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Thirty four samples of rice bran, of which 9 were from raw (untreated) rice (RR) and 25 from parboiled rice (PbR) were collected from commercial rice mills in and around Madras and analysed for storage mycoflora and mycotoxins. Fungi of the Aspergillus flavus group were present in 29 of the 34 samples (8 from RR and 21 from PbR) in quantities ranging from less than 1-432 thousand propagules/g, though not always as the dominant mycoflora. Fungal numbers were usually higher in RR than in PbR samples. Five of the 9 RR samples and 6 of the 25 PbR samples were positive for aflatoxins. Among 29 isolates of A. flavus obtained from the bran samples, 16 isolates -6 from RR bran and 10 from PbR bran - were found to be toxigenic in vitro. Some isolates of A. candidus also seemed to produce aflatoxin and other fluorescent substances.

The purpose of this work was to evaluate the antimicrobial potential of endophytic fungi isolated from leaves and stems of Suaeda maritima and Suaeda monoica. Many endophytes were isolated by using potato dextrose agar (PDA) medium. All the endophytic isolates were identified by using standard taxonomic keys and monographs. From a total of 16 isolates, nine potent strains were taken for further study. The fungal culture was extracted with ethyl acetate and used as a crude extract for checking antimicrobial activities by well diffusion method. The crude extract showed different inhibitory activity against all pathogens, the zones of inhibition obtained was between 2 and 12 mm. SM-EF 3 crude extract showed high zone of inhibition of 11.6±0.57 mm against Salmonella typhi, 8.3±1.52 mm against Trichophyton rubrum, respectively. The present findings concludes that SM-EF 3, SM-EF 7 and SM-EF 9 showed comparatively higher antimicrobial activity against all the human pathogens. From the present work, it is possible to conclude that these microorganisms could be promising source of bioactive compounds and warrant further study.

The changes in moisture content, storage mycoflora and aflatoxin B1 (AFB1) in bran from untreated or raw rice (Rr) and parboiled rice (Pbr) stored in small lots in polyethylene bags were studied at 15-day intervals up to 60 days, using five lots of each type of bran. Deterioration was more rapid with reference to all the three parameters, in Rr bran compared to Pbr bran, the former becoming completely overgrown and caked with fungi by the end of 60 days. Aspergillus flavus was the dominant fungus in Pbr bran, whereas A. candidus and Trichoderma viride were abundant in Rr bran. The frequency of incidence as well as concentration of AFB1 increased with storage time in both types of bran, but the rate of increase as well as overall concentration were much higher in Rr bran. Thus raw rice bran is unsuitable for prolonged storage.

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