Co-encapsulation of lactic acid bacteria and prebiotic with alginate-fenugreek gum-locust bean gum matrix: Viability of encapsulated bacteria under simulated gastrointestinal condition and during storage time

The aim of this study was to enhance the viability of probiotic strains Pediococcus pentosaceus KID7, Lactobacillus plantarum KII2, Lactobacillus fermentum KLAB6 and Lactobacillus helveticus KII13 in gastrointestinal transit, freeze-drying condition and during storage time by microencapsulation using a combination of alginate, fenugreek gum and locust bean gum. The microcapsules were prepared using various ratio of alginate to fenugreek gum to locust bean gum and tested for its dissolution in colonic fluid. The combination that efficiently dissolved in colonic fluid was selected for co-encapsulation of the probiotic strains and prebiotics to produce synbiotic microcapsules. Further, we observed that the bacteria encapsulated with alginate-fenugreek gum-locust bean gum (AFL) matrix tolerated gastrointestinal condition efficiently compared to non-encapsulated bacteria. The encapsulated bacterial cells retained higher viability than non-encapsulated cells during freeze-drying condition and subsequent storage for 3 months at 4°C. These results show the utility of AFL matrix in microencapsulation of probiotics for use in food industry.     

H4R activation utilizes distinct signaling pathways for the production of RANTES and IL-13 in human mast cells

Context: The histamine H4 receptor functionally expressed on human mast cells and their signaling pathways for the production of IL-13 and RANTES have never been analyzed side by side in a directly comparable manner.

Objective: Therefore, the aim of the study was to investigate signaling transduction pathways of H4R via ERK1/2, Akt and NFκB leading to the induction of inflammatory cytokine expression.

Materials and methods: In the present study, HMC-1 cells and CBMCs were pretreated individually with H4R antagonist JNJ7777120, H1R antagonist mepyramine and signaling molecule inhibitors PD 98059, LY294002, Bay 117082 followed by stimulation was done with or without histamine or 4-MH. Furthermore, the siRNA mediated H4R gene silencing effects are studied at the H4R protein expression level and also signal transduction level.

Results: We found that the pretreatment with JNJ7777120 and H4R gene silencing decreased histamine, 4-MH induced phosphorylation of ERK1/2, Akt and NFκB-p65. Moreover, PD 98059, LY294002 and Bay 117082, which respectively inhibited the histamine and 4-methylhistamine induced phosphorylation of ERK1/2, Akt and NFκB-p65 respectively. We also found that the activation of H4R caused the release of IL-13 and RANTES on human mast cells. The MEK inhibitor PD98059 blocked H4R mediated RANTES/CCL5 production by 20.33?pg/ml and inhibited IL-13 generation by 95.71?pg/ml. In contrast, PI3 kinase inhibitor LY294002 had no effect on 4-MH induced RANTES/CCL5 production but blocked IL-13 generation by 117.58?pg/ml.

Discussion and conclusion: These data demonstrate that the H4R activates divergent signaling pathways to induce cytokine and chemokine production in human mast cells.     

Biotransformation of progesterone to 14 alpha-hydroxypregna-1,4-diene-3,20-dione, a novel fungal metabolite, by Colletotrichum antirrhini

The fermentation of progesterone by Colletotrichum antirrhini SC 2144 was examined. Instead of 15 alpha-hydroxyprogesterone, the reported product, this fungus converted progesterone to androst-4-ene-3,17-dione, androsta-1,4-diene-3,17-dione, 14 alpha-hydroxyandrosta-1,4-diene-3,17-dione, 11 alpha-hydroxypregn-4-ene-3,20-dione, 14 alpha-hydroxypregn-4-ene-3,20-dione, and a hitherto undescribed compound, 14 alpha-hydroxypregna-1,4-diene-3,20-dione.     

Abundance and diversity of macroinvertebrates and fish in the Tamiraparani river, South India

Occurrence of macroinvertebrates and fish was studied at 11 stations along the course of a tropical river, Tamiraparani, South India. Monthly variations in macroinvertebrate density were studied during 1991. Among macroinvertebrates, hemipterans were the dominant group at all sites, except site 2. Using an ordination technique, density and occurrence of macroinvertebrates were correlated with dissolved oxygen, biological oxygen demand and chemical oxygen demand. A total of 36 species of fish was recorded and their diversity in undisturbed and disturbed regions of the river was compared on a spatial scale. Different diversity indices were calculated to assess fish response to pollution and to determine species richness and composition.     

Interactions of feeding rates on growth,food conversion and body composition of the freshwater catfish Mystus vittatus (Bloch)

Food intake, growth, conversion efficiency and body composition of the non-air breathing catfish Mystus vittatus (Bloch) were studied in relation to different feeding levels. Fish weighing 817.9 ± 104.00 mg was found to consume a maximum of 156.0 mg live Tubifex worm/g day^-1. Geometrically derived feeding rates of 6.75, 23.00 and 26.00 mg dry food/g live fish day^-1 represent the maintenance, optimum and maximum levels respectively. The SDA increased from 6.75 mg/g day^-1 at maintenance to 13.50 mg/g day^-1 at maximum feeding rate. Starvation brougt about increase in body water content, while there was concomitant decrease in fat and crude protein.     

Food consumption of Sarotherodon mossambicus (Trewaves) exposed to sublethal concentration of diammonium phosphate

S. mossambicus was exposed to toxic and sublethal concentrations of the fertilizer diammonium phosphate (0.2 to 1.0 g l^–1). Mortality, food utilization and growth were studied. At a concentration of 0.6 g l^–1 DAP, 100% mortality was observed within 96 h; no mortality occurred at 0.5 g l^–1; LC50 was 0.55 g l^–1. Rearing the fish in increasing sublethal concentrations of DAP, it was found that the feeding rate decreased from 25.4 mg g^–1 fish^–1 d^–1 (fish reared in DAP-free water) to 10.1 mg g^–1 d^–1 at the highest sublethal concentration (0.5 g l^–1). Growth rate was drastically reduced. At high sublethal concentrations of DAP, the fish lost reserve energy, in addition to the energy obtained from food intake for survival, as a result of increased swimming activity and opercular beats.     

Selective deacetylation of zaluzanin D using transformed Escherichia coli cultures

The use of conventional and unconventional reaction methodology for the hydrolysis of the acetate group in zaluzanin D resulted in hydration of the 11,13 exocyclic bond along with deacetylation. But the microorganism E. coli selectively cleaved the acetate group to yield zaluzanin C.     

Allosteric site-mediated active site inhibition of PBP2a using Quercetin 3-O-rutinoside and its combination

Recent crystallographic study revealed the involvement of allosteric site in active site inhibition of penicillin binding protein (PBP2a), where one molecule of Ceftaroline (Cef) binds to the allosteric site of PBP2a and paved way for the other molecule (Cef) to bind at the active site. Though Cef has the potency to inhibit the PBP2a, its adverse side effects are of major concern. Previous studies have reported the antibacterial property of Quercetin derivatives, a group of natural compounds. Hence, the present study aims to evaluate the effect of Quercetin 3-o-rutinoside (Rut) in allosteric site-mediated active site inhibition of PBP2a. The molecular docking studies between allosteric site and ligands (Rut, Que, and Cef) revealed a better binding efficiency (G-score) of Rut (?7.790318) and Cef (?6.194946) with respect to Que (?5.079284). Molecular dynamic (MD) simulation studies showed significant changes at the active site in the presence of ligands (Rut and Cef) at allosteric site. Four different combinations of Rut and Cef were docked and their G-scores ranged between ?6.320 and ?8.623. MD studies revealed the stability of the key residue (Ser403) with Rut being at both sites, compared to other complexes. Morphological analysis through electron microscopy confirmed that combination of Rut and Cefixime was able to disturb the bacterial cell membrane in a similar fashion to that of Rut and Cefixime alone. The results of this study indicate that the affinity of Rut at both sites were equally good, with further validations Rut could be considered as an alternative for inhibiting MRSA growth.     

High-efficient <Emphasis Type="Italic">Agrobacterium</Emphasis>-mediated <Emphasis Type="Italic">in planta</Emphasis> transformation in black gram (<Emphasis Type="Italic">Vigna mungo</Emphasis> (L.) Hepper)

In vitro culture and genetic transformation of black gram are difficult due to its recalcitrant nature. Establishment of gene transfer procedure is a prerequisite to develop transgenic plants of black gram in a shorter period. Therefore, genetic transformation was performed to optimize the factors influencing transformation efficiency through Agrobacterium tumefaciens-mediated in planta transformation using EHA 105 strain harbouring reporter gene, bar, and selectable marker, gfp-gus, in sprouted half-seed explants of black gram. Several parameters, such as co-cultivation, acetosyringone concentration, exposure time to sonication, and vacuum infiltration influencing in planta transformation, have been evaluated in this study. The half-seed explants when sonicated for 3 min and vacuum infiltered for 2 min at 100 mm of Hg in the presence of A. tumefaciens (pCAMBIA1304– bar) suspensions and incubated for 3 days co-cultivation in MS medium with 100 µM acetosyringone showed maximum transformation efficiency (46 %). The putative transformants were selected by inoculating co-cultivated seeds in BASTA^® (4 mg l^?1) containing MS medium followed by BASTA^® foliar spray on 15-day-old black gram plants (35 mg l^?1) in green house, and the transgene integration was confirmed by biochemical assay (GUS), Polymerase chain reaction, Dot-blot, and Southern hybridisation analyses.