The fruit of Lonicera caerulea L. (blue honeysuckle; Caprifoliaceae) and its phenolic fraction were analyzed for nutrients and micronutrients. The phenolic fraction was prepared from berries percolated with 0.1% H3PO4 and SPE using Sepabeads SP207. The sugar and lipid content was analyzed by HPLC and GC-MS. The total content of anthocyanins was determined using the pH differential absorbance method and aliphatic acids by capillary electrophoresis. MicroLC-MS/MS was used for determination of cyanidin-3-glucoside (the predominant anthocyanin), 3,5-diglucoside, and 3-rutinoside, paeonidin-3-glucoside, 3,5-diglucoside, and 3-rutinoside, delphinidin-3-glucoside and 3-rutinoside, pelargonidin-3-glucoside, 3,5-diglucoside, and 3-rutinoside, quercetin, its 3-glucoside, and 3-rutinoside, epicatechin, protocatechuic, gentisic, ellagic, ferulic, caffeic, chlorogenic, and coumaric acids. The phenolic fraction displayed Folin-Ciocalteu reagent reducing (335 +/- 15 microg of gallic acid equivalent/mg) and DPPH and superoxide scavenging activity (IC50 12.1 +/- 0.1 and 115.5 +/- 6.4 microg/mL) and inhibited rat liver microsome peroxidation (IC50 160 +/- 20 microg/mL). The freeze-dried fruit and its phenolic fraction reduced the biofilm formation and adhesion to the artificial surface of Candida parapsilosis, Staphylococcus epidermidis, Escherichia coli, Enterococcus faecalis, and Streptococcus mutans.

Two types of sulfotransferases, namely recombinant rat liver aryl sulfotransferase AstIV and bacterial aryl sulfotransferase from Desulfitobacterium hafniense, were used for the sulfation of quercetin, its glycosylated derivatives (isoquercitrin and rutin), and dihydroquercetin ((+)‐taxifolin). The rat liver enzyme was able to sulfate only quercetin and taxifolin, whereas the quercetin glycosides remained intact. The D. hafniense enzyme sulfated isoquercitrin and rutin selectively at the C‐4′ position of the catechol moiety with very good yields. Taxifolin was sulfated at the C‐4′ position and a minor amount of the C‐3′ isomer was formed. Sulfation of quercetin proceeded preferentially at the C‐3′ position, but a lower proportion of the C‐4′ isomer was formed as well. A detailed analysis of the kinetics of this reaction is provided and a full structural analysis of all products is presented.

In nature, the flavonolignan silybin (1) occurs as a mixture of two diastereomers, silybin A and silybin B, which in a number of biological assays exhibit different activities. A library of hydrolases (lipases, esterases, and proteases) was tested for separating the silybin A and B diastereomers by selective transesterification or by stereoselective alcoholysis of 23-O-acetylsilybin (2). Novozym 435 proved to be the most suitable enzyme for the preparative production of both optically pure silybins A and B by enzymatic discrimination. Gram amounts of the optically pure substances can be produced within one week, and the new method is robust and readily scalable to tens of grams.