JJBS Volume 6, Number 3, September .2013 ISSN 1995-6673 Pages 223 - 226 Jordan Journal of Biological Sciences Micro and Macronutrient Properties of Pleurotus ostreatus (Jacq: Fries) Cultivated on Different Wood Substrates Victor O. Oyetayo * and Olatomiwa O. Ariyo Department of Microbiology, Federal University of Technology, P.M.B. 704, Akure, Nigeria Received: January 15, 2013; Accepted March 26, 2013 Abstract The micro and macronutrient content of Pleurotus ostreatus cultivated on different woody substrates viz; Pycnanthus ongoleubis, Ceiba pentandra and Cananium sp. was investigated. Mineral analysis revealed that phosphorus had the highest value in all the minerals sampled and it value ranges between 51.97 mg/100 g to 56.77 mg/100 g while Magnesium recorded the least value of 1.69 mg/100g to 3.57 mg/100 g. Pleurotus ostreatus cultivated on woody substrate, Pycnanthus ongoleubis had higher and significantly different (P≤0.05) mineral content when compared with the other woody substrates, Ceiba pentandra and Cananium sp. The result of the proximate composition showed that Pycnanthus ongoleubis is the most suitable substrate for the cultivation of the Pleurotus mushroom based on the protein content. Amino acid analysis revealed that glutamic acid (9.01g/100 g to 10.3 g/100 g) was the most abundant amino acid in P. ostreatus. P. ostreatus cultivated on Pycnanthus ongoleubis had higher and significantly different (P≤0.05) values in all the amino acids when compared with P. ostreatus cultivated on the other woody substrates except phenlyalanine. Conclusively, Pycnanthus ongoleubis showed good potential as substrate for cultivation based on higher and significantly different (P≤0.05) mineral and proximate contents found in P. ostreatus cultivated on it. Keywords: Woody, Substrate, P. ostreatus, Micro and Macronutrients. * Corresponding author. e-mail: ovofuta@yahoo.com. 1. Introduction For centuries, mushrooms have been appreciated as sources of food nutrients and pharmacologically important compounds useful in medicine (Sagakami et al., 1991). In Eastern Countries like China and Japan, the knowledge of the use of edible and medicinal mushrooms had been passed on from one generation to the other in documented form (Oyetayo, 2011). For example, over 2,500 years ago, many medicinal mushrooms had been recorded and depicted in the earliest Chinese material medica book, Shennong Bencao Jing, and other succeeding Chinese medical book (Zhu, 2009). However, in most parts of Africa, consumption of mushrooms by many people is based on their organolleptic properties such as aroma, taste, flavour and texture and not on the nutritional and medicinal properties (Osemwegie et al., 2006). Pleurotus species are edible mushrooms commonly known as oyster mushrooms. Pleurotus species contain high amounts of -amino butyric acid (GABA) and ornithine. GABA is a nonessential amino acid that functions as a neurotransmitter whereas ornithine is a precursor in the synthesis of arginine (Manzi et al., 1999). They grow widely in the tropical and subtropical rainforests (Chirinang and Intarapichet, 2009). Oyster mushroom cultivation has increased tremendously throughout the world during the last few decades (Chang, 1999). Oyster mushroom accounted for 14.2 % of the total world production of edible mushroom in 1997 (Chang, 1999). These mushrooms can be used industrially for mycoremediation purposes. Hence, its cultivation can play an important role in managing organic wastes whose disposal has become a problem (Das and Mukherjee, 2007). The cultivation of oyster mushrooms is on any type of ligno cellulose material like straw, sawdust, rice hull and others. Presently sawdust is commonly used and is the preferred medium at commercial scale. Of the sawdust types, softwood sawdust like mango and cashew are known to be more suitable than hardwood sawdust. Hami (1990) studied different species of mushroom cultivated on sawdust of different woods and found that P. ostreatus gave the maximum yield. The different substrates used in cultivating mushrooms do have effect on the functional, organoleptic and chemical properties of mushrooms. In a study, Michael et al. (2011) reported that protein, ash, iron and phosphorus contents were high for mushrooms grown on bean straw compared to wheat straw. In the tropics, Pleurotus species