SHARMA, NIVEDITAHANDA, SHWETA2017-03-242017-03-242016http://krishikosh.egranth.ac.in/handle/1/5810005869ABSTRACT Fruit compost being a highly probable source for pectinolytic microorganisms was utilized as a source for isolation of pectinolytic microorganisms. In total, 16 pectinolytic bacteria and 8 fungi have been screened from fruit compost. Among them, two bacterial strains C1 and S5 and one fungal strain C4 were selected on the basis of highest pectinase production (IU/ml) and were identified as B. parabrevis C1 |KU323596|, S. violaceoruber S5 |KX512313 | and R. sexualis C4 |KX512311|. Cultural conditions and process parameters viz. media types, pH, temperature, inoculum size, incubation time, substrate concentration, divalent ions and surfactants etc. were optimized firstly through classical one variable at a time (OVAT) followed by statistical optimization by employing central composite design of response surface methodology. The enzymes obtained from all the three strains were purified to homogeneity by following a sequential purification approach. B. parabrevis C1, S. violaceoruber S5 and R. sexualis C4 pectinase was purified to a final purification fold of 2.26, 3.31 and 2.68 respectively. Molecular weight of B. parabrevis C1 and R. sexualis C4 pectinase was 43 kDa whereas; S. violaceoruber S5 pectinase had a molecular weight of 60 kDa. Pectinase activity was found to be maximum at 50 oC and pH 6.0 for B. parabrevis C1 and R. sexualis C4 and 60 oC and pH 9.0 for S. violaceoruber S5. Pectinase from all the three strains was quite thermostable with retention of more than 50% activity after incubation of 90 min at 45-60 oC. Kinetic characteristics of pectinase from all the three strains showed that the enzyme was very efficient qualitatively as well as quantitatively. Raw pectin hydrolysis ability shown by pectinase from all the three strains is a rare feature of pectinase making it a potential candidate for industries. Purified pectinase of S. violaeceoruber S5 being most potential among all the pectinases study along with the other hydrolytic enzymes viz. cellulase and amylase was employed for the juice extraction and clarification by statistical optimization by employing central composite design of response surface methodology. Treatment 21 having pectinase 10U, Cellulase 2U, Amylase 5U at temperature 52 oC in time 60 min showed maximum apple juice yield and clarification. Further, apple juice was fermented with the inhouse probiotic strains i.e. L. reuteri F8, L. delbreuckii subsp. bulgaricus and L. plantarum F22 in different sets, and Set D having consortia of these three probiotic strains was highly nutritious having high content of ascorbic acid, phenols and proteins and was successfully accepted in its sensory evaluation. The apple juice proved to be a suitable media for the production of a fermented probiotic drink and can serve as a healthy beverage.ennullThesis