Formate-producing capacity provided by reducing ability of Streptococcus thermophilus nicotinamide adenine dinucleotide oxidase determines yogurt acidification rate.

Yogurt is made by fermenting milk with 2 lactic acid bacteria, Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus. To comprehensively understand the protocooperation mechanism between S. thermophilus and L. bulgaricus in yogurt fermentation, we examined 24 combinations of cocultures comprising 7 fast- or slow-acidifying S. thermophilus strains with 6 fast- or slow-acidifying L. bulgaricus strains. Furthermore, 3 NADH oxidase (Nox)-deficient mutants (Δnox) and one pyruvate formate-lyase deficient mutant (ΔpflB) of S. thermophilus were used to evaluate the factor that determines the acidification rate of S. thermophilus. The results revealed that the acidification rate of S. thermophilus monoculture determined the yogurt fermentation rates, despite the coexistence of L. bulgaricus, whose acidification rate was either fast or slow. Significant correlation was found between the acidification rate of S. thermophilus monoculture and the amount of formate production. Result using ΔpflB showed that the formate was indispensable for the acidification of S. thermophilus. Moreover, results of the Δnox experiments revealed that formate production required Nox activity, which not only regulated dissolved oxygen, but also the redox potential. The Nox provided the large decrease in redox potential required by pyruvate formate-lyase to produce formate. A highly significant correlation was found between formate accumulation and Nox activity in S. thermophilus. In conclusion, the formate production ability provided by the action of Nox activity determines the acidification rate of S. thermophilus, and consequently, regulates yogurt coculture fermentation.

The critical role of urease in yogurt fermentation with various combinations of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus.

The protocooperation between Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus relies on metabolite exchanges that accelerate acidification during yogurt fermentation. Conflicting results have been obtained in terms of the effect of the Strep. thermophilus urease and the NH3 and CO2 that it generates on the rate of acidification in yogurt fermentation. It is difficult to perform a systematic study of the effects of urease on protocooperation because it is necessary to distinguish among the direct, indirect, and strain-specific effects resulting from the combination of the strains of both species. To evaluate the direct effects of urease on protocooperation, we generated 3 urease-deficient mutants (ΔureC) of fast- and slow-acidifying Strep. thermophilus strains and observed the effects of NH3 or CO2 supplementation on acidification by the ΔureC strains. Further, we examined 5 combinations of 3 urease-deficient ΔureC strains with 2 CO2-responsive or CO2-unresponsive strains of L. bulgaricus. Urease deficiency induced a shortage of ammonia nitrogen and CO2 for the fast- and slow-acidifying Strep. thermophilus and for the CO2-responsive L. bulgaricus, respectively. Notably, the shortage of ammonia nitrogen had more severe effects than that of CO2 on yogurt fermentation, even if coculture with L. bulgaricus masked the effect of urease deficiency. Our work established (1) that urease deficiency inhibits the fermentative acceleration of protocooperation regardless of the Strep. thermophilus and L. bulgaricus strain combinations, and (2) that urease is an essential factor for effective yogurt acidification.

Long-term outcomes of hemostatic therapy for variceal bleeding and the challenge pending in the post-direct-acting antivirals era.

Background and study aims: This study evaluated the longterm outcomes of mainly endoscopic hemostatic therapy for gastrointestinal variceal bleeding and of the transition of hemostatic therapy. Patients and methods: Among 1,163 patients treated for gastrointestinal varices between April 2006 and June 2020, a total of 125 patients who underwent emergency hemostatic therapy were enrolled. Survival rates and secondary evaluation points were analyzed. Additionally, patients were classified into two groups: the previous and latter term. Patients' background, therapeutic method, and treatment results were compared between the groups. Results: 94.4% had cirrhosis. The average Child-Pugh score was 8.90. Successful primary hemostasis rate was 98.4%, and 5.6% died within 2 weeks, all with a Child-Pugh score ≥9. The respective 1- and 5-year survival rates for Child-Pugh grade A/B were 81.3% and 55.4%, while those for Child-Pugh grade C were 58.1% and 17.8%. Child-Pugh grade C or hepatocellular carcinoma was significantly associated with poor prognosis. In total, 21.6% experienced variceal re-bleeding; 62.9% of these cases were triggered by continued alcohol consumption. There was no significant difference in survival between patients with and without variceal re-bleeding and in post-treatment survival between the previous and latter terms. In the latter term, the number of cases caused by continued alcohol consumption significantly increased. Conclusions: Multidisciplinary treatment and continuation of proper management after hemostatic therapy for variceal bleeding are crucial. Continued alcohol consumption leads to variceal bleeding and re-bleeding; its proper management, including alcohol abstinence, is one of the major challenges left in the post-directacting antivirals era.

Virus activation and immune function during intense training in rugby football players.

Epidemiological studies suggest that highly trained athletes are more susceptible to upper respiratory tract infections (URTI) compared with the general population. Upper respiratory symptoms (URS) often appear as either primary invasion of pathogenic organisms and/or reactivation of latent viruses such as Epstein-Barr virus (EBV). The purpose of this study was to examine the relationship between EBV reactivation and the appearance of URS during intensive training in collegiate rugby football players. We evaluated EBV-DNA expression in saliva and examined the relationship between onset of URS and daily changes in EBV-DNA as well as secretory immunoglobulin A (SIgA) levels among 32 male collegiate rugby football players during a 1-month training camp. The EBV-DNA expression tended to be higher in subjects who exhibited sore throat (p=0.07) and cough (p=0.18) than that of those who had no symptoms, although their differences were not significant. The SIgA level was significantly lower 1 day before the EBV-DNA expression (p<0.05). The number of URS increased along with the EBV-DNA expression and decrease of SIgA levels. These results suggest that the appearance of URS is associated with reactivation of EBV and reduction of SIgA during training.

Exercise in, and adaptations to a cold environment have no effect on SIgA.

AIM: The authors hypothesized that inconsistent SIgA response to exercise is caused by the different adaptative status of subjects to a cold environment. The purposes of the study were to examine whether moderate-intense exercise in a cold environment decreases SIgA and whether adaptation to a cold environment has any effect on SIgA. METHODS: Young male skaters, short track (N=9) and inline (N=10), participated in this study. All subjects cycled for 60 min at 65% VO(2max) in cold (ambient temperature: 5 +or - 1 degrees Celsius, relative humidity 41 + or - 9%) and thermoneutral (ambient temperature: 21 + or - 1 degrees Celsius, relative humidity 35 + or - 5%) conditions. Saliva samples were collected as follows: before and after 1hour of environmental exposure; immediately, 30-min, 60-min and 120-min after the exercise. RESULTS AND CONCLUSIONS: Salivary SIgA and saliva flow rate decreased after the exercise in both groups only in thermoneutral conditions. The SIgA secretion rate did not decrease after moderate-high intensity exercise in a cold environment, and the SIgA response to exercise was not affected by the different adaptative status of subjects to the cold environment.

Photofunctionalised Ti6Al4V implants enhance early phase osseointegration.

OBJECTIVES: Ultraviolet (UV) light-mediated photofunctionalisation is known to improve osseointegration of pure titanium (Ti). However, histological examination of titanium alloy (Ti6Al4V), which is frequently applied in orthopaedic and dental surgery, has not yet been performed. This study examined the osseointegration of photofunctionalised Ti6Al4V implants. METHODS: Ti and Ti6Al4V implants were treated with UV light, and the chemical composition and contact angle on the surfaces were evaluated to confirm photofunctionalisation. The implants were inserted into femurs in rats, and the rats were killed two or four weeks after the surgery. For histomorphometric analysis, both the bone-implant contact (BIC) ratio and the bone volume (BV) ratio were calculated from histological analysis and microcomputed tomography data. RESULTS: The amount of carbon and the contact angle on both implants were significantly reduced after UV irradiation. The BIC ratios for both UV light-treated implants significantly increased at two weeks, but there was no significant difference at four weeks. There was no significant difference in the BV ratios between the UV light-treated and control implants at two or four weeks. CONCLUSIONS: This study suggests that photofunctionalisation of Ti6Al4V implants, similar to that of Ti implants, may promotes osseointegration in early but not in the late phase of osseointegration.Cite this article: R. Yamauchi, T. Itabashi, K. Wada, T. Tanaka, G. Kumagai, Y. Ishibashi. Photofunctionalised Ti6Al4V implants enhance early phase osseointegration. Bone Joint Res 2017;6:331-336. DOI: 10.1302/2046-3758.65.BJR-2016-0221.R1.

Bactericidal and antimicrobial effects of pure titanium and titanium alloy treated with short-term, low-energy UV irradiation.

OBJECTIVES: The surface of pure titanium (Ti) shows decreased histocompatibility over time; this phenomenon is known as biological ageing. UV irradiation enables the reversal of biological ageing through photofunctionalisation, a physicochemical alteration of the titanium surface. Ti implants are sterilised by UV irradiation in dental surgery. However, orthopaedic biomaterials are usually composed of the alloy Ti6Al4V, for which the antibacterial effects of UV irradiation are unconfirmed. Here we evaluated the bactericidal and antimicrobial effects of treating Ti and Ti6Al4V with UV irradiation of a lower and briefer dose than previously reported, for applications in implant surgery. MATERIALS AND METHODS: Ti and Ti6Al4V disks were prepared. To evaluate the bactericidal effect of UV irradiation, Staphylococcus aureus 834 suspension was seeded onto the disks, which were then exposed to UV light for 15 minutes at a dose of 9 J/cm2. To evaluate the antimicrobial activity of UV irradiation, bacterial suspensions were seeded onto the disks 0, 0.5, one, six, 24 and 48 hours, and three and seven days after UV irradiation as described above. In both experiments, the bacteria were then harvested, cultured, and the number of colonies were counted. RESULTS: No colonies were observed when UV irradiation was performed after the bacteria were added to the disks. When the bacteria were seeded after UV irradiation, the amount of surviving bacteria on the Ti and Ti6Al4V disks decreased at 0 hours and then gradually increased. However, the antimicrobial activity was maintained for seven days after UV irradiation. CONCLUSION: Antimicrobial activity was induced for seven days after UV irradiation on both types of disk. Irradiated Ti6Al4V and Ti had similar antimicrobial properties.Cite this article: T. Itabashi, K. Narita, A. Ono, K. Wada, T. Tanaka, G. Kumagai, R. Yamauchi, A. Nakane, Y. Ishibashi. Bactericidal and antimicrobial effects of pure titanium and titanium alloy treated with short-term, low-energy UV irradiation. Bone Joint Res 2017;6:108-112. DOI: 10.1302/2046-3758.62.2000619.

Isolation and characterization of addition products of alpha-tocopherol with peroxyl radicals of dilinoleoylphosphatidylcholine in liposomes.

alpha-Tocopherol was reacted with peroxyl radicals of phosphatidylcholine at 37 degrees C in liposomes. The phospholipid-peroxyl radicals were generated by the reaction of 1,2-dilinoleoyl-3-sn-phosphatidylcholine with a free radical initiator, 2,2'-azobis(2,4-di-methylvaleronitrile), under air. One peak corresponding to the reaction products of alpha-tocopherol with phosphatidylcholine-peroxyl radicals was isolated by reversed-phase high-performance liquid chromatography. Its structure was identified as a mixture of 8a-(phosphatidylcholine-peroxy)-alpha-tocopherones: 1-[9-(8a-peroxy-alpha-tocopherone)-10,12-octadecadienoyl]-2- linoleoyl-3-sn-phosphatidylcholine,1-[13-(8a-peroxy-alpha-tocopherone )-9,11-octadecadienoyl]-2-linoleoyl-3-sn-phosphatidylcholine, 1-linoleoyl-2-[9-(8a, peroxy-alpha-tocopherone)-10,12-octadecadienoyl]-3-sn-pho sph atidylcholine and 1-linoleoyl-2-[13-(8a-peroxy-alpha-tocopherone)-9,11-octadecadi enoyl]-3-sn- phosphatidylcholine. The results indicate that each alpha-tocopherol can trap two peroxyl radicals during the peroxidation of unsaturated phospholipid in liposomes.

Antioxidant activity of a novel vitamin E derivative, 2-(alpha-D glucopyranosyl)methyl-2,5,7,8-tetramethylchroman-6-ol.

A novel vitamin E derivative, 2-(alpha-D-glucopyranosyl)methyl-2,5,7,8-tetramethylchroman-6-ol (TMG), has excellent water-solubility (> 1 x 10[3] mg/ml). The antioxidant activity of TMG was investigated. Kinetic studies of the inhibition of radical-chain reaction of methyl linoleate in solution demonstrated that the peroxyl radical-scavenging activity was not changed by the replacement of phytiyl side chain of vitamin E to glucosyl group. TMG acted as an effective inhibitor on lipid peroxidation of egg yolk phosphatidylcholine (PC)-liposomal suspension induced by a water-soluble and a lipid-soluble radical generator, 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN). Its effectiveness was higher than that of ascorbic acid (AsA) when liposomal suspension was exposed to a lipid-soluble radical generator, AMVN. TMG also showed an excellent antioxidant activity on cupric ion-induced lipid peroxidation of PC-liposomal suspension, and suppressed the oxidation of rat brain homogenate which contained trace level of iron ion. On the other hand, AsA acted as a prooxidant on both the cupric ion-induced liposomal peroxidation and the oxidation of rat brain homogenate. When human plasma was exposed to either AAPH or AMVN, the accumulation of cholesteryl ester hydroperoxides was retarded by the addition of TMG.

Association analyses between genetic polymorphisms of endothelial nitric oxide synthase gene and hypertension in Japanese: The Suita Study.

OBJECTIVES: Endothelium-derived nitric oxide plays a key role in the regulation of vascular tone. Recently, endothelial nitric oxide synthase (eNOS) gene polymorphisms were reported to be associated with hypertension or coronary spasm. We investigated the association between the eNOS gene polymorphisms and hypertension in a large population-based sample of 4055 Japanese. DESIGN AND METHODS: We investigated two polymorphisms of the eNOS gene, Glu298Asp polymorphism of exon 7 and T(-786)C polymorphism of the promoter region. The genotype distribution in hypertensive subjects was compared to that in the other subjects. The influence of the genotype on blood pressure values was analyzed in the subjects not taking hypertensive medication. The promoter activities of the eNOS gene with the (-786)T or (-786)C allele were measured by a luciferase reporter gene assay. RESULTS: There was significant linkage disequilibrium between the two polymorphisms (P < 0.0001). The genotype distribution of the Glu298Asp or T(-786)C polymorphism did not differ between the hypertensive and the other subjects. No significant differences in the blood pressure of subjects not taking hypertensive medication were observed among the three genotypes of Glu298Asp or T(-786)C polymorphisms. No significant differences in the promoter activity were observed between bovine endothelial cells transfected with the (-786)T and (-786)C alleles. CONCLUSIONS: Our data suggested that these polymorphisms of the eNOS gene are unlikely to be major factors in the susceptibility to hypertension in the Japanese population studied.

Induction of a 31,000-dalton stress protein by prostaglandins D2 and J2 in porcine aortic endothelial cells.

Prostaglandin (PG) D2 and PGJ2 stimulated porcine aortic endothelial cells to synthesize a 31,000-dalton protein (termed p31) in a time- and concentration-dependent manner. The induction of p31 synthesis was specific for PGD2, PGJ2 and PGA1 among the various PGs tested. p31 was also synthesized in response to the thiol-reactive agent diethylmaleate and heavy metal sodium arsenite but not to high temperature treatment, platelet-derived growth factor, and 12-O-tetradecanoylphorbol 13-acetate. Using two-dimensional polyacrylamide gel electrophoresis, p31 induced by PGJ2 had an isoelectric point of 5.4, which overlapped exactly with that induced by by arsenite. These results taken together indicate that p31 represents one of the stress proteins whose expression is regulated primarily by thio-active compounds but not by hyperthermia. Furthermore, it was induced by PGD2 and PGJ2 in rat capillary endothelial cells, rat skin fibroblasts, and rat hepatocytes. The data obtained from this study suggest that p31 induced by PGD2 and PGJ2 may play a role in the metabolic regulation of many mammalian cells.

Effect of GABA (gamma-aminobutyric acid) on neurotransmission in inferior colliculus slices from the guinea pig.

Inferior colliculus (IC) slices from guinea pigs were prepared by cutting the IC parasagittally and incubating the obtained slices in the standard medium. Postsynaptic field potentials (PSFP) were recorded in the superficial layer of the pericentral nucleus (PN) by stimulating the deep layer of the PN. GABA (gamma-aminobutyric acid) and its agonists (muscimol and baclofen) and antagonist (bicuculline) were applied in the perfusion medium. GABA (1-12.5 mM), muscimol (1-200 microM) and (-)-baclofen (0.1-20 microM) reduced the amplitude of the PSFP in a dose-dependent manner. Bicuculline (1-10 microM) enhanced the amplitude of the PSFP and evoked the epileptiform burst discharge (EBD). The incubation of IC slices with methoxypyridoxin (100 microM) and 3-mercaptopropionic acid (100 microM) for 2 h reduced the GABA level of the slice to about 50% of the initial value, at which point a distinct EBD appeared. The application of GABA (5 mM) to the medium in this condition blocked the EBD completely. The removal of chloride from the medium as well as the application of furosemide (100 microM) enhanced the amplitude of the PSFP and also elicited the EBD; GABA application in this case did not block the EBD. These results indicate that GABA plays an inhibitory role in the IC, and that the reduction of GABA and the blockade of GABA function cause the appearance of EBD in the IC.

Enhancement of the oxygen consumption in the hippocampal slices of the guinea pig induced by glutamate and its related substances.

The effects of glutamate (Glu), kainate (Ka), and N-methyl-D-aspartate (NMDA) on the oxygen consumption of the hippocampal slices of the guinea pig were investigated. The oxygen consumption of slices at resting state was 8.43 mumol/g protein/min. Bath application of Ka (1 x 10(-8) to 1 x 10(-6) M), NMDA (1 x 10(-8) M to 1 x 10(-4) M), and Glu (1 x 10(-5) M to 5 x 10(-4) M) enhanced the oxygen consumption dose-dependently in the similar tendency although the effective doses varied for the different excitants. Subsequently the consumption was maximal at approximately 140% of the resting level. The enhancement of the oxygen consumption due to NMDA and Glu was antagonized by DL-2-amino-5-phosphonovaleric acid (APV) for NMDA and by glutamic acid diethylester (GDEE) and Joro spider toxin (JSTX) for Glu. From these results it was suggested that the increase of the oxygen consumption observed here must reflect the neuronal activation induced by these excitants.

Effects of temperature on the oxygen consumption in thin slices from different brain regions.

The oxygen consumption of brain slices from 12 different regions of the guinea pig brain was measured and the effects of temperature on the consumption was investigated. At 37 degrees C the oxygen consumption in cerebral gray matter and inferior colliculus was higher than that of other regions, whilst the consumption in cerebral white matter and brainstem was approximately half of that in cerebral gray matter. In any region lowering the tissue temperature from 37 to 28 degrees C reduced the oxygen consumption by 6-8% of the value obtained at 37 degrees C per one degree. At 21 degrees C the consumption was decreased to 15% of the value obtained at 37 degrees C. It is notable that the consumption in hippocampal slices tested was remarkably increased by raising the temperature up to 50 degrees C and no consumption was observed at 55 degrees C.

Effects of omeprazole and pirenzepine on enterochromaffin-like cells and parietal cells in rat stomach.

PURPOSE: The purpose of this study was to investigate the mechanism of the regulation of histamine synthesis in enterochromaffin-like cells, chemically and structurally, by treatment with omeprazole and pirenzepine. METHODS: The ultrastructures of enterochromaffin-like cells and parietal cells were examined in rats treated with oral omeprazole (20 mg/kg) or intraperitoneal pirenzepine (1 mg/kg) administration. Serum gastrin concentrations, mRNA levels of H+-K+-ATPase and histidine decarboxylase, and the fundic concentrations of somatostatin and histamine were determined. RESULTS: Pirenzepine treatment suppressed omeprazole-induced increases in serum gastrin levels and mRNA levels of H+-K+-ATPase and histidine decarboxylase. Pirenzepine also decreased omeprazole-induced increases of histamine concentration in fundic mucosa. Pirenzepine elevated somatostatin mRNA level, previously decreased by omeprazole treatment, in fundic mucosa. In the cytoplasm of enterochromaffin-like cells, omeprazole markedly reduced the numbers of vesicles and granules, but significantly increased their diameters, whereas pirenzepine treatment changed neither of these features. The densities and diameters of both vesicles and granules produced by treatment with omeprazole and pirenzepine were between those produced by treatment with omeprazole alone and pirenzepine alone. CONCLUSIONS: Omeprazole-induced hypergastrinemia and pirenzepine-induced somatostatin synthesis play important roles not only in histamine synthesis but also in ultrastructural changes in enterochromaffin-like cells.

Structural features of arabinogalactan-proteins from the fruit of Lycium chinense Mill.

In addition to the other arabinogalactan-proteins (AGPs) (Cp-1-C and -D) already reported, two kinds of AGP (Cp-2-B and Hp-2-C) were obtained from the fruit of Lycium chinense Mill. The ratio of arabinose to galactose was approximately 1:1 in both samples, and the carbohydrate was linked O-glycosidically to serine in Cp-2-B, and to both serine and threonine residues of the protein in Hp-2-C. The weight-average molecular weight was 71,000 for Cp-2-B and 120,000 for Hp-2-C. Both samples also contained non-reducing terminal 3-O- and 4-O-substituted galacturonic acids. The ratio of 6-O-substituted galactose (linear part) and 3,6-di-O-substituted galactose (branching point) was almost unity in both samples, being obviously different from the case of Cp-1-C (predominant in the branching domain) and Cp-1-D (predominant in the linear domain). These results offer fresh insight into the grouping of the AGPs, based on the ratio of 6-O- and 3,6-di-O-substituted galactosyl residues.

Structural study on an exocellular polysaccharide produced by Lactobacillus helveticus TY1-2.

Lactobacillus helveticus TY1-2 produced an exocellular polysaccharide when it was cultured in reconstituted skim milk. This polysaccharide is a high molecular weight heteropolymer of D-glucopyranosyl, D-galactopyranosyl, and 2-acetamido-2-deoxy-D-glucopyranosyl residues in the molar ratio 3.0:2.8:0.9. The primary structure of the polysaccharide was shown by glycose analysis, methylation analysis, Smith degradation, and NMR spectroscopy to be composed of branched heptasaccharide repeating units having the following structure: [formula: see text]

Structure of an exocellular polysaccharide of Lactobacillus helveticus TN-4, a spontaneous mutant strain of Lactobacillus helveticus TY1-2.

Lactobacillus helveticus strain TN-4, a spontaneous mutant strain of Lactobacillus helveticus TY1-2, produced an exocellular polysaccharide from reconstituted skim milk. On the basis of the results of methylation analysis, enzymatic digestion, mild Smith degradation, mild acid hydrolysis, acetolysis, and 1D and 2D 1H-NMR spectroscopy, it was concluded that the polysaccharide has a D-galactofuranose containing hexasaccharide repeating unit with the following structure: [formula see text]

Synthesis of 5-hydroxy-2-(beta-D-ribofuranosyl)pyran-4-one from a pyranulose glycoside.

The synthesis of 5-hydroxy-2-(beta-D-ribofuranosyl)pyran-4-one (9) is described. Treatment of pyranulose glycoside with bromine in carbon tetrachloride afforded brompyranulose glycoside in 90% yield. The reaction of (6S)- and (6R)-4-bromo-6-hydroxy-6-(2,3,5-tri-O-benzoyl-beta-D-ribofuranosyl)-6H- pyran-3-one (2) in acidic media was examined with the following results: the reaction of 2 with trifluoroacetic acid (TFA) in dioxane afforded a mixture of 5-hydroxy-2-(2,3,5-tri-O-benzoyl-beta-D-ribofuranosyl)pyran-4-one (3) and its furan derivative 5-hydroxy-2-{5-(benzoyloxy)methyl]furan-2-yl}pyran-4-one (4), but the use of hydrochloric acid formed the bromofurfural, 3-bromo-5-(2,3,5-tri-O-benzoyl-beta-D-ribofuranosyl)-2-furancarboxyal dehyde only. Acetylation of a mixture (3 and 4) with acetic anhydride facilitated product separation to give the corresponding acetates 5-acetoxy-2-(2,3,5-tri-O-benzoyl-beta-D-ribofuranosyl)pyran-4-one (5) and 5-acetoxy-2-{5-[(benzoyloxy)methyl]furan-2-yl}pyran-4-one (6). Treatment of 5 with hydrazine afforded 3-hydroxymethyl-6-(beta-D-ribofuranosyl)-1H-pyridazin-4-one in 43% yield. Debenzoylation of 5 with aq ammonia gave 9 in 50% yield.

Analysis of molecular species of glycolipids in fruit pastes of red bell pepper (Capsicum annuum L.) by high-performance liquid chromatography-mass spectrometry.

Five major glycolipid classes (acylated steryl glucoside, steryl glucoside, monogalactosyldiacylglycerol, digalactosyldiacylglycerol, and glucocerebroside) from fruit pastes of red bell pepper were separated by silica gel column chromatography. The molecular species of each glycolipid were separated and characterized by reversed-phase high-performance liquid chromatography coupled with on-line mass spectrometry using atmospheric pressure chemical ionization. The molecular species of steryl glucoside were beta-sitosteryl and campesteryl glucosides, and those of the acylated steryl glucoside were their fatty acid esters. The dilinolenoyl species was predominant in monogalactosyldiacylglycerol in addition to small amounts of another five molecular species, whereas digalactosyldiacylglycerol consisted of seven molecular species varying in their degree of unsaturation. The glucocerebroside class contained at least seven molecular species, which were characterized by proton nuclear magnetic resonance spectroscopy.