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Theses

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2000 - 200927
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Subject: Microbiology × End date: 2009 × Start date: 2000 × Type: Thesis ×
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Now showing 1 - 9 of 27
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    ThesisItemOpen Access
    Molecular characterization of the Acetobacter diazotrophicus species, isolated from native sugarcane varieties of hilly areas of Uttarakhand
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2009-07) Singh, Digar; Sharma, Anita
    Seven endophytic bacterial isolates were recovered from native sugarcane varities from hilly areas namely Berinag, Champawat and Didihat of Uttarakhand state. All the isolates along with two standard cultures – Azospirillum brasilense and Gluconoacetobacter diazotrophicus , were tested for their morphological , biochemical and molecular characterizations .All the isolates were found gram negative, rod shaped showing morphological similarity with the standard cultures. Their PGPR properties were also assessed, Bacterial isolates, Rt.Bn. and St.Bn. were IAA producing. Except St.Bn, all the isolates solubilized insoluble phosphate and produced Siderophore except Rt.Bn. Molecular characterization of the isolates was done by ARDRA profiling using four restriction enzymes, Alu I, Msp I, Hae III and Mnl I. Cluster analysis using UPGMA programme grouped the isolates as per their similarity of geographical distribution, showing insignificant similarity with the standards used. Multiple bands of nif H amplicon were observed in all the isolates (except RtChI and StCh) indicating their nitrogen fixing character.
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    ThesisItemOpen Access
    Nodulation efficacy and characterization of rhizobial isolates from Macrotyloma uniflorum (Lam.) Verdc. and Lens culinaris Medik.
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2009-07) Agrawal, Komal; Sahgal, Manvika
    Biological nitrogen fixation (BNF) is an important attribute of symbiotic association of legume host with rhizobia. To achieve maximum BNF out of any legume rhizobia association it is necessary to assess nodulation and growth promotory potential of rhizobia. Further characterization of rhizoba is must before they are available for field application. Lens culinaris and Macrotyloma uniflorum are widely cultivated in Uttarakhand as pulse and forage crops. Thirteen rhizobial isolates (five from L.culinaris & eight from M. uniflorum) were assessed for nodulation, nitrogen fixation ability and growth efficacy on homologous host and heterologous host (Glycine max). These isolates were further characterized on the basis of cultural, biochemical and DNA fingerprinting techniques. Plate assays were performed for phosphorous solubilization and siderophore production. All five isolates from nodulated L.culinaris variety VL-507 but not G.max variety VL-63. Based on nodulation potential M.uniflorum isolates were placed in two groups, one (GR5, GR6, GR7, GR8) which nodulated M.uniflorum variety VLG-8 and second (GR1, GR2, GR3, GR4) which nodulated G.max variety VL-63. All L. culinaris isolates were fast growing with generation time in the range 1.95-2.25h and produced acid on bromothymol blue indicator plates. M.uniflorum isolates were placed in two groups based on generation time, fast growing (generation time 1.97-2.01h) and slow growing (generation time 6.80-7.046h).UPGMA dendrogram based on ARDRA of 16S with Alu I, Msp I & TaqI revealed that five L.culinaris isolates were genetically diverse and represented by three rDNA types. None of the rDNA type was related to Rhizobium leguminosarum bv. trifolii strain RCl2 39. M.uniflorum isolates were placed in two clusters none of the cluster were related to Bradyrhizobium elkanii strain USDA 76 & Bradyrhizobium japonicum strain USDA 06. Majority of the isolates were positive for solubilization of phosphorous and few isolates (GR1, GR3, GR5 and GR6) were positive for siderophore production.
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    ThesisItemOpen Access
    Biodegradation of chlorinated hydrocarbons using microorganisms of industrial contaminated sites
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2007-07) Singh, Malook; Sharma, Anita
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    ThesisItemOpen Access
    Phosphate solubilizing Trichoderma sp. in bamboo (Bambusa sp.) rhizosphere
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2005-06) Pant, Aakanksha; Tewari, Lakshmi
    Trichoderma sp. is a well-known biological control agent but very little work has been done on the nutrient solubilization potential especially P-solubilization. Therefore, to describe Trichoderma haying dual potential i.e. antagonistic property against fungal phytopathogens as well as P-solubilization, the present investigation was carried out. A total of eight isolates of bamboo rhizosphere along with standard culture of Tharzianum were used in present study. All the isolates depicted a differential degree of in-vitro antagonistic potential against chick- pea wilt pathogens viz., Sclerotium rolfsii and Rhizoctonia solani inhibiting mycelia] growth of the two pathogens in dual culture plates. The various isolates formed mycelium on PDA with differential intensities of sporulation. When tested for their in-vitro phosphate solubilization using TCP (5g/L) all the isolates were found to have immense potential but of varying degrees. All the isolates solubilized higher concentrations of TCP i.e., from 5 to 30 g/L. Extra-cellular acid-- and alkaline phosphatase enzyme activities were found to be higher than acid phospha lase. Alkaline phosphatase enzyme activities were found to increase with increasing concentration of TCP (from 5 to 30 g/L). The isolate BFH-3 showed 7.06 and 11.2:5 U/ml enzyme activity (alkaline) at 5 and 30 g/L of TCP respectively. Isozyme analysis by activity staining depicted two isoforms of alkaline phosphatases produced by BRH•3 and BRP--1 in presence of 30 g/L TCP.
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    ThesisItemOpen Access
    Screening of yeast isolates for alcohol dehydrogenase activity and bioethanol production
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2005-07) Gupta, Nidhi; Tewari, Lakshmi
    Depleting fossil energy resources and the associated environmental pollution and hazardous impacts demand more ecofriendly alternative- renewable sources of energy. Therefore, attempts were made for bioethanol production by microbial fermentation of sugarcane (Saccharum officinarum) juice. Different strains of yeast (Saccharomyces) and bacteria were isolated from fresh date palm (Phoenix dactylifera) sap collected from different trees. The isolates were characterized using morphological and biochemical markers and compared with the standard culture of Saccharomyces cerevisiae ATCC 9763. All the yeast cultures were analyzed for their colonial and cellular characteristics, growth rate and total protein contents. All the isolates were analyzed for their in vitro alcohol dehydrogenase (ADH) activity and ethanol tolerance efficiency (ranging from 0 to 15% ethanol). The sugars present in sugarcane juice were identified by Thin Layer Chromatography technique. The isolates were evaluated for their ethanol producing capacity upon fermentation of sugarcane juice and the alcoholic contents in fermented juice samples were determined by Gas Liquid Chromatography (GLC) technique. All the strains were capable of producing ethanol but with varying degrees. The isolates also sowed variability towards ethanol tolerance and ADH activity. The potential strains having high ethanol producing capacity and high ethanol tolerance limits were selected for alcoholic fermentation and bioethanol production.
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    ThesisItemOpen Access
    Genetic characterization of root nodule isolates from clones of Dalbergia sissoo
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2003-08) Samant, Mukesh; Johri, B.N.
    Dalbergia sissoo (Shisham) is an important Leguminous nitrogen fixing tree of tropics. Legume-Rhizobium symbiosis is important for nitrogen fixation. Therefore, present investigation was undertaken to study the genetic diversity of rhizobial partner of Dalbergia sissoo based on biochemical and molecular tools e.g., 16 S ARDRA, IGS ARDRA, BOX PCR profiling and Nif H amplification. ARDRA of 16 S rDNA region of isolates from clones of Dalbergia sissoo (CPT 5 and CPT 6) resulted in placement of all six isolates in separate group from other authentic rhizobial and Shisham isolates. IGS ARDRA showed higher diversity within these isolates than 16 S ARDRA. UPGMA cluster analysis of combined IGS and 16 S ARDRA showed diversity within the isolates of CTP 5 (DS 5 1a and DS 5 1b) and CPT 6 (DS 6 1a, DS 6 1b, DS 6 1c and DS 6 1d) but they clustered in the same group. None of the isolate was identical to other authentic rhizobial strain and other Shisham isolates. BOX PCR profile showed some identical band pattern in all the isolates. All isolates were Nif H positive suggesting operation of nitrogenase. DNA sequencing of these isolates will permit taxonomic identification and further phylogenetic assignment.
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    ThesisItemOpen Access
    Screening of isolates of Saccharomyces sp for bioethanol production from damaged chiku (Achras zapota) fruits
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2004-08) Neelam; Tewari, Lakshmi
    Looking towards need for development of an alternative renewable source of energy due to depleting petroleum resources, attempts were made to utilize damaged/inferior quality sapota (Achras zapota) fruits for production of bio-ethanol by microbial fermentation. Different strains of yeast (Saccharomyces sp.) were isolated from different damaged sources viz. fruit surfaces (pear, apple), pulp (banana), sugarcane juice, curd and bakery-dough. The isolates were characterized using morphological, biochemical and physiological markers and compared with an standard culture of Saccharomyces cerevisiae ATCC 9763, MTCC 170 (CDRI). All the yeast cultures were analyzed for their colonial and cellular characteristics; growth rate and pattern in liquid and solid media were measured. The isolates were analyzed for their in vitro fermentation and utilization of different sugars, in vitro alcohol tolerance. Different sugars in sapota juice were identified by TLC. The isolates were evaluated for their alcohol producing capacity by liquid state and submerged fermentation of sapota fruits. The potential strains having high alcohol tolerance and alcohol production were selected for alcoholic fermentation of sapota fruits.
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    ThesisItemOpen Access
    Biodegradation of chlorinated hydrocarbons using microorganisms of Industrial contaminated sites
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2007-07) Singh, Malook; Sharma, Anita
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    ThesisItemOpen Access
    Characterization and conservation of bacterial gene pool for biodegradation of low and high density polyethylene
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2008-01) Satlewal, Alok; Goel, Reeta
    Screening of 78 bacterial isolates led to the selection of 13 different bacteria capable of utilizing polyethylene and its derivatives as the sole carbon source. Employing these, 5 consortia were developed indigenously and in-vitro/in-situ biodegradation experiments were carried out. Degraded samples were recovered and comparatively analyzed by FTIR, simultaneous DTA-DTG-TG and scanning electron microscopic analysis. Furthermore, 16s-rDNA sequencing was done for the identification and molecular characterization of the selected strains. Results have indicated that the mesophilic consortium, comprising of Microbacterium sp., Pseudomonas putida and Bacterium Te 68R, was showing highest biodegradation amongst the others. Starch impregnation had also increased the biodegradation up to 13% with respect to the untreated LDPE film for over 21 days. Determination of dry weight loss further supported these results. Thus, it could be concluded that relatively inert polyethylene could be degraded if proper consortium is employed.