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141.
The amylomaltase from Escherichia coli IFO 3806 was purified to homogeneity seen by SDS- polyacrylamide gel electrophoresis after DEAE-Sephadex, Ultrogel AcA 44, hydroxylapatite, and 1,6- hexane-diamine-Sepharose 4B column chromatographies. The molecular weight of the purified enzyme was 93,000 by SDS-polyacrylamide gel electrophoresis. The enzyme was most active at pH 6.5 and at 35°C, and stable up to 45°C at pH 7.0 and from pH 6.0 —7.3 at 40°C on 30min incubation. The enzyme acted on maltotetraitol, maltopentaitol, and maltosylsucrose besides maltooligosaccharides, but did not act on maltitol, maltotriitol, glucosylsucrose, isomaltose, panose, isopanose, or isomaltosyl- maltose. This enzyme did not catalyze hydrolytic action on maltotetraitol, maltopentaitol, or maltosylsucrose.  相似文献   
142.
A bacterium, (El7), has been found to form new amino acid, when grown in well aerated medium containing ethanol, n-propanol or n-butanol as a sole source of carbon. The new compounds were isolated and purified and their structures were investigated by elementary analyses, infrared spectra, NMR analyses, mass spectra and determination of their degradation products. The amino acids formed from ethanol, n-propanol and n-butanol have now been shown to be O-ethyl-l-homoserine, O-propyl-l-homoserine and O-butyl-l-homoserine, respectively.  相似文献   
143.
Succinoglucan, a succinylated polysaccharide produced by Alcaligenes faecalis var. myxogenes 10C3, was partially hydrolyzed with acid. Fractionation of the neutral oligosaccharides gave cellobiose, gentiobiose, laminaribiose, laminaritriose, 6-O-β-laminaribiosylglucose, 6-O-β-laminaritriosylglucose, and 3-O-β-cellobiosylgalactose, confirming the previous results that the polysaccharide consists of β-(l→3)-linked, (1→4)-linked and (1 →6)-linked d-glucose residues, and β-(1→3)-linked d-galactose residues.

Possible structural features of succinoglucan were discussed on the basis of the above and previous results obtained by Smith degradation.  相似文献   
144.
Many strains of yeast which can utilize n-alkanes as the sole source of carbon were isolated from flowers and fruits. Among them, a strain, OH23, identified as Candida tropicalis, formed acidic substances from n-alkanes. The principal products from n-alkanes with odd and even numbers of carbons were identified as glutaric and adipic acids, respectively. The culture conditions for their formation were investigated. n-Pentadecane and n-hexadecane were the best substrates for the formation of glutaric and adipic acids, respectively. Yields of 170 mg of glutaric and 64 mg of adipic acid were obtained from 100 ml of media containing 4% (v/v) n-pentadecane and n-hexadecane, respectively, and 0.5% casamino acids.  相似文献   
145.
Twelve strains of lactose-fermenting yeast isolated from raw milk were evaluated on β-galactosidase producing ability. The enzymes from the four strains (Tolulopsis versatilis M6, Tolulopsis sphaerica J28, Candida pseudotropicalis B57 and A60), selected by high productivity, showed very similar properties and were characterized by a pH optimum of 7.0 or 7.5 and a relatively low optimal temperature of 30°C. The molecular weights were estimated by gel filtration to be 200,000-233,000. The Km values for o-nitrophenyl-β-d-galactopyranoside were 3.45 mm, 2.09 mm, 3.45 mm and 2.82 mm for enzymes from M6, J28, B57 and A60, respectively. All enzymes were activated by Mn2+ and inhibited by Mg2+, Zn2+ and Ca2+. The enzymes are sulfhydryl dependent and were completely inhibited by Hg2+ and sulfhydryl reagents. The yeasts may be a potential source for the enzyme for industrial use.  相似文献   
146.
Strand breakages of mammalian cellular chromosomal DNA with aromatic reductones were ascertained by use of a cultured cell strain of the rat fetal lung (RFL). The mode of the breakages was investigated by ultracentrifugal analyses. The reductones induced the breakages of the cellular DNA in two different fashions; one is single strand breaks and another double strand breaks. Although the single strand breaks were rapidly repaired, double strand breaks were only partially repaired. Both breaks were not cytocidal. Some physiological alterations were observed to follow the strand breaks.  相似文献   
147.
The cDNA encoding a putative xylose reductase (xyrA) from Aspergillus oryzae was cloned and coexpressed in the yeast Saccharomyces cerevisiae with A. oryzae xylitol dehydrogenase cDNA (xdhA). XyrA exhibited NADPH-dependent xylose reductase activity. The S. cerevisiae strain, overexpressing the xyrA, xdhA, endogenous XKS1, and TAL1 genes, grew on xylose as sole carbon source, and produced ethanol.  相似文献   
148.
Previously, some changes were noticed in energy metabolism of rats fed a low casein diet. In connection with these phenomena, influence of a low casein diet on the composition and amounts of free fatty acids in liver homogenate after autolyzing for a few hours was investigated. For the measurement of free fatty acids, they were purified by a method with some devices in purification procedure using KOH. It was found that amounts of free fatty acids in liver homogenate after autolyzing for a few hours were lower in rats fed a low casein diet.  相似文献   
149.
All four stereoisomers of 10,14-dimethyloctadec-1-ene, a sex pheromone component of the apple leafminer (Lyonetia prunifoliella: Lepidoptera), were synthesized starting from (R)- and (S)-propylene oxide by applying stereospecific inversion of chiral secondary tosylates as a key step. Field evaluation showed that male moths of the Japanese population were selectively attracted by the (10S,14S)-isomer and that the activity was not inhibited by the enantiomer.  相似文献   
150.

Background

This study aims to examine the relationship between tyrosine and phenylalanine intake at breakfast as precursors of dopamine, and scores on the Torsvall-Åkerstedt Diurnal Type Scale and of mental health in Japanese infants aged 2 to 5 years.

Results

An integrated questionnaire was administered to parents of 1,367 infants attending one of ten nursery schools governed by Kochi City or a kindergarten affiliated with the Faculty of Education at Kochi University (775 answers for analysis: 56.7%) in May and June 2008. Questionnaires included the Torsvall-Åkerstedt Diurnal Type Scale and questions on sleep habits (onset, offset, quality, quantity, and so on), meal habits (content and regularity of timing), and mental health (depressive states). Amount of tyrosine and phenylalanine intake was calculated based on a breakfast content questionnaire and data on the components of amino acids in foods. Infants who ingested more than 800 mg of tyrosine or phenylalanine at breakfast per meal were more morning-type than those who ingested less than 800 mg (ANOVA: P= 0.005). However, this relationship disappeared in the ANCOVA analysis (with the covariance of tryptophan intake, P= 0.894). Infants who ingested more than 800 mg of the two amino acids at breakfast showed significantly higher mental health scores (lower frequency of depressive states) than those who ingested less than 800 mg (ANOVA: P = 0.004). This relationship remained significant when ANCOVA analysis was performed with the covariance of tryptophan (ANCOVA: P= 0.017).

Conclusions

These results suggest that tyrosine and phenylalanine ingested at breakfast are not related with circadian phase, but are relate with mental health in infants.  相似文献   
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