Many phenolic compounds are essential to the regulation of electron transfer and show antioxidative activity and/or biological activity. Some of these compounds therefore give rise to unstable intermediates through oxidation, which subsequently may be converted to related natural products. The electron transter and chemical reaction of phenolic compounds via oxidation process should play important role in the evaluation of their antioxidative property and biogenesis of phenolic metabolites. The electrochemical characterization of phenolic antioxidants including the compounds isolated from Eucalyptus spp are highlighted here.

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Marine red alga Gracilaria verrucosa, a material commonly used to make agar, contains no prostaglandins(PG) in nature. But through physical stimulation, this alga was found to produce remarkable amounts of PG using enzymes and substrates in itself.
PG was produced in the amount of approximately 2g/kg in dry matter with PGE₂ at 90%. PG composition was determined mainly by polyunsaturated fatty acids present in the alga and could be controlled through use of a suitable precursor for each PG.
The data for unialgal culture of G. verrucosa confirmed that this alga produces PG. Various species of other algae belonging to the genus Gracilaria were found to produce PG in small amounts.

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This study was made to determine the mechanism for the prostaglandin (PG) synthesis in the marine alga, Gracilaria verrucosa, which is not affected by the cyclooxygenase inhibitors.
The major component of PG produced by G. verrucosa is PGE₂. To investigate PG synthesis, attention was directed to the behavior of arachidonic acid, the precursor of PGE₂.
Glycolipids and phospholipids in G. verrucosa are considered to be the stored forms of arachidonic acid, based on the results of fatty acid contents before and after the PG synthetic reaction.
Examination of the PG synthetic pathway in G. verrucosa using ¹⁴C-labeled arachidonic acid confirmed PGE₂ to be synthesized via the novel intermediate, 15-hydroperoxy-PGE₂.

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The circular dichroism (CD) of the inflammatory drug β-glycyrrhetinic acid (β-GA) with tripenoidal skelton showed considerable variation in the CD amplitude with change in solvent polarity, due primarily to the high conformational flexibility of the enone portion of the β-GA skeleton. No such variation was observed for α-GA. β-GA with a polyethylene side chain exhibited enhanced selectivity toward Li⁺ over Na⁺ or K⁺.

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Adsorption rate and adsorption isotherm of trilinolein were obtained to clarify the causes for differences in the inhibitory effects of triolein and trilinolein on β-carotene adsorption by attapulgite and sepiolite. The apparent rate of trilinolein at initial adsorption was slower than that of triolein and with no inhibitory effect. The adsorption isotherm of trilinolein could be obtained quite well by the Langmuir equation, Maximum amount of trilinolein adsorbed was proportional to the specific surface area of adsorbent, indicating one molecule of adsorbed trilinolein to occupy an area of 452Ų. The adsorption cross-sectional area of trilinolein was 1.13 times on that of triolein. The inhibitory effect of trilinolein on amount of β-carotene adsorbed was stronger than that of triolein since the cross-sectional area of trilinolein was larger than that of triolein.

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A methacrylate introduced the perfluorooctyl group was synthesised from the 2-(perfluorooctyl) ethanol and dicyclopentadiene. The monomer and 2-(perfluorooctyl) ethyl methacrylate as control were effective for copolymerzation with styrene. Each monomer reactivity ratio were r₁=1.35, r₂=0.48 and r₁=1.22, r₂=0.99 (1: styrene) respectively.
Contact angle of water on the coating sample of copolymer with styrene and cured coating sample of unsaturated polyester mixed with the monomer increased as perfluorooctyl group concentration. The former angle increased gradually with perfluorooctyl group concentration, while the latter did rapidly. It supposedly depend on localizing of perfluorooctyl group on the surface because of special properties of fluoro organic compounds.

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Study was made of 3-oxo steroids isolated from the seeds of Cannabis sativa L. The lipid fraction was chromatographed to give 5α-steroidal 3-one fraction and steroidal 4-en-3-one fraction. Examination by GC-MS indicated 24-methyl-5α-cholestan-3-one and 24-ethyl-5α-cholestan-3-one to be present in the former and 24-methylcholest-4-en-3-one and 24-ethylcholest-4-en-3-one in the latter. Campesterol and campestanol along with brassinosteroids, teasterone and castasterone were previously detected in these seeds and in the present study, 24-methyl-5α-cholestan-3-one and 24-methylcholest-4-en-3-one were found. It thus follows that the early biosynthetic reaction of brassinosteroids, campesterol →24-methylcholest-4-en-3-one→24-methyl-5α-cholestan-3-one→campestanol quite likely occurs in the seeds of C. sativa.

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