Effect of combination treatment with entomopathogenic fungi Beauveria bassiana and Nomuraea rileyi (Hypocreales) on Spodoptera litura (Lepidoptera: Noctuidaeae)

In biocontrol of insect pests, efficacy of treatment with multiple pathogens has not been frequently investigated but may have potential for effective management. The possible advantage of a combination treatment with two entomopathogenic fungi - Beauveria bassiana and Nomuraea rileyi - was assessed in laboratory bioassays on second instar Spodoptera litura. From among the fungal isolates of an epizootic population, two isolates of each fungus differing in virulence to S. litura were chosen, one highly virulent and the other with low virulence. The bioassays were carried out at either a continuous temperature of 25±1°C or at a temperature cycle of 32±2°C 8 h/21±2°C 16 h to mimic the field temperatures during the epizootic. Treatments with the two fungi were done both simultaneously and sequentially. In combination treatments at 25±1°C, in all isolate combinations, a majority of the larvae showed N. rileyi induced mycosis; the percentage mortality and speed of kill of insects in these treatments was similar to the N. rileyi isolate used in the combination treatments. At the temperature cycle of 32±2°C 8 h/21±2°C 16 h, in all combination treatments, all the dead insects exhibited B. bassiana mycosis; the mortality pattern was similar to the B. bassiana isolate used in the combination treatments. The adverse effect of high temperature on virulence of N. rileyi was however, not evident in in vitro growth assays. Combination treatment with both fungi did not have a synergistic effect on insect mortality.     

Composition and larvicidal activity of leaves and stem essential oils of Chloroxylon swietenia DC against Aedes aegypti and Anopheles stephensi

The laboratory bioassay of the essential oil and the isolated compounds from Chloroxylon swietenia against Aedes aegypti and Anopheles stephensi was carried out to evaluate the larvicidal activity. LC50 value estimated for A. aegypti and An. stephensi were 16.5 and 14.9 microg/ml and 20.2 and 19 microg/ml for leaf and stem oils, respectively. The three sesquiterpenes pregeijerene, geijerene and germacrene D were isolated and their Larvicidal activity was evaluated. Pregeijerene and geijerene were observed for the first time in the volatile constituents of C. swietenia, however, leaves contained higher amount of geijerene compared to stems.     

Angucyclines Sch 47554 and Sch 47555 from Streptomyces sp. SCC-2136: cloning, sequencing, and characterization

The entire gene cluster involved in the biosynthesis of angucyclines Sch 47554 and Sch 47555 was cloned, sequenced, and characterized. Analysis of the nucleotide sequence of genomic DNA spanning 77.5-kb revealed a total of 55 open reading frames, and the deduced products exhibited strong sequence similarities to type II polyketide synthases, deoxysugar biosynthetic enzymes, and a variety of accessory enzymes. The involvement of this gene cluster in the pathway of Sch 47554 and Sch 47555 was confirmed by genetic inactivation of the aromatase, including a portion of the ketoreductase, which was disrupted by inserting the thiostrepton gene.     

Genotypic variability among peanut (Arachis hypogea L.) in sensitivity of nitrogen fixation to soil drying

Peanuts (Arachis hypogea L.) are often grown on sandy soils and drought stress can be a major limitation on yield. In particular, loss in nitrogen fixation activity associated with soil drying might be limiting due to the need for high nitrogen amounts in both vegetative tissues and seeds of peanut. This study examined the response of nitrogen fixation of intact plants of seventeen peanut genotypes when subjected to soil drying in pots over approximately a 2-wk period. A large range in the sensitivity of nitrogen fixation to soil drying was observed among the seventeen genotypes. Genotype ICGV86015, in particular, was found to have nitrogen fixation that was especially tolerant of soil drying. Significant positive (P?<?0.0001) correlation was found between the soil water content at which nitrogen fixation began decreasing and the amino acid concentration in the leaves of severely stressed plants.     

Hypocalcemia in Pregnant Women

The objective of this study is to estimate the prevalence of hypocalcemia and its correlation with dietary intake of calcium (DICa) and urinary calcium excretion (UCaE) in pregnant women. Healthy pregnant women (n = 543) were enrolled consecutively. DICa was calculated form dietary history. Serum calcium (SCa) and 24-h UCaE was measured. Student t test and Chi-square tests were used to compare the continuous and categorical data in women with and without hypocalcemia (SCa ≤ 8.7 mg/dL). Linear regression was applied for determining the independent variables for hypocalcemia. The age and gestation (mean ± SD) were 21.9 ± 2.5 years and 18.0 ± 3.5 weeks, respectively. The body mass index (BMI; mean ± SD) was 23.3 ± 3.9 kg/m². Seventy-one percent women had an education of less than 10 years. The DICa and SCa were 325 ± 198 mg and 8.1 ± 1.5 mg/dL, respectively. The prevalence of hypocalcemia was 66.4% (362/545); all being asymptomatic. There was no significant difference in women with and without hypocalcemia in terms of weight, BMI, monthly family income, DICa, UCaE, and their obstetric outcome. Daily dietary calcium intake was less than the recommended dietary allowances. There was a high prevalence of asymptomatic hypocalcemia in pregnant women of low socio-economic status which was unrelated to their overall nutritional status and daily calcium intake. It did not have any adverse effect on the immediate pregnancy outcome.     

Multiple actions of spinophilin regulate mu opioid receptor function

Spinophilin, a dendritic spine-enriched scaffold protein, modulates synaptic transmission via multiple functions mediated by distinct domains of the protein. Here, we show that spinophilin is a key modulator of opiate action. Knockout of the spinophilin gene causes reduced sensitivity to the analgesic effects of morphine and early development of tolerance but a higher degree of physical dependence and increased sensitivity to the rewarding actions of the drug. At the cellular level, spinophilin associates with the mu opioid receptor (MOR) in striatum and modulates MOR signaling and endocytosis. Activation of MOR by opiate agonists such as fentanyl and morphine promotes these events, which feedback to suppress MOR responsiveness. Our findings support a potent physiological role of spinophilin in regulating MOR function and provide a potential new target for the treatment of opiate addiction.     

COILCHECK: an interactive server for the analysis of interface regions in coiled coils

Coiled coils are important structural modules and domains of protein-protein interactions. Further, they provide the required framework to proteins, like kinesins, myosins and SNAREs, which are either structural or involved in transport of biomolecules. We provide an interactive webserver to measure the strength of interactions between two helices involved in coiled coils. Interactions are measured using non-bonded and electrostatic interactions and the presence of hydrogen bonds and salt bridges. The sum of these interactions is expressed as psuedoenergy, whose ranges have been standardized using all structural entries that are classified to contain coiled coils. The results are displayed conveniently as energy per residue along with options to obtain detailed list of different types of interactions. This webserver can be useful to assess the strength of coiled coil regions, to recognize weak and strong regions, to rationalize the phenotypic behaviour of single residue mutations as well as to design mutation experiments. COILCHECK webserver can be accessed from http://caps.ncbs.res.in/coilcheck/.     

A study of host specificity in the entomopathogenic fungus Beauveria bassiana (Hypocreales,Clavicipitaceae)

Beauveria bassiana (Balsamo – Crivelli) Vuillemin based mycoinsecticides are used against agricultural, veterinary and medical insect pests. The fungus has a very diverse and extensive host range. Variation in virulence among isolates of B. bassiana to different insect species has been abundantly documented. Given the effect of multiple factors on virulence, it is not certain whether the observed difference in virulence can be labelled as host specificity. Environmental conditions and susceptibility of the insect population are two main factors that affect successful fungal infection. Keeping the environmental factors constant, if virulence of an isolate to different insect species and different populations within an insect species is compared, the scale of difference between the two responses can be estimated. If differences in virulence of an isolate to different insect species are greater than the difference in virulence to different insect populations within an insect species, then, the isolate can be considered as exhibiting specific preference to those insect species towards which it exhibits high virulence. To examine this feature, a worldwide sample of B. bassiana was bioassayed on nine insect species and two different populations within two insect species. Laboratory bioassays were done on: Bombyx mori (Lepidoptera), Spodoptera litura (Lepidoptera), Chilo partellus (Lepidoptera), Helicoverpa armigera (Lepidoptera), Epilachna vigintioctopunctata (Coleoptera), Mylabris pustulata (Coleoptera), Aphis craccivora (Homoptera), Maconellicoccus hirsutus (Hemiptera) and Oecophylla smaragdina (Hymenoptera). The range of variation in virulence of a B. bassiana isolate to different insect species was not more than that observed with different populations within a single insect species. B. bassiana is thus a generalist with no strict host preference. B. bassiana based biopesticide can be used as a broad spectrum insecticide against a myriad of insect pests.     

Evaluation of in vitro antimicrobial activity of leaf and stem essential oils of <Emphasis Type="Italic">Chloroxylon swietenia</Emphasis> DC.

The essential oils obtained by hydrodistillation of leaves and stems of Chloroxylon swietenia DC. were analysed by GC and GC-MS. The main components in the leaf oil were limonene, pregeijerene, geijerene and germacrene D, while stem oil was rich in limonene, methyl eugenol, pregeijerene and geijerene. The essential oils were evaluated for antimicrobial activity against two gram-positive and two gram-negative bacteria and four pathogenic fungi using agar disc diffusion technique. Subsequently, the minimum inhibitory concentration (MIC) from oils was determined by broth microdilution. Both the oils exhibited moderate to strong activities against all the organisms tested. Bacillus subtilis was most susceptible at 100 μg/ml of leaf and stem oils with inhibition zones of 15.9 and 13.1 mm respectively. Among all the fungi tested, A. niger inhibited effectively with a zone of inhibition of 14.9 and 11.5 mm for leaf and stem oils respectively. The results obtained suggest that the essential oils of the plant possess antimicrobial properties and serve as a biofriendly source of antimicrobial ingredients for the food and pharmaceutical industries.     

COD and BOD reduction from coffee processing wastewater using Avacado peel carbon

The aim of this study was the assessment of reduction of chemical oxygen demand (COD) and biological oxygen demand (BOD) of wastewater from coffee processing plant using activated carbon made up of Avacado Peels. The complete study was done in batch mode to investigate the effect of operating parameters. The results of the COD and BOD concentration reduction with avocado peel carbon (APC) and commercial activated carbon (CAC) were compared and optimum operating conditions were determined for maximum reduction. Adsorption isotherm was also studied besides the calculation of optimum treatment parameters for maximum reduction of COD and BOD concentration from effluent of the coffee processing plant. The maximum percentage reduction of COD and BOD concentration under optimum operating conditions using APC was 98.20% and 99.18% respectively and with CAC this reduction was 99.02% and 99.35% respectively. As the adsorption capacity of APC is comparable with that of CAC for reduction of COD and BOD concentration, it could be a lucrative technique for treatment of domestic wastewater generated in decentralized sectors.