Whey Derivatives and Galactooligosaccharides Stimulate the Wound Healing and the Function of Human Keratinocytes through the NF-kB and FOXO-1 Signaling Pathways

Skin repair requires the activation of keratinocytes and is mediated by controlled inflammation and cell migration and proliferation, ending with the regeneration of well-differentiated cell layers. Whey derivatives contain galactooligosaccharides (GOS), which have potential beneficial effects on wound healing due to their activity as toll-like receptor ligands, although their direct nonprebiotic effects in the skin have not yet been described. In this study, we investigated the effects of different whey-derived products and purified GOS on a human keratinocyte cell line. We found that the inflammatory cytokine interleukin-8 (IL-8) was upregulated by nuclear factor kappa B (NF-kB) signaling triggered by whey derivatives and GOS and that wound healing was accelerated by promoting cell migration and the loss of E-cadherin in the absence of epithelial–mesenchymal transition. Interestingly, the treatments enhanced the mitochondrial function in association with the translocation of the Forkhead Box O1 (FOXO-1) transcription factor. Finally, we detected the increased expression of the differentiation markers induced by GOS and whey derivatives. All together, our results show that GOS-containing products can promote wound closure and skin health by direct activity on keratinocyte functions. Among the preparations tested, the fermented compound produced by autochthonous microorganisms was the most active in modulating keratinocyte activity, supporting the biological value of whey derivatives for health

The effects of temperature and pH on the extraction of oxalate and pectin from green kiwifruit ( Actinidia deliciosa

Oxalates and pectin were extracted from four locally grown fruits at three different pH levels, 6.9, 0.6 and - 0.3, at two different temperatures, 21 and 80°C. Green kiwifruit (Actinidia deliciosa L. Hayward), golden kiwifruit (Actinidia chinensis L. Hort 16A Zespri), kiwiberry (Actinidia arguta, CV. Takaka Green) and persimmon (Diospyros kaki) contained moderate levels of oxalates. Total and soluble oxalates were more efficiently extracted at 21°C using 2 M HCL, while the highest amounts of pectin were extracted from the fruits at 80°C using 0.2 M HCL. Extraction using 0.2 and 2 M HCL gave the highest yields of total oxalates, which ranged from 47.1 to 220.4 mg total oxalates per 100 g dry matter (DM) for persimmon and kiwiberry, respectively. Extraction using water at 21°C gave soluble oxalate contents ranging from 21.2 mg 100 g⁻¹ DM, for persimmon, to 105.0 mg 100⁻¹ DM, for kiwiberry fruits. Extraction of pectin was not achieved efficiently using water at either temperature, while extraction using 2 M HCL gave lower values; optimal extractions of pectin were achieved at 80°C using 0.2 M HCL