Phosphate → 2-(3,4-dihydroxyphenyl)-3,4-dihydro-2H-1-benzopyran-3,5,7-triol

To 0.25 mL of the resulting plasma were added 0.25 mL of a phosphate buffer (obtained by dissolving 48 g of NaH2O4, 20 g of vitamin C and 1 g of EDTA-2Na thoroughly in 1 L of distilled water and then adjusting pH of the resulting mixture to 3.9 with 0.1 mol/L NaOH) and 0.5 mL of acetonitrile, followed by thorough mixing. After addition of 3 mL of ethyl acetate and mixing, the resulting mixture was centrifuged at 3000 r/min at 4° C. for 15 minutes to obtain an upper ethyl acetate layer. The above-described extracting operation was repeated three times. The ethyl acetate layers thus obtained were collected, dried on a rotary evaporator and then dissolved in 0.9 mL of a 1:8 water-methanol mixture. The resulting solution was provided for HPLC chromatodisk. After filtration with 4.0 mL of methanol, the filtrate was dried over the rotary evaporator again. The catechin extract thus obtained (dried portion) was dissolved in 0.3 mL of a 9:1 water-acetonitrile mixture. A 0.1 mL portion of the resulting solution was provided for Chemiluminescence Analyzer (ultraweak light detector; product of Tohoku Electric Industrial Co., Ltd.) and the amount of epigallocatechin gallate (EGCg), a typical ingredient of catechins, in the plasma was measured. The catechin concentration was expressed by the amount (ng/mL) of epigallocatechin gallate per mL of plasma.

1. customobtained
2. additionmixing
3. customwere collected
4. customdried on a rotary evaporator
5. dissolutiondissolved in 0.9 mL of a 1:8 water-methanol mixture
6. customThe resulting solution was provided for HPLC chromatodisk
7. filtrationAfter filtration with 4.0 mL of methanol
8. customthe filtrate was dried over the rotary evaporator again
9. extractionThe catechin extract thus
10. customobtained
11. custom(dried portion)
12. dissolutionwas dissolved in 0.3 mL of a 9:1 water-acetonitrile mixture
13. customA 0.1 mL portion of the resulting solution was provided for Chemiluminescence Analyzer (ultraweak light detector; product of Tohoku Electric Industrial Co., Ltd.)
14. concentrationThe catechin concentration

ORD record

ord-608ee20ccfda466cae82162dff152f60

Source dataset

uspto-grants-2006_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07014876B2