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131.
132.
Group A saponins are the principal factors underlying the undesirable bitter and astringent tastes in soybean food products. Therefore, the genetic reduction or elimination of the undesirable tastes is of great significance in soybean taste breeding. Using thin‐layer chromatography and liquid chromatography–mass spectrometry, we identified a novel mutant lacking group A saponins in a wild soybean (Glycine soja Sieb. & Zucc.), reflecting the failed arabinose binding of arabinosyltransferase to the C‐22 hydroxyl group, consequently leading to a lack of group A saponins and the concomitance expression of two new components A‐αg and KA‐αg in seeds. The C‐3 glycosylated soyasapogenol A (SS‐A), A‐αg, is a steady precursor compound in biosynthesis of Aa and Ab types in the seeds of soybean plants and exhibits stable inheritance. In this study, we observed a critical step necessary for arabinose binding to the C‐22 hydroxyl group in the biosynthetic pathway of group A saponins and identified an important germplasm accession for the genetic improvement in the tastes of soybean milk and processed soybean foods.  相似文献   
133.
The mid-gut gland of scallop Patinopecten yessoensis has been discarded in scallop processing factories as a fishery waste and various attempts have been made to turn the waste into valuable resources. In the present study, we tried to use mid-gut gland drips from scallop as a source of β-1,3-glucanase. The mid-gut gland drips were collected in a local fishery factory in Yubetsu-cho, Hokkaido Prefecture. β-1,3-Glucanase was purified from the mid-gut gland drips by ammonium sulfate fractionation followed by successive chromatography on Toyopearl Phenyl-650M and Toyopearl DEAE-650M. The scallop β-1,3-glucanase, named PyLam38 in the present study, showed a molecular mass of approximately 38 kDa by sodium dodecylsulfate-polyacrylamide gel electrophoresis, and hydrolyzed laminarin, a β-1,3-glucan from Laminaria sp., producing laminaribiose and glucose with an optimal pH and temperature of 6.0 and 45°C, respectively. PyLam38 exhibited high transglycosylation activity toward various accepter substrates such as monosaccharides, alcohols and xylooligosaccharides. Thus, PyLam38 was found to be useful for the production of various novel heterooligosaccharides consisting of laminarioligosaccharides and various accepters.  相似文献   
134.
This study reported detailed clinical effects of bovine lactoferrin on 2 canine littermates (1 female and 1 male) with familial neutrophil dysfunction and an investigation of their genetic background. Clinical signs caused by severe upper respiratory bacterial infections were observed in these dogs. Oral administration of bovine lactoferrin for a long duration improved their clinical signs (severe uveitis in the female dog and coughing from pneumonia in the male dog). Their backcross dogs that have the same father didn't show clinical signs of bacterial infection. Neutrophil function tests revealed that the backcross dogs didn't have any disorders. It is likely that abnormal clinical signs are associated with neutrophil dysfunction in the colony, and the mother dog of these cases might be the genetic carrier of this dysfunction.  相似文献   
135.
The effect of environmental acidification on Ibaraki virus (IBAV) infection was tested using endosomal inhibitory chemicals and low pH treatment. Treatment of target cells with endosomal inhibitors significantly decreased the progeny virus production. IBAV outer capsid proteins, VP5 and VP2, were removed from virion when purified IBAV was exposed to low pH environment. Further experiment showed that the exposure to low pH buffer facilitated IBAV infection when the cellular endosomal pathway was impaired by bafilomycin A1. Results obtained in this study suggest that acidic environment is essential to initiate IBAV infection.  相似文献   
136.
Fourteen kinds of alkyl esters of 2-endo-hydroxy-1,8-cineole were synthesized, with yields of 57.8-98.0%. Each ester had a characteristic and unique odor. Especially, the tert-butyl acetate of 2-endo-hydroxy-1,8-cineole had the most interesting odor of all the synthetic esters. The antimicrobial and bactericidal activities of these synthetic esters against test bacteria (Staphylococcus aureus, Escherichia coli, and Pseudomonas fluorescens) were examined using the broth dilution method. As a result, the tert-butyl acetate of 2-endo-hydroxy-1,8-cineole showed the highest antimicrobial and bactericidal activities against all kinds of the test bacteria.  相似文献   
137.
138.
The effects of cobalt chloride on the production of trichothecene and ergosterol in Fusarium graminearum were examined. Incorporation experiments with (13)C-labeled acetate and leucine confirmed that both 3-acetyldeoxynivalenol and ergosterol were biosynthesized via a mevalonate pathway by the fungus, although hydroxymethyl-glutaryl CoA (HMG-CoA) from intact leucine was able to be partially used for ergosterol production. Addition of cobalt chloride at concentrations of 3-30 μM into liquid culture strongly enhanced 3-acetyldeoxynivalenol production by the fungus, whereas the amount of ergosterol and the mycelial weight of the fungus did not change. The mRNA levels of genes encoding trichothecene biosynthetic proteins (TRI4 and TRI6), ergosterol biosynthetic enzymes (ERG3 and ERG25), and enzymes involved in the mevalonate pathway (HMG-CoA synthase (HMGS) and HMG-CoA reductase (HMGR)) were all strongly up-regulated in the presence of cobalt chloride. Precocene II, a specific trichothecene production inhibitor, suppressed the effects of cobalt chloride on Tri4, Tri6, HMGS, and HMGR, but did not affect erg3 and erg25. These results indicate that cobalt chloride is useful for investigating regulatory mechanisms of trichothecene and ergosterol production in F. graminearum.  相似文献   
139.
The relationship between the growth speed and wood properties of Pinus merkusii was investigated using 34-year-old trees planted in Indonesia in an attempt to promote the establishment of plantation of this species. The trees in the test plot were categorized as fast, middle, or slow growing according to the mean stem diameter and standard deviation in the plot. Five trees were selected from each category to investigate the effects of the growth rate on the wood properties [basic density (BD) and compressive strength parallel to the grain in a 5-mm-diameter core sample (CS)]. No significant correlation was recognized between the stem diameter and the stress wave velocity of trees. Clearly lower values of BD and CS were found in slow-growing trees than in fast- and middle-growing trees. The BD of xylem near the pith was reduced by extraction with organic solvent. BD after extraction and CS gradually increased from pith to bark. The results obtained in this study clarified that an early selection of trees with high BD is possible by using the BD after extraction at 4 cm from the pith.  相似文献   
140.
This survey explores the grief associated with the loss of a pet, and was carried out using a self-administered questionnaire. The questionnaires were handed out to 50 bereaved pet owners attending a public animal cremation service, and we received 18 responses. Participants responded within 0 to 44 (median 4) days of the death of their pet. Although most mental health problems immediately following mourning are presumed to be normal grief reactions, on the basis of several psychiatric scales, 8 of the 16 valid responses indicated depression and/or neurosis. Statistical analyses showed that the following factors were significantly associated with grief reactions: age of owner, other stressful life events, family size, age of deceased animal, rearing place, and preliminary veterinary consultation.  相似文献   
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