Exploration of Phyllanthus acidus mediated silver nanoparticles and its activity against infectious bacterial pathogen.

In our present investigation, synthesis of nontoxic, eco friendly and cost effective silver nanoparticles, Phyllanthus acidus (P. acidus) was used as starting material. The influence of phyto-constituents present in aqueous extracts of Phyllanthus acidus was found to be effective in reduction of silver nitrate to free silver nanoparticles (PA-AgNPs). HPTLC finger print analysis reveals the presence of flavonoid, quercetin in aqueous extracts of Phyllanthus acidus. Surface plasmon racemonance exhibited λ max at 462 nm through UV-Vis spectroscopy. Zeta size revealed that the size of nanoparticles were with in the range of 65-250 nm with polydisperse index (PDI) of 0.451. The negative charge of zeta potential value (- 16.4) indicates repulsion among PA-AgNPs with their excellent stability. FESEM-EDAX, XRD and TEM analysis confirmed the presence of nano-crystalline PA-AgNPs with different morphological textures. Further, PA-AgNPs has shown potent antibacterial effect on E. coli cells. The greater antibacterial effect (viable and dead cells) of PA-AgNPs were confirmed by using acridine orange (AO) dye which can able to provide insight of healthy as well as damaged DNA. Live cells emit florescence green and dead cells (treated with PA-AgNPS at 20 and 40 µg/ml) appear as pale orange red colour. Post treatment, investigations of PA-AgNPs on E. coli cells under SEM was found to be effective against cell membrane damages which leads to cell death or cell growth arrest. Hence, from the above findings, we strongly recommend silver nanoparticles from Phyllanthus acidus can be used as a potential source for antimicrobial agent for chronic infections and also against other harmful microorganisms.

Production of Laccase by Cochliobolus sp. Isolated from Plastic Dumped Soils and Their Ability to Degrade Low Molecular Weight PVC.

One of the utmost man-made problems faced today has been the ever-increasing plastic waste filling the world. It accounts for an estimated 20-30% (by volume) of municipal solid waste in landfill sites worldwide. Research on plastic biodegradation has been steadily growing over the past four decades. Several fungi have been identified that produce enzymes capable of plastic degradation in various laboratory conditions. This paper presents a study that determined the ability of fungi to degrade low molecular weight polyvinyl chloride (PVC) by the enzyme laccase. We have isolated a fungal species, Cochliobolus sp., from plastic dumped soils and they were cultured on Czapek Dox Agar slants at 30°C. The effectiveness of this fungal species on the degradation of commercial low molecular weight polyvinyl chloride (PVC) was studied under laboratory conditions. Significant differences were observed from the FTIR, GC-MS, and SEM results in between control and Cochliobolus sp. treated PVC.

Promising upshot of silver nanoparticles primed from Gracilaria crassa against bacterial pathogens.

BACKGROUND: The study on newer antimicrobial agent from metal based nano materials has augmented in recent years for the management of multidrug resistance microorganisms. In our present investigation, we synthesized silver nanoparticles (AgNP's) from red algae, Gracilaria crassa as beginning material which effectively condensed the silver ions to silver nanoparticles with less price tag and no risk. METHODS: Silver nanoparticles were prepared by simple reaction of 1 mM AgNO3 with G. crassa extracts at room temperature. The fabricated AgNP's were subjected for characterization and screened against various microorganisms for antibacterial activity. RESULTS: UV-Vis spectroscopy (200-800 nm), XRD, FESEM and EDAX, were performed for AgNP's. UV-Vis spectroscopy demonstrated the absorption edge at 443 nm and EDAX pattern is purely due to the particle size and face centered cubic (fcc) symmetry of nanoparticles. Average size lays at 122.7 nm and zeta potential was found to be -34.9 mV. The antibacterial outcome of synthesized AgNP's (at the dose of 20 and 40 µg/ml) was evaluated against Escherichia coli, Proteus mirabilis, Bacillus subtilis and Pseudomonas aeruginosa. The mechanism of synthesized AgNP's bactericidal bustle is discussed in terms of interaction with the cell membrane of bacteria. The activity was found to be sky-scraping in a dose dependent manner. CONCLUSION: Thus, environmental friendly, cost effective, non hazardous stable nanoparticles were prepared by green synthesis using red algae, G. crassa. Synthesized G. crassa AgNP's were in acceptable size and shape. Further, it elicits better bactericidal activity against microorganism. This will assure the out put of superior antibacterial formulation for near future.

Production of bioactive compounds by actinomycetes and their antioxidant properties.

An actinomycete was isolated from mangrove soil collected from Nellore region of Andhra Pradesh, India, and screened for its ability to produce bioactive compounds. The cultural, morphological, and biochemical characters and 16S rRNA sequencing suggest that the isolated strain is Nocardiopsis alba. The bioactive compounds produced by this strain were purified by column chromatography. The in vitro antioxidant capacity of the isolated compounds (fractions) was estimated and fraction F2 showed very near values to the standard ascorbic acid. The potential fraction obtained by column chromatography was subjected to HPLC for further purification, then this purified fraction F2 was examined by FTIR, NMR, and mass spectroscopy to elucidate its chemical structure. By spectral data, the structure of the isolated compound was predicted as "(Z)-1-((1-hydroxypenta-2,4-dien-1-yl)oxy)anthracene-9,10-dione."

Development of a probe-based blotting technique for the detection of tobacco streak virus.

Digoxigenin (DIG)-labeled DNA probe was developed for a sensitive and rapid detection of the tobacco streak virus (TSV) isolates in India by dot-blot and tissue print hybridization techniques. DIG-labeled DNA probe complementary to the coat protein (CP) region of TSV sunflower isolate was designed and used to detect the TSV presence at field levels. Dot-blot hybridization was used to check a large number of TSV isolates with a single probe. In addition, a sensitivity of the technique was examined with the different sample extraction methods. Another technique, the tissue blot hybridization offered a simple, reliable procedure and did not require a sample processing. Thus, both non-radioactively labeled probe techniques could facilitate the sample screening during TSV outbreaks and offer an advantage in quarantine services.