In Vitro Antibacterial, Antifungal, Antibiofilm, Antioxidant, and Anticancer Properties of Isosteviol Isolated from Endangered Medicinal Plant Pittosporum tetraspermum.

This study aimed to investigate the in vitro antibacterial, antifungal, antibiofilm, antioxidant, and anticancer properties of isosteviol isolated from endangered medicinal plant Pittosporum tetraspermum. Pure compound was obtained and characterized by column chromatography followed by (1)H NMR, (13)C NMR, IR, and mass spectral analysis. The antimicrobial activities of the compound were assessed by the broth microdilution method and the antioxidant properties were determined using reducing ability assay, DPPH scavenging assay, hydroxyl radical scavenging activity, and superoxide radical scavenging assay. Anticancer study was evaluated by following MTT assay. Column purification and spectrocopical analysis lead to identifying isosteviol from the crude ethyl acetate extract. The compound exhibited significant activity against bacteria such as Staphylococcus epidermidis (125 µg/mL), Staphylococcus aureus (125 µg/mL), and Klebsiella pneumoniae (62.5 µg/mL). The MIC of the compound against Candida albicans, Aspergillus niger, and Trichophyton mentagrophytes was 62.5, 125, and 500 µg/mL, respectively. The compound showed comparatively better antibiofilm activity against E. coli, S. typhi, and P. aeruginosa. Furthermore, it exhibited good antioxidant properties. Anticancer properties of the compound against Vero and MCF7 cell lines were its advantage. Novel isosteviol would be useful to reduce the infectious diseases caused by pathogenic microorganisms or slow the progress of various oxidative stress-related diseases.

In-vitro antibacterial, antifungal, antioxidant and functional properties of Bacillus amyloliquefaciens.

BACKGROUND: Food born pathogenic bacteria and filamentous fungi are able to grow on most foods, including natural foods, processed foods, and fermented foods and create considerable economic loss. The aim of this study was to determine the antibacterial, antifungal, antioxidant and functional properties of Bacillus amyloliquefaciens recovered from silage. METHODS: Minimum Inhibitory Concentration (MIC) of the compounds was assessed by using broth micro dilution method. The 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging and hydroxyl radical-scavenging abilities were measured to evaluate antioxidant activity of the strain. RESULTS: Primary antimicrobial compound production screening revealed that B. amyloliquefaciens exhibited significant activity against all the tested bacteria and fungi compared to other strains. The 16S rRNA and gyrase A gene sequence analysis determined using molecular biological tools confirmed that the strain was 99% similarity towards B. amyloliquefaciens. The Minimum Inhibitory Concentration (MIC) of ethyl acetate extract against Bacillus subtilis, Enterococcus cloacae and Staphylococcus aureus were 25.0 µg ml-1, and S, epidermidis were 12.5 µg ml-1, respectively. Filamentous fungi Aspergillus clavatus, A. fumigates, A. niger and Gibberella moniliformis showed 25 µg ml-1. VJ-1 was able to survive the gastrointestinal conditions simulating the stomach and duodenum passage with the highest percentage of hydrophobicity. In addition, its resistance to hydrogen peroxide and highest hydroxyl radical and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities, with inhibition rates of 56.84% and 67.12% respectively, were its advantage. An antimicrobial susceptibility pattern was an intrinsic feature of this strain, and thus, consumption does not represent a health risk to humans. CONCLUSION: Bacillus amyloliquefaciens might be a promising candidate for new pharmaceutical agents and probiotics.

In-vitro antimicrobial, antibiofilm, cytotoxic, antifeedant and larvicidal properties of novel quinone isolated from Aegle marmelos (Linn.) Correa.

BACKGROUND: Plant metabolites have wide applications and have the potential to cure different diseases caused by microorganisms. The aim of the study was to evaluate the antimicrobial, antibiofilm, cytotoxic, antifeedant and larvicidal properties of novel quinine isolated from Aegle marmelos (Linn.) Correa. METHODS: A compound was obtained by eluting the crude extract, using varying concentrations of the solvents by the chromatographic purification. Broth micro dilution method was used to assess the antimicrobial activity and anticancer study was evaluated using MTT assay. Larvicidal activity was studied using leaf disc no-choice method. RESULTS: Based on the IR, 13C NMR and 1H NMR spectral data, the compounds were identified as quinone related antibiotic. It exhibited significant activity against Gram positive and Gram negative bacteria. The lowest Minimum Inhibitory Concentration (MIC) of the compound against Bacillus subtilis and Staphylococcus aureus was 100 and 75 µg mL(-1) respectively. Against Escherichia coli and Pseudomonas aeruginosa it exhibited MIC value of 25 µg mL(-1). The MIC of the compound against Aspergillus niger, A. clavatus, Penicillium roqueforti was 20 µg mL(-1) and that against Fusarium oxysporum (20 µg mL(-1)), A. oryzae (40 µg mL(-1)), and Candida albicans (60 µg mL(-1)), respectively. It showed effective antibiofilm activity against E. coli, S. typhii and P. aeroginosa at 8 µg mL(-1) and did not exhibit considerable cytotoxic activity against Vero and HEP2 cell lines. Additionally, the compound documented significant antifeedant and larvicidal activities against Helicoverpa armigera and Spodoptera litura at 125, 250, 500 and 1000 ppm concentrations. CONCLUSION: The results concluded that the compound can be evaluated further in industrial applications and also an agent to prepare botanical new pesticide formulations.