Rhizopus microsporus var. rhizopodiformis: a thermotolerant fungus with potential for production of thermostable amylases Authors Simone C. Peixoto Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil João A. Jorge Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil Héctor F. Terenzi Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil Maria de Lourdes T.M. Polizeli Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil Keywords: Rhizopus microsporus, amylase, glucoamylase, a-amylase, thermotolerant fungi Abstract The effect of several nutritional and environmental parameters on growth and amylase production from Rhizopus microsporus var. rhizopodiformis was analysed. This fungus was isolated from soil of the Brazilian “cerrado” and produced high levels of amylolytic activity at 45°C in liquid medium supplemented with starch, sugar cane bagasse, oat meal or cassava flour. Glucose in the culture medium drastically repressed the amylolytic activity. The products of hydrolysis were analysed by thin layer chromatography, and glucose was detected as the main component. The amylolytic activity hydrolysed several substrates, such as amylopectin, amylase, glycogen, pullulan, starch, and maltose. Glucose was always the main end product detected by high-pressure liquid chromatography analysis. These results indicated that the amylolytic activity studied is a glucoamylase, but there were also low levels of α-amylase. As compared to other fungi, R. microsporus var. rhizopodiformis can be considered an efficient producer of thermostable amylases, using raw residues of low cost as substrates. This information is of technological value, considering the importance of amylases for industrial hydrolysis. Downloads PDF Published 2010-03-03 Issue Vol. 6 No. 4 (2003) Section Research Articles License Submission of a manuscript to International Microbiology implies: that the work described has not been published before, including publication in the World Wide Web (except in the form of an Abstract or as part of a published lecture, review, or thesis); that it is not under consideration for publication elsewhere; that all the coauthors have agreed to its publication. The corresponding author signs for and accepts responsability for releasing this material and will act on behalf of any and all coauthors regarding the editorial review and publication process.If an article is accepted for publication in International Microbiology, the authors (or other copyright holder) must transfer to the journal the right–not exclusive–to reproduce and distribute the article including reprints, translations, photographic reproductions, microform, electronic form (offline, online) or any other reproductions of similar nature. Nevertheless, all article in International Microbiology will be available on the Internet to any reader at no cost. The journal allows users to freely download, copy, print, distribute, search, and link to the full text of any article, provided the authorship and source of the published article is cited. The copyright owner's consent does not include copying for new works, or resale. In these cases, the specific written permission of International Microbiology must first be obtained.Authors are requested to create a link to the published article on the journal's website. The link must be accompanied by the following text: "The original publication is available on LINK at <http://www.im.microbios.org>. Please use the appropiate URL for the article in LINK. Articles disseminated via LINK are indexed, abstracted, and referenced by many abstracting and information services, bibliographic networks, subscription agencies, library networks, and consortia.
