Asian Journal of Bio Science

S. Vijayakumar ¹, K. Kumutha ¹, P. Santhana Krishnan ¹, H. Gopal ¹

Affiliations
1 Department of Agricultural Microbiology, Tamil Nadu Agricultural University, Coimbatore (T.N.), IN

Abstract

The laboratory experiment was conducted to investigate the effect of different concentrations of glucose ranges from 0.11 to 0.66 M and utilization pattern (7 days) was studied for lipid production in oleaginous yeast cultures. Lipid and biomass production was gradually increased in response to glucose concentration. In Rhodotorula glutinis, Rhodosporidium toruloides and Lipomyces starkeyi lipid content reached maximum as 4.55 g l^-1 (40.26 per cent), 4.25 g l^-1 (38.20 per cent) and 4.23 g l^-1 (38.10 per cent), respectively at 0.55 M of glucose concentration. Biomass content was also high as 11.30, 11.13 and 11.10 g l^-1, respectively at 0.55 M concentration. While studying the utilization pattern, consumption of glucose was started from the second day with small amount of lipid and biomass production and it was gradually increased on third and fourth days of fermentation period. Maximum amount of lipid (4.80, 4.64 and 4.61 g l^-1) and biomass (11.40, 11.26 g, 11.20 g l^-1) was recorded on fifth day of fermentation with the utilization of 0.5 M of glucose. Then decline in lipid production was observed on sixth and seventh days. At the end of fermentation Rhodotorula glutinis utilized 0.55 M of carbon and exhibited 4.56 g l^-1 of lipid and 11.30 g l^-1 of biomass.

Keywords

Oleaginous Yeast, Lipids, Biomass, Carbon Source, Glucose Utilization.

Full Text

     

P. C. Latha ¹, H. Gopal ¹

Affiliations
1 Department of Agricultural Microbiology, Tamil Nadu Agricultural University, Coimbatore (T.N.), IN

Abstract

The herbicides viz., 2,4-DEE, butachlor, pretilachlor and pyrazosulfuron ethyl were evaluated at different concentrations of 1FR (Field rate), 2FR, 5FR, 10FR and 100FR for their effect on microbial population (Fluorescent pseudomonads, spore forming bacilli ) and enzyme activities (β-glucosidase, protease, alkaline phosphatase and dehydrogenase) in laboratory microcosms. The result of the experiment revealed that butachlor, among the herbicides was more inhibitory to microbial population (7.85 to 34.20% reduction over control) and soil enzyme activities (5.03 to 19.11 % reduction over control) when compared to 2,4-DEE, pretilachlor and pyrazosulfuron ethyl. The different concentrations of herbicides also exerted significant influence on the population of bacilli. The highest population of bacilli was observed in control (5.799 log CFU g^-1 soil) followed by treatments receiving 1FR (5.786 log CFU g^-1 soil) and 2FR (5.781 log CFU g^-1 soil). concentrations of herbicides. The lowest population was recorded with the 100 FR treatments (5.743 log CFU g^-1 soil). Significant differences were also observed in the population of bacilli due to the interactive influence of herbicides and concentrations. The 1FR treatments of all herbicides recorded higher population comparable to the control, while butachlor at 100FR recorded the lowest population of 5.707 log CFU g^-1 soil.

Keywords

Fluorescent pseudomonads, Herbicides, Spore Forming Bacilli.

Full Text

     

S. Vijayakumar ¹, K. Kumutha ¹, P. Santhana Krishnan ¹, H. Gopal ¹

Affiliations
1 Department of Agricultural Microbiology, Tamil Nadu Agricultural University, Coimbatore (T.N.), IN

Abstract

The laboratory experiment was conducted to investigate the effect of different concentrations of glucose ranges from 0.11 to 0.66 M and utilization pattern (7 days) was studied for lipid production in oleaginous yeast cultures. Lipid and biomass production was gradually increased in response to glucose concentration. In Rhodotorula glutinis, Rhodosporidium toruloides and Lipomyces starkeyi lipid content reached maximum as 4.55 g l^-1 (40.26 per cent), 4.25 g l^-1 (38.20 per cent) and 4.23 g l^-1 (38.10 per cent), respectively at 0.55 M of glucose concentration. Biomass content was also high as 11.30, 11.13 and 11.10 g l^-1, respectively at 0.55 M concentration. While studying the utilization pattern, consumption of glucose was started from the second day with small amount of lipid and biomass production and it was gradually increased on third and fourth days of fermentation period. Maximum amount of lipid (4.80, 4.64 and 4.61 g l^-1) and biomass (11.40, 11.26 g, 11.20 g l^-1) was recorded on fifth day of fermentation with the utilization of 0.5 M of glucose. Then decline in lipid production was observed on sixth and seventh days. At the end of fermentation Rhodotorula glutinis utilized 0.55 M of carbon and exhibited 4.56 g l^-1 of lipid and 11.30 g l^-1 of biomass.

Keywords

Oleaginous Yeast, Lipids, Biomass, Carbon Source, Glucose Utilization.

Full Text

     

H. Gopal ¹, K. Kumutha ¹

Affiliations
1 Department of Agricultural Microbiology, Tamil Nadu Agricultural University, Coimbatore (T.N.), IN

Abstract

Plant growth promoting rhizobacteria viz., Azospirillum, Azotobacter, Bacillus and Pseudomonas were isolated from rhizosphere soil and ischolar_mains of ashwagandha plants collected from various locations in Tamil Nadu. The isolated strains were characterized by morphological, physiological and biochemical tests and were examined for nitrogen fixation, phosphate solubilization, phytohormone production, siderophore production and antagonistic activity. A pot culture experiment was conducted at the dept of Agricultural Microbiology, Tamil Nadu Agricultural University, Coimbatore. The results revealed that combined inoculation of A. lipoferum - AAs-11, Azotobacter - AAz-3, Bacillus - APb-1 and Pseudomonas fluorescens - APs-1 enhanced the biochemical constituents of ashwagandha such as chlorophyll, protein and total alkaloid contents, especially Withaferin-A.

Keywords

Rhizobacteria, Aswagandha, Withaferin-A.

Full Text

     

S. Vijaya Kumar ¹, K. Kumutha ¹, P. Santhana Krishnan ¹, H. Gopal ¹

Affiliations
1 Department of Agricultural Microbiology, Tamil Nadu Agriculture University, Coimbatore (T.N.), IN

Abstract

This study was undertaken to investigate the influence of nitrogen sources on lipid production by different yeast cultures. Among the four nitrogen sources, yeast extract and peptone showed maximum lipid production in biomass (22.85 and 20.03 per cent, respectively) and they were at par with each other, while ammonium sulphate (16.70 per cent) and sodium nitrate (13.34 per cent) exhibited poor lipid accumulation. Yeast extract containing broth supported to produce maximum lipid in Rhodotorula glutinis (23.82 per cent), followed by Rhodosporidium toruloides (22.53 per cent) and Lipomyces starkeyi (22.21 per cent). High amount of biomass as 10.20, 10.16 and 10.14 g l^-1 was also observed using yeast extract as nitrogen source, respectively of the above cultures. Further experiment on optimization of the concentrations ranging from 0.5 to 1.75 per cent revealed the production of higher lipids was under 0.75 per cent. Among the various concentrations evaluated, maximum lipid and biomass production was observed in Rhodotorula glutinis (31.3 per cent and 11.5 g l^-1), Rhodosporidium toruloides (29.72 per cent and 11.10 g l^-1) and Lipomyces starkeyi (28.50 per cent and 11.05 g l^-1), respectively at 0.75 per cent level. Reduction in biomass as well as lipid yield was observed when increase in concentrations of yeast extract beyond 1.0 per cent.

Keywords

Nitrogen, Oleaginous Yeast Cultures, Cell Biomass.

Full Text

     

H. Gopal ¹

Affiliations
1 Department of Agricultural Microbiology, Tamil Nadu Agricultural University, Coimbatore (T.N.), IN

Abstract

Rhizobacteria from different medicinal plants viz., Withania somnifera, Coleus forskohlii and Vinca rosea grown in different parts of Tamil Nadu were isolated and characterized. A pot culture experiment was conducted at the Department of Agricultural Microbiology, Tamil Nadu Agricultural University, Coimbatore. The results revealed that the rhizobacterial inoculation positively influenced the germination, vigour index, shoot and ischolar_main length, biomass, dry matter production, ischolar_main and alkaloid yield of ashwagandha. Inoculation of Azospirillumlipoferum-AAs-11, Azotobacter-AAz-3, Bacillus-APb-1 and Pseudomonas fluorescens-APs-1 as combined inoculant recorded the maximum growth and yield of ashwagandha.

Keywords

Ashwagandha, Growth Parameter, Rhizobacteria.

Full Text