FACTORS INFLUENCE ON GROWTH, DON AND NIV PRODUCTION BY TWO SPECIES OF FUSARIUM ISOLATED FROM FINGER MILLETS [ELEUSINE CORACANA L.]

Objective: The present investigations (In vitro) on an influence of different synthetic and food based [flour] media, pH, temperature and microbial nutrients on growth, Deoxynivalenol [DON] and Nivalenol [NIV] production by Fusarium aethiopicum and F. culmorum was carried out.Methods: Fusarium species associated with the finger millets were isolated and identified phenotypically and further confirmed by molecular methods by Polymerase Chain Reaction [PCR]. Monosporic seven day old F. aethiopicum and F. culmorum were grown in CYA broth and incubated at 27±2°C on rotary shaker for 21 days at 120 rpm. At the end of 21 day incubation period, cultures were harvested for determination of fungal biomass. The resultant culture filtrates were extracted twice with ethyl acetate and concentrated to get and final concentration of 1 ml in methanol and employed for RP-HPLC analysis for detection of DON and NIV production.Results: Finger millets flour medium induced the highest amount of mycelial growth, DON and NIV production by F. aethiopicum. However, F. culmorum achieved highest amount of hyphal growth, DON and NIV production under the influence of yeast extract sucrose [YES] medium. Maize flour medium, rice flour medium and sorghum flour medium was next preffered substrates. Optimum pH of 5.5-6.5 and temperature of 20-35°C for growth, DON and NIV production was observed. Both the species of Fusarium failed to grow and produce toxins at pH 2.5-3.5 and temperature of 40°C. Yeast extract was most favorable for maximum DON and NIV production, which increased with an increase in its concentration. On the other hand, malt extract and beef extract induced good growth and mycotoxin production at comparatively higher concentration in both the species of Fusarium under study.Conclusion: Comparatively food based media were the better substrates than synthetic media for both growth and DOIN and NIV production by two species of Fusarium under investigation. A positive correlation coefficient [r] on growth [0.458], DON [0.744] and NIV [0.882] was recorded among the media and both the species of Fusarium

INFLUENCE OF CARBON AND NITROGEN SOURCE ON GROWTH, DON AND NIV PRODUCTION BY TWO SPECIES OF FUSARIUM ISOLATED FROM FINGER MILLETS

Objective: Influence of different carbon [C] and nitrogen [N] source on the growth and Deoxynivalenol [DON] and Nivalenol [NIV] production by Fusarium aethiopicum and Fusarium culmorum was investigated.Methods: Seven days old monosporic cultures of F. aethiopicum strain GSKUMB [KJ21085] and F. culmorum strain GSKUMB [KJ190159] were grown in CYA broth and incubated at 27±2°C on the rotary shaker at 120 rpm for 21 days. At the end of incubation period, cultures were harvested for determination of fungal growth (biomass). The resultant culture filtrates were extracted twice with ethyl acetate and concentrated. One ml of final concentrate in methanol was employed for detection of DON and NIV with the help of RP-HPLC.Results: The highest amount of DON and NIV were produced by F. aethiopicum in the presence of D-mannose and D-galactose as C source, while the highest amount of biomass was recorded on maltose and succinic acid. F. culmorum produced maximum amount of toxins in the presence of D-glucose, D-mannitol and D-fructose. Sodium nitrate was most favorable nitrogen source as it induced maximum amount of toxins by F. aethiopicum, while L-methionine, L-asparatic acid and L-tryptophan were next preferred N source. In contrast, highest biomass of fungus was obtained with L-lysine, L-glutamine and L-tyrosine. F. culmorum produced maximum amount of toxin and biomass with potassium nitrate and L-tyrosine respectively.Conclusion: Present species of Fusarium differed varied both in toxins (DON, and NIV) and biomass production. Their response of fungi under investigation towards C and N sources is also varied.Â

Microbial transformation of albendazole

415-420Screening scale studies were performed to biotransform anthelmintic drug albendazole by using twelve bacterial strains representing six genera and five actinomycetes cultures. Among the cultures studied, Bacillus subtilis MTCC 619, Escherichia coli MTCC 118 and Klebsiella pneumoniae MTCC 109 could transform albendazole to one metabolite whereas, Enterobacter aerogenes NCIM 2695, Klebsiella aerogenes NCIM 2258, Pseudomonas aeruginosa NCIM 2074 and Streptomyces griseus NCIM 2622 could transform albendazole into two metabolites in significant quantities. The transformation of albendazole was identified by HPLC. Based on LC-MS-MS data, the two metabolites were predicted to be albendazole sulfoxide (M1) and albendazole sulfone (M2), the major mammalian metabolites reported previously. Since M1 is active metabolite, the results prove the versatility of microorganisms to perform industrially attractive chemical reactions

Studies on microbial transformation of albendazole by soil fungi

425-429 Soil enrichment technique was followed to isolate the fungi capable of performing biotransformation of albendazole. Among the 5 fungi isolated, Aspergillus fumigatus, A. niger and Penicillium chrysogenum could transform albendazole to one metabolite and Fusarium moniliforme could transform albendazole to two metabolites. The transformation was confirmed by HPLC. Based on LC-MS-MS analysis, the metabolites formed were predicted to be albendazole sulfoxide and albendazole sulfone. The results support that the soil enrichment is a promising technique for isolation of fungi with industrial applicability, viz. production of active metabolites from drugs.</smarttagtype

Culture conditions for the production of thermostable lipase by Thermomyces lanuginosus

In the present investigation lipase production by three strains of thermophilic Thermomyces lanuginosus (GSLMBKU-10, GSLMBKU-13 and GSLMBKU-14) was carried out in submerged fermentation process. Olive oil and triacetin (0.1%) were added to the basal medium, which stimulated the lipase production. The maximum lipase was produced by GSLMBKU-10 and GSLMBKU-13 in yeast extract starch medium supplemented with triacetin (0.1%). The optimum pH was recorded at 6.0, 6.5 and 7.0 by GSLMBKU-10, GSLMBKU-13 and GSLMBKU-14 respectively. T. lanuginosus GSLMBKU-10 strains failed to produce lipase at pH 8.0. The optimum temperature for lipase production was observed at 45 °C by GSLMBKU-14 and GSLMBKU-10, while that for GSLMBKU-13 was at 50 °C. The marginal temperature ranged from 45 °C to 50 °C for both lipase production and vegetative growth by the three strains of T. lanuginosus under study. In conclusion, the GSLMBKU-13 strain was comparatively superior in the production of lipase than the other two strains under investigation