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Aims Protoplast fusion between Aspergillus oryzae and Trichoderma harzianum and application of fusant in degradation of shellfish waste. Methods and Results The filamentous chitinolytic fungal strains A. oryzae NCIM 1272 and T. harzianum NCIM 1185 were selected as parents for protoplast fusion. Viable protoplasts were released from fungal mycelium using enzyme cocktail containing 5 mg ml−1 lysing enzymes from T. harzianum, 0·06 mg ml−1 β-glucuronidase from Helix pomatia and 1 mg ml−1 purified Penicillium ochrochloron chitinase in 0·8 mol l−1 sorbitol as an osmotic stabilizer. Intergeneric protoplast fusion was carried out using 60% polyethylene glycol as a fusogen. At optimum conditions, the regeneration frequency of the fused protoplasts on colloidal chitin medium and fusion frequency were calculated. Fusant showed higher rate of growth pattern, chitinase activity and protein content than parents. Fusant formation was confirmed by morphological markers, viz. colony morphology and spore size and denaturation gradient gel electrophoresis (DGGE). Conclusions This study revealed protoplast fusion between A. oryzae and T. harzianum significantly enhanced chitinase activity which ultimately provides potential strain for degradation of shellfish waste. Consistency in the molecular characterization results using DGGE is the major outcome of this study which can be emerged as a fundamental step in fusant identification. Significance and Impact of the Study Now it is need to provide attention over effective chitin degradation to manage shrimp processing issues. In this aspect, ability of fusant to degrade shellfish waste efficiently in short incubation time revealed discovery of potential strain in the reclamation of seafood processing crustacean bio-waste. [ABSTRACT FROM AUTHOR]

In present investigation, thin films of tungsten heteropolyoxometalates viz. undoped phosphotungstic acid [ H3 (PW12 O40)] and Tl+ doped phosphotungstic acid [Tl3 (PW12 O40)] were deposited at optimum deposition conditions by chemical growth process using organic and aqueous solutions of phosphotungustic acid and thallous acetate respectively. In this study, the optostructural and electrical properties of undoped and Tl+ doped tungsten heteropolyoxometalate thin films have been studied by scanning electron microscopy (SEM), atomic force microscopoy (AFM), X-ray diffraction, optical absorption, dc electrical resistivity and thermo-electric power techniques. Morphological study performed on scanning electron microscopy and atomic force microscopy shows after doping Tl+ there is formation of spherical shaped grains of Tl3 (PW12 O40) heteropolyoxometalate . X-ray diffraction study revealed that, the material is polycrystalline in nature having simple cubic spinel structure. After doping Tl+, intensity of prominent peak (311) increases and other peaks are suppressed, indicating intercalation of Tl+ in the octahedral lattice of phosphotungstate anion without change in crystal structure. The optical absorption study revealed that, there is decrease in band gap (Eg) of material after doping Tl+. DC electrical resistivity measurement study shows, after doping Tl+ the heteropolyoxometalate material Tl3 (PW12 O40) shows semiconducting behavior at lower temperature. The TEP study shows, generated voltage possesses plus sign over the whole range of temperature providing p-type semiconducting behavior. The TGA-DTA study revealed that, after doping Tl+, stability of Tl3 (PW12 O40) material increases and the material is thermally stable up to 265.12 °C. [ABSTRACT FROM AUTHOR]