Three acidic growth inhibitors were isolated from leaves of peanut and were identified as ferulic acid, p-cumaric acid and salicylic acid, respectively. 相似文献
The mass spectra of pestalotin and some related 4-methoxy-5,6-dihydro-α-pyrones, each containing a substituent at the C–6 position, have been studied. The prominent peak was observed commonly at m/e 127 and was proved characteristic of the pyrone ring. 相似文献
New types of stable chrysanthemic acids and esters were synthesized, and their 13C-NMR were examined and fully analyzed. The configurations of the cyclopropanecarboxylic acid and halomethylvinyl group were reflected on the spin-lattice relaxation time of the substituted methyl carbon involved in their structure. The long-range spin-spin coupling constants (3JCH) correlated well to the NOE and T1 measurements, which can generally be used to distinguish the geometry of the substituted double bond. 相似文献
Three isocoumarin compounds (BV 1, 2 and 3) were isolated from the cultural broth of Aspergillus oniki 1784. BV 1 was mellein (3-methyl-8-hydroxy-3,4-dihydroisocoumarin). BV 2 and 3 were assigned to be 3-methyl-4,8-dihydroxy-3,4-dihydroisocoumarin, 3-methyl-3,8-dihydroxy-3,4-dihydroisocoumarin, respectively. These two compounds (BV 2, 3) were newly isolated. Also another component named BV 4 was proved to be 6-methylsalicylic acid. 相似文献
The incorporation of 14C-methanol, 14C-formaldehyde, 14C-formate and 14C-bicarbonate into a methanol-utilizing yeast, Candida N–16, was examined by paper-chromato-graphy and radioautography.
At the earliest time period examined, the highest percentage of radioactivity fixed from 14C-methanol or 14C-formaIdehyde into methanol-grown cells was found in fructose phosphate. The percentage distribution of radioactivity in fructose phosphate decreased as time elapsed. The radioactivity fixed from these compounds into glucose-grown cells was negligible compared with that fixed into methanol-grown cells.
The incorporation of 14C-formate into methanol-grown cells was extremely low. The highest percentage of radioactivity fixed for short time incubation was found in serine. The incorporation pattern of glucose-grown cells was similar to that of methanol-grown cells.
At the earliest time period, over 70% of radioactivity fixed from 14C-bicarbonate into methanol- or glucose-grown cells was found in aspartate.
These results suggest that in Candida N–16 methanol is specifically assimilated by a route with hexose phosphate as a primary stable intermediate.
Variations in lipid components of washings and homogenate of pressed baker’s yeast were investigated during the storage of pressed baker’s yeast at 30°C. Washings represents the substances which had leaked out from cells. Homogenate represents those contained in whole cells. Lipids in yeast washings increased toward softening, the phospholipids in yeast homogenate decreased continuously during storage. Two stages, an earlier period of storage (Stage I) and a later period of storage (Stage II) were observed in the degradation of phospholipids. Free fatty acid which was the main degradation product of phospholipid accumulated in Stage II, particularly at softening. The order in phospholipid degradation was PC>PE>PI + PS (PI>PS). Moreover, when washings of stored yeast at softening were assayed using 14C-acyl PC, the release of 14C-acyl fatty acid was observed.These results suggest that phospholipids were degraded by some phospholipid-deacylating enzymes toward softening. From the results of lipid analysis, we inferred that the responsible enzymes were phospholipases. 相似文献
β-Ionone (I) was oxidized to 2,3-epoxy-/β-ionone (II), which was converted to 2,3-dihydroxy-β-ionone (III) by acid treatment. III was reduced to 4-(1,2-dihydroxy-2,6,6-trimethylcyclohexan-1-yl)-2-butanol (V), which was converted, by oxidation, to cis- and trans-theaspirone (1-oxa-8-oxo-2,6,10,10-tetramethyl spiro-(4,5)-6-decene) (VII-A), (VII-B) and dihydroactinidiolide (2-hydroxy-2,6,6-trimethylcyclohexyliden-1-acetic acid lactone) (IX). 相似文献