Biogas Production Potential of Food Waste

At present our country is facing various problems, among that energy crisis has become more serious in next coming years. Both energy crisis and pollution problems could be controlled by adopting an alternative method of biogas production form waste products. Food waste is the best alternative for biogas production in a community level biogas plant. Hence in the present study, an attempt has been made to study the rate of biogas production in a lab scale biogas digester model for the efficient conversion of the food waste (starch –rich materials) generated from PRIST University Campus. The biogas production depends on the maximum biogas yield, the concentration of volatile solids of the input, the density of the effluent, the density of the biogas and the reaction rate constant, which are all substrate - or process - specific. The experiments were carried out for 40 days and the rate of gas production was measured by water displacement method. The pH value of the cow dung and food waste was initially measured and adjusted to nearer to neutral and gradually increased to acidic and again it got stabilised to the neutral pH which favoured the production of biogas. The percentage of total solids was 69.86, 93.56 and 25.67 for cow dung, food waste and digested slurry respectively. The percentage of volatile solids was 52.5, 86.3 and 18.9 for cow dung, food waste and digested slurry respectively. The percentage of volatile fatty acid was 285, 356 and 365 for cow dung, food waste and digested slurry respectively. Observations on daily basis were made on the constituent of biogas, pH, volume and rate of biogas production. The rate of biogas production continuously increased as days progressed and there was maximum yield in biogas after 20 days. Thus continuous feeding helps in daily biogas production and can be used at a small as well as larger scale to manage the organic waste and energy production for various applications

High Throughput DNA-DNA Microarray Chip Strategy for Detection and Identification of Enteropathogenic bacteria

The usability of the DNA microarray system for the specific detection of bacteria based on their unique genes was systematically evaluated with a model system composed of two pathogenic strains and two species specific oligonucleotide probes. Escherichia coli O157: H7 and Salmonella enterica are pathogens which have very low infectious doses (as low as 10 cells), and these bacteria often exist within complex biological matrixes. Detection and identification of these pathogenic bacteria in less number was achieved. Bacteria was subjected to whole genome multiplication and labeled while amplifying the specific partial target gene sequence itself. Microarry chips were printed by free hand method and used for hybridization. This culture independent detection method could be fastening the diagnosis term for the swift food material quality control and therapeutic purpose too

Habitat diversity of hermit crab Clibanarius longitarsus (de haan) in vellar estuary, Southeast coast of India

The habitat diversity of hermit crab Clibanarius longitarsus was studied in 5 stations of Vellar estuary.  This hermit crab was found to occupy the shells of as many as 44 species of gastropods. The abundance of this hermit crab (144/m2- 41/m2) so also the number species of gastropod shells it occupied decreased from the mouth to the upper reaches of estuary (39-11 species).  The Shannon diversity (H’log2) was in the range of 4.08-2.64 in stations 1-5. The Margalef species richness showed clear differences between the stations and it varied from 7.52 in station 1 to 2.69 in station 5. The evenness was more in station 1 (0.77) and decreased to 0.65 in station 2 and thereafter it increased in stations 3 and 4 to reach 0.76 in station 5. The taxonomic diversity index decreased from station 1 (75.48) to station 4 (58.59) and increased in station 5 (62.2). The total phylogenetic diversity index which was more in station 1 (1840) decreased through stations 2-5 to reach 660 in station 5. The variation in taxonomic distinctness index increased from station 1 (362.67) to station 3 (468.78).  The similarity in species composition of gastropod shells among the stations was in the range of 50.55%-81.73%. In cluster analysis the grouping was quite clear with stations in the lower reaches (stations 1 and 2) forming a group and stations in the middle of the estuary (stations 3 and 4) forming a group to which the station in the upper reaches (station 5) got linked. The cluster analysis and MDS clearly showed the variation in species composition between the stations. The average dissimilarity in species composition between stations 1 and 5 was 63.61%. Gastropod species which contributed to greater percentage of dissimilarity were Cerithidea fluviatilis, Umbonium vestiarium, Pila globosa, Babylonia spirata and Turritella acutangula. The abundance shown as bubble plot clearly showed the decreasing abundance of Cerithidea cingulata, Babylonia spirata and Turritella acutancula from the mouth to the upstream stations. The taxonomic relatedness tests carried out (95% funnel and 95% ellipse) also clearly showed the differences in the habitat diversity of the hermit crab in different stations of Vellar estuary

Effect of Taurine and Glutathione on Mercury Toxicity in Liver Tissue of Rats

The present investigation examined the ability of taurine and glutathione as an antioxidant to protect against mercury induced oxidative stress and hepatotoxicity. Mercury hepatotoxicity was induced by oral administration of mercury at a dose of 2 mg/kg body weight daily for 30 days. Hepatotoxicity was assessed by reduced serum total protein level and increased serum levels alanine aminotransferase (ALT), and aspartate aminotransaminase (AST) and alkaline phosphatase (ALP) and total protein. Mercury treatment increased lipid peroxidation (LPO) measured as thiobarbituric acid reactive substances (TBARS) concentration and decreased reduced glutathione (GSH) content in the rat liver.  Again taurine and glutathione is administrated for 15 days. During this period, taurine improved liver functions, as indicated by decline of serum transaminases and ALP levels and elevation of serum total protein. Moreover, taurine significantly reduced AST, ALT, ALP and hepatic TBARS and increased GSH content and total protein in the hepatic tissue. These results indicate that taurine has a protective action against mercury induced hepatic damage in rats than glutathione

BIO-PROSPECTING OF CLEISTANTHUS COLLINUS AND ITS ANTIBACTERIAL ACTIVITY

Objective: This present study was planned to resolve the phytochemical profile of the plant leaf extracts prepared by two different (hot and cold) extraction methods and to determine the bactericidal efficiency of Cleistanthus collinus. Methods: Preliminary phytochemical analysis of C. collinus leaf crude extracts (methanol, ethanol, ethyl acetate and aqueous) were performed according to the Odebiyi method. The bactericidal efficiency of C. collinus leaf crude extracts were tested by standard microbiological methods against Escherichia coli, Salmonella typhi, Klebsiella pneumoniae, Pseudomonas aeruginosa (Gram-negative) and Staphylococcus aureus, Listeria monocytogenes (Gram-positive). Results: The presence of secondary metabolites like alkaloids, flavonoids, steroids, terpenoids, tannins, phlobatannins, glycosides and saponins were observed in preliminary phytochemical analysis of C. collinus leaf crude extracts. Analysis of bactericidal efficiency for the various solvent based extracts revealed that methanol extract of C. collinus was found to be intensive antibacterial activity [> 18 mm inhibition zone; MIC (0.27 - 0.42 mg/ml); MBC (0.35 – 0.50 mg/ml)] which is followed by ethanol extract and other extracts.   Conclusion: From this study, it is obvious that the C. collinus leaf crude extract could be exploited for the preparation of new and efficient green medicine to treat various infectious diseases for both human being and veterinary animals. Keywords: Cleistanthus collinus, Phytochemistry, Bioprospecting, Antibacterial activity, MIC, MBC