Plant-associated Fungi: Methods for Taxonomy, Diversity, and Bioactive Secondary Metabolite Bioprospecting.

Plants harbor a large reservoir of fungal diversity, encompassing endophytic, epiphytic, phytopathogenic, and rhizosphere-associated fungi. Despite this diversity, relatively few fungal species have been characterized as sources of bioactive secondary metabolites. The role of secondary metabolites is still not fully understood; however, it is suggested that these metabolites play important roles in defense mechanisms and fungal interactions with other organisms. Hence, fungal secondary metabolites have potential biotechnological applications as prototype molecules for the development of therapeutic drugs. In this chapter, we describe the main methods used for routine fungi isolation, production of crude fungal extracts, and chemical characterization of bioactive compounds. In addition, explicative notes about the steps described are provided to explore the diversity of the endophytic, phytopathogenic, epiphytic, and rhizosphere fungi and to evaluate the biotechnological potential of each group.

Evaluation of a Combined System Based on an Upflow Anaerobic Sludge Blanket Reactor (UASB) and Shallow Polishing Pond (SPP) for Textile Effluent Treatment

Abstract Color removal from textile effluents was evaluated using a laboratory-combined process based on an upflow anaerobic sludge blanket (UASB) reactor followed by a shallow polishing pond (SPP). The anaerobic reactor was fed with a real textile effluent, diluted 10-times in a 350 mg/L solution of pre-treated residual yeast extract from a brewery industry as nutrient source. The parameters color, COD, N-NH3 and toxicity were monitored throughout 45 days of operation. According to the results, decolorization and COD removal were highest in the anaerobic step, whereas the effluent was polished in the SPP unit. The overall efficiency of the complete UASB-SPP system for COD and color were 88 and 62%, respectively. Moreover, the N-NH3 generated by the residual yeast extract ammonification was below 5 mg/L for the final effluent. Finally, no toxicity was detected after the treatment steps, as shown by the Vibrio fischeri microscale assay.

Anaerobic-Aerobic Combined System for the Biological Treatment of Azo Dye Solution using Residual Yeast.

This study aimed to investigate the treatment efficiency of a synthetic dye solution in an anaerobic-aerobic combined reactor system, using pretreated residual yeast as a nutrient source and redox mediator. The applicability of the residual yeast as a nutrient source was firstly evaluated in anaerobic batch tests. Subsequently, two continuous bench-scale treatment settings were studied: (1) an Upflow Anaerobic Sludge Blanket (UASB) reactor followed by an activated sludge system and, (2) a UASB reactor followed by a shallow polishing pond. The two system configurations were fed with a synthetic azo dye solution of Yellow Gold Remazol (50 mg/L) and pretreated residual yeast (350 mg/L). According to the results, the UASB/shallow polishing pond-combined reactor attained the best values of chemical oxygen demand (COD) (85%) and dye removal (23%).