Wastes from the agro-industrial sector, due to their toxic effects with regard to plants and living organisms, cannot be dumped in the soil. However, they can serve as renewable source of value-added products, following the specific digestive treatment. This research was focused on studies of vinasse fermentation processes in the presence of bioactive substances introduced directly into the digested biomass. The results obtained testify that the substances of natural origin used as additives, demonstrate the pronounced effects on alcoholic fermentation of vinasse under the mesophilic conditions. The comparative assessment of different additives action in the studied processes have demonstrated that the dihydroxyfumaric acid caused the emission of 266 cm3 CO2 in 76 hours, aescinum – 251 cm3 in 55 hours, tomatin – 233 cm3 during 78 hours, sclareol – 232 cm3 during 55 hours, vanillin – 229 cm3 during 69 hours, whereas catechin – 180 cm3 during 61 hours of fermentation, until the fermentation process was completed. Thus, the study of the effects of bioactive substances with possible antioxidant properties on biomass from winemaking sector with identification of these processes mechanisms can be a perspective direction, suggesting the new ways of wastes valorisation.

The article contains a review of methods and procedures of the municipal wastewater treatment, with the discussion of their specifics. A new concept is proposed related to the selection of municipal sewerage and wastewater treatment systems, considering the local/decentralized, semicentralized or centralized systems, especially those suitable to rural and suburban localities, in dependence on the advantages and disadvantages of these systems and local specifics. The concept of phytofilters is proposed for the biological treatment of wastewater in small towns. This technology is simple, inexpensive and requires relatively little maintenance. Biological ponds in the Republic of Moldova have proven to be very suitable for advanced wastewater treatment, being a cheap and natural purification system with a good potential for implementation. When choosing a sewer system, priority must be given to its functionality and practical considerations.