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A B S T R A C TThe biosynthesis of silver nanoparticles by the reduction of aqueous silver metal ions during revelation to both fresh, dry tuber extract and in vitro antioxidant, antibacterial activity of sweet potato were studied. Tuber extract of sweet potato was prepared for the synthesis of silver nanoparticles under different reaction time. The prepared materials were characterized by UV-visible spectroscopy, X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR). During incubation period, the intensity of colour increased and its characteristic absorption was recorded at 428 and 439 nm. X-ray diffraction showed that the average particles size 4.77 and 5.6 nm. The FT-IR spectra of the tuber extract and synthesized silver nanoparticles revealed the reducing and capping actions of biomolecules such as amine, peptide, amide, lactone, polyphenol groups in protein linkages and it was found to be involved in the stabilization and biosynthesis of AgNPs. Scanning Electron Microscopy (SEM) showed silver nanoparticles was pure and the sizes were ranging from 1-10 µm. Green synthesized silver nanoparticles exhibited strong antioxidant and effective antibacterial activity against human pathogenic bacteria. Thus, green synthesis seems to be cost effective and alternate to conventional methods of silver nanoparticles synthesis. No synthetic reagent were used in this investigation and thus it is an environmentally safe method with potential for biomedical and agriculture application.

VCTO encompassing pull–pull and push–pull categories has been appraised for fine tuning of band gaps and optoelectronic application through DFT/TDDFT calculations.

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Objectives: The aim of this research work was to carry out the phytochemical screening and to evaluate the antibacterial and antifungal activity of the whole plant extract (shoot, flower, and tuber) of the flame lily (Gloriosa superba). Materials and Methods: In the current work, phytochemicals were extracted from different parts of the plant using different solvents dimethyl sulfoxide, ethyl acetate, and ethanol (ETOH). These phytochemicals contained alkaloids, flavonoids, terpenoids, tannins, saponins, aromatic acids, phenolic compounds, xanthoproteins, triterpenoids, amino acids, philobatinins, carbohydrate, reducing sugar, and proteins and they were separated using standard methods. Furthermore, antimicrobial activities of methanolic separation were determined using various species of bacteria and fungi. Agar well diffusion method was used for the antimicrobial activity and the zone of the inhibition was analyzed. Results: The evaluation of preliminary phytochemical screening of extracts indicated the presence of carbohydrates, reducing sugars, proteins, amino acids, steroids, flavonoids, terpenoids, saponins, alkaloids, tannins, and phlobatannins. Tuber extracts highlighted effective antibacterial and antifungal activities compared with shoot and flower extracts against all the tested bacteria and fungi. ETOH extract of the tuber observed highest antibacterial activity against Staphylococcus aureus (19 mm), followed by Escherichia coli (18 mm), Micrococcus luteus (17 mm), Pseudomonas aeruginosa (17 mm), and Salmonella abony (16 mm) when compared to shoot and flower extracts. G. superba tuber extracts highlighted effective antifungal activities compared with shoot and flower extracts against all the tested fungi. ETOH extract of the tuber observed highest antifungal activity against Rhizopus oryzae (20.17 mm), followed by Mucor Sp. (19.87 mm), Aspergillus niger (18.02), Candida krusei (17.98 mm), and Candida albicans (16.88 mm) as compared to shoot and flower extracts. Conclusion: Results of the current studies flame lily ETOH extracts showed that the plant has significant antimicrobial activities. The strong antibacterial and antifungal activities of flame lily are due to the presence of tannins and flavonoids present in.