Preparation Of Thearubigins Pigment And Its Biological Activity

Tea pigment, as a kind of natural pigments, is a kind of water-soluble pigments mixtureoxidative polymerization derived mainly by catechin of P-diphenol compound from the tea,according to colour can divide three categories, includes theaflavins (TFs), thearubigins (TRs),theabrownins (TBs). Modern pharmacology study showes that tea pigment has strongantioxidant and scavenge free radicals function, so it has potential development value in foodand medical fields, this value has caught people’s attention already.This paper studies the tea polyphenols chemical oxidation and tea microorganismfermentation producing Thearubigins, and optimizes the best conditions for the latter of theextraction process; According to the different mechanism, and with four kinds of methods todetermine the preparation of tea red element class pigment antioxidant activity. The resultswere as follows:1. Tea polyphenols alkaline oxidation preparation theabrownins for the best optimaloxidation conditions: choose KOH/H2O lye system and alkali concentration of1mol/L;optimum temperature for50℃, and best reaction time for30min; tea polyphenolsconcentration by2%. Theabrownins solution acidification preparation thearubigins for thebest conditions: acidification pH is4.5; Under normal temperature acidification and notconsider acidification time when aciding treatment thoroughly incorporated.2. With vine tea as raw material fermentation for theabrownins preparation of theoptimal conditions: the optimal strains fxk-01; fermentation temperature30℃; fermentationtime10days; Inoculation amount of5%. The complete fermentation of vine tea’sTheabrownins content improves3.62times than not fermentation. The complete fermentationof Theabrownins for the optimum extraction conditions: extraction temperature of100℃;extraction time20min; extraction times for three times; Material liquid than1to30.3. With pu’er tea as raw material fermentation for Theabrownins preparation of theoptimal conditions: the optimal strains fxk-02; fermentation temperature35℃; fermentationtime7days; Inoculation amount of5%. The complete fermentation of pu’er tea’sTheabrownins content improves8.23times than not fermentation. The complete fermentationof Theabrownins for the optimum extraction conditions: extraction temperature for80℃; extracting time35min; extraction times for twice; Material liquid than1to30.4. Fermentation methods obtained Theabrownins (TB’) have very strong antioxidantactivity, the antioxidant activity than Vc, and chemical methods obtained Theabrownins (TB)have the slightly strong antioxidant activity, the antioxidant activity slightly below the Vc,Meanwhile, chemical acidification methods obtained Thearubigins (TR) have strongantioxidant activity, the antioxidant activity than Vc, and fermentation acidification methodsobtained Thearubigins (TR ‘) have the slightly strong antioxidant activity, the antioxidantactivity below Vc.