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The green synthesis of metal and metal-oxide nanoparticles is a growing research area due to the ... more The green synthesis of metal and metal-oxide nanoparticles is a growing research area due to the potential applications in the growth of novel technologies. The present work reports low-cost, green synthesis of zinc oxide nanoparticles using Cissus quadrangularis stems extract. The biosynthesized nanoparticles were characterized by UV, FTIR, XRD and SEM. The synthesized ZnO nanoparticles were pure, predominantly spherical in shape with the size ranging from 23 to 64 nm. In the present study the biosynthesized ZnO nanoparticles have been used for various in vitro activities such as antihelmintic, antibacterial, antiarthritic and antioxidant activities. Zinc oxide nanoparticles demonstrated antioxidant activity by scavenging 36 % hydrogen peroxide at 100 µg/mL and revealed excellent antihelmintic effect by show casing the death of the worm at all the concentrations at different times. The antibacterial study was done by agar-well diffusion method and the maximum inhibition zones around the ZnO nanoparticles were observed in E. coli followed by S. aureus, Listeria sp, Salmonella sp and Klebsiella sp. The percentage stabilization of aqueous extract was found to be 93 % inhibition on bovine serum albumin method and 91 % inhibition on egg albumin denaturation method which confirms the antiarthritic activity. Therefore, the study reveals an eco-friendly, efficient and simple method for the green synthesis of multifunctional ZnO nanoparticles using green synthetic approach.

The aim of this study is to develop an easy and eco-friendly method for the synthesis of Ag-NPs u... more The aim of this study is to develop an easy and eco-friendly method for the synthesis of Ag-NPs using extracts from the medicinal plant, Millettia pinnata flower extract and investigate the effects of Ag-NPs on acetylcholinesterase (AChE), butyrylcholinesterase (BChE), antibacterial and cytotoxicity activity. UVeVis peak at 438 nm confirmed the Ag-NPs absorbance. The SEM analysis results confirmed the presence of spherical shaped Ag-NPs by a huge disparity in the particle size distribution with an average size of 49 ± 0.9 nm. TEM images revealed the formation of Ag-NPs with spherical shape and sizes in the range between 16 and 38 nm. The Ag-NPs showed an excellent inhibitory efficacy against AChE and BChE. The highest antibacterial activity was found against Escherichia coli (20.25 ± 0.91 mm). These nanoparticles showed the cytotoxic effects against brine shrimp (artemia saliana) nauplii with a LD 50 value of 33.92.

Leucas aspera commonly known as 'Thumbai' has a wide variety of medical applications. The aqueous... more Leucas aspera commonly known as 'Thumbai' has a wide variety of medical applications. The aqueous extract of Leucas aspera (leaf extract) was assessed for its various in vitro activities such as anti-inflammatory, anti-helminthic, anti-arthritic, anti-oxidant and anti-bacterial activity. The in vitro Anti-inflammatory activity was studied by human red blood cell (HRBC) membrane stabilization method by using various concentration of L. aspera. The results showed that the HRBC Membrane stabilization activity of the aqueous leaf extract of L. aspera at concentration of 100μg/ml showed 73.25% inhibition of denaturation in hypotonic solution while the standard Diclofenac 100μg/ml showed 79.25% inhibition of denaturation. The crude extracts of the leaves of Leucas aspera showed statistically significant anti-inflammatory activity in in vitro assay.The crude aqueous leaves extract of Leucas aspera also showed that significant anti-helmintic effect causing death of the worm at all the concentrations but the time of death was different in each case. Invitro anti-arthritic activity was carried out by bovine serum protein denaturation method and egg albumin denaturation method. The results suggested that the aqueous extract of L. aspera showed a very good anti-arthritic activity. Antioxidant and Antibacterial activity was also evaluated. The present study concluded that the plant can be formulated in broad spectrum antibiotics and also confirms the traditional uses in pathogenic disease.

Protease executes a large variety of functions and it has many biotechnological applications. It ... more Protease executes a large variety of functions and it has many biotechnological applications. It represents as one of the third largest group of industrial enzyme and finds its applications in detergents, leather industry, pharmaceutical industry etc. Among the different vegetable waste products, peel of Manihot esculenta (Tapioca/ cassava) was used as substrates for the production of protease by Bacillus sp. The aim of our study is to utilize the waste of Tapioca peel as input for protease production using Bacillus sp. The protease produced by Bacillus sp from M. esculenta showed a pH of 10 and temperature of about 30°C. Protease produced was tested for possible industrial applications. This enzyme shows high capacity in removing the blood stain, dehairing the animal skin, digestion of natural proteins and bioprocessing of used X-ray film. The wash performance analysis of blood stains on cotton fabrics showed that blood stains were completely removed within 15 minutes of incubation of fabrics along with enzyme. Complete hair removal of goat skin by the protease achieved within 12 hours of incubation at 30°C. This enzyme has the ability to dissolve the blood clot and coagulated egg within 20 minutes of incubation. Enymatic hydrolysis of gelatin from waste X-ray films was also investigated. At the end of the treatment, gelatin layer was completely removed leaving the polyester film clean. Gelatin hydrolysis was monitored by measuring increase in turbidity. Gelatin layer was removed completely within 10 minutes of addition of enzyme. The protease produced exhibits high antibacterial activity against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The present study was a humble attempt towards the production of protease and to check their efficiency in industrial applications. These properties indicate the possibilities of enzyme usage in various industries and it can be exploited commercially in future.

Marine environmental conditions are extremely different from terrestrial ones, because every clas... more Marine environmental conditions are extremely different from terrestrial ones, because every class of marine microbes produces a number of bioactive compounds with unique structural features. Of all the marine microbes, the actinomycetes have a special consideration since it produces a novel bioactive compounds. Hence, marine sediments, collected from the coastal areas of Rameshwaram and Dhanushkodi of Tamilnadu state, India, were screened and eighteen isolates were obtained on Starch-Casein agar media by soil dilution technique. However, only seven isolates showed significant antibacterial activity against Escherichia coli, Proteus mirabilis, Bacillus cereus, and Staphylococcous aureus. GC-MS results reveal that two compounds N-Isopropyluredo Acetic Acid and Benzene Propanamine, N-(1, 1-Dimethyl Ethyl)-Alpha Methyl-Gamma Phosphate were present in the isolates. Morphological, cultural, biochemical characterization and Gene sequencing indicated that the isolates belong to Streptomyces genus of Actinomycetes. The Phylogenetic study reveals the species name as Steptomyces globosus, and hence the strain is named as VITR004. Therefore, the isolation, characterization of the rare actinomycetes from the coastal areas of Rameshwaram and Dhanushkodi of Tamilnadu state, India will be useful for the discovery of the novel bioactive metabolites that are effective against wide range of pathogens.

In the present work, copper nanoparticles (Cu NPs) have been synthesized by simple and green tech... more In the present work, copper nanoparticles (Cu NPs) have been synthesized by simple and green technique by using Tridax procumbens leaf extract. The formation of Cu NPs is monitored by recording the UV-Vis absorption spectra which showed surface Plasmon resonance at 320 nm. The green synthesized Cu NPs were further characterized by FT-IR, SEM and XRD. FT-IR identified the presence of active and phenolic groups. The crystalline morphology and size of the nanoparticles were determined by SEM and X-ray diffraction studies. The average particle size of Cu nanoparticles was found to be in the range of 71 nm. These biologically synthesized Cu NPs were tested for antimicrobial activity against five pathogens. The Cu Nps were also used for the remediation of a Bismarck brown dye. Approximately, 89% degradation of Bismarck brown dye was observed within 72 hours using Cu NPs. The mechanism involved in the degradation of dye and its phytotoxicity study has been presented. The overall outcome of this study suggests that the green synthesis of Cu NPs hold promise as a potent antimicrobial and antioxidant agent. The particles obtained were also found to degrade Bismarck brown dye.

Bottle gourd (Lagenaria siceraria) belongs to the family Cucurbitaceae, which comprises about 118... more Bottle gourd (Lagenaria siceraria) belongs to the family Cucurbitaceae, which comprises about 118 genera and 825 species. It is an important vegetable crop of India, and its production is influenced by a number of factors viz., environmental, nutritional, cultural operation and use of plant growth regulators. Since, bottle gourd belongs to a medicinal family, it plays a major role in the treatment of several diseases related to the skin and heart. There are several organic chemical compounds including vitamin B complex, pectin, dietary soluble fibres, ascorbic acid, beta-carotene, amino acids and minerals which have been isolated from this species. Therefore, the bottle gourd is considered to have a great impact on therapeutic health benefits. Due to drastic industrialization and urbanization, most of the human beings are facing several ill effects which may lead to death at extreme cases. Hence, the major research area was said to be nanotechnology. Taking into consideration, we have combined nanotechnology field with waste source in the name of green synthesis and planned to cure several diseases, as most of the researchers focused their work on this and succeeded too. The present study is a complete review of L. siceraria that covers the ethnomedical uses, chemical constituents, and pharmacological profile. This study is mainly focused on the antibacterial, hepatoprotective, diuretic and anthelminthic activities.

The Biomedical and Health Care waste management is very different from other house waste or indus... more The Biomedical and Health Care waste management is very different from other house waste or industries waste management. Biomedical waste management is one of the biggest challenges of the present day times because it has a direct impact on the health of human beings. Since it is hazardous in nature its safe and proper disposal is extremely important. For proper disposal management of biomedical waste the Ministry of Environment and Forests has published the Bio-Medical Waste Rules, 1998. This review explains the hospital waste management and the environmental problem in India. This study also focused on the problems associated with Biomedical waste. In the past, medical waste was often mixed with municipal solid waste and disposed in nearby landfills. In recent years, many efforts have been made by environmental regulatory agencies to better manage the biomedical waste.

In this study, the agricultural waste was used to screen for an organism that is capable of produ... more In this study, the agricultural waste was used to screen for an organism that is capable of
producing enzymes for degrading xylan. Streptomyces sp. are the important source of enzyme
involved in lignocellulosic degradation. Streptomyces sp. was isolated from different soil samples.
Out of 10 different soil samples, 6 samples gave the best result in starch casein agar plates.
Screening was mainly carried out to detect the enzyme and a clear zone surrounding the growth
was seen if enzyme xylanase was present. Substrates being cheap and readily available, have
recently gained considerable interest because of their possible use in fermentation process.
Streptomyces sp., produces xylanase on various feed stuffs like sugarcane molasses, oat spelt xylan,
Tomato pomace, Rice bran, wheat bran and saw dust under submerged fermentation condition. The
attempts have been made to replace a xylan, costly substrate for xylanase to make xylanase
production cost effective. The xylanase activity in each production medium was confirmed by
measuring the amount of reducing sugars liberated from the medium by the DNS method using
crude extract. The application of the crude enzyme in deinking of newsprint was also studied.