Adding sorbitol improves the thermostability of α-l-rhamnosidase from Aspergillus niger and increases the conversion of hesperidin

α-L-rhamnosidase: production, properties, and applications

α-L-rhamnosidase [EC 3.2.1.40] belongs to glycoside hydrolase (GH) families (GH13, GH78, and GH106 families) in the carbohydrate-active enzymes (CAZy) database, which specifically hydrolyzes the non-reducing end of α-L-rhamnose. Αccording to the sites of catalytic hydrolysis, α-L-rhamnosidase can be divided into α-1, 2-rhamnosidase, α-1, 3-rhamnosidase, α-1, 4-rhamnosidase and α-1, 6-rhamnosidase. α-L-rhamnosidase is an important enzyme for various biotechnological applications, especially in food, beverage, and pharmaceutical industries. α-L-rhamnosidase has a wide range of sources and is commonly found in animals, plants, and microorganisms, and its microbial source includes a variety of bacteria, molds and yeasts (such as Lactobacillus sp., Aspergillus sp., Pichia angusta and Saccharomyces cerevisiae). In recent years, a series of advances have been achieved in various aspects of α-validates the above-described-rhamnosidase research. A number of α-L-rhamnosidases have been successfully recombinant expressed in prokaryotic systems as well as eukaryotic systems which involve Pichia pastoris, Saccharomyces cerevisiae and Aspergillus niger, and the catalytic properties of the recombinant enzymes have been improved by enzyme modification techniques. In this review, the sources and production methods, general and catalytic properties and biotechnological applications of α-L-rhamnosidase in different fields are summarized and discussed, concluding with the directions for further in-depth research on α-L-rhamnosidase.

Hesperetin as an anti-SARS-CoV-2 agent can inhibit COVID-19-associated cancer progression by suppressing intracellular signaling pathways

Hesperetin, an aglycone metabolite of hesperidin with high bioavailability, recently gained attention due to its anti-COVID-19 and anti-cancer properties. Multiple studies revealed that cancer patients are prone to experience a severe form of COVID-19 and higher mortality risk. In addition, studies suggested that COVID-19 can potentially lead to cancer progression through multiple mechanisms. This study proposes that hesperetin not only can be used as an anti-COVID-19 agent but also can reduce the risk of multiple cancer progression by suppressing several intracellular signaling pathways in cancer patients with COVID-19. Therefore, in this review, we attempted to provide evidence demonstrating anti-COVID-19/cancer properties of hesperetin with several mechanisms.