Fermented Brown Sugar Residue Prolongs the Caenorhabditis elegans Lifespan via DAF-16

Purification of biomass ethanol from the products of brown sugar yeast-fermentation produces a large amount of residue. This fermentation residue contains abundant brown sugar-derived nutrients and is mainly used as compost or livestock feed. However, the in vivo physiological effects of oral residue ingestion are not known. The purpose of this study was to elucidate the physiological action and molecular mechanism of fermented brown sugar residue in nematode stress tolerance, aging, and lifespan using Caenorhabditis elegans. Fermented brown sugar residue was divided into two layers, supernatant and precipitate, and each was given to nematodes. Analysis of motility and survival rate under thermal stress revealed reduced mobility and increased survival rate following treatment with fermented brown sugar residue. The survival rate of nematodes under 1% H2O2 was markedly increased by the residue and mitochondrial membrane depolarization was induced and mitochondrial radical oxygen species levels increased. Furthermore, aging dependent reduction of motility was suppressed, and the average life span of nematodes was extended by treatment with fermented brown sugar residue. Moreover, the effects of fermented brown sugar residue on stress tolerance, lifespan elongation, and decreased aging dependent momentum reduction were lost in the daf-16 mutant. Taken together, our results show that the various physiological actions of fermented brown sugar residue, including stress tolerance and lifespan extension, occur via DAF-16.