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It is therefore recommended that if land requirements can be met, winery effluent should be stored in ponds prior to treatment.

Current and previous studies on bio-based (fruit) wastes and wastewaters, with a particular emphasis on research in South Africa, were reviewed. Previous studies have focused predominantly on the beneficiation and application of fruit waste as a feedstock for renewable energy. A definite gap in knowledge and application of fruit waste streams with regard to enzyme production as a value-added product is identified. The characteristics and composition of each type of fruit waste are highlighted and their potential as feedstocks in the production of value-added products is identified. The conversion of agri-industrial wastewaters to bioenergy and value-added products is discussed, with special mention of the newly published South African Bio-Economy Strategy, and the potential production of biofuels and enzymes from waste streams using recombinant Aspergillus strains. Finally, to maximise utilisation of waste streams in South Africa and abroad, a conceptual model for an integrated system using different technologies is proposed.

Aims: To assess the impact of winery wastewater (WW) on biological sand filter (BSF) bacterial community structures, and to evaluate whether BSFs can constitute alternative and valuable treatment-processes to remediate WW. Methods and Results: During 112 days, WW was used to contaminate a BSF mesocosm (length 173 cm/width 106 cm/depth 30 cm). The effect of WW on bacterial communities of four BSF microenvironments (surface/deep, inlet/ outlet) was investigated using terminal-restriction fragment length polymorphism (T-RFLP). BSF achieved high Na (95Á1%), complete Cl and almost complete chemical oxygen demand (COD) (98Á0%) and phenolic (99Á2%) removals. T-RFLP analysis combined with ANOSIM revealed that WW significantly modified the surface and deep BSF bacterial communities. Conclusions: BSF provided high COD, phenolic and salt removals throughout the experiment. WW-selected bacterial communities were thus able to tolerate and/or degrade WW, suggesting that community composition does not alter BSF performances. However, biomass increased significantly in the WWimpacted surface sediments, which could later lead to system clogging and should thus be monitored. Significance and Impact of the Study: BSFs constitute alternatives to constructed wetlands to treat agri effluents such as WW. To our knowledge, this study is the first unravelling the responses of BSF bacterial communities to contamination and suggests that WW-selected BSF communities maintained high removal performances.

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