Isolation and Characterization of Bacteria from the Gut of Bombyx mori that Degrade Cellulose, Xylan, Pectin and Starch and Their Impact on Digestion

Bombyx mori L. (Lepidoptera: Bombycidae) have been domesticated and widely used for silk production. It feeds on mulberry leaves. Mulberry leaves are mainly composed of pectin, xylan, cellulose and starch. Some of the digestive enzymes that degrade these carbohydrates might be produced by gut bacteria. Eleven isolates were obtained from the digestive tract of B. mori, including the Gram positive Bacillus circulans and Gram negative Proteus vulgaris, Klebsiella pneumoniae, Escherichia coli, Citrobacter freundii, Serratia liquefaciens, Enterobacter sp., Pseudomonas fluorescens, P. aeruginosa, Aeromonas sp., and Erwinia sp.. Three of these isolates, P. vulgaris, K. pneumoniae, C. freundii, were cellulolytic and xylanolytic, P. fluorescens and Erwinia sp., were pectinolytic and K. pneumoniae degraded starch. Aeromonas sp. was able to utilize the CMcellulose and xylan. S. liquefaciens was able to utilize three polysaccharides including CMcellulose, xylan and pectin. B. circulans was able to utilize all four polysaccharides with different efficacy. The gut of B. mori has an alkaline pH and all of the isolated bacterial strains were found to grow and degrade polysaccharides at alkaline pH. The number of cellulolytic bacteria increases with each instar

IMPACT OF SPACE ON DEVELOPMENT, SIZE, OVIPOSITION PATTERN AND HATCHABILITY OF ACANTHASPIS PEDESTRIS STAL (HETEROPTERA : REDUVIIDAE)

The laboratory hatched first instar nymphs of A. pedestris were reared in three different sized containers, such as, 52, 104 and 208 ml and were given uniform quality and quantity of prey. The total stadial period was shortest among individuals reared in 104 m) containers and almost same among individuals reared in 52 and 208 ml container. Adult longevity was the longest among individuals reared in 208 ml container and shorter among individuals reared in 52 and 104 ml containers. Reduction in s ace caused female biased sex ratio. Space had a direct impact on both egg and adult morphometry. As the volume of the container increased, the length and width of various regions also increased Individuals reared in 52 ml containers were reproductively efficient than the individuals reared in 104 and 208 ml containers in having more index of oviposition days, more number of batches of eggs, more number of eggs, higher average number of eggs per batch, maximum number of eggs per batch and total number of nymphs hatched etc. Reduction in space increased the reproductive potential and decreased the sizc of A. pedestris

BIOLOGY AND BEHAVIOUR OF SPHEDANOLESTES SIGNATUS DISTANT (INSECTA : HETEROPTERA : REDUVIIDAE) A POTENTIAL PREDATOR OF HELOPELTIS ANTONII SIGNORET

S. signatus Distant is found to inhabit among bushes in the scrub jungles and the agroecosystems of southern Tamil Nadu. It is entomophagous and predating on a variety of arthropods including insect pests in a sequential pattern : arousal-orientation-fixation-antennal extension-prey contact-rostral insertion-paralysing the victim-transportation-rostral thrusting and withdra­wal-lifting of the prey-suction and evacuation-dropping the empty case-post predatory cleaning. The mating behaviour is also exhibited in a sequential pattern; arousal-approach-nuptial clasp-riding over-embracing-genitalia extension and connect- ion-termination of copulation and post copulatory acts. It lays ochraceous eggs in 9 d after emergence singly and cementing basally. The eggs hatch in between 10 to 15 d and the pale ochraceous nymphs turn into deep ochrace­ous within 1 h. The total stadial period from I instar to adult ranges from 49 to 58 d. The males live longer (27.5 d) when compared to females (21 d). The sex ratio is unbiased

High-Level Expression of Functionally Active Dengue-2 Non-Structural Antigen 1 Production in Escherichia coli

Detection of nonstructural protein (NS1) is an important diagnostic marker during acute phase of dengue infection. Not only for diagnostic purpose, the protein had important role in vaccine design as well, as a candidate for studying virus assembly and maturation. Various researchers employed different expression systems and strategies for recombinant NS1 protein production. Attempts to express NS1 protein in prokaryotic and yeast expression system result in formation of insoluble protein which needs to undergo refolding to attain native structural and functional forms. Here, we report the production of soluble NS1 protein in E. coli by using appropriate vector and employing suitable culture conditions to maximize protein production. Proteins were purified using metal affinity chromatography. SDS-PAGE and western blot analysis reveal the native structure of NS1 protein. Solid phase ELISA using the recombinantly expressed antigen with positive and negative dengue samples showed that the expressed protein retains its antigenic and immunological properties. To our knowledge, this is the first report on the successful production of functionally active recombinant dengue-2 NS1 protein production without undergoing any in vitro posttranslational modification process

Biodiesel production from marine cyanobacteria cultured in plate and tubular photobioreactors

262-268Carbon (neutral) based renewable liquid biofuels are alternative to petroleum derived transport fuels that contribute to global warming and are of a limited availability. Microalgae based biofuels are considered as promising source of energy. <i style="mso-bidi-font-style: normal">Lyngbya sp. and Synechococcus sp. were studied for the possibility of biodiesel production in different media such as ASNIII, sea water enrichment medium and BG11. The sea water enrichment medium was found superior in enhancing the growth rate of these microalgae. Nitrogen depletion has less effect in total chlorophyll <i style="mso-bidi-font-style: normal">a content, at the same time the lipid content was increased in both Lyngbya sp. and <i style="mso-bidi-font-style: normal">Synechococcus sp. by 1.4 and 1.2 % respectively. Increase in salinity from 0.5-1.0 M also showed an increase in the lipid content to 2.0 and 0.8 % in these strains; but a salinity of 1.5 M has a total inhibitory effect in the growth. The total biomass yield was comparatively higher in tubular LED photobioreactor than the fluorescent flat plated photobioreactor. Lipid extraction was obtained maximum at 60 ºC in 1:10 sample: solvent ratio. GC-MS analysis of biodiesel showed high content of polyunsaturated fatty acids (PUFA; 4.86 %) than saturated fatty acid (SFA; 4.10 %). Biodiesel production was found maximum in Synechococcus sp. than Lyngbya sp. The viscosity of the biodiesel was closely related to conventional diesel. The results strongly suggest that marine microalgae could be used as a renewable energy source for biodiesel production