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A bacterial strain capable of biotransformation of lantadene A (22beta -angeloyloxy-3-oxo-olean-12-en-28-oic acid), the pentacyclic hepatotoxin of lantana ( Lantana camara var. aculeata) has been isolated from soil using lantadene A as the sole carbon source. The organism isGram negative, rod shaped, motile, catalase positive and has been identified as Alcaligenes faecalis. The isolate has been found to be specific for lantadene A and did not utilize lantadene B. In studies using sucrose as an additional carbon source, A. faecalis elicited biotransformation of lantadene A to its trans isomer 22 beta -tigloyloxy-3-oxoolean-12-en-28-oic acid, designated as lantadene X and two otherminor metabolites which could not be isolated in pure state. [ABSTRACT FROM AUTHOR]

This study reports characterization of fibrolytic enzymes from rumen bacteria of migratory Gaddi sheep in North- West Himalayan Region (NWHR). A total of 70 cellulolytic bacteria were isolated. Two isolates viz., CDB1 and CDB5 due to higher secretion of fibrolytic enzymes, namely endoglucanase and β-glucosidase were studied. The endoglucanase and βglucosidase activities in isolate CDB1 and isolate CDB5 were found to be 0.720 and 0.696 U/mL and 0.820 and 0.758 U/mL, respectively. The isolate CDB1showed optimal enzyme production using yeast extract, while isolate CDB5 used peptone as nitrogen source for production of the enzyme. The endoglucanase (0.720 and 0.750 U/mL) and βglucosidase (0.710 and 0.722 U/mL) activities in CDB1 and CDB5 were optimal at 40°C and 50°C, respectively. Highest level of endoglucanase (0.742 and 0.850 U/mL) and βglucosidase activities (0.724 and 0.810 U/mL) produced by CDB1 and CDB5 were detected at pH 6.0 to 7.0, and 6.0 to 8.0, respectively. In view of ability of the isolates to inhibit some undesirable microorganisms, and activity of enzymes produced at 40°C and 50°C, it is envisaged that these isolates may have applications as probiotics and additives in silage making. [ABSTRACT FROM AUTHOR]

In the present study, different transcripts of Trichoderma harzianum ThHP-3 were evaluated for their response against four fungal pathogens Fusarium oxysporum, Colletotrichum capsici, Colletotrichum truncatum and Gloesercospora sorghi using RT-qPCR. The time course study of T. harzianum transcripts related to signal transduction, lytic enzymes, secondary metabolites and various transporters revealed variation in expression against four fungal pathogens. In a broader term, the transcripts were upregulated at various time intervals but the optimum expression of cyp3, abc, nrp, tga1, pmk, ech42 and glh20 varied with respect to host fungi. Additionally, the expression of transcripts related to transporters/cytochromes was also observed against Fusarium oxysporum after 96h whereas transcripts related to secondary metabolites and lytic enzymes showed significant difference in expression against Colletotrichum spp. from 72 to 96h. This is first study on transcriptomic response of T. harzianum against pathogenic fungi which shows their host specific response., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In the present study, endochitinase of T. harzianum isolate-ThHP3 induced against mycelium of F. oxysporum was cloned, sequenced and characterized. The complete nucleotide sequence contained an ORF of 1293bp corresponding to 430 amino acids with 46kDa molecular weight and theoretical pI 5.59. The precursor protein contained 22 amino acids long signal peptide at N terminus. The domain architecture of endochitinase showed low complexity regions, presence of 1W9P domain specific to cyclopentapeptide and lack of carbohydrate binding modules. The ligand binding site of ech46 endochitinase was constituted by 10 amino acids. The cDNA encoding ech46 endochitinase was ligated into pET28a vector and transformed to E. coli BL21. The predicted molecular weight of recombinant endochitinase without signal peptide was 49.4kDa with a theoretical pI 6.67. SDS-PAGE analysis of purified 6xHis tagged protein showed a single band of 49kDa. The refolded enzyme was active under acidic conditions with a temperature and pH optima of 50°C and 4. Km and V max for recombinant endochitinase using 4-pNP-(GlcNAc) 3 were 315.2±0.36μM and 0.140±0.08μMmin -1 , respectively and the calculated k cat was 6.44min -1 . The RT-qPCR revealed induction of ech46 by phytopathogenic fungi., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Phenolic compounds of nutraceutical importance viz., catechins (C), (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epigallocatechin-3-gallate (EGCG) and (-)-epicatechin-3-gallate (ECG) were estimated in fresh green tea shoots of Camellia sinensis (L) O Kuntze cultivar. The total polyphenols and total catechins were in the range of 219.90 to 317.81 and 140.83 to 271.39 g/kg, respectively in monthly samples of tea. The values of C, EC, EGC, EGCG and ECG in tea powders as analyzed through high performance liquid chromatography (HPLC) were in the range of 1.560 to 3.661, 13.338 to 27.766, 26.515 to 39.597, 62.903 to 102.168 and 18.969 to 39.469 mg/g, respectively. Effect of tea extracts and standard flavanols against five pathogenic bacteria viz., Listeria monocytogenes (MTCC-839), Pseudomonas aeruginosa (MTCC-741), Bacillus cereus (MTCC-1272), Staphylococcus aureus (MTCC-96) and Escherichia coli (MTCC-443), and eleven indigenous potential bacterial probiotics belonging to genera Enterococcus, Bacillus and Lactobacillus spp. obtained from fermented foods of Western Himalayas, was investigated. EGCG, ECG and EGC exhibited antibacterial activity but, C and EC did not show this activity. Tea extracts having high concentrations of EGCG and ECG were more potent in antibacterial action against bacterial pathogens. Tea extracts and standard flavan-3-ols augmented viability of potential probiotics in an order of EGCG > EGC > ECG > EC > C. Tea extracts and standard flavanols had no antibacterial activity against Escherichia coli (MTCC-443) but, in combination with probiotic culture supernatants, this activity was seen. The Kangra tea thus, exerts antibacterial effect on bacterial pathogens through EGCG, ECG and EGC constituents while stimulatory effect on growth of indigenous potential probiotics.

A low molecular mass alkaliphilic extra-cellular lipase of Bacillus cereus MTCC 8372 was purified 35-fold by hydrophobic interaction (Octyl-Sepharose) chromatography. The purified enzyme was found to be electrophoretically pure by denaturing gel electrophoresis and possessed a molecular mass of approximately 8 kDa. It is a homopentamer of 40 kDa as revealed by native-PAGE. The lipase was optimally active at 55 °C and retained approximately half of its original activity after 40 min incubation at 55 °C. The enzyme was maximally active at pH 8.5. Mg2+, Cu2+, Ca2+, Hg2+, Al3+ and Fe3+ at 1 mM enhanced hydrolytic activity of the lipase. Interestingly, Hg2+ ions synergized and Zn2+ and Co2+ ions antagonized the lipase activity. Among surfactants, Tween 80 promoted the lipase activity. Phenyl methyl sulfonyl fluoride (PMSF, 15 mM) decreased 98% of original activity of lipase. The lipase was highly specific towards p-nitrophenyl palmitate and showed a Vmax and Km of 0.70 mmol.mg⁻¹.min⁻¹ and 32 mM for hydrolysis of pNPP.

A few mixed ligand transition metal carbodithioate complexes of the general formula [M(4-MPipzcdt)x(phen)y]Y (M = Mn(II), Co(II), Zn(II); 4-MPipzcdt = 4-methylpiperazine-1-carbodithioate; phen = 1,10-phenanthroline; x = 1 and y = 2 when Y = Cl; x = 2 and y = 1 when Y = nil) were synthesized and screened for their antimicrobial activity against Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis by disk diffusion method. All the complexes exhibited prominent antimicrobial activity against tested pathogenic strains with the MIC values in the range <8-512 gmL(-1). The complexes [Mn(4-MPipzcdt)2(phen)] and [Co(4-MPipzcdt)(phen)2]Cl inhibited the growth of Candida albicans at a concentration as low as 8 µgmL(-1). The complexes were also evaluated for their toxicity towards human transformed rhabdomyosarcoma cells (RD cells). Moderate cell viability of the RD cells was exhibited against the metal complexes.

A wide range of fatty acid esters can be synthesized by esterification and transesterification reactions catalyzed by lipases in non-aqueous systems. In the present study, immobilization of a purified alkaline extra-cellular lipase of Bacillus cereus MTCC 8372 by adsorption on diatomaceous earth (celite) for synthesis of ethyl acetate via transesterification route was investigated. B. cereus lipase was deposited on celite (77% protein binding efficiency) by direct binding from aqueous solution. Immobilized lipase was used to synthesis of ethyl acetate from vinyl acetate and ethanol in n -nonane. Various reaction conditions, such as biocatalyst concentration, substrates concentration, choices of solvents ( n -alkanes), incubation time, temperature, molecular sieves (3A x 1.5 mm), and water activity(a w ), were optimized. The immobilized lipase (25 mg/ml) was used to perform transesterification in n -alkane(s) that resulted in approximately 73.7 mM of ethyl acetate at 55 degrees C in n -nonane under shaking (160 rpm) after 15 h, when vinyl acetate and ethanol were used in a equimolar ratio (100 mM each). Addition of molecular sieves (3A x 1.5 mm) as well as effect of water activity of saturated salt solutions (KI, KCl and KNO 3 ) to the transesterification efficiency has inhibitory effect. Batch operational stability tests indicated that immobilized lipase had retained 50% of its original catalytic activity after four consecutive batches of 15 h each.

A purified alkaline thermo-tolerant bacterial lipase from Bacillus cereus MTCC 8372 was immobilized on a Poly (MAc-co-DMA-cl-MBAm) hydrogel. The hydrogel showed approximately 94% binding capacity for lipase. The immobilized lipase (2.36 IU) was used to achieve esterification ofmyristic acid and isopropanol in n-heptane at 65 degrees C under continuous shaking. The myristic acid and isopropanol when used at a concentration of 100 mM each in n-heptane resulted in formation of isopropyl myristate (66.0 +/- 0.3 mM) in 15 h. The reaction temperature below or higher than 65 degrees C markedly reduced the formation of isopropyl myristate. Addition of a molecular sieve (3 A x 1.5 mm) to the reaction mixture drastically reduced the ester formation. The hydrogel bound lipase when repetitively used to perform esterification under optimized conditions resulted in 38.0 +/- 0.2 mM isopropyl myristate after the 3rd cycle of esterification.

In recent times, biotechnological applications of microbial lipases in synthesis of many organic molecules have rapidly increased in non-aqueous media. Microbial lipases are the 'working horses' in biocatalysis and have been extensively studied when their exceptionally high stability in non-aqueous media has been discovered. Stability of lipases in organic solvents makes them commercially feasibile in the enzymatic esterification reactions. Their stability is affected by temperature, reaction medium, water concentration and by the biocatalyst's preparation. An optimization process for ester synthesis from pilot scale to industrial scale in the reaction medium is discussed. The water released during the esterification process can be controlled over a wide range and has a profound effect on the activity of the lipases. Approaches to lipase catalysis like protein engineering, directed evolution and metagenome approach were studied. This review reports the recent development in the field ofnon-aqueous microbial lipase catalysis and factors controlling the esterification/transesterification processes in organic media.

A purified alkaline thermo-tolerant bacterial lipase from Pseudomonas aeruginosa MTCC-4713 was immobilized on a poly (AAc-co-HPMA-cl-MBAm) hydrogel. The hydrogel-bound lipase achieved 93.6% esterification of ethanol and propionic acid (300 mM: 100 mM) into ethyl propionate at temperature 65 degrees C in 3 h in the presence of a molecular sieve (3 angstroms). In contrast, hydrogel-immobilized lipase pre-exposed to 5 mM of HgCl2 orNH4Cl resulted in approximately 97% conversion of reactants in 3 h into ethyl propionate under identical conditions. The salt-exposed hydrogel was relatively more efficient in repetitive esterification than the hydrogel-bound lipase not exposed to any of the cations. Moreover, bound lipase exposed Hg2+ or NH4+ ions showed altered specificity towards p-nitrophenyl esters and was more hydrolytic towards higher C-chain p-nitrophenyl esters (p-nitrophenyl laurate and p-nitrophenyl palmitate with C 12 and C 16 chain) than the immobilized lipase not exposed to any of the salts. The later showed greater specificity towards p-nitrophenyl caprylate (C 8).

A novel extra-cellular lipase from Bacillus coagulans MTCC-6375 was purified 76.4-fold by DEAE anion exchange and Octyl Sepharose chromatography. The purified enzyme was found to be electrophoretically pure by denaturing gel electrophoresis and possessed a molecular mass of approximately 103 kDa. The lipase was optimally active at 45 degrees C and retained approximately 50% of its original activity after 20 min of incubation at 55 degrees C. The enzyme was optimally active at pH 8.5. Mg2+, Cu2+, Ca2+, Hg2+, Al3+, and Fe3+ at 1mM enhanced hydrolytic activity of the lipase. Interestingly, Hg2+ ions resulted in a maximal increase in lipase activity but Zn2+ and Co2+ ions showed an antagonistic effect on this enzyme. EDTA at 150 mM concentration inhibited the activity of lipase but Hg2+ or Al3+ (10mM) restored most of the activity of EDTA-quenched lipase. Phenyl methyl sulfonyl fluoride (PMSF, 15 mM) decreased 98% of original activity of lipase. The lipase was more specific to p-nitrophenyl esters of 8 (pNPC) and 16 (pNPP) carbon chain length esters. The lipase had a Vmax and Km of 0.44 mmol mg(-1)min(-1) and 28 mM for hydrolysis of pNPP, and 0.7 mmol mg(-1)min(-1) and 32 mM for hydrolysis of pNPC, respectively.

A bacterial strain capable of biotransformation of lantadene A (22 beta-angeloyloxy-3-oxo-olean-12-en-28-oic acid), the pentacyclic hepatotoxin of lantana (Lantana camara var. aculeata) has been isolated from soil using lantadene A as the sole carbon source. The organism is Gram negative, rod shaped, motile, catalase positive and has been identified as Alcaligenes faecalis. The isolate has been found to be specific for lantadene A and did not utilize lantadene B. In studies using sucrose as an additional carbon source, A. faecalis elicited biotransformation of lantadene A to its trans isomer 22 beta-tigloyloxy-3-oxoolean-12-en-28-oic acid, designated as lantadene X and two other minor metabolites which could not be isolated in pure state.

The intraperitoneal injection of Salmonella typhi into mice produced typhoid infection involving all the vital organs. Infection of liver was more persistent and progressive than in other organs. During the course of experimental infection, no humoral immune response was detected against phospholipase-A fractions upto 3 weeks after challenge, but significant cell mediated immunity (CMI) was found. Increased CMI response against protein antigens correlated well with the decreasing bacterial load, what suggested that CMI against proteins was important in pathogenesis of this disease.

Sporolactobacillus cellulosolvens (NCIMB 12173) isolated from an anaerobic digester and characterised biochemically is being reported for homofermentative lactic acid production from molasses in a batch culture. The effect of various process parameters on lactic acid production were optimized. A maximum lactic acid (24.2 g/l) and yield coefficient (0.79) was achieved using 3% (v/v) inoculum of 36 h old culture in molasses medium containing sugars (5%; w/v) supplemented with peptone (2.5 g/l) and (NH4)2SO4 (7.5 g/l), pH 6.5 at 40 degrees C after 72 h of fermentation.

The physicochemical pretreatment of ball milled rice straw with different oxidizing agents, peracetic acid, alkali-peroxide, manganese-peroxide compounds under steaming pressure were studied. The pretreatment resulted in major changes in chemical composition of rice straw. The peroxide treated substrates were found to be most susceptible to enzymatic saccharification. A maximum saccharification (77.4%) of alkaline-peroxide treated rice straw (5%, w/v) was achieved using cellulase enzyme produced by mixed cultivation of Trichoderma reesei Rut C-30 and Aspergillus ochraceus containing 1.83 FPU, 1.63 cellobiase and xylanase 2.03 IU/ml. The hydrolysate was fermented using coculture of a temperature resistant strain of Saccharomyces cerevisiae and Pachysolen tannophilus resulting in 1.5% (w/v) ethanol. The SSF of 10.0% (w/v) H2O2-MnSO4 treated straw yielded maximum ethanol (2.9%, w/v) after 72 h at 40 degrees C. As a consequence of the well-balanced cellulase production by mixed fungal culture, the supplementation of cellobiase or xylanase was not necessary in the simultaneous saccharification and fermentation process.

A hybrid process for the fermentation of rice straw hydrolysates into ethanol was designed to simultaneously utilize cellulose and hemicellulose fractions of the agro-residue. The process involved dilute acid hydrolysis (for obtaining C-5 sugars) followed by enzymatic saccharification of cellulose enriched fraction with crude cellulase produced by mixed cultures of Trichoderma reesei Rut C-30 and Aspergillus ochraceus IMI 317911. The fermentation medium containing acid and enzymatic hydrolysate mixture of pentoses and hexoses monomers was fermented with yeast coculture of Saccharomyces cerevisiae and Pachysolen tannophilus resulting in 295.0 ml ethanol/kg of rice straw. The hybrid process resulted in an efficient utilization of both cellulosic and hemicellulosic components of the rice straw for ethanol production.

The 4-5 days-old NMRI strain infant mice were orally inoculated with EB rotavirus (serotype 3). The intestinal disaccharidases activity was studied separately in three segments of the small intestine i.e. duodenum, jejunum and ileum on day 1 to 7 post inoculation (p.i.). The severity of EB rotavirus infection correlated with a significant decrease of small intestinal lactase, maltase and sucrase on day 3 p.i. The level of maltase after the initial decline increased in all the three segments of small intestine of infected mice. However, the lactase activity remained suppressed for a relatively longer period in ileum of infected mice than in controls. These enzymes began to approach to normal value by day 5 p.i., but in ileum, lactase activity continued to be severely depressed even on day 7 p.i. Rotavirus was consistently detected in intestinal contents by ELISA on days 1 to 7 p.i. The infected mice showed a significant increase in rotavirus (serotype 3)-specific serum IgG and IgM antibody level during the declining (days 5-7 p.i.) phase of infection. Diarrhoea was noted up to day 6 p.i. The protracted suppression of the lactase activity in ileum in comparison to duodenum and jejunum showed a differential tropism of EB rotavirus (serotype 3) strain to the small intestine of homologous murine model.

To know prevalence of rotavirus diarrhea subgroups and serotypes, a prospective study was conducted in rural, periurban and urban communities at Chandigarh. Weekly surveillance for diarrheal episodes was carried out in 110 families each from rural, periurban and urban localities constituting 584 children < 5 years of age from October, 1988 to February, 1991. Stool samples of 218 diarrheal episodes occurring in 115 children were subjected to rotavirus detection by ELISA. Rotavirus positive samples were further analyzed for subgroups and serotypes using specific monoclonal antibodies. Overall prevalence of rotavirus diarrhea was 4.3% (25/584). Rotavirus constituted 11.5% (25/218) of total diarrheal episodes and 22% (25/115) among the children affected with acute diarrhea. Among rural, periurban and urban communities, the overall prevalences of rotavirus diarrhea were 7.3%, 3.2% and 2.3% and episode related prevalences of 31.8%, 7.4% and 5%, respectively (chi 2 test for trend was highly significant from rural to periurban to urban localities). Forty per cent (10/25 of rotavirus positive samples were subgroup I and 60% (15/25) sub-group II. Of the 25 rotavirus strains, 40% (10) were serotype 2, 24% (n = 6) serotype 3 and 36% (n = 9) serotype 4. No definite temporal or seasonal pattern of rotavirus was observed; however, more of rotavirus diarrheal episodes (16%) occurred during winter season. Subgroups and serotypes were observed to cocirculate during the rotavirus episodes. Demonstration of serotypes in our field study imply that the vaccine to be used in our country must be cross protective to have an effective impact on rotavirus infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Infant mice (NMRI strain) showed the inhibition of hepatic extramedullary haemopoiesis by oral inoculation of a 100 ID50 dose of EB rotavirus and nucleoprotein of SA-11 rotavirus (serotype 3). The extramedullary haemopoiesis was observed by oral inoculation of surface protein VP7 of SA-11 rotavirus and in control (placebo administered) mice.

The course of Giardia lamblia infection in primary and secondary infection and early and late treated Swiss albino mice was studied. Animals treated after 3 days of infection did not show any resistance to a second challenge, whereas those treated after 9 days did show resistance to reinfection. Reinfected animals eliminated the parasites faster than the other groups. The maximum antibody levels in primary, reinfected, early and late treated groups were observed on the 20th, 10th, 20th and 15th post infection days respectively.

Activity of calmodulin and uptake of Ca2+, Na+ and Cl- was studied in control and Giardia lamblia infected mice. The activity of calmodulin was found to be significantly increased (p less than 0.001) in the experimental group as compared to control group. The uptake of Ca2+ increased significantly (p less than 0.001) while that of Na+ and Cl- decreased (p less than 0.001) in brush border membrane (BBM) vesicles from experimental group as compared to control group. In the presence of calmodulin inhibitor, trifluoperazine (TFP), the transport of Na+ and Cl- increased significantly (p less than 0.05) as compared to in the absence of inhibitor while transport of Ca2+ remained unaltered.

Preschool children of two villages of Kharar Taluka, Ropar district, Punjab (India) were screened for the prevalence of giardiasis. Cysts of Giardia lamblia were found in 35.1% of the stool samples and other parasites were rarely seen. The incidence of diarrhoea in association with G. lamblia positivity was 16.5% in subjects whose stool examination was positive on one or more than one occasion. No difference in the incidence of giardiasis could be seen in well nourished and undernourished children living in these endemic areas.