Studies On Functional Activity Of Pickled Greening Garlic And Separation And Properties Of The Green Pigments

Vinegar pickled garlic is a kind of traditional food which is said in folk to have some pharmaceutical effects, but there has been no scientific reports about its function. On the other hand, Large quantites of green pigments are formed when garlic is pickled in vinegar or crushed into purees. The pigments are proved to be nontoxic, so it is feasible to develop them as natural colorants.In this paper, nutritional composition and functions of vinegar-pickled garlic were studied, and exploratory research is carried out in isolation and properties of the green pigments. The main results of this paper are as follows.Compared with fresh garlic, the content of protein, Lipids, soluble carbohydrate, ash, Vitamin C and Vitamin B₁ in pickled garlic decreased. The major components of the pickle juice were soluble carbohydrates, polypeptides (MW<3000Da) and ash. The total contents of protein, lipids, ash in pickled garlic and the juice kept invariable, total soluble carbohydrates increased, and Vitamin C decreased greatly. In pickled garlic, the ratio of total essential amino acids and protein increased, and AAS values of most essential amino acids increased. The increase of Cysteine and Alanine indicated that there may be some metabolic or chemical reactions happened.In all the three assays, the extracts of pickled garlic and the juice exhibited good antioxidant activity. In DPPH assay and inhibition of lipid peroxidation, the activity order of the extracts was: ethanol extract>pickle juice>aqueous extract. In ESR assay, all extracts exhibited stronger activities of attenuating the production of hydroxyl radical than that of superoxide. In scavenging hydroxyl radical, the activity order was the same as in the other two assays. While in scavenging superoxide, aqueous extract was the most effective one, the activity order was aqueous extract >pickle juice> ethanol extract. The antioxidant activity of the extracts was lower than fresh garlic comparison.The effect of pickled garlic extracts on tumor cell growth was examined. For HL-60 human leucocythemia cell and gastric cancer cell BGC-823, the inhibitory activity order of the extracts was: ether extract > ethanol extract>pickle juice>aqueous extract, the picked garlic extracts were more effective than fresh garlic comparison. For MDA-MB-435 breast cancer cell, water-soluble components exhibited good activity, the activity order was: pickle juice>aqueous extract >ether extract > ethanol extract. For Bel-7402 liver cancer cell and PC-3M-1E8 prostate cancer cell, only ether extract and ethanol extract exhibited inhibitory effect.The ethanol extracts of pickled garlic and the pickle juice exhibited good antimicrobial activity for the strains tested. The antimicrobial activity order was: ethanol extract>pickle juice>aqueous extract. The activity of the aqueous extract of pickled garlic was much lower than that of fresh garlic. A method for isolation and fractionation of the coloring material from greening garlic was devised based on chromatography using Amberlite CG-50, SIPI-40 resin, silicon gel, and Sephadex LH-20 gel column. The green pigments were proved to be composed of two fractions: the blue pigments and the yellow pigments.Characteristics and stability of the two pigments were also studied. The visible A max-values of the two partially purified pigments were 592nm(blue) and 440nm (yellow), respectively. Both were polarsubstance and soluble in water, methanol, ethanol and n-butenol. The pigments kept stable at acid pH values while faded quickly at pH>7.The effect of light, heating, ascorbic acid, oxidant and reductant enhanced the decomposition of the two pigments while most of the metal ions used (except Fe3+) had little effect on the pigments. The radical scavenging activities of the two pigments extracts were examined using DPPH and ESR assays and both showed antioxidant activity.Microcapsules of the two pigments were prepared. The processing condition was as follows: optimum composition of maltdextrin and Arab gum 16:4, B-cyclodextrinl.5%, pigment content4%, and total soli...