Dairy Waste ‘Ghee Residue’ Influence Laccases Production by Pycnoporus Cinnabarinus and its Optimization.

The present study reveals that a potent laccases producer Pycnoporus cinnabarinus produces higher quantity of laccases in the Coll et al. Medium (M1 medium) and Potato dextrose broth medium (M4 medium) containing agricultural waste ‘wheat bran’ (1%w/v) after a great comparative study among the five laccases production media namely Coll et al. medium (M1 medium), Olga et al. medium (M2 medium), Slomczynski medium (M3 medium), Potato dextrose broth (PDB) medium (M4 medium) and nutrient salt medium (M5 medium). There was a tremendous increase in laccases production with alternative carbon source. There was about 265.2% increase in laccases production in M1 Medium with wheat bran (126.99±2.046 U/ml/min) which further increased by 305% (140.78±1.118 U/ml/min) after the addition of dairy waste ‘Ghee residue’. In the presence of rice bran there was a reduction in laccase production, which however improved in the presence of Ghee residue by a good 63.8% (56.96±1.005 U/ml/min) compared to the M1 medium with glucose. Similarly in case of M4 medium, there was an increase in laccases production by 45.6% with wheat bran (89.46±1.861U/ml/min) and on addition of ghee residue it increased to about 95.6% (115.00±2.048U/ml/min). The beneficial effect of ghee residue was proved by comparative study on effect of other inducers namely copper sulfate, ammonium tartrate, ethanol and peptone. The maximum production was obtained in 9 days at pH 3.0 and temperature 35°C in potato dextrose broth medium (M4) with 1% w/v wheat bran and 2% w/v Ghee residue. The presence of phenolic compounds in the Ghee residue was found to be encouraging laccases production.

Multistep mutagenic strain improvement in Aspergillus Carbonarius to enhance pectinase production potential.

Pectinase is one of the most important commercially synthesised enzyme having its application in several industrial sectors like food and beverages, fruit clarifications etc. A.carbonarius has the capacity to produce Exo-pectinase 50 U/ml by submerged fermentation process as per the previous study. The present study describes the improvement of previously identified fungal strain Aspergillus carbonarius for enhancement of pectinase production by inducing mutations using physical and chemical mutagens. Aiming to increase the potentiality in pectinase production, the parental strain was treated for three times with four mutagens - UV irradiation, Colchicine, Hydrogen peroxide and Ethidium bromide to obtain mutants. Mutants were selected based on higher enzyme activity, improved growth rates and varied morphology with increased pectinase production. All the surviving mutants were assessed quantitatively after first mutagenic treatment. The stability of the best mutants was tested by repeating the exposures for two times to obtain 3rd generation mutants. These mutants were tested quantitatively to assess the pectinase production. Of all the best mutants E8 showed maximum activity producing 65U/ml pectinase enzyme compared to wild and sister mutants. The wild strain of A. carbonarius is a low pectinase producing organism as per literature. This strain was successfully mutated to increase the productivity rate to 1.8 fold in comparison to wild strain. This overproduction and strain stability may be due to repeated mutagenic treatments.