PShrestha

Prachand joined the Taylor lab in January of 2009 as a PostDoctoral fellow and left in April of 2012. He is currently a research and development scientist at EdeniQ, Inc in Visalia California.

My vision
“To lead both fundamental and applied scholarly research in bioprocessing with particular emphasis on generation of biofuels and value-added products from renewable resources and to avail research-based information, educational programs, and technologies on biorenewables to aspiring scholarly community and others for advancement in biobased economy.”

Research Interests

• Bioprocessing and microbial fermentation for biofuels and value-added products
• Biomass development: preprocessing and pretreatment of locally available feedstocks
• Cellulase enzymes and lignocellulose for advance biofuels production
• Microbial oil production for biofuels and higher value products
• Microbial product quality, co-products utilizations, water and energy optimization

Research Accomplishments
            The postdoctoral research at the Energy Biosciences Institute (EBI), University of California - Berkeley has been advantageous to learn cutting edge molecular and genomic tools/techniques. A high throughput technique for isolation of microorganisms from hundreds of environmental samples, their cultures and molecular identifications have been designed and conducted at the Taylor and Bruns Laboratory, Department of Plant and Microbial Biology. Fungal DNA extractions, PCR, nucleotide sequencing and comparison of nucleotide sequences with GenBank’s database using BLAST search tools are routine bioprospecting work in the lab. In parallel, I run biomass pretreatments (dilute acid and alkali) and numerous lignocellulose fermentation using pretreated biomass and different fungal species isolated from environmental samples. The fungi produce extracellular cellulase enzymes in-situ while growing on lignocellulose substrate, the only carbon substrate for the microbes during solid-substrate fermentation. At regular intervals, assays on sugars, proteins (and enzymes), and biomass component (cellulose, hemicellulose and lignin) are also conducted. I foresee that I can utilize such knowledge and techniques in my future biomass and bioenergy research endeavors.

            Before coming to UC Berkeley, I was affiliated with Bioprocessing Research Group at Iowa State University (Ames, IA). I had opportunities to work with different faculties and help in their research, which improved my skills in microbial fermentation techniques. I apply some of these techniques for the current postdoctoral research on high throughput fermentation that involves plant (energy crop) cell wall degradation by fungal species. My fast learning skills and broader vision for renewable energy and sustainable development research help me to revisit the fundamental knowledge of science and explore its multidimensional applicability. Over the 5 years (2004 – 2009), I have gained considerable research and outreach experience in the field of biofuels and biobased economy. A successful bio-mimicry concept was developed for efficient conversion of lignocellulosic biomass such as corn fiber and corn stover into ethanol by using wood-rot fungi – the molds which have, otherwise, been tremendously studied for damage of timber-in-service and forest pathology. At Iowa State, we developed a bioprocessing technique to use the wood-rot fungi (Phanerochaete chrysosporium and Gloeophyllum trabeum) for saccharification of cellulosic feedstock (eg corn fiber) and then convert the fermentable sugar into ethanol via fermentation using Saccharomyces cerevisiae. We improved the ethanol yield up to 32 gallons (~ 121 liters) per metric ton of corn fiber and this meant higher net ethanol production per bushel of corn. In 2006, a breakthrough was achieved where these wood-rot fungi were studied and reported for their ability to produce ethanol without using yeast when subjected to the appropriate cultivation conditions. Such research work can be extended to encompass a wider concept of integrated bioprocessing including (a) cost-effective microbial enzyme production, (b) consolidated saccharification and fermentation of lignocellulosic biomass for biofuels and bio-based products, and (c) alleviate energy, environment and economic constraints.

Publications

Refereed Journals

• Shrestha, P., Rasmussen, M.L., Khanal, S. K., Pometto, A. L., Van Leeuwen, J.(Hans).  (2008) Saccharification of corn fiber by Phanerochaete chrysosporium in solid-substrate fermentation and subsequent fermentation of hydrolyzate into ethanol. J. of Agricultural and Food Chemistry. 56 (11), 3918–3924.
• Khanal, S. K., Rasmussen, M.L., Shrestha, P., Visvanathan, C., Liu, H., Van Leeuwen, J.(Hans). (2008) Bioenergy and biofuel from wastes/residues of emerging biofuel industries. Water Environment Research, 80 (10), 1625 –1647.
• Shrestha, P., Khanal, S. K., Pometto, A. L., Van Leeuwen, J.(Hans).  (2009) Enzyme production by wood-rot and soft-rot fungi cultivated on corn fiber followed by hydrolyzate fermentation to ethanol. J. of Agricultural and Food Chemistry, 57 (10), 4156 – 4161.
• Nitayavardhana, S., Shrestha, P., Rasmussen, M.L., Van Leeuwen, J.(Hans), Khanal, S.K. (2010) Ultrasound improved ethanol fermentation from cassava chips in cassava-based ethanol plants. Bioresource Technology, 101 (8), 2741–2747
• Rasmussen, M.L., Shrestha, P., Khanal, S. K., Pometto, A. L., Van Leeuwen, J.(Hans). (2010) Sequential saccharification of corn fiber and ethanol production by the brown rot fungus Gloeophyllum trabeum. Bioresource Technology, 101(10), 3526–3533
• Shrestha, P., Khanal, S. K., Pometto, A. L., Van Leeuwen, J.(Hans).  (2010) Ethanol production via in-situ fungal saccharification and fermentation of mild alkali and steam pretreated corn fiber. Bioresource Technology (submitted).
• Shrestha, P., Szaro, T.M., Bruns, T.D., Taylor, J.W. (2011) Systematic search for cultivatable fungi that best deconstruct cell walls of Miscanthus and sugarcane in the field. Applied Environmental Microbiology 77(15): 5490–5504. doi:10.1128/AEM.02996-10.

Book Chapters

• Shrestha, P., Lamsal, B.P., Khanal, S.K. (2010) Preprocessiong of biomass for biofuel production. In Biofuel and Bioenergy from Biowastes and Lignocellulosic Biomass. Ed. Khanal, S.K. American Society of Civil Engineers-ASCE.
• Shrestha, P., Khanal, S.K., Rasmussen, M.L., Nitayavardhana, S., Van Leeuwen, J.(Hans). (2010). Value-added processing of residues from biofuel industries. In Biofuel and Bioenergy from Biowastes and Lignocellulosic Biomass. Ed. Khanal, S.K. American Society of Civil Engineers-ASCE.
• Takara, D., Shrestha, P., Khanal, S.K. (2010) Pretreatment of lignocellulosic biomass. In Biofuel and Bioenergy from Biowastes and Lignocellulosic Biomass. Ed. Khanal, S.K. American Society of Civil Engineers-ASCE.
• Lamsal, B.P., Shrestha, P., Khanal, S.K. (2010) Enzymatic hydrolysis of lignocellulose. In Biofuel and Bioenergy from Biowastes and Lignocellulosic Biomass. Ed. Khanal, S.K. American Society of Civil Engineers-ASCE.
• Khanal, S.K., Takara, D., Nitayavardhana, S., Lamsal, B.P., Shrestha, P. (2010) Ultrasound applications in biorenewables for enhanced bioenergy and biofuel production. In Green Chemistry for Environmental Sustainability. Ed. Sharma, S.K. and Mudhoo, A. CRC Press, Taylor and Francis Group.

Professional/Scientific Affiliations

• Ad-Hoc Reviewer – Bioresource Technology, Applied Biochemistry and Biotechnology, Journal of Hazardous Materials
• Member - American Society of Agricultural and Biological Engineers (ASABE)
• Member - Society for Industrial Microbiology (SIM)
• Member - American Institute of Chemical Engineers (AIChe)

Honors and Awards

• Grand Prize for University Research, American Academy of Environmental Engineers (AAEE, 2009)
• International Doctoral Student Thesis Award, MyNetResearch (2008)
• Research Excellence Award (Fall 2008), Graduate and Professional Student Senate (GPSS) Research Award (2008), Barbara Ann Herum Environmental Engineering Graduate Scholarship (2007) and Mervin D. Dougal Memorial Fellowship (2006), Iowa State University, Ames, IA
• Undergraduate Engineering Scholarship, General Cultural Scholarship Scheme, Indian Council for Cultural Relations, New Delhi, India (1999-2003)
• Shree Mahendra-Ratna Scholarship, Tribhuvan University, Nepal (1994-1996)
• Prajyan Gold Medal, Siddhartha Vanasthali Institute, Kathmandu, Nepal (1994)
• Merit Award (Gold Medal), Kathmandu Metropolitan Ward no. 13, Nepal (1994)
• Tuborg Excellence Award, Gorkha Brewery Industry, Kathmandu, Nepal (1994)