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ThesisItem Open Access PRODUCTION OF BIODEGRADABLE PLASTIC FROM BACTERIA OF DAIRY SEWAGE ORIGIN(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR – 585 226, 2019-06-01) SHIVALKAR YADAV, K.; PRABHA R.Bacterial intracellular polyhydroxyalkanoates (PHAs), a potential substitute for synthetic plastic was extracted from bacteria of dairy sewage origin in the present study. The collected dairy sewage samples from dairies showed neutral pH with mean chemical and biological oxygen demand of 2566 and 1400 ppm respectively. On 2 % glucose enriched nutrient agar containing 0.3% lipophilic dye sudan black, black pin point colonies of viable PHA producing bacteria was 3.61 log10cfu/ml. Out of 26 PHA producers from dairy sewage samples, 24 were phenotyped as Bacillus licheniformis and 1 each as B. subtilis and B. thuringiensis. The highest PHA producer during screening was found to be B18 which was characterized as Bacillus licheniformis. Optimized medium for PHA production by B18 was found to be equal volumes of dairy sewage and nutrient broth containing 2 % glucose with peak production (78.8%) at 37οC/48 h from 9.46 log10cfu/ml. Extracted PHA from B18 and standard PHA showed stability at acidic, neutral and alkaline pH as well exhibited thermostability when subjected to batch pasteurization, boiling and sterilization temperatures through absorbance at 235 nm. Thin Layer Chromatography confirmed extracted compound from B18 as PHA, as retardation factor was similar to standard PHA. Fourier transform infrared spectroscopy revealed presence of CH, CO and OH groups in extracted and standard PHA. Liquid chromatography mass spectrometric analysis revealed molecular mass (m/z) of extracted PHA as 360 containing 3 monomers comparable with standard PHA. In biodegradability study of film made by incorporation of 1 % PHA with polypropylene had better weight loss of up to 79.9% in soil - nutrient broth extract at 26 οC at 90 days. Biodegradation of empty lassi stored bottles having similar composition of film in soil accounted for 88 % weight loss with viable bacterial count of 9.90 log10cfu/ml and yeast & molds of 8.50 log10cfu/ml, indicating microbial depolymerization of PHA and thus brittleness in bottles at the end of 180 days.ThesisItem Open Access PERFORMANCE OF LACTIC ACID BACTERIAL ISOLATES OF DAHI SAMPLES IN THE DEVELOPMENT OF HONEY ENRICHED PROBIOTIC LASSI(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2016-05-02) RAMACHANDRA, B.; H. MANJUNATHAIn order to prepare honey enriched probiotic lassi from potent probiotic isolates, 30 domestic dahi samples were collected from different locations of Bengaluru and screened for lactic isolates. Out of 40 lactic nature isolates, 21 lactic isolates showed varied tolerance to acid and bile. The lactobacilli isolates were tolerated more, leuconostocs, streptococci moderate and lactococci least to low acid and 0.3% bile. All the acid and bile tolerated isolates were identified to their species level phenotypically and genotypically as Lac.lactis ssp. lactis (1no) and Lac.lactis ssp. lactis bv diacetylactis (1 no), among the 13 lactobacilli isolates Lab.rhamnosus (5 nos), Lab.plantarum (3 nos), Lab.fermnetum (3 nos), in case of leuconostocs isolates as Leu. mesentroides ssp. mesentroides (3 nos) and all the streptococci as Str.thermophilus (3 nos). Further detailed probiotic tests such as antibacterial compounds production, antibiotic properties, hydrophobic nature, adhesion to microbial solvents, aggregative and coaggregative studies and adhesion to epithelial colon cells of pig revealed that isolate Lab.rhamnosus LB3 as a potential probiotic culture followed by Lab.plantarum LB9. Furthermore, to meet the commercial requirements the cultures functional properties such as diacetyl, EPS early set time, acidity and number of cell countswere also determined in addition to the probiotic nature. Considering the above parameters the five lactic cultures Lac.lactis ssp. bv diacetylactis LL12, Lab.rhamnosus LB3, Lab.delbreuckii ssp bulgaricus LB20, Leu. mesentroides ssp. mesntroides LE10 and Str.thermophilus ST2 were selected. The honey enriched probiotic lassi was prepared from these cultures at 1% inoculum level at 300C using the lassi base containing 3.0% fat, 8.5% SNF and 5% sugar. The probiotic lassi with 5% honey was adjudged as the best in the sensory evaluation which was statistically significant (P<0.05) when compare to control and with 3% and 7% honey percentage. The 5% honey added lassi shelf life was 5 days at room temperature (24±10C) and 20 days at refrigeration temperature (7±10C) with required acidity of 0.72% LA and viability of > 106 log 10 cfu/g which met the prerequisite for a probiotic product.ThesisItem Open Access BACTERIAL PROFILE OF MICROWAVE TREATED MILKS AND INDIGENOUS DAIRY PRODUCTS(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2006-10-01) MANJUNATHA. H.; P. A. SHANKARPh.D.(England), Former Director of Instruction, Dairy Science College, UAS, Hebbal, Bangalore; Professor, Department of Dairy Microbiology and Former Director of Instruction, Post Graduate Studies, KVAFSU, Bidar for his invaluable inputs and suggestions given during my study. But for his guidance and encouragement, this study would not have been possible. I extend my heartfelt gratitude to, Dr.G.S.Bhat, Dean, Dairy Science College, KVAFSU, Bangalore who served as advisory committee member. I take this opportunity to thank Dr. B.V. Venkateshaiah, Head of the Division, Dairy Science, Professor and Head, Department of Dairy Technology, Dairy Science College for his constant encouragement and support that helped in the successful completion of this dissertation. I am deeply indebted to my advisory committee member, Dr T.N Tulsidas, Professor and Head, Department of Agricultural Engineering, Agricultural College, UAS, GKVK, Bangalore for his guidance and assistance in the preparation of this thesis. I sincerely thank Dr.Lalith Achoth, Professor and Head, Department of Dairy Economics and Bussiness Management for his critical technical guidance during the preparation of this thesis. My sincere thanks to, Dr. R. Krishna, Dr. Prabha who helped me in choosing this topic and stood by me till the completion of my work and for devoting their precious time for this work, also for their assistance, co-operation, providing me all the moral support and laboratory facilities during my research work.ThesisItem Open Access MICROBIOLOGICAL AND NUTRITIONAL ASSESSMENT OF TIGER NUT (Cyperus esculentus) MILK BASED PROBIOTIC DRINK(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR – 585 401, 2021-03-01) MALASHREE, L.; PRABHA, R.Tiger nuts (Cyperus esculentus) palieo, under-utilized tubers are depot of nutrients and forms a super food. In this study a probiotic drink was prepared by blending of tiger nut milk and cow milk owing to dairy functional food. Tiger nut milk was prepared and inoculated with two probiotic strains Lactobacillus acidophilus and Bifidobacterium animalis ssp. lactis BB-12 separately. The fermentation characteristics such as titratable acidity 0.66 % LA and direct microscopic count 7.54 confirmed the dilution of tiger nuts to 1:4 ratio. Formulated the blend of tiger nut milk and cow milk to 75:25 with 0.82 % LA and DMC of 8.52 for Bifidobacterium BB-12 strain. The blended milk had pH of 6.5; viscosity 0.98 cP at 20 °C, specific gravity of 1.001g/ml; titratable acidity of 0.15 % LA, lactose content of 0.40 %, fat content of 4.02 %, protein of 2.80 % and total solid of 10.8 %. The lactose content in tiger nut milk was zero since it was lactose free. The optimized blend resulted in absence of aflatoxin detected by thin layer chromatography. The heat treatment of 85 °C /30 min scored best for blended milk with BB-12 strain. An inoculum level, 2 % of Bifidobacterium BB-12 strain yielded better titratable acidity 0.86 % LA, direct microbial count of 8.74 and best score for overall acceptability 8.25. Blended milk with 0.25 % stevia resulted in 0.85 % LA and 8.57 log10 cfu/ml and accepted with better score of 8.0 than that of 0.5 and 0.75 %. The optimum incubation period to ferment blend was 18 h at 37 °C as the culture gave ideal acidity of 0.86 % LA and biomass 8.66 log10 /ml. The study of feeding trials of tiger nut milk based probiotic drink in mice Balb/C recommended the drink as an alternative to lactose intolerants. The Adhesion index of BB-12 to porcine colonocyte was better in tiger nut milk probiotic drink (227 %).At refrigeration temperature (7±1°C) the stability of the tiger nut milk based probiotic drink was observed at 12th day with BB-12 viable count of 7.60. The by-product, tiger nut chaff was blended with maida flour (30:70) to prepare bun and acceptable with a score of 7.80.ThesisItem Open Access Performance Of Lactic Acid Bacterial Isolates Of Dahi Samples In The Development Of Honey Enriched Probiotic Lassi(Karnataka Veterinary Animal And Fisheries Sciences University, Bidar, 2016) Ramachandra, BFood Is An Inevitable Human Need For Optimum Physical And Mental Functioning Which Collectively Termed As Health And Depends On The Nutritional QualityThesisItem Open Access Bacterial Profile Of Microwave Treated Milks And Indigenous Dairy Products(Karnataka Veterinary Animal And Fisheries Sciences University, Bidar, 2006) Manjunatha. H.The Modern Tempo Of Life As Well As Increasing Number Of Working Class Require Simplified Food Preparation Time And Convenience In Usage As Well As Energy SavingThesisItem Open Access Study on Carrot Enriched Probiotic Shrikhand(Karnataka Veterinary, Animal and Fisheries Sciences University, Bidar, 2014-06-15) Mahesh S. Patil; Prabha, R.; Manjunayha, H.; Kempanna, C.; Arun Kumar, H.Shrikhand is an indigenous fermented milk product originated from Maharastra. The present study contributes to optimization of carrot enriched shrikhand using wild strains of probiotic and non-probiotic cultures with shelf study at room and refrigeration temperature. The domestic and market dahi samples collected from Bangalore showed the presence of lactococci, streptococci leuconsotoc and lactobacilli ranging from 4.80 to 6.11 log10 cfu/g. Among 15 lactic isolates obtained from dahi samples, Lactococcus lactis ssp. lactis LC1; Streptococcus thermophilus ST1; Leuconostoc mesenteroides ssp. mesenteroides LEU1 and Lactobacillus fermentum LB4 showed in-vitro acid and bile resistance. The probiotic group included Lactococcus lactis ssp. lactis LC1, Streptococcus thermophillus ST1, Leuconostoc mesenteroides ssp. mesenteroides LEU1 and Lactobacillus fermentum LB4 while non-probiotic group comprised of L. lactis ssp. lactis LC3, L. lactis ssp. lactis bv. diacetylactis LC5, S. thermophillus ST2 and L.fermentum LB2. Probiotic shrikhand prepared using heat treated whole milk(control), whole milk with carrot juice(7.5:1) and whole milk with carrot pomace (9:1) showed 27.8%, 29.3%; 30.0% yield of chakka respectively. Carrot juice enriched probiotic shrikhand scored more with overall acceptability followed by carrot pomace enriched shrikhand and control. The whole milk and carrot enriched probiotic shrikhand showed 4 days of shelf life compared to 3 days of whole milk and carrot enriched non-probiotic shrikhand at ambient temperature (29+10C) with viability of probiotic cultures of around 6 log10cfu/g. Carrot enriched probiotic shrikhand showed shelf stability upto 30 days with viability of probiotic cultures of round 5 log10cfu/g. AppeendiixThesisItem Open Access Evaluation of the Characteristics of the Wild Strains of the Lactic Isolates Obtained from Dahi(Karnataka Veterinary, Animal and Fisheries Sciences University, Bidar, 2013-08-15) Rajasekhar, P.; Manjunatha, H.; prabha, R.; Ramachandra, B.; Kempanna, C.; Venkatesh, M.Dahi is a thick, sour, well known fermented milk product of Indian house hold having heterogenous lacticacid bacteria. Lactococci, streptococci, leuconostoc, pediococci, lactobacilli belong to LAB. Temperature and inoculum majorly influence the activity of LAB during dahi preparation. The present study contributes to know about type of the microflora of dahi (50 samples, 5 from each zone) available in ten agricultural zones of Karnataka, functional characteristics of LAB isolates obtained, optimization of dahi preparation. The mean log10cfu of Lactic Acid Bacteria (LAB) in dahi samples collected from ten zones of Karnataka were 4.16, 3.68, 3.79 and 4.43 log10cfu/g for lactococci, streptococci, leuconostoc and lactobacilli respectively. The phenotypically and genotypically identified LAB isolates with functional properties as acid production by L.lactis ssp.lactis LC14; diacetyl and slime production L.mesenteroides Leu8, probiotic nature of S.thermophilus ST3 and bile resistance of L.delbrueckeii ssp.bulgaricus Lb32 were selected as they set the milk at 18 hours with good DMC and reasonable LA%.The above mentioned LAB were combined for dahi preparation at 1% inoculum showed titratable acidity of 0.63 and DMC of 8.32 with 1ppm of diacetyl; 180 ppm of exoploysacharides with sensory score of 7.6. The optimized dahi can be called as probiotic dahi due to addition of probiotic culture S.thermophilus ST3 along with other cultures. Upto 5 days and 11 days dahi stored at room temperature (240C) and refrigeration temperature (70C) was in good condition with acceptable quality.ThesisItem Open Access Characterization of Pigments from Wild Strains of Rhodotorula(Karnataka Veterinary, Animal and Fisheries Sciences University, Bidar, 2011-06-15) Shivalkar Yadav, K.; Prabha, R.; Krishna, R.; Manjunatha, H.; Venkateshaiah, B.V.; Narasimha MurathyThe main criterion for food selection is colour. Some synthetic colours are detrimental to human health and hence food industry is looking for natural pigment. Rhodotorula is a carotenoid biosynthetic yeast producing yellow or orange red colonies. The present study was taken up for characterization of Rhodotorula from various dairy environmental sources, screening the isolates for pigment production and characterization of pigment obtained. Among dairy environmental samples, air sample showed highest count (3.47 log cfu/min) followed by apple and can milk. Rhodotorula isolates of 11 were from air (3), apple (4), can milk (2) and yoghurt (2). Identification revealed 3 isolates as Rhodotorula minuta, while 2 isolates as Rhodotorula acheniorum and 6 as unidentified isolates as they did not match with identification key. All the isolates of Rhodotorula were screened for pigment production based on urea hydrolysis Rhodotorula minuta RAI3; Rhodotorula acheniorum RC2, Rhodotorula sp RA2, Rhodotorula minuta RY1 were further selected for pigment production isolated from air, can milk, apple and yoghurt respectively Sterile synthetic media Malt Yeast Extract Agar (MYEB), coconut water as liquid media and rice as solid substrate medium were used for extra and intra cellular pigment production from Rhodotorula minuta RAI3; Rhodotorula acheniorum RC2, Rhodotorula sp RA2, Rhodotorula minuta RY1. Coconut water and rice media showed maximum production of extra and intracellular pigment at 300C for 6 days. Among the 4 isolates, Rhodotorula minuta RAI3 showed maximum extra and intra cellular pigment production of 2.877μg/g and 4.412 μg/g of dry cell mass respectively. Lab pasteurization (630C/30min), boiling (1000C/10min) and sterilization (1210C/15 min) reduced the intensity of extra and intracellular pigment of Rhodotorula minuta RAI3. The pigment stability was noticed at pH 7 compared to acidic and alkaline pH. The stability of extra and intracellular pigments was observed both at room temperature (290C) and refrigeration temperature (40C) upto 15 days of storage. Three fractions with Rf values of 0.19, 0.65 and 0.84 for extracellular pigment and 0.21, 0.70 and 0.90 for intracellular pigment was noticed in thin layer chromatography with benzene: petroleum ether (95:5) as mobile phase that may reveal the presence of - carotene torularhodin and torulene based on their Rf values respectively.
