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1.
Heliyon ; 8(8): e10284, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36051263

ABSTRACT

Background: Endothelial dysfunction is an early pathophysiological feature and independent predictor of a poor prognosis in most forms of cardiovascular disease. We evaluated the effect of brown rice crackers (BR-C) on endothelial function. Methods: Effect of heat-moisture treated (HMT) -BR-C on postprandial flow-mediated dilation (FMD) in adults with mild endothelial dysfunction was compared with that of BR-C and white rice crackers (WR-C) in 12 adults with mild endothelial dysfunction (less than 7.0% of FMD) by a randomized, single-blind, three-treatment three-period crossover trial (UMIN 000034898). Since we considered that the FMD increase was associated with the treatment of HMT-BR-C, we examined the effect of three possible factors: postprandial glucose levels, polyphenol content, and polyphenol release from the food matrix. Results: Mean pre-intake baseline FMD values of HMT-BR-C, BR-C, and WR-C were 4.9%, 5.1%, and 4.9%, respectively, and those values 1 h post-intake were 6.3%, 5.1%, and 4.8%, respectively. There was no difference in intergroup comparisons of FMD using Dunnett's multiple comparison test. There was a significant increase in FMD only in HMT-BR-C in intragroup comparisons (P = 0.042 by paired-t test). In comparison with BR-C, no significant difference was noted in the postprandial glucose level nor in the content of total polyphenols and ferulic acid derivatives in HMT-BR-C. However, the 70% ethanol extracted from HMT-BR-C contained a significantly larger amount of free and bound ferulic acids than from BR-C. Conclusion: HMT-BR-C intake increased the postprandial FMD response.

2.
Foods ; 11(6)2022 Mar 12.
Article in English | MEDLINE | ID: mdl-35327240

ABSTRACT

As it has been reported that type 2 diabetes mellitus increases the risk of Alzheimer's disease, we investigated how to prevent type 2 diabetes and dementia using biofunctional boiled rice. We adopted unpolished super-hard rice (SHBR) for diabetes and wax-free unpolished black rice (WFBBR) for dementia and blended those with ordinary non-polished rice (KBR) (blending ratio 4:4:2), adding 2.5% waxy black rice bran (WBB) and 0.3% rice oil after high-pressure treatment (HPT) (WFBSK) to improve its palatability. This boiled rice is rich in dietary fiber, anthocyanin, free ferulic acid and ß-secretase inhibitory activity. A randomized, parallel-group comparison study was conducted for 12 weeks with 24 subjects, using Cognitrax to evaluate their cognitive function primarily. Furthermore, as the secondary purpose, we performed a single-dose test for postprandial blood glucose and insulin secretion at the end of the human intervention test. After 12 weeks, consumers of the WFBSK rice exhibited significant improvement in language memory by cognitive test battery compared with those who consumed the control white rice (p < 0.05). Moreover, subjects who consumed the WFBSK rice had lower insulin secretion levels than those who consumed the control polished rice (p < 0.05).

3.
J Fungi (Basel) ; 7(9)2021 Sep 21.
Article in English | MEDLINE | ID: mdl-34575820

ABSTRACT

Reportedly, the intake of koji amazake, a beverage made from steamed rice fermented by Aspergillus oryzae, improves defecation frequency. However, its functional ingredients and mechanism of action remain unclear. To compare the effects of koji amazake and a placebo beverage on defecation frequency and to identify the functional ingredients and mechanism of action, a randomized, placebo-controlled, double-blind parallel-group comparative trial was performed on two groups. The koji amazake had 302 ± 15.5 mg/118 g of A. oryzae cells, which was not in the placebo. Compared with the placebo group, the koji amazake group showed a significant increase in weekly defecation frequency at 2 weeks (5.09 days vs. 4.14 days), 3 weeks (5.41 days vs. 4.18 days), and 4 weeks (5.09 days vs. 3.95 days), along with an increase in the weekly fecal weight at 4 weeks (724 g vs. 501 g). The intake of koji amazake did not induce significant intergroup differences in the fecal SCFA concentration, whereas it significantly decreased the relative abundance of Blautia and significantly increased that of Bacteroides at 3 weeks. Therefore, koji amazake intake improved defecation frequency, and A. oryzae cells played potentially important roles as functional ingredients.

4.
Biosci Biotechnol Biochem ; 84(2): 365-371, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31690219

ABSTRACT

Rice with double mutation of starch synthase IIIa and branching enzyme IIb (ss3a/be2b) has much higher amounts of apparent amylose and resistant starch (RS) than usual varieties. In this study, we conducted two randomized, single-blind, crossover trials to investigate the effect of single ingestion of two processed foods composed of ss3a/be2b mutant rice on postprandial blood glucose and insulin response in healthy adults, compared to those of usual cultivar. In trial 1, of ingestion of rice crackers, the incremental area under the curves of glucose (IAUCglc) and insulin (IAUCins) in RS group was significantly lower than in the control group. In trial 2, of the ingestion of cooked rice, IAUCglc in the RS group was significantly lower than in the control group. These results showed that the ss3a/be2b-mutant rice cracker and cooked rice having high RS can attenuate postprandial blood glucose and insulin response.


Subject(s)
Blood Glucose/analysis , Insulin/blood , Oryza , Postprandial Period , Starch , Adult , Cooking , Cross-Over Studies , Female , Humans , Male , Middle Aged , Nutritive Value , Single-Blind Method , Young Adult
5.
J Sci Food Agric ; 96(11): 3717-22, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26676315

ABSTRACT

BACKGROUND: Metabolic syndrome is a major risk factor for a variety of obesity-related diseases. Recently, the effects of functional foods have been investigated on lipid metabolism as a means to reduce lipid content in the blood, liver and adipose tissues associated with carnitine O-palmitoyltransferase (CPT) activity. Acanthopanax senticosus (Rupr. et Maxim) Harms (AS) is a medicinal herb possessing a wide spectra of functions including antioxidant, anti-inflammatory and anti-fatigue actions. Despite much research being focused on the cortical roots of AS, little information is available regarding its leaves, which are also expected to promote human health, for example by improving abnormal lipid metabolism. Here, we explored whether AS leaves affect lipid metabolism in mice fed a high-fat diet. RESULTS: The administration of AS to BALB/c mice fed a high-fat diet significantly decreased plasma triglycerides (TG). CPT activity in the liver of these mice was significantly enhanced by AS treatment. CONCLUSION: These findings indicate that AS leaves have the potential to alleviate increase in plasma TG levels due to high-fat diet intake in mice, possibly by increasing mitochondrial fatty acid ß-oxidation, especially via CPT activation. Consequently, daily intake of AS leaves could promote beneficial health effects including the prevention of metabolic syndrome. © 2015 Society of Chemical Industry.


Subject(s)
Diet, High-Fat , Eleutherococcus , Hyperlipidemias/metabolism , Hypolipidemic Agents/pharmacology , Liver/drug effects , Plant Extracts/pharmacology , Triglycerides/blood , Animals , Carnitine O-Palmitoyltransferase/metabolism , Hyperlipidemias/blood , Hyperlipidemias/etiology , Hyperlipidemias/prevention & control , Hypolipidemic Agents/therapeutic use , Lipid Metabolism , Liver/metabolism , Male , Mice, Inbred BALB C , Mitochondria/metabolism , Phytotherapy , Plant Extracts/therapeutic use , Plant Leaves
6.
J Nutr Sci Vitaminol (Tokyo) ; 60(1): 43-51, 2014.
Article in English | MEDLINE | ID: mdl-24759259

ABSTRACT

The effects of acute or chronic intake of boysenberry juice or artificial vinegar on blood pressure (BP) and endothelial function were investigated in spontaneous hypertensive rats (SHR). A single administration of boysenberry juice (BJ, equivalent to 0.5 mL/kg body weight) or artificial boysenberry juice vinegar (BJV, equivalent to 0.5 mL BJ and 0.10 g acetic acid/kg body weight) decreased both systolic blood pressure (SBP) and diastolic blood pressure (DBP) significantly. Reductions in SBP of the control group compared with the BJ and BJV groups reached maxima of -16.8±4.3 and -28.4±7.3 mmHg 8 h after administration, respectively. Chronic SBP- and DBP-lowering effects were also observed upon daily feedings of both BJ and BJV at 4 wk. No significant differences were found in SBP or DBP between respective acute and chronic intake of BJ and BJV, except for the decrease in DBP after 4 wk of BJV intake. This suggests that the polyphenol constituents in BJ and BJV likely play a major role in lowering SBP and DBP under these conditions and that acetic acid added to BJ exerts a DBP-lowering effect after 4 wk of BJV intake. The polyphenolic constituents of these beverages might elevate plasma NO concentration via aortic endothelial nitric oxide synthase activation, but the effects of chronic intake on blood pressure might also be at least partly mediated by the renin-angiotensin system. These results may help explain the beneficial effects of boysenberry intake on cardiovascular health, such as reduced blood pressure and improved endothelial function.


Subject(s)
Beverages/analysis , Blood Pressure/drug effects , Fruit/chemistry , Animals , Male , Nitric Oxide/blood , Nitric Oxide Synthase Type III/metabolism , Plant Extracts/administration & dosage , Polyphenols/administration & dosage , Rats , Rats, Inbred SHR , Renin-Angiotensin System/drug effects
7.
Int J Food Sci Nutr ; 64(8): 988-92, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23848379

ABSTRACT

There is an increasing interest in dietary polyphenols for risk reduction in cardiovascular diseases. The aim of this study was to evaluate acute and chronic flow-mediated dilation (FMD) and blood pressure responses to daily intake of boysenberry juice. FMD of the brachial artery was measured in six subjects in the initial, intermediate and follow-up stages of a 4-week open-label intervention study. The intake of boysenberry juice (180 ml/d) increased FMD with progression of intervention stage, and FMD differed in the follow-up stage compared with pre-intake baseline (p = 0.0163 < 0.0167 = 0.1/6) using Bonferroni correction. Changes in systolic blood pressure (SBP) correlated negatively with SBP before intake only in the follow-up stage (r = -0.961 and p = 0.0007 at 3.5 h), indicating a greater SBP reduction in subjects with higher SBP. These results suggest that daily intake of boysenberry juice is beneficial for reducing cardiovascular risk.


Subject(s)
Blood Pressure/drug effects , Cardiovascular Diseases/prevention & control , Fruit/chemistry , Hypertension/diet therapy , Polyphenols/pharmacology , Rosaceae/chemistry , Vasodilation/drug effects , Adult , Aged , Beverages , Blood Pressure/physiology , Brachial Artery , Cardiovascular Diseases/etiology , Cardiovascular Diseases/physiopathology , Dilatation, Pathologic , Female , Humans , Hypertension/physiopathology , Male , Middle Aged , Phytotherapy , Plant Preparations/pharmacology , Risk Factors
8.
Foods ; 2(4): 462-477, 2013 Oct 14.
Article in English | MEDLINE | ID: mdl-28239130

ABSTRACT

Cocoa beans contain many functional ingredients such as theobromine and polyphenols, but also contain a relatively high amount of caffeine, which can negatively impact human health. It is therefore desirable to reduce caffeine levels in cocoa powder used to make chocolate or cocoa beverages while retaining functional ingredients. We have established conditions for supercritical carbon dioxide (SCCO2) extraction that remove 80.1% of the caffeine from cocoa powder while retaining theobromine (94.1%) and polyphenols (84.7%). The antioxidant activity of the decaffeinated cocoa powder (DCP) made with this optimized SCCO2 extraction method was 85.3% that of non-processed cocoa powder. The total procyanidin and total polyphenol concentrations of the DCPs resulting from various SCCO2 extractions showed a significant positive correlation with oxygen radical absorbance capacity (ORAC). The correlation coefficient between total polyphenols and ORAC was higher than that between total procyanidins and ORAC; thus, the concentration of total polyphenols might be a greater factor in the antioxidant activity of DCP. These results indicate that we could remove large quantities of caffeine from conventional high-cocoa products while retaining the functional benefits of high polyphenol content. This SCCO2 extraction method is expected to be applicable high-cocoa products, such as dark chocolate.

9.
Biosci Biotechnol Biochem ; 76(9): 1694-701, 2012.
Article in English | MEDLINE | ID: mdl-22972352

ABSTRACT

The antihypertensive effect of a single oral administration of a boysenberry seed polyphenol extract to spontaneously hypertensive rats was evaluated at different doses (100 and 200 mg/kg), and a significant decrease in systolic blood pressure (SBP) was observed up to 6 h post administration. The extract was separated into proanthocyanidin-rich and ellagitannin fractions by solvent partition. A significant decrease in SBP was observed only after administering the proanthocyanidin-rich fraction, and this decrease was abolished by an N(G)-nitro-L-arginine methyl ester (L-NAME) injection. An analysis of the orally absorbable components showed that intact dimeric and trimeric procyanidins and propelargonidins were detectable in the plasma with a maximal concentration 2 h post administration. The vasorelaxant activity of the extract was also confirmed by in vitro assay using rat aorta rings. These results suggest that proanthocyanidins (PAs) in boysenberry seeds may have played an important role in the observed antihypertensive effect.


Subject(s)
Antihypertensive Agents/isolation & purification , Hypertension/drug therapy , Proanthocyanidins/isolation & purification , Rosaceae/chemistry , Seeds/chemistry , Vasodilator Agents/isolation & purification , Absorption , Administration, Oral , Animals , Antihypertensive Agents/administration & dosage , Aorta/drug effects , Blood Pressure/drug effects , Hypertension/metabolism , Hypertension/physiopathology , Male , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/metabolism , Plant Extracts/chemistry , Proanthocyanidins/administration & dosage , Rats , Rats, Inbred SHR , Tissue Culture Techniques , Vasodilator Agents/administration & dosage
10.
J Biosci Bioeng ; 113(6): 788-91, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22382011

ABSTRACT

Using microplates as pressure and cultivation vessels, a high-throughput method was developed for analyzing the high-pressure inactivation kinetics of microorganisms. The loss of viability from a high-pressure treatment, measured based on the growth delay during microplate cultivation, showed reproducibility with the conventional agar plate method and was applicable for the kinetics analysis.


Subject(s)
Disinfection/methods , Microbial Viability , Pressure , Kinetics , Reproducibility of Results
11.
Biosci Biotechnol Biochem ; 75(8): 1435-9, 2011.
Article in English | MEDLINE | ID: mdl-21821959

ABSTRACT

The antihypertensive and vasorelaxant effects of water-soluble proanthocyanidins, extracted in persimmon leaf tea, were investigated in spontaneously hypertensive rats, rat aortas, and human umbilical vein endothelial cells. Oral administration of proanthocyanidins significantly decreased the systolic blood pressure of the rats after 4 h, as compared with distilled water controls. A vasorelaxant effect on rat aortas was induced by proanthocyanidins, and it was abolished by removal of the endothelium and inhibition of endothelial nitric oxide synthase and soluble guanylyl cyclase activity. The phosphorylation levels of endothelial nitric oxide synthase (Ser-1177) and the upstream kinase Akt (Ser-473) in umbilical cells also increased in a time-dependent manner after the addition of a proanthocyanidin-rich fraction. These results suggest that the antihypertensive effect of proanthocyanidins in persimmon leaf tea is due to vasorelaxation via an endothelium-dependent nitric oxide/cGMP pathway, and that proanthocyanidins might be useful in dietary lowering of blood pressure.


Subject(s)
Antihypertensive Agents/pharmacology , Blood Pressure/drug effects , Diospyros/chemistry , Endothelium, Vascular/metabolism , Hypertension/metabolism , Phytotherapy , Plant Extracts/pharmacology , Proanthocyanidins/pharmacology , Vasodilator Agents/pharmacology , Administration, Oral , Animals , Antihypertensive Agents/chemistry , Aorta/drug effects , Aorta/physiopathology , Cyclic GMP/metabolism , Endothelium, Vascular/cytology , Endothelium, Vascular/drug effects , Human Umbilical Vein Endothelial Cells , Humans , Hypertension/drug therapy , Hypertension/physiopathology , Male , Nitric Oxide/metabolism , Nitric Oxide Synthase Type III/metabolism , Phosphorylation/drug effects , Plant Extracts/chemistry , Plant Leaves/chemistry , Proanthocyanidins/chemistry , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Inbred SHR , Solubility , Tea/chemistry , Vasodilator Agents/chemistry
12.
Biochem Biophys Res Commun ; 410(3): 608-13, 2011 Jul 08.
Article in English | MEDLINE | ID: mdl-21684256

ABSTRACT

Mouse embryonic stem cells (ESCs) can be induced to form pancreatic exocrine enzyme-producing cells in vitro in a stepwise fashion that recapitulates the development in vivo. However, there is no protocol for the differentiation of pancreatic-like cells from human ESCs (hESCs). Based upon the mouse ESC model, we have induced the in vitro formation of pancreatic exocrine enzyme-producing cells from hESCs. The protocol took place in four stages. In Stage 1, embryoid bodies (EBs) were formed from dissociated hESCs and then treated with the growth factor activin A, which promoted the expression of Foxa2 and Sox17 mRNAs, markers of definitive endoderm. In Stage 2, the cells were treated with all-trans retinoic acid which promoted the transition to cells that expressed gut tube endoderm mRNA marker HNF1b. In Stage 3, the cells were treated with fibroblast growth factor 7 (FGF7), which induced expression of Pdx1 typical of pancreatic progenitor cells. In Stage 4, treatment with FGF7, glucagon-like peptide 1, and nicotinamide induced the expression amylase (AMY) mRNA, a marker for mature pancreatic exocrine cells. Immunohistochemical staining showed the expression of AMY protein at the edges of cell clusters. These cells also expressed other exocrine secretory proteins including elastase, carboxypeptidase A, chymotrypsin, and pancreatic lipase in culture. Production of these hESC-derived pancreatic enzyme-producing cells represents a critical step in the study of pancreatic organogenesis and in the development of a renewable source of human pancreatic-like exocrine cells.


Subject(s)
Cell Culture Techniques , Cell Differentiation , Embryoid Bodies/cytology , Pancreas, Exocrine/cytology , Activins/pharmacology , Amylases/biosynthesis , Carboxypeptidases A/biosynthesis , Chymotrypsin/biosynthesis , Embryoid Bodies/drug effects , Embryoid Bodies/enzymology , Embryonic Stem Cells/cytology , Embryonic Stem Cells/drug effects , Embryonic Stem Cells/enzymology , Fibroblast Growth Factor 7/pharmacology , Glucagon-Like Peptide 1/pharmacology , Hepatocyte Nuclear Factor 3-beta/biosynthesis , Humans , Lipase/biosynthesis , Niacinamide/pharmacology , Pancreas, Exocrine/enzymology , Pancreatic Elastase/biosynthesis , SOXF Transcription Factors/biosynthesis , Tretinoin/pharmacology
13.
Biosci Biotechnol Biochem ; 75(4): 650-5, 2011.
Article in English | MEDLINE | ID: mdl-21512242

ABSTRACT

Persimmon leaf (PL) has been commonly recognized for its wide variety of health benefits. A previous study has reported that persimmon leaf extract (PLE) contained flavonols with the 2″-galloly moiety (PLEg). Galloylated homologues generically show stronger activity in their biological function, so enhanced functions can be expected for PLEg. We investigated in this present study the effect of PLEg on the cellular DNA damage checkpoint signaling to sensitize cancer chemotherapy. Treatment with PLE and PLEg significantly increased the cytotoxicity of doxorubicin (DOX) in A549 adenocarcinoma cells. PLE and PLEg reduced the phosphorylation of checkpoint proteins such as structural maintenance of chromosomes 1 (SMC1), checkpoint kinase 1 (Chk1), and p53 in DOX-treated cells. Moreover, PLE decreased the phosphorylation of ATM (ataxia telangiectasia mutated) in a dose-dependent manner. PLE, and especially PLEg, abrogated the G2/M checkpoint during DOX-induced DNA damage. These results suggest that PLEg specifically inhibited ATM-dependent checkpoint activation by DOX, and that PLEg might be a useful sensitizer in cancer chemotherapy.


Subject(s)
Cell Cycle Proteins/antagonists & inhibitors , DNA Damage , DNA-Binding Proteins/antagonists & inhibitors , Diospyros/chemistry , Doxorubicin/pharmacology , Plant Extracts/pharmacology , Plant Leaves/chemistry , Protein Serine-Threonine Kinases/antagonists & inhibitors , Tumor Suppressor Proteins/antagonists & inhibitors , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Adenocarcinoma of Lung , Antineoplastic Agents/pharmacology , Ataxia Telangiectasia Mutated Proteins , Cell Cycle Proteins/metabolism , Cell Division/drug effects , Cell Division/genetics , Cell Line, Tumor , Cell Survival/drug effects , DNA-Binding Proteins/metabolism , Flavonols/chemistry , Flavonols/isolation & purification , Flavonols/pharmacology , G2 Phase/drug effects , G2 Phase/genetics , Humans , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Phosphorylation/drug effects , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/isolation & purification , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/metabolism , Signal Transduction/drug effects , Tumor Suppressor Proteins/metabolism
14.
J Agric Food Chem ; 59(8): 3738-46, 2011 Apr 27.
Article in English | MEDLINE | ID: mdl-21391678

ABSTRACT

Proanthocyanidins and other polyphenols in the seeds and juice of boysenberry were quantitatively analyzed. Polyphenolic extracts were prepared from the waste seeds and commercial juice by chromatographic fractionation. Compositional analysis revealed that both extracts contained six polyphenolic classes: flavanol monomers, proanthocyanidins, anthocyanins, ellagic acid, ellagitannins, and flavonol glycosides. Ellagitannins were the most abundant polyphenols in both extracts. Proanthocyanidins were present as short oligomers consisting of dimeric and trimeric procyanidins and propelargonidins, with the most abundant component being procyanidin B4 in both extracts. Quantification by high-performance liquid chromatography-mass spectrometry (HPLC-MS) revealed that the seeds contained a 72-fold higher amount of proanthocyanidins than the juice. These results indicate that boysenberry fruits contain short oligomeric proanthocyanidins along with flavanol monomers and the seeds represent a good source of short oligomeric proanthocyanidins.


Subject(s)
Biopolymers/chemistry , Flavonoids/chemistry , Fruit/chemistry , Phenols/chemistry , Proanthocyanidins/chemistry , Biopolymers/analysis , Chromatography, High Pressure Liquid , Flavonoids/analysis , Phenols/analysis , Polyphenols , Proanthocyanidins/analysis , Spectrometry, Fluorescence , Tandem Mass Spectrometry
15.
Phytochem Anal ; 22(5): 403-10, 2011.
Article in English | MEDLINE | ID: mdl-21413094

ABSTRACT

INTRODUCTION: Dried leaves of persimmon, traditionally consumed as a herbal tea in Japan, contain bioactive galloylated flavonol glycosides. Investigation of the seasonal compositional changes in these compounds is important for determining the optimum harvest time. OBJECTIVE: The three objectives were: (1) to elucidate the compositional changes of the flavonol glycosides in persimmon leaves collected in different seasons; (2) to develop an efficient method for separation of the constituents; and (3) to compare their antioxidant activities. METHODOLOGY: Fresh persimmon leaves were collected at different growth stages in 2007 and 2008 in Niigata, Japan. Total flavonols were extracted with 70% aqueous acetone followed by ethyl acetate partitioning, and were analysed by high-performance liquid chromatography. Enzymatic transformation and chromatographic fractionation was performed to isolate the individual flavonols. Two antioxidant assays were performed. RESULTS: Four nongalloylated flavonol glycosides were detected at the leaf-shooting stage, and four additional galloylated flavonol glycosides accumulated during leaf development, resulting in a total of eight constituents. Isolation of nongalloylated and galloylated constituents was successfully achieved through enzymatic transformation of the flavonol mixture using combinations of tannase, ß-glucosidase and ß-galactosidase, followed by chromatographic fractionation. The gallates were identified as regiospecific 2″-galloylated galactosides and glucosides of kaempferol and quercetin. A mixture of 2″-galloylated flavonol glycosides had a two-fold stronger antioxidant activity than the nongalloylated mixture. CONCLUSION: This study showed that four 2″-galloylated flavonol glycosides had accumulated in developing leaves of persimmon by the end of May through a rapid 2″-galloylation of the corresponding nongalloylated flavonol glycosides.


Subject(s)
Chromatography, High Pressure Liquid/methods , Diospyros/chemistry , Flavonols/isolation & purification , Free Radical Scavengers/isolation & purification , Glycosides/isolation & purification , Biphenyl Compounds/chemistry , Flavonols/chemistry , Free Radical Scavengers/chemistry , Glycosides/chemistry , Nuclear Magnetic Resonance, Biomolecular , Picrates/chemistry , Plant Leaves/chemistry , Seasons , Tandem Mass Spectrometry
16.
Biosci Biotechnol Biochem ; 74(7): 1380-5, 2010.
Article in English | MEDLINE | ID: mdl-20622463

ABSTRACT

The amounts and compositions of polyphenol in persimmon leaves and persimmon leaf tea were investigated. The predominant polyphenols in fresh leaves were water-soluble, and the contents reached a maximum (2.40% w/w) in June, and then gradually decreased. Separation of them followed by thiolytic degradation revealed that the major components were unique proanthocyanidin oligomers consisting of four heterogeneous extension units, including epigallocatechin-3-O-gallate. Persimmon leaf tea also contained similar proanthocyanidins with similar compositional units. Oral administration of starch with polyphenol concentrate of persimmon leaf tea resulted in a significant and dose-dependent decrease in the blood glucose level in Wistar rats. This effect is considered to be due to inhibition of pancreas alpha-amylase. These results indicate that persimmon leaf tea containing peculiar proanthocyanidins has a significant role in suppressing blood glucose elevation after starch intake, and that the best harvest time is June.


Subject(s)
Diospyros/chemistry , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Plant Leaves/chemistry , Water/chemistry , alpha-Amylases/antagonists & inhibitors , Animals , Blood Glucose/metabolism , Chromatography, High Pressure Liquid , Diospyros/metabolism , Enzyme Inhibitors/metabolism , Flavonoids/chemistry , Flavonoids/metabolism , Flavonoids/pharmacology , Male , Phenols/chemistry , Phenols/metabolism , Phenols/pharmacology , Plant Extracts/chemistry , Plant Extracts/metabolism , Plant Extracts/pharmacology , Plant Leaves/metabolism , Polyphenols , Proanthocyanidins/chemistry , Proanthocyanidins/metabolism , Proanthocyanidins/pharmacology , Rats , Rats, Wistar , Seasons , Solubility , Starch/administration & dosage
17.
J Food Sci ; 75(8): M509-14, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21535506

ABSTRACT

Using UV mutagenesis, 2 high-pressure (HP) sensitive (barosensitive) mutants of Saccharomyces cerevisiae were obtained. The HP inactivation of the mutants, as well as their parent strains, followed 1st-order kinetics in the range of 175 to 250 MPa within 600 s. Both mutants showed larger 1st-order inactivation rate constant values or significant loss of viabilities, compared with their parent strains in the pressure range tested. The inactivation rate constant value of one of the mutants was comparable with that of a previously reported highly barosensitive strain, which was generated by deletion of hsp104 in a trehalose deficient strain. The activation volume values of HP inactivation reactions in the 2 mutants were apparently equivalent with those of their parent strains. This suggested that the mutation did not bring drastic volume changes of the key molecules for HP inactivation. Their auxotrophic properties, growth, and ethanol fermentation were identical in mutant and parent strains. The mutants could therefore be useful for fermentations where control by HP processing is desired.


Subject(s)
Mutagenesis , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae/isolation & purification , Ultraviolet Rays , Ethanol/metabolism , Fermentation , Food Microbiology , Kinetics , Microbial Viability , Pressure , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism
18.
J Clin Biochem Nutr ; 45(1): 93-100, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19590713

ABSTRACT

The purpose of this study was to examine the effects of gamma-aminobutyric acid (GABA) in fermented drinking water prepared from sodium glutamate, vinegar, and dried bonito (FDWG) compared with placebo [vinegar and dried bonito without GABA (FDW)] and its safety in normotensive and mildly or moderately hypertensive volunteers. A double-blind, placebo-controlled, randomized study was conducted involving volunteers with normal (group-N) and mildly or moderately high (group-H) blood pressure (BP). After a pretreatment period of 2 weeks (weeks -2), the subjects received FDWG or FDW for 12 weeks followed by 4 weeks of no intake (weeks 16). In group-H, both FDWG and FDW significantly decreased systolic (SBP, -7.6 +/- 4.0 and -5.5 +/- 1.5 mmHg, p<0.05, respectively) and diastolic (DBP, -10.6 +/- 4.0 and -7.6 +/- 1.7 mmHg, p<0.01, respectively) BP compared to the baseline (0-week) value at 12 weeks, respectively. There were no abnormal changes in hematological or blood chemistry variables, urinalysis, heart rate, or body weight in the study groups. These findings indicated that vinegar and dried bonito with or without GABA might have an effect on BP in mildly or moderately hypertensive patients.

19.
Food Chem ; 110(2): 493-500, 2008 Sep 15.
Article in English | MEDLINE | ID: mdl-26049244

ABSTRACT

The effect of sugar moiety on anthocyanin metabolism was studied using anthocyanidin 3-rutinosides (cyanidin 3-O-rutinoside (Cy3R) and delphinidin 3-O-rutinoside (Dp3R)) and 3-O-glucosides (delphinidin 3-O-glucoside (Dp3G)). O-methylated Cy3R and Dp3R were detected in rat blood plasma after oral administration of Cy3R and Dp3R (100mg/kg body weight). On the basis of HPLC retention time and UV-visible spectra together with the data of our previous studies on the hydrophobic metabolites of anthocyanidin 3-O-glucosides, it was concluded that both 3'- and 4'-O-methyl Cy3R were metabolites of Cy3R. On the other hand, only 4'-O-methyl Dp3R was detected as hydrophobic metabolite of Dp3R. A group of hydrophilic metabolites was also detected in rat blood plasma after oral administration of anthocyanins (Dp3G, Cy3R and Dp3R) and their structures were determined to be extended glucuronides and their O-methyl analogues by tandem MS analysis. The amounts of extended glucuronides of Dp3G, Cy3R and Dp3R were less than those of cyanidin 3-O-glucoside (Cy3G) reported in our previous study. On the other hand, anthocyanidin-glucuronides (both cyanidin-glucuronide and delphinidin-glucuronide) were not detected after oral administration of Cy3R, Dp3R and Dp3G. These results indicated that both the type of sugar moiety and stability of aglycone largely affected phase II metabolism of anthocyanins, and also indicated that the type of sugar moiety did not affect the O-methylation metabolism but affected glucuronyl conjugation in both liver and small intestine.

20.
J Agric Food Chem ; 55(6): 2489-96, 2007 Mar 21.
Article in English | MEDLINE | ID: mdl-17319688

ABSTRACT

Many studies on the bioavailability of polyphenols have been reported. However, the relative urinary excretions of AC are also low, ranging from 0.004% to 0.1%. By contrast, other polyphenols show higher urinary excretion levels. Here, we studied the enhancing effects of phytic acid (IP6) on absorption of blackcurrant anthocyanins (BCAs) in rats and humans. In rats after oral administration of BCAs (as 241 mg of AC/kg body weight) in IP6 (0%, 0.25%, 0.5%, 1%, 2.5%) solution, the ACs recovery in urine was increased dependent on IP6 dose. These results suggest that the IP6 enhances gastrointestinal absorption of ACs. At the further analysis of IP6 enhancement effect in rat, whereas BCAs were normally passed through the stomach and duodenum within 2 h, in IP6 group, after 2-6 h post-administration, stomach and jejunum content's weights were specifically heavy, and large amounts of ACs were also detected in stomach, duodenum, and jejunum. These results suggested that the mixture of BCAs and IP6 reduced the gastrointestinal motility. Prolongation of ACs residue in gastrointestinal tract then caused the enhancing effects of IP6 on absorption of AC. In the human study, each subject was orally administrated a BCA beverage containing BCA concentrate (AC 4 mg/kg body weight), 1% of IP6, and 1% of sodium citrate as a pH stabilizer. Both the plasma level and the urinary excretion of AC were increased as compared to BCA administration without IP6. AC intake with IP6 may increase the bioavailability of AC to the comparative level as other polyphenols. Yet, phytic acid, being a strong chelator of important minerals, contributes to mineral deficiencies. An interference with iron uptake has been reported. Safety tests are therefore necessary before high dose IP6 can be used in foods.


Subject(s)
Anthocyanins/pharmacokinetics , Intestinal Absorption/drug effects , Phytic Acid/administration & dosage , Adult , Animals , Anthocyanins/urine , Biological Availability , Dose-Response Relationship, Drug , Humans , Male , Rats , Rats, Wistar
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