|
Description
Mushrooms contain a number of bioactive compounds associated with beneficial effects on human health. In this paper we report on the production of cellulase complex enzymes by Pleurotus ostreatus (Oyster) mushrooms in submerged culture supplemented with rice straw. The culture filtrate of Pleurotus exhibited relatively high activity of three-cellulase complex enzymes, (endoglucanase, exoglucanase and cellulase activity). A rice straw concentration of five percent yielded the highest activity (18.5 U/ml) for endoglucanase while a six percent concentration yielded higher activities of both exogllucanase and cellulase. The antibacterial and antitumor activity of a Pleurotus polysaccharide was studied as well. The polysaccharide showed strong inhibition activity against different bacterial strains in the laboratory (Mycobacterium aurum, Staphylococcus aureus, Streptococcus Sp., Acinetobacter calcoaceticus and Klebsiella oxytoca). Treatment with polysaccharide leads to an increase in the mean survival time of animals with tumors (85 days compared to 37 days for animals) and a significant reduction of tumor growth rate.
Key Words: Cellulase complex activities, Pleurotus ostreatus, antitumor, antibacterial, rice straw.
INTRODUCTION
In recent years Pleurotus has gained prominence as a type of edible mushroom in Egypt. Pleurotus species thrive over a wide range of subtropical climates and are representatives of white rot fungi, which can degrade directly the lingo cellulosic organic wastes of nature. Having the ability to produce extensive hydrolyzing and oxidizing enzymes (Ulezlo et al., 1975; Toyama and Ogawa, 1976; and Rajarathnam et al., 1979), these mushrooms yield the possibility of successful cultivation on a variety cheap substrates such as rice straw (Kaul and Janardhanon, 1970), wheat straw (Zadrazil, 1976) and banana pseudostems (Jandaik and Kapoor, 1974).
Successful utilization of cellulosic materials as a renewable carbon source is dependent on the development of economically feasible process technologies for cellulose production and for enzymatic hydrolysis of cellulosic material to low molecular weight products such as hexoses and pentoses. An enzyme called cellulase commonly degrades cellulose. This enzyme is produced by several microorganisms, commonly by bacteria and fungi (Bahkali, 1996; Magnelli and Forchiassin, 1999; Shin et al., 2000; Immanuel et al., 2006). Fungi are the main cellulose-producing organisms such as Trichoderma, Penicillium, Aspergillus Spp. etc. (Mandels and Reese 1985; Lakshmikant and Mathur 1990).
We studied the production of cellulose complex by Pleurotus ostreatus growing on rice straw as a sole carbon source, as well as the effect of rice straw concentration on the production of different enzymatic activities of the cellulose complex. The study also deals with the biological activity of polysaccharides isolated from Pleurotus ostreatus mushrooms. Cellulases (1,4-B-D glucan-glucanohydrolase, EC 3.2.1.4) are multi-enzyme complexes, comprising three main components; endo- glucanase (EC 3.2.1.4), exoglucanase (EC 3.2.1.91) and cellulase activity (filter paper activity (FPA) (3.2.1). These components have been shown to act synergistically... |
More articles from Mushroom News
Congress continues work on farm bill.(ami update), February 01, 2008
Sinden Committee requests candidates to apply., February 01, 2008
Pennsylvania mushroom growers contribute to "Plants for Troops".(indus..., February 01, 2008
Keep Farming First summit set.(mushroom NEWS flash), February 01, 2008
CCHD offers immunization outreach.(mushroom NEWS flash), February 01, 2008
Looking for additional articles?
Click here
to search our database of over 3 million articles.
|
%20%20&position=1)