• Natural Product Sciences
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• v.21 no.4
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• pp.293-296
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• 2015

A new L-isoascorbic acid derivative epi-leptosphaerin (1) and two known compounds leptosphaerin (2), and verongamine (3) were isolated from sponges of the orders Verongida and Thorectidae. Compounds 1 and 2 are most likely of sponge-associated fungal origin. In the present study, isolated compounds were investigated for their inhibition of soluble epoxide hydrolase (sEH), which is considered a promising target for the management of pain, inflammation, and comorbidities associated with diabetes. Compound 3, verongamine, displayed weak inhibitory activity against sEH with an $IC_{50}$ value $51.5{\pm}1.0{\mu}M$.

• Journal of the Korean Chemical Society
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• v.35 no.3
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• pp.253-257
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• 1991

The optically active glycerol acetonides are often used as important chiral intermediates for many syntheses. In connection with the development of inhibitors of phospholipases, we have compared the synthetic routes to (S)-and (R)-glycerol acetonide from D-mannitol and D-isoascorbic acid, and L-serine and L-ascorbic acid, respectively. In our hands, the conversions of L-serine to (R)-glycerol acetonide and of D-mannitol to (S)-glycerol acetonide were found to be most effective.

• Korean Journal of Microbiology
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• v.26 no.4
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• pp.324-331
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• 1988

Ascorbate oxidizing enzyme from the crude extract of Pleurotus ostreatus was purified by ammonium sulfate precipitation, preparative polyacrylamide gel electrophoresis, DEAE Sepharose CL-6B ion exchange chromatography and Sephadex G-150 gel filtration chromatography. The molecular weight of the enzyme estimated by Sephadex G-150 gel filtration chromatography was 140,000 and that of its subunit by SDS-polyacrylamide gel electrophoresis 66,000. The optimum pH for the maximum activity of the enzyme was 5.2 and the isoelectric point of the enzyme was 6.0 Km values for L-ascorbic acid and D-isoascorbic acid were both 2.2.$\mu$M, which indicates that the enzyme has the asme affinity towards both substrates.