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111.
Aiming to get useful steroidal alkaloids by tissue culture of Solanum laciniatum Ait., indefinitely growing callus tissue was prepared from the mother plant. Some nutritional requirements for the growth of the callus tissue were studied. By examining steroidal compounds in callus culture, cholesterol, stigmasterol, β-sitosterol, lanosterol, squalene, diosgenin and a new steroidal alkaloid were found to be formed in the callus culture. The new steroidal alkaloid was found to be solasodine derivative containing rhamnose and other unidentified sugars.  相似文献   
112.
A S-PI(Pepstatin Ac)-insensitive carboxyl proteinase was found in culture filtrate of a Xanthomonas sp. bacterium. The carboxyl proteinase was highly purified and about 100 mg of the enzyme was obtained from 601 of culture filtrate, with a recovery of 25%. The optimum condition for the action of the purified enzyme toward casein was approx. pH 2.7 and its activity was not inhibited by any of such carboxyl proteinase inhibitors as Pepstatin, S-PI, and DAN but EPNP inhibited it. Such behavior of the enzyme against inhibitors resembles that of Pseudomonas sp. carboxyl proteinase, the first found from a bacterium. Some differences were observed, however, in their properties such as optimum pH, isoelectric point, and amino acid composition.  相似文献   
113.
Biological availability of 23 alcohols, 16 aldehydes and 2 ketones was compared by the mini-test with chicks. Chicks can utilize methanol and ethanol, but not the alcohols of carbon chain from 3 to 9. Lauryl and myristyl alcohols were well utilized but those of higher carbon chain than 14 were not, mainly due to low digestibility. Glycerol and D-sorbitol were well utilized but not 4 other poly alcohols tested. Aldehydes and ketones with free carbonyl group showed low availability or even toxicity, but their derivatives with masked group showed no detrimental effect. Acetaldehyde, acetal and aldehydes of carbon chain longer than 9 were partially utilized.  相似文献   
114.
A polyuronide, main component of the water extract of achine of Ficus awkeotsang MAKINO (on-gyo-tye), was purified by ion-exchange chromatography on DEAE-cellulose. The polyuronide (Fraction IB) is homogeneous electrophoretically and consists mainly of galacturonic acid. Optical rotation of Fraction IB is and content of methoxyl group is trace. In periodate oxidation of Fraction IB, molar ratio of galacturonic acid residue and periodate consumption was 1, and formic acid formation was very small. Periodate oxidation product of Fraction IB was oxidized further with bromine and the resulted substance was hydrolyzed. In the hydrolyzate, presence of large amount of tartaric and glyoxylic acids and small amount of tartronic acid were detected by paper chromatography. Reduced viscosity of aquous solution of Fraction IB increased with decreasing of the concentration of Fraction IB solution. From these results, it was deduced that Fraction IB has a linear structure of 1→4 linkage of d-galacturonic acid, probably α-linkage.  相似文献   
115.
Nodakenetin and marmesin were synthesized from β-resorcylaldehyde through 2-(α-hy-droxyisopropyl)-6-hydroxycoumaran.  相似文献   
116.
117.
A Streptomyces-pepsin inhibitor (S-PI or Pepstatin Ac), and DAN-insensitive carboxyl proteinase was found in a still culture filtrate of Lentinus edodes. The new carboxyl proteinase was purified, and about 9 mg purified enzyme was obtained from 19 liters of culture filtrate, with 11% recovery. The enzyme showed a single band on polyacrylamide gel electrophoresis. The molecular weight and isoelectric point were 40,000 and pH 4.2, respectively. The enzyme did not contain histidine and was composed of 387 amino acid residues. The enzyme was most active between pH 2.7 ~ 2.9, and stable over a pH of 3.2 ~ 5.2 for 3 hr at 37°C. The enzyme was not inhibited by S-PI or synthetic pepsin inhibitors such as DAN and EPNP. The physicochemical and enzymological properties were very similar to those of Scytalidium lignicolum carboxyl proteinase A, which was reported to be an S-PI-, and DAN-insensitive carboxyl proteinase.  相似文献   
118.
Sites of restriction endonucleases were mapped on pOAD2, a plasmid harbored in Flavobacterium sp. KI72. The plasmid codes 6-aminohexanoic acid cyclic dimer hydrolase and 6-aminohexanoic acid linear oligomer hydrolase. pOAD2 (molecular weight: 28.8 megadaltons [Mdal]) had 6 HindIII and 5 EcoRI sites, which were located at 0, 8.4, 8.9, 11.1, 19.0 and 25.0 Mdal (for HindIII) and 3.3, 5.4, 20.4, 20.8, 22.6 Mdal (for EcoRI). A mutant which could not grow on 6-aminohexanoic acid cyclic dimer but grew on the linear dimer as the sole carbon and nitrogen source harbored a deletion plasmid pOAD21 derived from pOAD2. By comparing the restriction sites of these two plasmids, the deleted region was localized on which the 6-aminohexanoic acid cyclic dimer hydrolase was coded.  相似文献   
119.
Addition of γ-aminobutyric acid (GABA) and angiotensin converting enzyme (ACE)-inhibitory peptides to the pickles was studied in order to develop a new type of pickles that reduce blood pressure. Based on the outcome of these studies, a new type of fermentation bed composed of rice bran and white miso has been successfully developed. The advantage of such pickles is that they not only contain both GABA and ACE-inhibitory peptides, but also that their taste and flavor are excellent, with colors close to the original ones. The new type of pickles could temporarily reduce blood pressure in two types of rats, spontaneously hypertensive rats and NaCl-sensitive model rats. Thus, the newly developed pickles appear to be beneficial for pickle business.  相似文献   
120.
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