JPH0355518B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an antioxidant whose main component is an extract from tea leaves, and more specifically to a composition in which the antioxidant properties of an extract from tea leaves are enhanced. Therefore, it can be used in a wide range of fields such as foods, cosmetics, and pharmaceuticals. [Prior Art] Tea leaves contain large amounts of multiple polyphenol compounds collectively called tannins, and it is well known that these compounds are generally water-soluble and exhibit strong reducing or antioxidant effects. It is known [Journal of the Japan Food Industry Association, Vol. 10, No. 1, pp. 1-5 (1963)]. Furthermore, among these components, catechins have a synergistic effect with caffeine [Journal of the Japan Food Industry Association Vol. It was also known that they have a synergistic effect [Journal of the Japanese Society of Agricultural Chemistry, Vol. 59, No. 2, pp. 129-134 (1985)]. [Problems to be solved by the invention] As mentioned above, certain synergistic effects among catechins were known, but nothing was known about the interactions of tea leaf extract itself with various compounds. . [Means for Solving the Problems] In order to put into practical use the components that have antioxidant effects present in tea leaf components as described above, the present inventors have proposed to further enhance the effects of the antioxidant components. As a result of intensive research, the present invention was completed after discovering that the antioxidant effect of the components in tea leaves can be significantly enhanced by adding a certain type of acid. That is, the present invention provides a tea leaf antioxidant composition characterized in that one or more aliphatic hydroxycarboxylic acids are added to a tea leaf extract. The unrefined tea leaf extract, which is the main component of the present invention, can be obtained by conventional methods such as methanol, ethanol,
Extracted with a water-soluble organic solvent such as acetone, water, or a mixed solvent thereof from which fat-soluble components have been removed can be used without particular limitation. As the aliphatic hydroxycarboxylic acid used in the present invention, saturated aliphatic hydroxy polycarboxylic acids are preferred, and citric acid, malic acid, tartaric acid, etc. are particularly preferred. The appropriate amount of aliphatic hydroxycarboxylic acid to be added is about 0.1 to 20 by weight per 1 part tea leaf extract; too little will result in a weak effect, and too much will not produce the desired effect. does not appear. The antioxidant composition of the present invention may be mixed into the target product as a mixed powder depending on the shape of the target product, or it may be used as a solution by dissolving it in a suitable solvent such as ethanol or hydroalcohol. Alternatively, it can be used as an emulsion. [Example] Next, the present invention will be explained in more detail with reference to Reference Examples and Examples, but the present invention is not limited thereto. Reference example: Add methanol 90 to 30 kg of Kuzucha, a by-product of sencha production, and extract by heating at about 60℃ for about 3 hours, filter, wash the remaining solids with methanol 30, and make about 90 methanol extract. I got it. Add and mix 1.5 kg of Daizu oil and 6.0 kg of water to this extract, and after distilling methanol off at a vacuum level of 80 mmHg, bath temperature of 60°C, and cooling water temperature of 10°C, separate the liquid phase into 5.0 kg of oil phase and 10.5 kg of water phase. Got Kg. The aqueous phase was concentrated at a vacuum level of 20 mmHg, a bath temperature of 70°C, and a cooling water temperature of 10°C until the solid content reached approximately 80%, and then transferred to another container.
It was vacuum dried at 0.5 mmHg and a shelf temperature of 60°C for about 18 hours.
By pulverizing the obtained solid matter, 4.5 kg of powder of water-soluble antioxidant components of tea leaf extract was obtained. The catechin purity in this powder was about 47%, and the caffeine content was about 8%. The main sugar components were fructose, glucose, and sucrose, and the total amount was about 10%. The ultraviolet absorption spectrum of the water-soluble antioxidant component obtained according to this reference example is shown in FIG. λ
(max) = 272 nm, E (1%, 1 cm) = 177.3. A liquid chromatogram is also shown in FIG.
The conditions for this chromatography are as follows. Column: ODS 5μ, 4.6Φ×250mm Mobile phase: Acetonitrile: Water = 1:4 Flow rate: 0.6ml/min Pressure: 110-120Kg/cm ² Detector: UV275nm (0.16ABU) Chart speed: 2.5mm/min Sample: 0.1% aqueous solution Injection fee: 5μ The identification of the compound in the peak is as follows. A: Unknown substance B: (-) Epigallocatechin C: (-) Epigallocatechin gallate D: Caffeine E: (-) Epicatechin gallate Example Antioxidant property against ethyl linoleate (peroxide value (meq/Kg) ) Place 2 g of ethyl linoleate (>90% (GC), manufactured by Tokyo Kasei Co., Ltd.) in a glass bottle with a height of 35 mm, an inner diameter of 15 mm, and a capacity of 5 ml, and add 0.05 - of each antioxidant solution dissolved in ethyl alcohol to this. Add 0.1 ml (according to the amount shown in the table), mix well, and leave at 63°C ± 1°C for 16 hours without sealing. Weigh out approximately 1g of this accurately into a stoppered Erlenmeyer flask (200ml),
Solvent (chloroform: glacial acetic acid = 2:3 (v/v))
Add 25ml, stopper, and shake gently to mix. Next, add 1 ml of saturated potassium iodide aqueous solution, cap, and mix gently for 1 minute. 75ml after leaving it in the dark at room temperature for 5 minutes
of water and titrate with N/100 Na ₂ S ₂ O ₃ solution while stirring. The end point was based on the iodostarch reaction. Peroxide value (meq/Kg) = N/100Na ₂ S ₂ O ₃ (ml) x f x 10/weighed ethyl linoleate (g) f: N/100Na ₂ S ₂ O ₃ normality coefficient of solution The antioxidant activity against ethyl linoleate of the tea leaf extract obtained in Reference Example and various antioxidants obtained by adding an aliphatic hydroxycarboxylic acid to the tea leaf extract is expressed in terms of peroxide value. For comparison, the antioxidant activities of D(+) catechin and caffein against ethyl linoleate are also shown.

[Table] The effect of adding aliphatic hydroxycarboxylic acid to tea leaf extract is superior to that of D(+) catechin. For comparison, we also confirmed the synergistic effect of caffeine with D(+) catechin in the literature, but it was not clear. [Effects of the Invention] The composition of the present invention, in which an aliphatic hydroxycarboxylic acid is added to a tea leaf extract, has higher effects than a mixture of pure catechins, which are antioxidant components contained in tea leaf components, and the acid. also exhibits stronger antioxidant activity.

[Brief explanation of drawings]

FIG. 1 is an ultraviolet absorption spectrum of a water-soluble antioxidant component obtained from tea leaves according to a reference example of the present invention, and FIG. 2 is a liquid chromatogram thereof.

Claims (1)

[Scope of Claims] 1. A tea leaf antioxidant composition characterized in that one or more aliphatic hydroxycarboxylic acids are added to an unrefined tea leaf extract. 2. The tea leaf antioxidant composition according to claim 1, wherein the aliphatic hydroxycarboxylic acid is a saturated hydroxy polycarboxylic acid. 3. The tea leaf antioxidant composition according to claim 1, wherein the aliphatic hydroxycarboxylic acid is one or more selected from citric acid, malic acid, and tartaric acid. 4. The tea leaf antioxidant composition according to claim 1, wherein the amount of aliphatic hydroxycarboxylic acid added is about 0.1 to 20 by weight relative to the tea leaf extract.