Association of preharvest management with oxidative protection and enzymatic browning in minimally processed cassava

The aim of this study was to examine oxidative protection and enzymatic browning in the storage of minimally processed cassava and their relationship with population density and harvest age. Population densities were 1.0, 1.25, 1.5, and 1.75 plants m^-2 . After being harvested at 300, 360, or 420 days after planting, cassava were minimally processed and stored at 5 ± 2°C. It was observed that superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) play key roles in the tolerance of young roots to browning. Planting density, however, does not appear to be a key factor modulating the activity of the enzymes studied. PRACTICAL APPLICATIONS: Younger harvested cassava roots, harvested at 300 days, are more tolerant to enzymatic browning. This appears to be in part due to enzymatic activity modulation of the SOD, CAT, and POD enzymes. In addition, it has been demonstrated that agronomic techniques aimed at increasing productivity, such as increasing the planting density of cassava, do not alter the biomarkers of postharvest quality. In summary, evidence that field management may be an efficient approach to improving the conservation of minimally processed cassava is provided. We believe that the findings of this paper will be of great interest regarding the influence of field management on the postharvest quality of freshly cut cassava and will also provide applicable results relating to its production chain.

Enhancement of Cell Adhesion, Cell Growth, Wound Healing, and Oxidative Protection by Gelatins Extracted from Extrusion-Pretreated Tilapia (Oreochromis sp.) Fish Scale

Gelatin has been broadly utilized in the food, pharmaceutical, photographic, cosmetic and packaging industries, and there is also huge potential for novel applications of gelatin in the fields of biotechnology and biomedicine. In the present study, we extracted gelatin from fish processing waste, i.e., scale of tilapia, by a combined method of extrusion-pretreatment and hot water extraction. The extrusion-pretreatment process increases the extraction yield of gelatin. Three gelatins (FS2: preconditioning with double-distilled water (ddH₂O) before extrusion; FS12: preconditioning with citric acid solution before extrusion; FS14: preconditioning with acetic acid solution before extrusion) were obtained and all of them enhanced cell adhesion, cell growth, and wound healing in HaCaT cells and protected HaCaT cells from H₂O₂-induced cellular damage. Among FS2, FS12, and FS14, FS12 exhibited the most pronounced enhancement of cell adhesion, cell growth, and wound healing in HaCaT cells, and thus it may have potential as an effective natural raw material in cell therapies for cutaneous wounds and for reducing H₂O₂-induced oxidative damage of cells. In additional experiments, it was found that phosphorylations of Akt and mTOR are involved in the signaling pathway activated by FS2, FS12, and FS14 in HaCaT cells.