Integrated use of residues from olive mill and winery for lipase production by solid state fermentation with Aspergillus sp

Two phase olive mill waste (TPOMW) is presently the major waste produced by the olive mill industry. This waste has potential to be used as substrate for solid state fermentation (SSF) despite of its high concentration of phenolic compounds and low nitrogen content. In this work, it is demonstrated that mixtures of TPOMW with winery wastes support the production of lipase by Aspergillus spp. By agar plate screening, Aspergillus niger MUM 03.58, Aspergillus ibericus MUM 03.49 and Aspergillus uvarum MUM 08.01 were chosen for lipase production by SSF. Plackett-Burman experimental design was employed to evaluate the effect of substrate composition and time on lipase production. The highest amounts of lipase were produced by A. ibericus on a mixture of TPOMW, urea and exhausted grape mark (EGM). Urea was found to be the most influent factor for the lipase production. Further optimization of lipase production by A. ibericus using a full factorial design (32) conducted to optimal conditions of substrate composition (0.073 g urea/g and 25% of EGM) achieving 18.67 U/g of lipolytic activity.Jose Manuel Salgado is grateful for Postdoctoral fellowship (EX-2010-0402) of Education Ministry of Spanish Government. Luis Abrunhosa was supported by the grant SFRH/BPD/43922/2008 from Fundacao para a Ciencia e Tecnologia-FCT, Portugal. Authors thank Fundacao para a Ciencia e a Tecnologia (FCT) for financial support through the project FCT Pest-OE/EQB/LA0023/2011

Diversity of streptomycetes among specific Greek terrestrial ecosystems

The diversity of streptomycetes isolated from different Greek terrestrial ecosystems using phenotypic identification, and the relationship between the number of species and the number of isolates as a diversity index, was studied. A total of 344 Streptomyces strains have been isolated and identified from diverse sites in the Greek territory, such as heavily disturbed agricultural areas and preserved forest areas, and from specific rhizosphere ecosystems. According to phenotypic identification, these strains belonged to 19 different cluster groups with a Willcox probability > 0.8. Streptomyces cyaneus, Strep. albidoflavus, Strep. diastaticus and Strep. exfoliatus were the most common cluster groups isolated from at least six different habitats. On the other hand, there were cluster groups that appeared in only one or two habitats, such as Strep. griseoflavus, Strep. rimosus, Streptoverticillium blastmyceticum, Nocardia mediterranea and Strep. fulvissimus. The diversity indices among the different cluster groups of each sampling area indicated that the different habitats can be sub-divided into two main groups: rhizosphere habitats and non-rhizosphere habitats, showing that the rhizosphere is one of the most important factors which determines the population structure of a specific soil area