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There have been many studies on the secondary metabolites of fruiting bodies of Basidiomycetes,2) but only a few on the prevention of skin pigmentation. 3. 4) It has been reported that such tyrosinase inhibitors as kojic acid, hydroquinone and hinokitiol were effective against skin pigmentation. 5 ,6) In our screening of new tyrosinase inhibitors among fungal metabolites, we have found that the lipophilic fractions of Albaterellus confluens, Sarcodon scabrosus, Rojites lilacea, Lyophil/um aggregatum, and Ramaria botrytis has tyrosinase inhibitory activity. This paper describes the isolation and characterization of the active principles of Albatrellus confluens. An ethanol extract of A. confluens was partitioned between water and ethyl acetate. The ethyl acetate extract was separated by silica gel column chromtography and HPLC. Each fraction was examined for the tyrosinase inhibitory activity. Two active principles, compounds 1 and 2, were isolated. Compound 1, C 22 H 32 0 2 , showed the presence of four allylic methyls, one benzylic methyl, three olefinic methines, four allylic methy1enes, one doubly allylic methylene signal, and two meta-coupled aromatic protons in the 1H-NMR spectrum. Its 13C-NMR spectrum contained 22 peaks. In the mass spectrum of 1, the fragmentation peaks were very similar to those of neogrifolin. These facts indicated that compound 1 was neogrifolin, and this was confirmed by a direct comparison with literature data. 7 • 8) Compound 2, C 22 H 32 0 2 , showed mass spectral peaks agreeing with those of grifolin. The 1H-NMR and 13C-NMR data are shown in the experimental section, and all data for 2 agreed with those of grifolin. 7 • 8) These two compounds were isomers with respect to the position of substituents on the aromatic ring. The farnesyl group is located in the 4-position with neogrifolin and in the 2-position with grifolin. The tyrosinase inhibitory activity of compounds 1 and 2 was assayed according to the method of Shimao et al. 9) Both compounds 1 and 2 inhibited tyrosinase activity, the 50% inhibitory dose (ID so) appearing at 2511M for compound 1. This value is approximately equivalent to that of kojic acid. On the other hand, the ID 50 value for compound 2 was 760I1M. It is very interesting that the position of the farnesyl group on the aromatic ring affects the tyrosinase inhibitory activity.

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Effects of various ingredients on the texture of lemon jellies prepared from gellan gum, citric acid and sweetener were investigated by rheological measurement and sensory evaluation. The data were analyzed by use of the modification of Scheffé's mixture experiment method in converse triangle experiment area. The contours of the response surface were drawn using the best model whose terms were searched by AIC statistic, and the approximate model was calculated to consider the contours. “Hardness” estimated by both methods was large in jellies with high content of gellan gum and low content of citric acid. The content of citric acid significantly influenced “smoothness” estimated by a subjective method. The influence of citric acid varied with the content of gellan gum. The correlation coefficients of evaluation between “hardness” and “lemon flavor” or “sourness” were negative.

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