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Epimedium is widely used in traditional Chinese medicine and contains rich bioactive compounds. These compounds often have a methyl group at their 4'-OH position catalyzed by methyltransferases. Therefore, studying methyltransferases in Epimedium plants is of great significance. In this study, a flavonol methyltransferase, EpOMT4, was isolated from Epimedium pseudowushanense B.L. Guo. The recombinant enzyme regiospecifically transferred a methyl group to the 4'-OH position of 8-prenylkaempferol forming icaritin. The study demonstrates that enzymatic methylation of flavonoids in Epimedium plants holds significant potential and could provide a promising alternative method for the biosynthetic production of bioactive methylated prenylflavonoids.

Short-chain dehydrogenase/reductases (SDRs) belong to the NAD(P)(H)-dependent oxidoreductase superfamily, which have various functions of catalyzing oxidation/reduction reactions and have been generally used as powerful biocatalysts in the production of pharmaceuticals. In this study, ScSDR1 and ScSDR2, two new SDRs have been identified and characterized from Stachybotrys chartarum 3.5365. Substrate scope investigation revealed that both of the enzymes possessed the ability to oxidize β -OH to ketone specifically, and exhibited substrate promiscuity and high stereo-selectivity for efficiently catalyzing the structurally different prochiral ketones to chiral alcohols. These findings not only suggest that ScSDR1 and ScSDR2 might be potent synthetic tools in drug research and development, but also provide good examples for further engineered enzymes with higher efficiency and stereo-selectivity.

Anhydroicaritin ( 1a ), baohuoside ( 1b ) and icariin ( 1c ) were recognized as major pharmacologically active ingredients of Epimedium plants. Their primary means of acquisition were chemical isolation from plants. However, it suffers from low yield, environmental pollution and shortage of plants. Herein, to remedy these problems, biosynthesis was explored to obtain the three active ingredients. Fortunately, with SfFPT as 8-prenyltransferase, EpPF3RT and Ep7GT as glycosyltransferases, kaempferide ( 1 ) was transferred to 1a , 1b and 1c enzymatically. Thus, we report the details of this method. This approach represents a promising environmental friendly alternative for the production of these compounds from an abundant analogue.

In this work, a novel isophorone-based fluorescent probe H-1 was designed and synthesized. The probe H-1 could achieve highly selective detection of Al 3+ through forming a 1:1 complex, with a recognition mechanism based on intramolecular charge transfer (ICT). The detection limit of the probe H-1 for Al 3+ is as low as 8.25 × 10 -8 M which was determined by fluorescent titration. It is confirmed that H-1 could be used not only for fluorescence spectrometry to detect Al 3+ ions in actual water samples, but also for biological imaging to detect Al 3+ ions in cells and plants., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Peridecalins C and D ( 1 and 2 ), one decalin and one oxygen-decalin containing polyketide-amino acid hybrids with 5/6/6 ring system, was isolated from a genetic mutant of Periconia sp. F-31. Their structures were elucidated through extensive spectroscopic data analysis, including 1 D/2D NMR and HR-MS spectra. Biosynthetically, two proposed Diels-Alder reactions are supposed to be involved in the skeleton construction of 1 and 2 .

One new eremophilane sesquiterpene periconianone L ( 1 ), together with four known guaiane-type sesquiterpenes 4,10,11-trihydroxyguaiane ( 2 ), (-)-guai-1(10)-ene-4 α ,11-diolhydroxymecuration ( 3 ), guaidiol A ( 4 ), and epi-guaidiol A ( 5 ) were isolated from the endophytic fungus Periconia sp. F-31. The structure of the new compound was established by spectroscopic methods, including UV, IR, HRESIMS, and extensive NMR techniques. Compound 3 was isolated as natural product for the first time.