RESUMO
Olive oil industry generates huge quantities of solid olive mill wastes (SOMW), causing environmental damage. Cultivation of edible mushrooms, such as Pleurotus ostreatus is a valuable approach for SOMW valorization. A local strain mycelium (Tizi-Ouzou, Algeria) of P. ostreatus (LPO) was isolated from castor oil plants. Oyster mushroom spawn, produced on barley grains, was used to inoculate wet SOMW, steamed in a traditional steamer during 45 min. The mycelium growth rate on SOMW was first estimated in Petri dish by measuring the surface colonized by the mycelium. The fruit body yields were estimated on culture bags containing 2 kg each of SOMW inoculated at 7% (w/w). The local strain potential was compared with that of a commercial one. Both strains produced high-quality mushrooms, but with low yields. The supplementation of the SOMW with wheat straw at the rate of 10% and 2% of CaCO3 had significantly enhanced the productivity of the two strains, multiplying it by 3.2 for LPO and by 2.6 for CPO.
Assuntos
Agricultura/métodos , Biodegradação Ambiental , Produtos Agrícolas/metabolismo , Indústria de Processamento de Alimentos , Olea , Pleurotus/metabolismo , Eliminação de Resíduos/métodos , Agricultura/instrumentação , Argélia , Animais , Carbonato de Cálcio , Produtos Agrícolas/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Micélio/crescimento & desenvolvimento , Azeite de Oliva , Óleos de Plantas , Caules de Planta , Pleurotus/classificação , Pleurotus/crescimento & desenvolvimento , Especificidade da Espécie , TriticumRESUMO
Xerocomus chrysenteron is an edible mushroom with insecticidal properties. In an earlier work, we found that proteins are responsible for this toxicity. Here we describe the purification of a approximately 15 kDa lectin, named XCL, from the mushroom. Its cDNA and gDNA were cloned by PCR strategies and a recombinant form was expressed in Escherichia coli. Sequence alignments and sugar specificity showed that this protein is the third member of a new saline-soluble lectin family present in fungi. This protein, either purified from mushroom or expressed in vitro in E. coli, was found to be toxic to some insects, such as the dipteran Drosophila melanogaster and the hemipteran, Acyrthosiphon pisum. The lectin possesses a high insecticidal activity compared to lectin isolated from leguminosae (Lathyrus ochrus) or from the snowdrop (Galanthus nivalis).
Assuntos
Basidiomycota , Proteínas Fúngicas/isolamento & purificação , Inseticidas , Lectinas/isolamento & purificação , Sequência de Aminoácidos , Animais , Sequência de Bases , Basidiomycota/química , Basidiomycota/genética , Basidiomycota/metabolismo , Clonagem Molecular , Drosophila melanogaster , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/toxicidade , Genes Fúngicos , Lectinas/química , Lectinas/genética , Lectinas/toxicidade , Dados de Sequência Molecular , Peptídeos/genética , Peptídeos/metabolismo , Alinhamento de Sequência , Testes de ToxicidadeRESUMO
Many mushrooms are toxic to insects. To identify the chemicals involved in insecticidal activity, the toxicity of 14 species has been studied for water solubility, thermolability, and dialysis. The data strongly suggest that proteins are responsible for most of the insecticidal activity of mushroom fruitbodies and may be a source of genes available for plant protection against insects. Among proteins, lectins and hemolysins were good insecticide candidates because the toxicities were not affected by protease.
