- Physicochemical, antimicrobial, and cytotoxic characteristics of a chitosan film cross-linked by a naturally occurring cross-linking agent, aglycone geniposidic acid
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The purpose of this study was to evaluate the characteristics of a chitosan film cross-linked by a naturally occurring compound, aglycone geniposidic acid (aGSA). This newly developed aGSA-cross-linked chitosan film may be used as an edible film. The chitosan film without cross-linking (fresh) and the glutaraldehyde-cross-linked chitosan film were used as controls. The characteristics of test chitosan films evaluated were their degree of cross-linking, swelling ratio, mechanical properties, water vapor permeability, antimicrobial capability, cytotoxicity, and enzymatic degradability. It was found that cross-linking of chitosan films by aGSA (at a concentration up to 0.8 mM) significantly increased its ultimate tensile strength but reduced its strain at fracture and swelling ratio. There was no significant difference in the antimicrobial capability between the cross-linked chitosan films and their fresh counterpart. However, the aGSA-cross-linked chitosan film had a lower cytotoxicity, a slower degradation rate, and a relatively lower water vapor permeability as compared to the glutaraldehyde-cross-linked film. These results suggested that the aGSA-cross-linked chitosan film may be a promising material as an edible film.
- Mi, Fwu-Long,Huang, Chin-Tsung,Liang, Hsiang-Fa,Chen, Mei-Chin,Chiu, Ya-Ling,Chen, Chun-Hung,Sung, Hsing-Wen
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- Studies on the blue pigments produced from genipin and methylamine. II. On the formation mechanisms of brownish-red intermediates leading to the blue pigment formation
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The mechanisms of the formation of brownish-red pigments having a 2-methyl-4-carbomethoxy-2-pyrindine nucleus as a basic skeleton by reaction of genipin with methylamine under an atmosphere of inert gas are discussed based on the isolation of 5,6-dihydro-2-methyl-4-carbomethoxy-8-hydroxymethyl-2-pyrindine as a precursor and on comparisons of the results obtained from the reactions of genipin congeners and methylamine. The origin of the extra methyl group at C-6 in the structures of some of the brownish-red pigments was clarified to be the carbon atom of the hydroxymethyl group at C-8 of genipin by using deuterium-labelled genipin.
- Touyama,Inoue,Takeda,Yatsuzuka,Ikumoto,Moritome,Shingu,Yokoi,Inouye
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- Synthesis and biological evaluation of geniposide derivatives as potent and selective PTPlB inhibitors
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Herein a series of Geniposide derivatives were designed, synthesized and evaluated as protein tyrosine phosphatase 1B (PTPlB) inhibitors. Most of these compounds exhibited potent in vitro PTP1B inhibitory activities, the representative 7a and 17f were found to be the most potent inhibitors against the enzyme with IC50 values of 0.35 and 0.41 μM, respectively. More importantly, they showcased 4 to10-fold selectivity over SHP2 and 3-fold over TCPTP. Further biological activity studies revealed that compounds 7a, 17b and 17f could effectively enhance insulin-stimulated glucose uptake with no significant cytotoxicity. Subsequent molecular docking and structural activity relationship analyses demonstrated that the glucose scaffold, benzylated glycosyl groups, and arylethenesulfonic acid ester significantly impact on the activity and selectivity.
- Lei, Shuwen,Zhang, Dongdong,Qi, Yunyue,Chowdhury, Sharmin Reza,Sun, Ran,Wang, Juntao,Du, Yi,Fu, Lei,Jiang, Faqin
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- Pentacetylgardenoside cyclohexanamide capable of reducing uric acid activity and preparation method and application of pentacetylgardenoside cyclohexanamide
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The invention belongs to the technical field of drug synthesis, and particularly relates to pentacetylgardenoside cyclohexanamide capable of reducing uric acid activity and a preparation method and application of the pentacetylgardenoside cyclohexanamide.
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Paragraph 0020
(2019/11/21)
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- The method of manufacturing a red dye and red dye bioactivation
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PROBLEM TO BE SOLVED: To provide a manufacturing method for a red pigment having improved color tone. SOLUTION: The method for manufacturing the red pigment includes a step for reacting an iridoid compound having a carboxyl group at 4-position of an iridoid skeleton with an amino acid or a protein hydrolysate and a step for adding a compound for producing a sulfite ion to the reaction product. COPYRIGHT: (C)2012,JPO&INPIT
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Paragraph 0053
(2016/12/26)
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- Asymmetric total synthesis of the iridoid β-glucoside (+)-geniposide via phosphine organocatalysis
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Phosphine-catalyzed [3 + 2] cycloaddition of ethyl-2, 3-butadienoate with enone (S)-3b occurs with high levels of regio- and stereocontrol to deliver the c/s-fused cyclopenta[c]pyran 4 characteristic of the iridoid family of natural products. Cycloadduct 4 was converted to the iridoid glycoside (+)-geniposide in 10 steps.
- Jones, Regan A.,Krische, Michael J.
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supporting information; experimental part
p. 1849 - 1851
(2009/09/06)
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- New alkaloids from Daphniphyllum calycinum
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Four new alkaloids, 17-hydroxyhomodaphniphyllic acid (1), daphcalycinosidine C (2, a new iridoid alkaloid), yuzurimine E (3), and yuzurimic acid B (4), were isolated from the seeds of Daphniphyllum calycinum. The structures of these Daphniphyllum alkaloids were determined by spectroscopic analysis including mass spectrometry and 2D NMR.
- El Bitar, Hoda,Nguyen, Van Hung,Gramain, Anthony,Sevenet, Thierry,Bodo, Bernard
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p. 1094 - 1099
(2007/10/03)
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- Hair dyeing by iridoid glycosides and aglycons thereof
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A method of dyeing hair which comprises contacting hair with an iridoid glycoside or an aglycon thereof.
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- Red coloring composite and the method for its production
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PCT No. PCT/JP78/00054 PCT Filed Dec. 14, 1978 Sec. 371 Date Aug. 9, 1979 Sec. 102(e) Date Aug. 9, 1979 PCT Pub. No. WO79/00394 PCT Pub. Date Jul. 12, 1979. Novel reddish coloring compounds of varying hue and the method for its production, obtained by reaction between iridoid compounds contained in biological substances, where if necessary, by pretreatment with chemical or enzymic means to form --COOH at the C-4 position, and in the case of glycosides by hydrolysis of iridoid compounds to aglycones with chemical or microbial or enzymic means, and a substance possessing a primary amino group under acidic condition.
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