Hassan Krishnamurthy Sreenath

Biodata:

Address:
Institute for Microbial Biochemical Technology, Forest Products Laboratory, One, Gifford Pinchot Drive, Madison, Wisconsin 53705, USA

Telephone number:
(608)-231-9409, Fax number: (608)-231-9262

Academic training:
B.Sc, 1973, Chemistry, Botany, zoology, Bangalore, India
M.Sc, 1976, Zoology, Bangalore, India
Ph.D, 1981, Food science, Mysore, India

Other education and training courses:

March 22 - 24, 1983
Ultrathinlayer isoelectric focusing, Munich, Germany
March 25 -27, 1983
Preparative isoelectric focusing, Munich, Germany

Languages: English (fluent), German (reading and speaking fluency), Kannada (native fluency)

Employment history:

Jan. 1977- June 1981
Research Fellowship,Xylanase production by Streptomyces. Strain improvement, industrial use of glucose isomerase production
July 1981- Nov. 1983
Alexander von Humboldt postdoctoral fellowship, Plant tissue liquefaction and maceration by pectinases, cellulases and hemicellulases
Dec. 83 - Oct. 84
Pool officer at CFTRI, Mysore, India, Enzymatic processing of fruit
Nov. 84 - July 85
Postdoctoral fellowship, University of Wisconsin, Madison, Pentose fermentation by yeasts
Aug 85 - June 87
Postdocotral fellowship, Purdue University, West Lafayette, Indiana, Polysaccharide modification by enzymes
July 87 - Aug. 88
Assoc. Res. Sci., USDA, Winterhaven, Florida, Polysaccharide clouding agents
Jan. 89 - Sept. 93
Senior Scientist, Defense Food Research Laboratory, Mysore, India, Use of enzyme technology in food beverages
Sept.93 - present
Visiting fellow, Forest Products Laboratory, Madison, Wisconsin, Strain selection and mutation for arabinose fermentation

Research and professional accomplishments:

For graduate studies, I Isolated several novel xylanases from Streptomyces and optimized their production. Used xylanases to hydrolyze natural substrates and produced glucose isomerase. Ultimately a strain of Streptomyces was obtained by hybridization which is capable of producing glucose isomerase on natural xylan. The Streptomyces xylanases were purified and biochemically characterized.

For my Humboldt fellowship, I characterized fungal enzymes with plant tissue macerating and liquefaction activity. I fractionated crude technical enzyme preparations using high resolution analytical and preparative techniques with the aim of defining the specificity of enzymes involved in the degradation of a protopectin -cellulose substrate.

During my post-doctoral fellowship at Madison, I optimized the batch fermentation of xylose to ethanol considering several factors such as aeration, age and size of inoculum, rate of glucose addition, continuous removal of products using membrane filtration. This included pretreatment and conditioning acid hydrolyzates of wood for ethanol production.

At Purdue University, I modified several polysaccharide gums such as cellulosic gums, galacto-mannans, alginates, starch with food grade enzymes for the development of non-metabolizable low-calorie bullking agents, and extracted industrially valuable hemicelluloses from vegetable pulp wastes.

At the USDA citrus research lab, I evaluated several commercially available beverage clouding agents for their strength and stability. Citrus by-products and wastes were utilized via fermentation and enzymatic treatments and natural beverage clouding agents were produced.

Upon returning to India, I used pectinases, cellulases and hemicellulases to produce low-pulp low-viscosity mango juices from mango varieties and used enzymes to clarify blue and white grape juice, and to increase the yield of pineapple juice from fruit pulp residue. I also incorporated dietary fiber into the processed food.

Presently, I am using mutagenesis and strain screening techniques to improve the fermentation of corn processing sugar residues by various yeasts. The main focus is on arabinose fermentation. A microfuge fermentation rack was designed for screening yeast strains and mutants for alcohol production. High ethanol producing mutant strains were optimized for ethanol fermentation rates. Associating with team of molecular biologists to express genes involved in ethanol fermentation. In addition to fermentation, I am working on modification of non-wood fibers with various polysaccharases.

Special skills and expertise:

Techniques: Gas Chromatography, High pressure Liquid Chromatography, Gel chromatography, Ultra thin layer Isoelectricfocussing, Preparative Isoelectricfocusing, Spectrophotometry, Bench-scale fermentor operation, mutation techniques, Macintosh operating system, Microsoft Excel, Word and graphics. Teaching carbohydrate chemistry for post graduate courses.

References:

Send comments concerning this page to Tom Jeffries twjeffri@facstaff.wisc.edu
Tom Jeffries
Last edited December 2, 1995

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