Persimmon fruit tannin-rich fiber reduces cholesterol levels in humans.

Bile acid-binding agents are known to lower blood cholesterol levels and have been clinically used for the treatment of hypercholesterolemia. We previously showed that tannin-rich fiber from young persimmon (Diospyros kaki) fruits had bile acid-binding properties. In this study, we performed a randomized, double-blind, placebo-controlled trial to investigate the hypocholesterolemic effects of tannin-rich fiber in humans. The subjects (n = 40, plasma total cholesterol levels 180-259 mg/dl) were divided into 3 groups and ingested cookie bars containing 0 g (placebo group, n = 14), 3 g (low-dose group, n = 13), or 5 g (high-dose group, n = 13) of tannin-rich fiber 3 times daily before meals for 12 weeks. Plasma total cholesterol levels decreased significantly in the low-dose (12 weeks, p < 0.005) and high-dose (6 weeks, p < 0.05; 12 weeks, p < 0.001) groups. In addition, plasma low-density lipoprotein cholesterol levels decreased significantly in the high-dose group (6 weeks, p < 0.05; 12 weeks, p < 0.001). These improvements were not accompanied by changes in plasma high-density lipoprotein cholesterol or plasma triglyceride levels. Our findings indicate that tannin-rich fiber from young persimmon fruits is a useful food material for treating hypercholesterolemia.

The antioxidative effect of fullerenes during the peroxidation of methyl linoleate in toluene.

The antioxidative effect of fullerenes C(60) and C(70) was examined by measuring the inhibition of methyl linoleate (MeL) peroxidation in toluene initiated by 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN). The fullerenes retarded the formation of MeL hydroperoxides and lowered the rate of propagation. The reaction rates of fullerenes with AMVN-derived peroxyl radicals were much higher than that of MeL. These results indicate that fullerenes can act as retarders of lipid peroxidation, though their activity is low compared with that of α-tocopherol.

Nationwide surveillance of antimicrobial susceptibility patterns of pathogens isolated from surgical site infections (SSI) in Japan.

To investigate the trends of antimicrobial resistance in pathogens isolated from surgical site infections (SSI), a Japanese surveillance committee conducted the first nationwide survey. Seven main organisms were collected from SSI at 27 medical centers in 2010 and were shipped to a central laboratory for antimicrobial susceptibility testing. A total of 702 isolates from 586 patients with SSI were included. Staphylococcus aureus (20.4 %) and Enterococcus faecalis (19.5 %) were the most common isolates, followed by Pseudomonas aeruginosa (15.4 %) and Bacteroides fragilis group (15.4 %). Methicillin-resistant S. aureus among S. aureus was 72.0 %. Vancomycin MIC 2 µg/ml strains accounted for 9.7 %. In Escherichia coli, 11 of 95 strains produced extended-spectrum ß-lactamase (Klebsiella pneumoniae, 0/53 strains). Of E. coli strains, 8.4 % were resistant to ceftazidime (CAZ) and 26.3 % to ciprofloxacin (CPFX). No P. aeruginosa strains produced metallo-ß-lactamase. In P. aeruginosa, the resistance rates were 7.4 % to tazobactam/piperacillin (TAZ/PIPC), 10.2 % to imipenem (IPM), 2.8 % to meropenem, cefepime, and CPFX, and 0 % to gentamicin. In the B. fragilis group, the rates were 28.6 % to clindamycin, 5.7 % to cefmetazole, 2.9 % to TAZ/PIPC and IPM, and 0 % to metronidazole (Bacteroides thetaiotaomicron; 59.1, 36.4, 0, 0, 0 %). MIC90 of P. aeruginosa isolated 15 days or later after surgery rose in TAZ/PIPC, CAZ, IPM, and CPFX. In patients with American Society of Anesthesiologists (ASA) score ≥3, the resistance rates of P. aeruginosa to TAZ/PIPC and CAZ were higher than in patients with ASA ≤2. The data obtained in this study revealed the trend of the spread of resistance among common species that cause SSI. Timing of isolation from surgery and the patient's physical status affected the selection of resistant organisms.

Bile acid-binding ability of kaki-tannin from young fruits of persimmon (Diospyros kaki) in vitro and in vivo.

The bile acid-binding ability of a highly polymerized tannin (kaki-tannin) extracted from dried-young fruits of persimmon (Diospyros kaki) was examined. The kaki-tannin was composed mainly of epicatechin, epigallocatechin, epicatechin-3-O-gallate and epigallocatechin-3-O-gallate. Bile acid-binding ability of kaki-tannin was examined against cholic acid, glycocholic acid, taurocholic acid and deoxycholic acid in vitro, and its effect on fecal bile acid excretion in mice was also examined. Although the bile acid-binding ability of kaki-tannin was weaker than that of cholestyramine, kaki-tannin adsorbed all the bile acids tested and significantly promoted fecal bile acid excretion in mice when supplied at 1% (w/w) in the diet.

Effects of antioxidants and additional emulsifiers on the stability of emulsified milk fat in the photo/radical oxidation system.

The effects of antioxidants on the oxidative deterioration of emulsified oils and fats differ depending on the oxidation conditions, oils and fats used, and type of emulsifier. In this study, milk fat was emulsified to obtain water-oil (O/W) emulsion using Tween20 as emulsifier. The antioxidative effects of several antioxidants with various lipophilic properties, such as δ-tocopherol (Toc), epigallocatechin gallate (EGCg), quercetin (Qu), green tea extract (GTE), and rooibos tea extract (RTE) were investigated, the effects of additional emulsifiers such as polyglycerol and sucrose esters of fatty acids on the oxidation stability of the emulsion were also investigated. Under oxidative conditions of 30°C in 650 lx, Toc was more effective than GTE in suppressing the increase of the peroxide value (PV, meq/kg) of the emulsified milk fat. Under these oxidative conditions, the antioxidative effect of GTE was enhanced by the addition of polyglycerol and sucrose esters of fatty acids. Under the oxidative conditions at 40°C in dark with 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) or 2,2'-azobis (2,4-dimethylvaleronitrile) (AMVN), Toc showed the most antioxidative effect on suppression of the increase of PV and anisidine value (AnV) of the emulsified milk fat. Furthermore, additional emulsifiers also showed suppressive effects on the increase of the PV and AnV of the emulsified milk fat even without any antioxidants. The effects of additional emulsifiers on the oxidative stability of O/W emulsions were enhanced with antioxidants such as Toc, EGCg, and Qu.

Reaction products of [60]fullerene during the autoxidation of methyl linoleate in bulk phase.

The antioxidative action of fullerenes has received much attention, but their reaction mechanism toward lipid-derived peroxyl radicals has not been well elucidated. In this study, the reaction products of [60]fullerene (C(60)) during the autoxidation of methyl linoleate (MeL) were isolated and their structures were characterized. MeL containing 0.1mol% C(60) was autoxidized at 60°C in bulk phase and two reaction products of C(60), 1 and 2, were obtained. The structure of 1 was the addition products of C(60) with 9-peroxyl-10-alkyl radicals of methyl (11E)-13-hydroperoxy-11-octadecaenoate (1a and 1b) and with 12-alkyl-13-peroxyl radicals of methyl (10E)-9-hydroperoxy-10-octadecaenoate (1c and 1d). 2 was a mixture of the addition products of C(60) with 9,11-dialkyl radicals of methyl 9,12-octadecadienoate (2a) and with 11,13-dialkyl radicals of methyl 9,12-octadecadienoate (2b). When MeL containing 0.1mol% C(60) was autoxidized at 60°C under air-sufficient and air-insufficient conditions, C(60) could suppress the formation of MeL hydroperoxides in both conditions. The reaction product of C(60) first formed was 2 even under air-sufficient conditions, and then 1 was accumulated. The results indicate that the primary antioxidative action of C(60) would be trapping of chain-initiating carbon-centered radicals of unsaturated lipid to form 2.

Impurity effects on lysozyme crystal growth.

Atomic force microscopy (AFM) and X-ray diffraction experiments have been combined to study the correlation between impurity incorporation, crystal surface morphology and crystal quality. Hen egg-white lysozyme has been used as a model protein, and covalently bound lysozyme dimer as a model impurity. AFM observation of the [101] crystal face revealed that the crystal surface clearly became rough when 5% impurity was added, and the steps disappeared as the impurity concentration increased to 10%. The crystal quality was evaluated by four factors: maximum resolution limit, /, Rmerge, and overall B factor. In every index, the crystal quality tended to degrade as the impurity concentration increased. The B-factor dropped significantly at 5% impurity; at the same time the step roughening was observed. This strongly suggested that the impurity incorporation affected the step growth mechanism and degraded the crystal quality.

Improvement of protein crystal quality by forced flow solution.

Flow experiments in growing protein crystals were conducted to clarify the influence of the solution flow on the crystal quality. Lysozyme crystals grown under various flow velocities were analyzed by using synchrotron radiation to assess the quality. As a result, the crystals grown under forced flow were of better quality than those grown in quiescent conditions.