Anthocyanins were isolated from 19 kinds of vegetables and fruits. Individual anthocyanins were analyzed by HPLC using a photodiode array detector and were examined for the heating and ultraviolet irradiation stabilities of these anthocyanins. This report deals with the relationship between anthocyanin composition and heating or ultraviolet irradiation stabilities of anthocyanins. Stable anthocyanins showed many anthocyanin peaks and a high ratio of acylated anthocyanin peaks. This result shows that the anthocyanin composition and the rate of acylation affect the stability of anthocyanins.

We have bred red-fleshed potato from hybrid seedlings between cultivars of Solanum tuberosum ssp. tuberosum and S. tuberosum ssp. andigena. The anthocyanin of red-fleshed potato inactivated both influenza viruses A (IVA) and B (IVB). The IC 50 of red-fleshed potato anthocyanin was 48 g/ml (IVA) and 54 g/ml (IVB). The IC 50 of pelanin was 107 g/ml (IVA) and 83 g/ml (IVB). The antiviral activities of pelanin against influenza viruses were lower than the red-fleshed potato anthocyanin. In our previous reports black currant anthocyanins showed an additive antiviral effect. Therefore, we believe that the antiviral activity of the potato anthocyanin comes from the additive or synergistic effect of each anthocyanin pigments and other coexisting pigments.

Anthocyanin pigments (AN) were extracted and purified from sweet potatoes (Ipomoea batatas Poir.) of Ayamurasaki, Yamagawamurasaki, Kankei-55, Tanegashimamurasaki, Y-617, Y-637, Beniazuma (skin) and Beniimo, and examined yields, spectrum characteristics, composition ratios and' stabilities.(1) A positive correlation was observed between Emaxs of the extracts and yields of ANs provided from various sweet potatoes, and the yield of Ayamurasaki AN was the highest in the eight sweet potatoes.(2) Structures of Ayamurasaki ANs were estimated as 3-caffeoylsophoroside-5-glucosides, 3-caffeoylcaffeoylsophoroside-5-glucosides, 3-caffeoyl-p-hydroxybenzoylsophoroside-5-glucosides, and 3-caffeoylferuloylsophoroside-5-glucosides of cyanidin and peonidin by LC/MS. (3) ANs of Ayamurasaki and Yamagawamurasaki were peonidin type ANs, and Kankei-55, Tanegashimamurasaki, Y-617, Y-637 and Beniimo ANs were cyanidin type ANs. ANs in skin of' Beniazuma were different at the kind and the composition ratio from ANs inner part of the tuberous root. (4) Sweet potato ANs were stabler than the pigments of red cabbage, shiso, strawberry and apple for heating, ultraviolet rays irradiation either. Major ANs of Ayamurasaki decreased in heating and ultraviolet rays irradiation either. New ANs were detected when irradiated with ultraviolet rays.

Anthocyanin pigments (AN) extracted and purified from purple sweet potatoes (Yamagawamurasaki and Kankei 55) were studied for stability during alcoholic fermentation. The fermentation was continued for 7 days, followed by aging up to day 120. Analyses were performed to measure pH, sugar and alcohol contents, browning, relative absorbance at 525 nm, and hue, individual AN and alcohol by high-performance liquid chromatography (HPLC). Up to day 7 of fermentation: 1) pH decreased slightly; 2) browning increased; 3) absorbance increased; 4) the hue of Yamagawa

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