African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12481

Full Length Research Paper

Evaluation of nutritional substrate and physical stress (gamma irradiation) in b-glucan productivity by mushroom (Pleurotus ostreatus)

Mohamed E. A. Dawoud1* and Amira M. Abu Taleb2
Botany Department, Faculty of Science, Cairo University, Egypt.
Email: [email protected]

  •  Accepted: 12 October 2011
  •  Published: 30 November 2011

Abstract

-Glucans present in mushrooms are bioactive polysaccharides that have many pharmacological (immuno-modulatory, antitumoral, hepatoprotector, anti- inflammatory and antioxidant) activities. The -glucans productivity of the mushroom depends upon the growing conditions, nutritional substrates, biotic and abiotic stress factors that result in an enzymes over-expression. The study shows the potential response of glucan production by fungi grown on newly designed animal plant crude (hydrolyzate) extract broth (APCEB) substrate (animal-, plant-waste crude extract broth fortified with 1g KH2PO4 l-1) and gamma irradiation. On application of physical stress factors (gamma irradiation, 1 to 6 kGy), 1 kGy gamma irradiation doses resulted in an increase in: protein (37.5%), carbohydrates (32.15%), glucans (12.0%) and growth (dry mass, 14.8%); these were due to the enhancement of low doses (1.0 kGy) of gamma irradiation upon growth and metabolism that was synergized by the radioprotective components (cysteine) that prevailed in the animal extract. This substrate supported the growth and glucan production of Pleurotus ostreatus than bySchizophyllum commune and Saccharomyces cerevisae. There are suggested procedures to assure the percentage of glucan purity and entity. The APCEB substrate is a general basic formula in which the animal and plant remains can be replaced by many others. The yield of this media economizes the glucan production. 

 

Key words: -Glucans, Pleurotus ostreatus, Schizophyllum commune, Saccharomyces cerevisae, gamma irradiation, submerged cultures and nutritional synergism.

Abbreviation

APCEB, Animal plant crude (hydrolyzate) extract broth; MYA, malt yeast extract glucose agar; CE, crude hydrolyzate extract; ACE, animal crude extract; NCRRT, national center for radiation research and technology; DRV, direct reducing value; GHL, glycerol content of hydrolyzed lipid; BOD, biological oxygen demand.