Enzymatic upcycling of wild-simulated ginseng leaves for enhancing biological activities and compound K.

Compound K (CK), a ginsenoside with high bioavailability, is present at low levels in wild-simulated ginseng leaves (WSGL). WSGL contains the CK precursors, Rd and F2, in amounts up to 26.4 ± 0.4 and 24.1 ± 1.9 mg/g extract, respectively. In this study, CK production in WGSL reached 25.9 ± 1.0 mg/g extract following treatment with Viscozyme, Celluclast 1.5 L, Pectinex Ultra SP-L, and their combination. The antioxidant activities indicated by oxygen radical absorbance capacity, ferric reducing antioxidant power, and ABTS- and DPPH radical scavenging activity of enzyme-treated WSGL were enhanced 1.69-, 2.51-, 2.88-, and 1.80-fold, respectively, compared to non-treated WSGL. Furthermore, the CK-enriched WSGL demonstrated a 1.94-fold decrease in SA-ß-galactosidase expression in human dermal fibroblasts and a 3.8-fold enhancement of inhibition of nitric oxide release in lipopolysaccharide-induced RAW 264.7 cells relative to non-treated WSGL. Consequently, WSGL subjected to enzymatic upcycling has potential as a functional material in the food and pharmaceutical industries.

Immobilized Candida antarctica lipase B as an sn-1,3 regiospecific biocatalyst for the interesterification of triacylglycerols with fatty acid ethyl esters.

Candida antarctica lipase B (CALB) is regarded as non-regiospecific. This study aimed to investigate the regiospecificity of CALB in the solvent-free interesterification of high-oleic sunflower oil with stearic acid ethyl ester for 1,3-distearoyl-2-oleoylglycerol (SOS)-rich fat preparation using a packed bed reactor. The content ratio of 1,2-distearoyl-3-oleoylglycerol (SSO) to SOS (denoted by SSO/SOS content) obtained using Lipozyme 435 (a commercially immobilized CALB; 0-4.1%), at residence times (1-32 min) was similar to that obtained using Lipozyme RM IM (0-3.0%), but lower than that obtained using Lipozyme TL IM (6.0-39.4%). When immobilized on Lewatit VP OC 1600, Lipozyme CALB had an SSO/SOS content of 0-10.4%, which was greater than that of Palatase 20,000 L (0-1.1%) but was lower than that of Lipozyme TL 100 L (8.8-97.7%). Our findings suggest that immobilized CALB shows distinct sn-1,3 regiospecificity in the interesterification of triacylglycerol with fatty acid ethyl esters.

Enhancement of the bioactive compounds and biological activities of maca (Lepidium meyenii) via solid-state fermentation with Rhizopus oligosporus.

Maca (Lepidium meyenii Walp) is renowned for its phytochemicals, including amino acids, saponins, and macamides, confer nutritional and medicinal benefits. This study analyzed the bioactive constituents of maca via solid-state fermentation with Rhizopus oligosporus for 0-15 days. After fermentation, the l-carnitine content reached 157.3 µg/g. A 93% increase in macamide B was recorded after 7-day fermentation. Total flavonoid and saponin contents increased by 88.2% and 110.3%, respectively. The fermentation process significantly enhanced the physicochemical attributes of maca; in particular, its water retention and cholesterol-binding capacities increased by 1.73- and 4.30-fold, respectively, compared with the non-fermented maca. Moreover, fermented maca exhibited stronger antioxidant and α-glucosidase-inhibiting effects than non-fermented maca. Finally, the neuroprotective effect of maca on HT-22 cells increased by 23% after 5-day fermentation. These findings demonstrate the potential of fermented maca as a novel ingredient for foods, beverages, and pharmaceuticals. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01508-6.

α-Alkylation and Asymmetric Transfer Hydrogenation of Tetralone via Hydrogen Borrowing and Dynamic Kinetic Resolution Strategy Using a Single Iridium(III) Complex.

Here we present a novel strategy for the synthesis of enantiomerically enriched tetrahydronaphthalen-1-ols. The reaction proceeds via an alkylation (via hydrogen borrowing) and ammonium formate-mediated asymmetric transfer hydrogenation (via dynamic kinetic resolution), giving alkylated tetralols in high yields and good enantio- and diastereoselectivity across a diverse range of both alcohol and tetralone substrates. Additionally, these products were successfully derivatized to several complex molecules, demonstrating the utility of the tetrahydronaphthalen-1-ol.