogenicity and cell cycle arrest at G2/M phase then apoptosis of AuNPs was also observed, but found nontoxic to the human PBMC cells which further confirms its biocompatible property Among the various physicochemical study, present AuNPs shows unique information, they show photoluminescent property which may be used for bioimaging purposes. However, further molecular analysis needs to be explored to understand the underlying mechanism for therapeutic and biomedical application.

Tannic acid elicits selective antitumoral activity in vitro and inhibits cancer cell growth in a preclinical model of glioblastoma multiforme

Glioblastoma is a devastating tumor affecting the central nervous system with infiltrative capacity, high proliferation rate and chemoresistance. Therefore, it is urgent to find new therapeutic alternatives that improve this prognosis. Herein, we focused on tannic acid (TA) a polyphenol with antioxidant and antiproliferative activities. In this work, the antitumor and antioxidant effects of TA on rat (C6) glioblastoma cells and their cytotoxicity relative to primary astrocyte cultures were evaluated in vitro. Cells were exposed to TA of 6.25 to 75 μM for 24, 48 and/or 72 h. In addition, colony formation, migration and cell adhesion were analyzed and flow cytometry was used to analyze cell death and cell cycle. Next, the action of TA was evaluated in a preclinical glioblastoma model performed on Wistar rats. In this protocol, the animals were treated with a dose of 50 mg/kg/day TA for 15 days. Our results demonstrated that TA induced in vitro selective antiglioma activity, not demonstrating cytotoxicity in astrocyte culture. It induced cell death by apoptosis and cell cycle arrest, reducing formation and size of colonies, cell migration/adhesion and showing to be a potential antioxidant. Interestingly, the antiglioma effect was also observed in vivo, as TA decreased tumor volume by 55%, accompanied by an increase in the area of intratumoral necrosis and infiltration of lymphocytes without causing systemic damage. To the best of our knowledge, this is the first study to report TA activity in a GBM preclinical model. Thus, this natural compound is promising as a treatment for glioblastoma.