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Biology subjects

Contreras, R. A.

Publications and source records attributed to Contreras, R. A..

2 recordsLinked to original sources

Priming of C-glycoside flavones in Colobanthus quitensis with salicylic acid, methyl jasmonate, pimelic acid, suberic acid, and azelaic acid elicits antifungal activity against Botrytis cinerea

Colobanthus quitensis, one of only two native angiosperms in Antarctica, produces C-glycosyl flavones with antifungal activity against Botrytis cinerea. In this study, the exogenous application of the elicitors salicylic acid (SA), methyl jasmonate (MeJA), pimelic acid (PA), suberic acid (SuA), and azelaic acid (AzA) was evaluated for their effect on the accumulation of bioactive metabolites in in vitro-cultivated plants. Exposure to these compounds significantly modulated the expression of key genes in the phenylpropanoid and flavonoid pathways, including pal, chs, chi, fnsII, as well as regulatory genes such as myb12, bhlh, and wrky33, enhancing PAL activity and the accumulation of schaftoside, neoschaftoside, saponarin, and swertiajaponin. This priming process improved the antifungal activity of the extracts, with MeJA and PA identified as the most effective treatments. The in vitro culture approach enabled the assessment of a protected and hard-to-access species without the need for wild harvesting. These results suggest that the exogenous application of elicitors constitutes an efficient strategy to modulate the biosynthesis of specialised metabolites, with implications for the development of biocontrol agents and the improvement of efficiency in sustainable agricultural systems. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=88 SRC="FIGDIR/small/646165v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@67f8corg.highwire.dtl.DTLVardef@9ff3a1org.highwire.dtl.DTLVardef@13403aaorg.highwire.dtl.DTLVardef@1dc95b2_HPS_FORMAT_FIGEXP M_FIG C_FIG

plant biology↗

Inhibition of Myoglobin Oxidation by Food Grade Botanical Antioxidant Formulations

This study explores the antioxidant capabilities of green tea and acerola extracts in inhibiting myoglobin oxidation, a critical factor in preserving color stability in food products, mainly plant-based meat analogs. Extracts were analyzed for their antioxidant activity using DPPH and ORAC assays, followed by evaluations of their inhibitory effects on myoglobin oxidation at 25 {degrees}C and 35 {degrees}C. Acerola showed quick inhibitory effects even at lower concentrations and moderate temperatures, likely due to its high ascorbic acid levels. On the other hand, green teas effectiveness varied with temperature, with inhibition rates rising at 35 {degrees}C, probably because its polyphenolic compounds are sensitive to heat. The kinetics and thermodynamics analysis showed positive activation energy (Ea) for green tea, meaning it becomes more active as temperatures rise. In contrast, acerolas negative Ea indicates heat reduces its efficacy. These results suggest that acerola and green tea could be natural alternatives to synthetic antioxidants, helping preserve the appearance and stability of different food products.

biochemistry↗