Search

The current study was undertaken to investigate the antibacterial (against molecular characterized E. coli isolated from poultry faeces) potential of biosynthesized zinc oxide nanoparticles (ZnO-NPs) from Passiflora subpeltata Ortega aqueous leaf extract. The biosynthesized nanoparticles were subjected to physico-chemical characterization to study shape, size and purity by UV–Vis spectroscopy, X-Ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and Transmission Electron Microscopy (TEM). The molecular identification of isolated E. coli from faeces samples was carried out by using 16–23s rRNA primers. The results of the physico-chemical characterization revealed that the biosynthesized nanoparticles were of 93.7% purity with an average size between 45 and 50 nm. The ZnO-NPs offered significant inhibition against the isolated Gram-negative E. coli with MIC at 62.5 µg mL−1 concentration. The antibacterial potential of ZnO NPs against E. coli has also been investigated by the cell viability test, and further the effects of ZnO NPs on bacterial morphological structures was analysed by SEM and TEM.

In the current study, a total of 70 fungi were isolated from the rhizosphere soil of chilli collected from six different districts of south Karnataka, India. All the rhizospheric fungi were evaluated for its antagonistic nature against Colletotrichum capsici&mdash, the causal agent of anthracnose disease&mdash, and eight isolates were found positive. The antagonistic fungi were further characterized for the production of plant growth-promoting traits wherein five isolates were recorded positive for all the traits tested and were also positive for root colonization. All five plant growth-promoting fungi (PGPF) were subjected to molecular characterization for identification up to the species level and the accession numbers were obtained from NCBI. The five isolates, namely NBP-08, NBP-45, NBP-61, NBP-66 and NBP-67, were further experimented with on susceptible seeds to evaluate its efficacy on seed and plant growth parameters along with induction of resistance against the anthracnose disease. The evaluated PGPF offered significant enhancement in seed and plant growth parameters with maximum improvement observed in seeds treated with NBP-61. Among the PGPF isolates, NBP-61 showed the maximum protection of 78.75%, while all the other isolates also showed significant protection against anthracnose disease compared to untreated plants. The higher accumulation of lignin and callose deposition along with enhanced defense enzyme activities in the PGPF-treated challenge-inoculated seedlings authenticated the protection offered by PGPF. The study evidenced the immense ability of PGPF in eliciting disease protection and enhancement of plant growth in chilli, which may act as a possible substitute for harmful chemicals.

The development of advanced glycation end-products (AGEs) inhibitors is considered to have therapeutic potential in diabetic complications inhibiting the loss of the biomolecular function. In the present study, zinc oxide nanoparticles (ZnO-NPs) were synthesized from aqueous leaf extract of Morus indica and were characterized by various techniques such as ultraviolet (UV)-Vis spectroscopy, Powder X-Ray Diffraction (PXRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Further, the inhibition of AGEs formation after exposure to ZnO-NPs was investigated by in-vitro, in-vivo, and molecular docking studies. Biochemical and histopathological changes after exposure to ZnO-NPs were also studied in streptozotocin-induced diabetic rats. ZnO-NPs showed an absorption peak at 359 nm with a purity of 92.62% and ~6&ndash, 12 nm in size, which is characteristic of nanoparticles. The images of SEM showed agglomeration of smaller ZnO-NPs and EDS authenticating that the synthesized nanoparticles were without impurities. The biosynthesized ZnO-NPs showed significant inhibition in the formation of AGEs. The particles were effective against methylglyoxal (MGO) mediated glycation of bovine serum albumin (BSA) by inhibiting the formation of AGEs, which was dose-dependent. Further, the presence of MGO resulted in complete damage of biconcave red blood corpuscles (RBCs) to an irregular shape, whereas the morphological changes were prevented when they were treated with ZnO-NPs leading to the prevention of complications caused due to glycation. The administration of ZnO-NPs (100 mg Kg&minus, 1) in streptozotocin(STZ)-induced diabetic rats reversed hyperglycemia and significantly improved hepatic enzymes level and renal functionality, also the histopathological studies revealed restoration of kidney and liver damage nearer to normal conditions. Molecular docking of BSA with ZnO-NPs confirms that masking of lysine and arginine residues is one of the possible mechanisms responsible for the potent antiglycation activity of ZnO-NPs. The findings strongly suggest scope for exploring the therapeutic potential of diabetes-related complications.

Objective: An investigation on Aldose Reductase Enzyme (ALR) inhibitory activity of apigenin (API) isolated from Morus indica L. was evaluated by ex vivo and molecular docking studies. Materials and Methods: The inhibitory efficacy of API from M. indica was evaluated against ALR in lens tissue of mice by ex vivo and their binding mechanism through molecular docking was carried out by AutoDock. Results: The API (10-50 µg mL-1) concentration exhibited significant inhibition (p ≤ 0.05) of ALR enzyme in a dose dependent manner with IC50 value of 39.23 µg mL-1. The positive control aminoguanidine (AG) at 10 mM inhibited 42.96% of ALR. The molecular docking studies revealed that API showed better binding energy (-9.15 kJ mol-1) when compared to AG (-3.78 kJ mol1 ). Molecular interaction analysis showed that API interrupts the proton donation mechanism which is necessary for the catalytic activity of ALR by forming H-bond with Trp20 (proton donor). Conclusion: The ALR inhibition potential offered by API was further confirmed through molecular docking studies. The present findings support the pharmacological application of API for the treatment of diabetes cataract. Key words: Mulberry, Antiglycation, Retinopathy, Eye lens.

The present study focuses on the use of salicylic acid as a plant growth hormone for the induction of callus in Sauropus androgynus and Artemisia annua plants. Higher induction of callus of 72% in S. androgynus (NAA+BAP+SA at +2.5+2.5 mg/ l concentration) and 64% in A. annua (NAA+Kn+SA at 1.0+2.5+2.5 mg/ l concentration) were observed when compared to 52% and 51%, respectively in individual supplementation of plant growth regulators. The phytochemical analysis also revealed the presence of maximum phytochemicals in callus extract compared to leaf extracts of S. androgynus and A. annua there by corroborating with the results of callus induction. The methanol extracts of both callus and leaf extracts of S. androgynus and A. annua exhibited antibacterial activity against all the test pathogens viz., S. aureus, B. subtilis, S. typhi and E. coli. A maximum inhibition zone of 20 mm was observed against S. typhi in methanol callus extract of S. androgynus followed by 18 mm inhibition zone against S. aureus with same extract. It was evident from the results both callus and leaf extracts of the selected plants possessed potential antibacterial activity against all the test pathogens with one or the other solvent extracts. The findings provide a new facelift for callus induction using salicylic acid in selected plants and also pave way for identification of novel compounds for drug development from S. androgynus and A. annua.

The development of advanced glycation end-products (AGEs) inhibitors is considered to have therapeutic potential in diabetic complications inhibiting the loss of the biomolecular function. In the present study, zinc oxide nanoparticles (ZnO-NPs) were synthesized from aqueous leaf extract of Morus indica and were characterized by various techniques such as ultraviolet (UV)-Vis spectroscopy, Powder X-Ray Diffraction (PXRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Further, the inhibition of AGEs formation after exposure to ZnO-NPs was investigated by in-vitro, in-vivo, and molecular docking studies. Biochemical and histopathological changes after exposure to ZnO-NPs were also studied in streptozotocin-induced diabetic rats. ZnO-NPs showed an absorption peak at 359 nm with a purity of 92.62% and ~6–12 nm in size, which is characteristic of nanoparticles. The images of SEM showed agglomeration of smaller ZnO-NPs and EDS authenticating that the synthesized nanoparticles were without impurities. The biosynthesized ZnO-NPs showed significant inhibition in the formation of AGEs. The particles were effective against methylglyoxal (MGO) mediated glycation of bovine serum albumin (BSA) by inhibiting the formation of AGEs, which was dose-dependent. Further, the presence of MGO resulted in complete damage of biconcave red blood corpuscles (RBCs) to an irregular shape, whereas the morphological changes were prevented when they were treated with ZnO-NPs leading to the prevention of complications caused due to glycation. The administration of ZnO-NPs (100 mg Kg−1) in streptozotocin(STZ)-induced diabetic rats reversed hyperglycemia and significantly improved hepatic enzymes level and renal functionality, also the histopathological studies revealed restoration of kidney and liver damage nearer to normal conditions. Molecular docking of BSA with ZnO-NPs confirms that masking of lysine and arginine residues is one of the possible mechanisms responsible for the potent antiglycation activity of ZnO-NPs. The findings strongly suggest scope for exploring the therapeutic potential of diabetes-related complications.

Nanoparticles (NPs) prepared through safer, eco-friendly and natural-based products can be used various applications including antimicrobial and biomedical applications. Quorum sensing (QS) is a complex system for intercellular communication that regulates the expression of many virulence determinants, in the opportunistic Pseudomonas aeruginosa. Thus, the disruption of QS-mediated communication system could be an alternative strategy to combat infection caused by drug resistant P. aeruginosa. In this study, zinc oxide nanoparticles (ZnO NPs) were synthesized by using seed extract of Butea monosperma and further characterized by XRD, SEM and TEM. The biosynthesized ZnO NPs were then subjected to the investigation of their antibacterial, antibiofilm activities as well as the anti-quorum sensing potentialities for biomedical applications. The minimum inhibitory concentration (MIC) value against P. aeruginosa was found 1600 µg/ml, and it was found that ZnO NPs effectively reduced virulence factors Viz. swarming and swimming of P. aeruginosa by 62.8 and 45%, respectively. Exopolysaccharides production was also affected by ZnO NPs which indicate the disruption of biofilm formation. Further, the in silico docking analysis displayed that ZnO NPs efficiently interacted within QS (Las/Rhl) mechanism of P. aeruginosa by binding to the catalytic cleft of LasI synthase (Gly-116-ZnO = 2.8 A), RhlI synthase (Gly-180-ZnO = 3.7 A) and transcription receptor protein LasR receptor (Asn-141-ZnO = 2.9 A), RhlR receptor (Tyr-72-ZnO = 2.6 A). Thus, it was concluded that the effective interaction of ZnO NPs with Las and Rhl system led to the inactivation of autoinducers such as N-acyl homoserine lactones (AHL) molecules which finally led to the inactivation of QS and down regulation of virulence determinants. Consequently, the present in vitro and in silico results obtained suggest that the synthesized ZnO NPs can be efficiently used as potent antimicrobial agents to prevent the colonization, biofilm formation as well as anti-QS-mediated determinants caused by pathogenic drug resistant bacteria.

Boerhaavia diffusa L. is widely used for its ethno-medicinal properties. The present study assessed the antibacterial activity of endophytic fungi harbored in this plant. The endophytic fungi isolated belonged to various genera like Aspergillus, Cladosporium, Colletotrichum, Curvularia, Fusarium, Pestalotiopsis and Zygorhynchus and the overall colonization frequency of endophytic fungi was found to be 24%. Among the isolated fungi Aspergillus fumigatus, Cladosporium sphaerospermum, Fusarium sp. and Zygorhynchus sp. showed antibacterial activity in preliminary screening against one or all the test bacteria. Further, after fermentation, the ethyl acetate extracts of the selected endophytic fungi displayed variable antibacterial activity with maximum 54.75 mm and a minimum 27.50 mm zone of inhibition against test bacteria in disc diffusion assay. The lowest minimum inhibitory concentration (MIC) was 0.156 mg ml-1 in the broth dilution assay against a B. subtilis, S. typhi and Staph. aureus, while it was 0.312 mg ml-1 against E. coli which was offered by the ethyl acetate extracts of A. fumigatus.

A total of twenty two rhizospheric fungi were isolated from different healthy crop plants of Hassan, Karnataka, India and tested for its efficacy to solubilize phosphates in PKV medium. Among the isolates, Penicillium sp. RFUOM 14 solubilized phosphates by producing clear halo zone around the colony. Further, Penicillium sp. RFUOM 14 inducers were treated for different crop plants and observed that the treatments enhanced seed germination and seedling vigor. Among the treatments, conidial suspension treated for 6 h showed maximum of 86%, 80% and 83% of seed germination and seedling vigor 985.25, 523 and 673.5 in pearl millet, brinjal and tomato, respectively.