Control of Culex quinquefasciatus (Diptera: Culicidae) by Bacillus sphaericus and B. thuringiensis subsp. israelensis, Produced on a New Potato Extract Culture Medium

The efficacy of Bacillus sphaericus and B. thuringiensis israelensis produced on a new potato-based culture medium as well as the conventional culture medium of Luria Bertani was compared against Culex quinquefasciatus in the field. After sporulation, the spores/crystals were harvested and used. The bacterial samples controlled the larvae and pupae for three weeks. Mortality due to the bacterial toxins produced from the new culture medium was very high and comparable to that produced using conventional medium. But the cost for cultivating these bacteria using potato extract was much lower as compared with that of the conventional medium.     

Isolation and characterization of bioactive compounds of Clematis gouriana Roxb. ex DC against snake venom phospholipase A2 (PLA2) computational and in vitro insights

Bioactive compounds were isolated from Clematis gouriana Roxb. ex DC. The compounds were separated, characterized, the structures elucidated and submitted to the PubChem Database. The PubChem Ids SID 249494134 and SID 249494135 were tested against phospholipases A₂ (PLA₂) of Naja naja (Indian cobra) venom for PLA₂ activity. Both the compounds showed promising inhibitory activity; computational data also substantiated the results. The two compounds underwent density functional theory calculation to observe the chemical stability and electrostatic potential profile. Molecular interactions between the compounds and PLA₂ were observed at the binding pocket of the PLA₂ protein. Further, this protein–ligand complexes were simulated for a timescale of 100 ns of molecular dynamics simulation. Experimental and computational results showed significant PLA₂ inhibition activity.     

Cholesterol 7α-hydroxylase of rat liver: An insulin sensitive enzyme

Four lines of evidence indicates that cholesterol-7α-hydroxylase (ch-7α-H, rate limiting enzyme of cholesterol catabolism) is an insulin sensitive enzyme. 1) Streptozotocin induced diabetes in the rat causes a marked increase in the hepatic activity of ch-7α-H within 24 hrs. with no further increase in subsequent days. 2) Insulin injection can rapidly (within 24 hours) suppress the elevated enzyme activity to normal levels. 3) Insulin $\text{in vitro}$ (0.02 U/ml) can directly suppress ch-7α-H activity in isolated rat liver microsomes or in liver homogenates. 4) Upon exposure to insulin, microsomal ch-7α-H activity showed a reduced stimulatory response to post-microsomal supernatant factors. These studies suggest that a) ch-7α-H is an insulin sensitive enzyme and b) insulin might have a direct role in suppressing ch-7α-H activity in rat liver.     

Biomedical and therapeutic potential of exopolysaccharides by Lactobacillus paracasei isolated from sauerkraut: Screening and characterization

The intention of the study was evaluated for purification and characterization of exopolysaccharides from Lactobacillus paracasei; was isolated from homemade Sauerkraut sample collected from Sivakasi, Tamil Nadu, India, confirmed by biochemical and gene sequencing (16S rRNA). The purification and characterization of exopolysaccharides from candidate bacterium were studied on appearance, solubility of the EPS, carbohydrate estimation, emulsifying activity, sulphate, protein, uronic acid content, FTIR, HPLC and GC-MS analysis. The percentage of elemental carbon, (54.36%) hydrogen (21.74%), nitrogen (9.63%) and sulphur content (18.03%) were recorded in exopolysaccharides. The emulsification index (E24) of EPS was higher in toluene (79.20) and benzene (78.867) supplemented medium. FTIR spectrum of the candidate bacterial EPS confirmed presence of sulphate compounds, carboxyl group, and hydrogen bonded compounds etc. EPS exhibited 76.34% of Total Antioxidant Capacity (TAC), 71.15% of reducing power, 68.65% of Hydrogen Peroxide scavenging activity and also 60.31% DPPH radical scavenging activity. The potential antioxidant properties observed in exopolysaccharides from Lactobacillus paracasei is considered as valuable drugs.     

Effect of long-term administration of estrogens on the subcellular distribution of cholesterol and the activity of rate-limiting enzymes of cholesterol biosynthesis and degradation in pigeon liver

To determine the mechanism of the hypocholesteremic effect of estrogens noted in pigeon, studies were done on the subcellular distribution of cholesterol and the activity of beta-hydroxy-beta-methylglutaryl CoA reductase (HMG-CoA reductase) and and cholesterol 7alpha-hydroxylase in pigeon liver after long-term (6 months) estrogen administration. Estrogens significantly reduced free cholesterol concentration in microsomes and mitochondrial fraction. The concentration of cholesteryl ester was reduced in the supernatant fraction. The activity of HMG-CoA reductase was significantly reduced in the estrogen-treated birds, while cholesterol 7alpha-hydroxylase activity showed no changes. Thus, the hypocholesteremic effect of estrogen noted in pigeons could be mainly due to the inhibition of cholesterol biosynthesis in the liver.