Thumbnail Image

Thesis

Browse

2010 - 201888
Reset filters
Subject: Microbiology × End date: 2018 × Start date: 2010 × Thesis Type: M.Sc ×
Reset filters

Search Results

Now showing 1 - 9 of 88
  • Thumbnail Image
    ThesisItemRestricted
    Pretreatment of paddy straw for cultivation of Vplvariella (Bull.ex Fr.) Singer
    (Punjab Agricultural University, Ludhiana, 2018) Swarthi K.; Sodhi, Harpreet Singh
    Two strains of Volvariella volvacea, VV3 and VV6 were evaluated for their mycelia growth rate and yield potential on pretreated paddy straw as substrate under Punjab conditions. Mycelial growth studies on Nutrient agar (NA) and Potato Dextrose agar (PDA) inoculated with Bacillus sp. and Delftia sp. separately revealed that bacteria had no antagonistic effect on the growth of V. volvacea. The mycelia growth rate of V. volvacea on PDA inoculated with bacterium was statistically at par with control and covered plate in 5 days whereas on NA mycelia growth covered the plate in 8 days. The effect of pretreatment of paddy straw on its chemical composition was studied with 6 different pretreatments: urea 1% (w/w), urea 0.5% (w/w), urea 0.5% (w/w)+Delftia sp. 0.5% (v/w), urea 0.5% (w/w) +Bacillus 0.5% (v/w), Delftia sp. 0.5%, Bacillus sp. 0.5% (v/w) and water 0.5% (v/w) as control. The pretreated paddy straw was analysed for proximate principles at a periodic interval of 5 days upto 20 days. Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF), Cellulose, hemicelluloses, Acid Detergent Lignin (ADL), Ash content and crude protein content were analysed. A significant decline in NDF value from 75.7% to 46 % and 34.4% was observed when urea 0.5% + Bacillus 0.5% + Delftia 0.5% were used as pretreatment of paddy straw respectively.The ADF value was significantly reduced to 23% and 33% when urea 0.5% +Delftia 0.5% and urea 0.5% + Bacillus 0.5% were used to treat paddy straw. A significant reduction in cellulose content was observed from 40% to 25% to 20% with urea 0.5%+ Delftia 0.5% and urea 0.5% + Bacillus 0.5% respectively. The hemicelluloses content recorded maximum reduction to 11.45% from 23.4% with urea 0.5% + Delftia 0.5%. There was a rapid decline in ADL with urea 0.5% + Delftia 0.5% and urea 0.5% + Bacillus 0.5% from 12.3% to 4.3% and 7% respectively. The ash and crude protein content increased with all the pretreatments. Studies on mycelia growth rate on pretreated paddy straw revealed that the addition of bacteria along with urea had improved the growth rate of both the strains of V. volvacea indicating the significant role of bacterial pretreatment in the mycelia growth of V.volvacea. Cultivation of V.volvacea strains on pretreated paddy straw had shown the maximum yield was obtained from pretreated paddy straw from VV6 (14.84 kg/ q dry straw) followed to strain VV3 (13.82 kg/q dry straw) on pretreated paddy straw. The yield from untreated (control) paddy straw was 10.5 kg/q dry straw from VV3, 12.5 kg/q dry straw from VV6. Present study revealed that pretreatment of paddy straw with urea 0.5%+Delftia sp. 0.5% gave better yield than untreated paddy straw.
  • Thumbnail Image
    ThesisItemRestricted
    Isolation and screening of sulphur oxidizing bacteria as potential biofertilizer
    (Punjab Agricultural University, Ludhiana, 2018) Hardeep Kaur; Gosal, S.K.
    The present investigation was conducted to isolate and screen sulphur oxidizing bacteria from different soil samples including FYM, compost, mulching field, rhizospheric soil of rice, wheat, sugarcane, onion, potato, maize, chick pea, fodder crops and various mustard crops. A total of 40 different sulphur oxidizing bacteria (SOB) were isolated. Most of the bacterial isolates showed irregular, flat colonies of different colour , short rods and were gram negative. Biochemical characterization of the bacterial isolates indicated that most of these were oxidase, urease, citrate and catalase positive whereas negative for MR-VP test. Functional characterization of these isolates showed that SOB10, SOB38 and SOB5 produced maximum amount of sulphate ion 13.529, 9.780 and 9.638 mM, respectively. Out of the 40 SOB isolates, twenty seven isolates were able to solubilize phosphate whereas, twenty two isolates were able to solubilize zinc. Similarly, the respective isolates were analyzed quantitatively for phosphate solubilization and highest value was recorded with isolate SOB12 (4.285 μg/ml). Thirteen, among the isolates were found with higher ammonia production and the amount of ammonia excretion ranged between 0.311-28.88 μg/ml. The maximum amount (28.88 μg/ml) of ammonia was excreted by isolate SOB15. All the isolates were able to produce IAA, while isolate SOB15 produced maximum IAA (7.57 μg/ml) followed by isolate SOB7 (7.29 μg/ml) in tryptophan supplemented medium. Three sulphur oxidizers SOB10, SOB38 and SOB5 were found superior in terms of functional characteristics and tested for their biofertilizer potential. A pot experiment was conducted to study the effect of sulphur oxidizing bacteria on soil microbial dynamics, nutrient availability, plant nutrient uptake and growth parameters. Significantly higher bacterial (108 CFU x 107 /g soil), diazotrophic (76 CFU x 105 /g soil), PSB (48 CFU x 103 /g soil) and sulphur oxidizing bacteria (59 CFU x 105 /g soil ) population was recorded with the application of SOB Mix + consortium biofertilizer. Maximum count of fungi (25 CFU x 103 /g soil) was observed in SOB Mix + 100% sulphur whereas, actinomycetes (78 CFU x 105 /g soil) in uninoculated control. It was observed that increase in dose of sulphur from 75% to 100% resulted greater effect on microbial population of soil. Maximum soil alkaline phosphatase (3.21 μg/hr/g soil), dehydrogenase (56.62μg TPF/hr /g soil) and urease (668.10 μg/hr/g soil) activity was observed where SOB Mix + consortium biofertilizer + 100% sulphur was applied. Soil available N (243.02 kg/ha), P (15.77 kg/ha), K (121.88kg/ha) and S (14.773 ppm) were found highest in treatment with SOB Mix + consortium biofertilizer +100% sulphur. Plant N (1.68 g/plant), P (0.98 g/plant), K (1.57 g/plant) and S (1.98 g/plant) uptake was recorded highest with application of SOB Mix + consortium biofertilizer + 100% sulphur. Plant growth parameters viz, plant height, root-shoot dry weight, number of primary and secondary branches were maximum in treatment having SOB Mix + consortium biofertilizer +100% sulphur. The integrated use of SOB Mix, consortium biofertilizer and 100% sulphur boosts soil health and plant growth parameters of Gobhi sarson. Hence, sulphur oxidizing bacteria as SOB Mix stood successfuly on all grounds of a potential biofertilizer.
  • Thumbnail Image
    ThesisItemOpen Access
    Fermentation of sweet sorghum grains for beer production using a traditional yeast inoculum
    (Punjab Agricultural University, Ludhiana, 2018) Kullar, Jasman; Keshani
    Beer is the most popular drink among alcoholic beverages with certain medicinal values and sorghum is one of the promising substrate for its production. In the present study, SSV-84 variety of sweet sorghum was evaluated for its beer production potential. Two yeasts viz. P1 and P2 were isolated from phaff, indigenous inoculum of North Western Himalayas and were further characterized on the basis of morphological and biochemical characteristics and were identified by ITS region sequencing as Cyberlindnera fabianii and Clavispora lusitaniae, respectively. Sc01 (KC515355) and MTCC-11815 were used as reference strains in this study. Growth kinetics studies depicted that Sc01 and P1 showed a continuous increase at OD600nm till 36 hrs. 11815 and P1 were at par for their alcohol production ability and were found to produce highest alcohol content i.e. 8.3 % (v/v) and 8.1% (v/v), respectively. Alcohol tolerance was found out to be highest i.e. 10.7 % (v/v) in case of 11815, and the lowest was at par in case of Sc01 and P2 i.e. 9.2 % (v/v) and 9.0 % (v/v), respectively. The yeast isolates used in the study were found out to be medium flocculators. The fermentation efficiency of the yeast isolates was in the range of 48-85 %. Three yeast isolates viz. 11815, P2 and Sc01 were further used for beer production. Optimum temperature was found out to be 28-30˚C and maximum alcohol was produced on 7th day of fermentation by yeast strain Sc01 (4.4% v/v) with sweet sorghum wort, 11815 produced 3.9% v/v alcohol and P2 produced 3.2% v/v alcohol. Titrable acidity of the beer produced was in the range of 0.123-0.254 %, the pH ranged between 3.2-3.6 and color of all the beer samples was light yellow. Beer produced by using Sc01 strain having 40:60 ratio of sweet sorghum: pilsner malt was considered the best on the basis of sensory evaluation followed by P2. The results of the study infer that Sc01 and P2 can be used for scale up of beer at pilot scale.
  • Thumbnail Image
    ThesisItemOpen Access
    Lactic acid bacterial fermentation of black carrots for probiotic kanji beverage
    (Punjab Agricultural University, Ludhiana, 2018) Sharma, Chetna; Sahota, Param Pal
    Traditional lactic acid fermentation of black carrots for production of Kanji often leads to the persistence and proliferation of pathogens in the stored beverage responsible for gastrointestinal disorders. In present study, ten functional lactic acid bacterial strains were used for the optimization and production of traditional beverage Kanji from black carrots (var. Punjab Black Beauty). The phenotypically, molecularly and probiotically characterized bacterial strains revealed their potential as active functional starter consortium culture. The bioprocess optimized for the preparation of lactic acid bacterial fermented Kanji beverage comprises 1% (w/v) active functional consortium starter inoculum, condiments concentration 1.5% (Salt and Rye) and dilution ratio 1:3 (Black carrot juice: water) with optimized 24 hour fermentation at 37°C. The physicochemical parameters of functional consortium fermented Kanji beverage (LAB count- 8.47log cfu mL-1) were: pH- 3.63, titrable acidity- 0.96%, TSS- 3°Brix, total sugars- 41.79mg mL-1, total reducing sugars- 27.26 mg mL-1, nutraceuticals viz. flavonoids- 40.49mg (100mL)-1, polyphenols- 42.84 mg (100mL)-1, total carotenoids- 44.10mg (100mL)-1, ascorbic acid - 115mg (100mL)-1 and minerals as ash- 0.55%. The antioxidant activity 84.45% by DPPH assay indicated that Kanji serves as an effective probiotic lactic acid fermented antioxidant beverage. The physicochemical parameters after 180 days of storage observed were: pH-3.72, titrable acidity- 1.13%, TSS- 3°B, total sugars- 39.26mg mL-1, total reducing sugars- 23.26 mg mL-1, antioxidant activity- 84.66%, flavonoids- 43.17mg (100mL)-1, polyphenols- 39.58mg (100mL)-1, carotenoids- 42.02mg (100mL)-1, ascorbic acid- 110mg (100mL)-1 and minerals as ash- 0.55% with functional starter culture consortium fermented Kanji beverage. The overall acceptability of Kanji beverage was 8.3±0.1 on nine point hedonic scale, especially appreciated for aroma and taste along with lower astringency. The functional consortia developed ensures the safety of the beverage ascertaining the microbiological safe reputation of traditionally fermented Kanji beverage, preserving the original, unique flavor of traditionally fermented vegetables and serving as non-dairy based lactic acid beverage.
  • Thumbnail Image
    ThesisItemOpen Access
    Pretreatment of Lignocellulosic Substrate for the Cultivation of Pleurotus spp.
    (Punjab Agricultural University, Ludhiana, 2018) Samandeep Kaur; Sharma, Shivani
    Pleurotus spp. can be grown on lignocellulosic materials comprised of complex cellulose, hemicellulose and lignin which need to be degraded for simple carbohydrates as nutrients for the growth of mushroom fungus. In this present study, the wheat straw and paddy straw were pre-treated with different combinations using Bacillus spp. and Delftia spp. i.e. T1-(Urea (1.0% w/w), T2-Urea (0.5% w/w), T3-Urea (0.5% w/w) + Delftia spp. (0.5% v/v), T4-Urea (0.5% w/w) + Bacillus spp. (0.5% v/v), T5-Delftia spp. (0.5% v/v), T6-Bacillus spp. (0.5% v/v), T7-Water (0.5% v/v as control)) to enhance the digestibility of straw for the maximum yield potential of Pleurotus spp. Total cellulase (1.04 U/mg and 0.43 U/mg), Cellobiohydrolase (3.16 U/mg and 2.2 U/mg), Endoglucanase(2.46 U/mg and 1.25 U/mg), Endoxylanase (1.38 U/mg and 0.96 U/mg) and Laccase activity (0.74 U/mg and 0.57 U/mg) for the Bacillus spp. and Delftia spp., respectively. No antagonistic effect of bacterial spp. was observed on the mycelial growth of P. florida and P. sajor-caju. The proximate composition of pre-treated paddy straw with T3 indicated reduction in NDF, ADF and cellulose from 78.5% to 46.7%, 56.5% to 40.1%, 35.6% to 16.1%, respectively and in wheat straw, a reduction was found from 84.6% to 65.5%, 59.8% to 39.8%, 38% to 24.4%. There was also a favourable reduction in lignin content from 9.6% to 5.1% and 12.5% to 9.6% in paddy straw and wheat straw, respectively. Treatments T1 and T2 retarded the mycelial growth of fungi. However, the growth was improved when Bacillus spp. (0.5% v/v) and Delftia spp. (0.5% v/v) were used along with Urea (0.5% w/w). Maximum yield was observed in P. florida (65.7 kg/q dry straw of mushrooms) and P. sajor-caju (61.6 kg/q dry straw of mushrooms) when wheat straw was pre-treated with T3. NFB (no./q dry straw) (5676 and 4338) were also higher compared to untreated wheat straw. The pre-treated paddy straw and wheat + paddy straw with treatment T3 also showed maximum yield in comparison to control. Thus, the use of bacterial pre-treatments along with urea has the potential to increase the degradation of the lignocellulolytic substrate for enhancing the yield potential of Pleurotus spp.
  • Thumbnail Image
    ThesisItemRestricted
    Effect of freeze tolerant baker‟s yeast on dough rising
    (Punjab Agricultural University, Ludhiana, 2018) Jaspreet Kaur; Katyal, Priya
    Among the sophisticated, ready to use frozen products, frozen dough is gaining considerable attention. So, attempt was made to improve freeze tolerance of baker‟s yeast strain by trehalose loading and cold acclimatization and to design its product formulations. Loading with 1.0M trehalose after 7 days of incubation led to increased intracellular trehalose content from 0.3% to 4.71%. Comparative freeze tolerance studies of parent and treated baker‟s yeast revealed that 14 day cold acclimatized culture exhibits maximum cell viability (193cfu/ml) under refrigerated conditions while further incubation for 21 day (167cfu/ml) and 28 day (165cfu/ml) lowered the cell viability. The 28 day cold acclimatized culture showed higher total sugar content of 36.29% followed by 1.0M trehalose loaded culture (29.44%). Maximum trehalose content (4.71%) was shown by 1.0M trehalose loaded culture. Minimum invertase (29.79 nmol/min/ml) and maximum maltase activity (627.99 nmol/min/ml) was shown by 1.0M trehalose loaded culture and 21 day cold acclimatized culture, respectively. Biomass production of baker‟s yeast was carried out at conditions pre-optimized in our laboratory:- pH-6.0, aeration-120 rpm and temperature-30⁰C using unclarified molasses as carbon source and corn steep liquor (CSL) as nitrogen source. Best dough rising ability was shown by 14 day cold acclimatized culture. Product formulation as cream yeast and dried (lyophilized and tray dried) yeast was prepared, out of which cream yeast was used in bread making while nutritional profiling of dried yeast formulations showed the presence of crude protein (23.39-28.98%), crude fat (2.14-2.73%), zinc (7.26-10.13mg/100g), iron (27.54-28.09mg/100g), phosphorus (463.9-593.44mg/100g), calcium (2913.7-5308.38mg/100g), tryptophan (0.71-1.09g/100g protein), methionine (0.73-0.83g/100g protein) and cysteine (0.38-0.4g/100g protein). The present study revealed that cold acclimatization of baker‟s yeast can improve its freeze tolerance. Among the two yeast formulations, cream yeast has been found to be suitable for use in dough rising for bread, while dried yeasts can be exploited as nutritional yeast by further testing for required parameters.
  • Thumbnail Image
    ThesisItemOpen Access
    Functional characterization of nanoparticle-rhizobia interactions in cowpea (Vigna unguiculata L.)
    (Punjab Agricultural University, Ludhiana, 2018) Harsimran Kaur; Kalia, Anu
    Analyzing and identifying the positive impact of nanomaterials (NM) on rhizobacteria is quite essential. Extensive research aimed at deciphering the beneficial as well as the ecotoxic aspects of nanoparticle(NP)-soil-plant microbe system interactions under environmental conditions is necessary to pave nano-interventions in agriculture. This study was aimed at understanding the NM-cowpea rhizobia interactions leading to alterations in their functional characteristics. Ninety-three isolates were obtained from the root nodules of nineteen genotypes of cowpea, out of which three best performers viz. CP-11-MAM-N1, CP-13-KK-N3-C1 and CP-VAR4-N1 were selected on the basis of qualitative and quantitative analysis of their functional traits. These were then evaluated for alterations in their growth and functional characteristics on supplementation of YEM broth with pre-determined concentrations of copper nanoparticles (CuNPs), nano-hydroxyapatite (nano-HA) and multi-wall carbon nanotubes (MW-CNT) along with two reference cultures. Maximum increase in growth, protein content and functional traits was reported for CP-VAR4-N1, CP-11-MAM-N1 and Burkholderia seminalis CP-RN-4 isolates with all three NMs. The best working concentrations for the three NMs were deduced i.e., CuNPs (20 μg mL-1), nanoHA (100 μg mL-1) and MWCNT (50 μg mL-1). Further, these cultures also exhibited high exopolysaccharide production compared to their growth in non-NM supplemented broth. The alginate encapsulation of the best NM+Culture/isolate was performed. In hydroponic study, these formulations enhanced vegetative parameters, protein content and root tip viability on inoculation. Maximum increase in these parameters was recorded for alginate-microbead containing CP-11-MAM-N1+CuNPs and nano-HA. Further, a field trial of these nano-biofertilizer formulations with 100% RDF indicated significant improvement in the soil chemical properties, total microbial population, soil enzymatic activities, vegetative growth and yield of cowpea cv. S-263.The total pod yield and pod quality were greatly enhanced with the alginate-microbead encapsulating Burkholderia seminalis CP-RN-4+nano-HA, giving highest protein content (776.79 mg g-1) and pod yield (20.59 t ha-1). Hence, the nano-biofertilizer combinations of CP-11-MAM-N1 and Burkholderia seminalis CP-RN-4 with CuNPs and nano-HA can be implemented for enhancing soil health, plant growth and yield parameters without any eco-nano-toxicity complications.
  • Thumbnail Image
    ThesisItemOpen Access
    Development of compost formulation based on paddy straw and maize stalks for cultivation of Agaricus bisporus
    (Punjab Agricultural University, Ludhiana, 2018) Sukhmandeep Kaur; Kapoor, S.
    Composting is carried out under aerobic thermogenesis to prepare a selective substrate for Agaricus bisporus production. Conventionally, wheat straw based synthetic compost is used for its production. Use of paddy straw as such tends to make the composting process anaerobic leading to low quality compost and low yields. In the present study, an alternative high yielding compost formulation based on paddy straw + maize stalks as a substitute to the existing wheat straw based compost has been made. The physico-chemical characteristics of the composts revealed their moisture, pH, temperature, C:N ratio to be within the range of 58.7-67.3%, 6.4-7.9, 42.1-76.4°C, 37.7:1-16.6:1 respectively. During different stages of mushroom cultivation i.e at zero day of compost, final grade compost, pin head stage, after first flush and at crop termination, the straw was analysed for proximate composition. NDF, ADF, cellulose and hemicellulose content was significantly reduced upto pin head stage and ranged from (70.20-46.20%), (52.41-33.72%), (36.37-20.69%), (17.59-8.57%) respectively and stable thereafter in all the compost. Total ash content was showed increment and ranged from 10.90-21.37%. There was no decline in the lignin content during different stages of composting and crop production. The yield data indicated that maximum yield (13.6 kg/q compost) in paddy straw + maize stalk (1:1) compost with 1563 fruit bodies/q compost. It was observed that paddy straw + maize stalk (1:1, w/w) compost was better degraded than paddy straw + maize stalk (2:1,w/w) and paddy straw composts. From the present study, it concluded that paddy straw + maize stalk (1:1, w/w) compost was the best formulation which could be further exploited for large scale production of mushrooms for small and marginal farmers.
  • Thumbnail Image
    ThesisItemRestricted
    Characterisation of rhizobacteria for growth and yield enhancement of kharif mung bean (Vigna radiata)
    (Punjab Agricultural University, Ludhiana, 2018) Oberai, Mehak; Khanna, Veena
    Forty rhizobacterial isolates were evaluated for their PGP traits at 30˚and 40°C however, it was found that rhizobacteria were better acclimatized to 30°C as compared to 40˚C. 16S rDNA sequencing that two most potent isolates belonged to genera Enterobacter and Pseudomonas. IAA production at 30°C ranging from 9.6-38.8μg/ml decreased to 5.08- 29.01μg/ml at 40°C. IAA production was confirmed by HPLC analysis by MO1, MO32 and MO33 (16.1, 9.4 and 14.8 μg/ml respectively). The isolates were potent P and Zn solubilizers with P-solubilisation index ranging from 6-48mm and Zn solubilisation index ranging from 0.5 – 46 mm at 30°C. Surprisingly, the P and Zn solubilisation index at 40°C was at par with index range at 30 °C with MO1 and MO33 showing highest rate of P (48 and 48.5 mm) and Zn (46.6 and 44.5 mm) solubilisation. The gibberellic acid production ranged from 6-150μg/ml at 30°C and 3-90μg/ml at 40°C with MO1 (150 μg/ml) being the highest gibberellic acid producer. Isolates MO1, MO32 and MO33 were HCN and ammonia producers as well. The biocidal effect of the rhizobacterial allelochemicals against F.oxysporum and R.solani was studied using the standard techniques and it was established by the SEM studies. MO1, MO32 and MO33 proved to be strong antagonistic agents bringing about substantial inhibition of the phytopathogens (22.2 – 33.3%). The study carried out showed that isolates MO1, MO32 and MO33 exhibited growth and functionality traits both at 30˚ and 40˚C which were at par, hence, enabled their selection for field trials. The field experiment conducted revealed that co-inoculation of Rhizobium and MO33 proved to be the most efficient, resulting in the improvement of both symbiotic traits viz nodule number per plant (71), nodule dry weight (21.2 mg/plant), root (1.84 g/plant) and shoot (13.10 g/plant) dry weight and the yield (1174 kg/ha) of mung bean (ML2056) as compared to the control or Rhizobium treatment alone.