Two hydroxycinnamate sucrose esters, 6'-O-(E)-feruloylsucrose and 6'-O-(E)-sinapoylsucrose, were isolated from methanol extracts of rice bran. Soluble and insoluble phenolic compounds as well as 6'-O-(E)-feruloylsucrose and 6'-O-(E)-sinapoylsucrose from white rice, brown rice, and germinated brown rice were analyzed using HPLC. The results demonstrated that the content of insoluble phenolic compounds was significantly higher than that of soluble phenolics in rice, whereas almost all compounds identified in germinated brown rice and brown rice were more abundant than those in white rice. 6'-O-(E)-Feruloylsucrose (1.09 mg/100 g of flour) and 6'-O-(E)-sinapoylsucrose (0.41 mg/100 g of flour) were found to be the major soluble phenolic compounds in brown rice. During germination, an approximately 70% decrease was observed in the content of the two hydroxycinnamate sucrose esters, whereas free phenolic acid content increased significantly; the ferulic acid content of brown rice (0.32 mg/100 g of flour) increased to 0.48 mg/100 g of flour and became the most abundant phenolic compound in germinated brown rice. The content of sinapinic acid increased to 0.21 mg/100 g of flour, which is nearly 10 times as much as that in brown rice (0.02 mg/100 g of flour). In addition, the total content of insoluble phenolic compounds increased from 18.47 mg/100 g of flour in brown rice to 24.78 mg/100 g of flour in germinated brown rice. These data suggest that appropriate germination of brown rice may be a method to improve health-related benefits.

Hawthorn polyphenol (HP) was prepared by ethyl acetate treatment of the ethanol extract (HE) of Chinese hawthorn fruit. The concentrations of 15 polyphenols in the HP, HE, extraction residue (HJ), and a hawthorn leaf extract (HF) were determined by HPLC. For HP, the total content of the 15 polyphenols was 21.4%, comprised of 19.7% of procyanidins, 1.21% of chlorogenic acid, and 0.48% of flavonoids, compared to 2.55% for the HE. The yields of procyanidin monomer, dimer, trimer, tetramer, and pentamer were 50.5%, 30.3%, 23.0%, 14.6%, and 12.5% respectively, and the mean degree of polymerization was reduced to 1.39 (HP) from 1.65 (HE). Seven different physiological actions of the four extracts were investigated. The HP showed strong O 2 À and OH scavenging capacities (IC 50 values of 6.3 g/ml and 1.1 g/ml respectively), as well as selective prolyl endopeptidase inhibition (IC 50 of 60 g/ml). The active constituents appeared to be procyanidins.Key words: Crataegus pinnatifida; HPLC; procyanidin; antioxidant; free radicalsIn Europe, standardized extracts of the leaves and flowers of Crataegus oxyacantha and Crataegus monogyna are used in the therapy for moderate (NYHA II) congestive heart failure. 1,2) These extracts exert several pharmacological and clinical effects, such as antiischemia/reperfusion-injury, anti-arrhythmic, hypolipidemic, and hypotensive effects. 1,2) Flavonoids and procyanidins are considered to be the two main active constituents. 2) Species of Chinese hawthorn, particularly Crataegus pinnatifida and Crataegus pinnatifida Bge. var. major NE Br., have also been used as herbal medicines. 2,3) Studies indicate that Chinese hawthorn extracts have beneficial effects, such as antioxidant, 4,5) anti-inflammatory, 6) and hypolipidemic effects, 7) as well as protective effects on the brain and vascular endothelium 8,9) and endothelium-dependent relaxation. 10) Recently, we analyzed 37 major cultivars of Chinese hawthorn using high performance liquid chromatography (HPLC), and found that procyanidins, which were present in high concentrations, were the main phenolic active constituents in these fruits. 11) In general, the hawthorn found in China is an edible fruit that is popular for its special acidic taste. It is bigger than its European counterpart. Since the content of organic acid in Chinese hawthorn fruits can be up to 5% (fresh weight), they are used to produce various foods, such as jams, jellies, juices, tinned foods, wines, and various sweet foods. However, the high sugar content of these fruits counteracts the benefits of polyphenols for consumers of advanced age or for those who suffer from hypertension, cardiovascular disease, or diabetes. Hence, it is desirable to separate the polyphenol and sugar components. Previously, hawthorn extract (HE) for medical applications were ethanol-extracted from the dried fruit of the Chinese hawthorn. 12) These crude extracts contain many undesirable substances, such as carbohydrates, organic acids, and moisture, which not only reduce the concentration of acti...

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