Formation of ethyl ferulate from feruloylated oligosaccharide by transesterification of rice koji enzyme under sake mash conditions

Approaches for the enzymatic synthesis of alkyl hydroxycinnamates and applications thereof

Alkyl hydroxycinnamates (AHs) is a group of molecules of biotechnological interest due to their cosmetic, food, and pharmaceutical applications. Among their most interesting uses are as UV protectants, skin depigmentation agents, and antioxidant ingredients which are often claimed for their antitumoral potential. Nowadays, many sustainable enzymatic approaches using low-cost starting materials are available and interesting immobilization techniques are helping to increase the reuse of the biocatalysts, allowing the intensification of the processes and increasing AHs accessibility. Here a convenient summary of AHs most interesting biological activities and possible applications is presented. A deeper analysis of the art state to obtain AHs, focusing on most employed enzymatic synthesis approaches, their sustainability, acyl donors relevance, and most interesting enzyme immobilization strategies is provided.Key points• Most interesting alkyl hydroxycinnamates applications are summarized.• Enzymatic approaches to obtain alkyl hydroxycinnamates are critically discussed.• Outlook of enzyme immobilization strategies to attain alkyl hydroxycinnamates.

Four new sesquiterpenoids with anti-inflammatory activity from the stems of Jasminum officinale

Four new sesquiterpenoids，including three nor-cinalbicane type sesquiterpenoids, named Jasminol A, G, H (1-3) and one eremophilene-type sesquiterpenoid, named Jasminol B (4) together with nine known compounds (5-13) were isolated from the stems of Jasminum officinale L. The structures of new compound were elucidated on the base of IR, HR-ESI-MS, 1D NMR, 2D NMR and DEPT analysis, and the absolute configurations were determined by single-crystal X-ray diffraction analysis. In addition, the anti-inflammatory activity of isolated compounds was evaluated using lipopolysaccharide (LPS)-induced murine macrophage RAW264.7, and compounds 1-4 exhibited a moderate inhibition of LPS-induced nitric oxide (NO) production in RAW264.7 cells with IC₅₀ values of 20.56 ± 1.31, 30.12 ± 0.89, 30.35 ± 2.72 and 31.60 ± 1.69 μM, respectively, and CC₅₀ values >200 uM.

Rice used for Japanese sake making

Sake is a Japanese traditional alcoholic beverage made from rice and water. Recently, its export and its production in countries other than Japan have increased. In accordance, both the breeding and the cultivation of sake rice varieties have been extended to wide areas of Japan. To breed new sake rice cultivars and to cultivate rice with high suitability for sake production, an understanding of the properties of the ingredient rice grains and the factors affecting sake making is important. The influence of various rice properties, such as starch structure, protein, water absorption, and grain polishing, on sake making are being revealed in detail. In this review, the properties of rice used for sake making are summarized in terms of fermentation science and rice cultivation.

Quantitation and sensory properties of three newly identified pyroglutamyl oligopeptides in sake

Three new peptides: (pGlu)L-ethyl, (pGlu)LFGP-ethyl and (pGlu)LFNP-ethyl, were identified in the search for pyroglutamyl oligopeptide ethyl esters in sake. The ethyl esterified peptides in sake were quantitated using stable isotope dilution analysis and additional quantitation of (pGlu)L was performed using an external standard method. The concentrations of (pGlu)L-ethyl and (pGlu)L in 33 commercial sake samples ranged from 0.16 to 1.57 mg/L and 1.49 to 7.55 mg/L, respectively. The sensory properties of the pyroglutamyl oligopeptide ethyl esters and corresponding non-esterified peptides were examined: the estimated difference threshold of (pGlu)L (2.0 mg/L) and (pGlu)L-ethyl (0.267 mg/L) was exceeded in 32 and 26 samples, respectively. Estimated thresholds of (pGlu)LFGP-ethyl and (pGlu)LFNP-ethyl were often lower than the levels in quantitated sake samples. The sensory effects of these pyroglutamyl dipeptides on a model sake quality may be negative because of their unpleasant taste, however, (pGlu)LFNP-ethyl may be positive because of its mild taste.