Conditions of asymmetric hydrolysis of dl-menthyl acetate by Rhodotorula mucilaginosa were searched from the point of view of industrialization.
Kinako (roasted soybean flour), yeast extract and corn steep liquor were especially effective in the increase of esterase activity.
Optimum temperature for growth and for asymmetric hydrolysis were 27_??_29°C and 32_??_33°C and optimum pH for growth and for the reaction were around 7 and 7.5 respectively.
Activity was enhanced and its deviation lowered by the single cell isolation, which, however, by successive transplantations, was receded to the original level.
One of the UV irradiated strains showed ca. 70 percent higher activity than original strain. This strain liberated 44.4g of l-menthol per 24 hours from dl-menthyl acetate mixture in 1 l of culture medium in the best operating condition.

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The mechanisms of degradation of New Coccine (NC) were studied using the cellfree extracts of Bacillus cereus T-105 strain.
The crude extracts showed NC-degrading activity in the absence of oxygen. NC (0.01%) was able to function as an inducer and the NC-degrading enzyme activity increased remarkably by the addition of NC to the culture medium of the strain. The NC-degrading enzyme activity increased markedly by the addition of the substrates for dehydrogenase, such as glucose-6-phosphate, isocitrate, α-ketoglutarate, or malate, to the reaction mixture. These results suggested that the NC-degrading enzyme might be coupled with pyridine coenzyme-dependent dehydrogenase systems. The optimum pH and temperature for the NC-degrading enzyme activity were 8.0 to 8.5 and 40 to 45°C, respectively. The NC-reductase activity showed more specific dependency on NADPH than on NADH as an electron donor, and it required FAD or FMN as a cofactor but did not show requirement for riboflavin.

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The authors had reported that L-cysteine probably was formed from acetyl-L-methionine and L-serine through cystathionine pathway by the skin enzyme of rabbit, and the solution composed of acetyl-L-methionine and L-serine exhibited the effectiveness to the hair growth in rabbit. This report shows that, by the application of ³⁵S-acetyl-L-methionine and L-serine to the skin of rabbit and in vitro analysis of the metabolites of ³⁵S-compounds, ³⁵S-acetyl-L-methionine was absorbed into the hair tissues for many hours, and half ³⁵S-L-cystine was formed in vitro and in vivo. When total amount of ³⁵S in the hair was measured, the radiochemical activities were cleary shown as almost ³⁵S-L-cystine.

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Xylanase from Streptomyces sp. E-86 was purified by a procedure including DEAE-sephadex•cellulose treatment, QAE-sephadex column chromatography and gel filtration on a Biogel P-150 column. The purified enzyme was homogeneous on both Disc-electrophoretical and ultracentrifugal analyses.
Optimum pH and temperature for the enzyme activity were 5.5_??_6.2 and 55_??_60°C, respectively. Heating the enzyme solution for 30min at 55°C did not influence their stability, and the same treatment at 70°C resulted in the loss of 100% of original activity. The enzyme was stable in the range of pH from 4.5 to 10.5, but inactivated at pH values such as pH 2.8 or 11.5.
None of the metal ions accelerated the enzyme activity, and Cd²⁺, Sn²⁺, Pb²⁺ and Cu²⁺ inhibited partially the reaction. The xylanase was not inactivated by EDTA 2 Na, iodoacetic acid and pCMB.
When various xylooligosaccharides and their reduced derivatives were used as substrates, the higher oligomer was hydrolyzed much faster than the lower.
Activation energy on hydrolysis of xylotetraose and inactivation energy of the enzyme were 1.3×10⁴ cal and 1.2×10⁵ cal, respectively.
The enzyme had a sedimentation coefficient of 4.1 S at 0.9% protein concentration, and the molecular weight was determined to be 40, 500 from the Archibald method using ultracentrifugal analysis. Isoelectric point and E^1%_1cm at 280 nm were pH 7.3 and 13.7, respectively.

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In this report, the difference of digestibility and the hydrolysis products on various xylans by the purified xylanase from Streptomyces sp. E-86, and the mode of action of the enzyme on insoluble xylan (hardwood) and xylooligosaccharides were described.
When the enzyme acted on xylan which was only composed of xylose residue such as hardwood and cotton seeds xylans, the extent of maximum hydrolysis was higher than that of arabinoxylans from corncobs, and the hydrolysis products mainly consisted of xylose and xylobiose. In the case of the arabinoxylans, main products were similarly xylose and xylobiose, but an appreciable amount of unknown pento-oligosaccharides was also observed on paper chromatography.
The course of hydrolysis of the insoluble xylan by this enzyme was presumed as follows; xylan→xylotriose>xylotetraose>xylobiose>xylopentaose>xylohexaose→xylobiose>xylotriose>xylose→xylobiose_??_xylose→xylose>xylobiose.
When xylotriose was used as substrate, only xylobiose, but not detectable amount of xylose even in the initial stage of hydrolysis, was detected. When xylooligosaccharides from tetraose to hexaose were hydrolyzed, xylotriose was preferentially accumulated, accompanied with lower xylooligosaccharides than substrates used. In the final stage of reaction, these intermediary products were able to be hydrolyzed to xylose and xylobiose, and the ratio of xylobiose to xylose reached to 1.3_??_1.4. The enzyme possessed the weak activity against xylobiose and converted it into xylose.

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A simple defined medium (named SW-C medium) was proposed previously for a minimal defined medium of Lipomyces starkeyi IAM 4753. The medium consists of glucose, biotin, and the minimum amounts of inorganic salts which were expected to be consumed completely during the entire growth of the cells. But the medium failed to support normal growth of the yeast in the retardation and the stationary phases of growth.
This paper deals with the improvement of the medium to two kinds of defined media by slight modification of the medium composition. The one (named MC medium) was defined to be a simple medium supporting normal growth progress throughout growth period, and the other (named ML medium) was defined to be a medium having a composition suitable for the production of lipids in the yeast cells.
In the first step of the study, modification of the SW-C medium to MC medium was achieved by increasing in NH₄⁺ concentration in the SW-C medium. However, the lipid content of the cells grown in MC medium was very low even at the stationary phase of growth.
In the second step of the study, decrease in the concentration of Zn²⁺ in MC medium was observed to be favorable to increase the lipid content of the yeast in the stationary phase of growth although the level of cell density (total cell number/ml) in the medium decreased. Decrease in concentration of other minor elements, such as Mn²⁺, Cu²⁺, Fe³⁺ also caused decrease in cell density in the stationary phase of growth, but failed in the appreciable increase in lipid content of the cells. A little increase in lipid content of the cells was observed with the increase in Mg²⁺ concentration in the medium. From these results, the composition of ML medium was determined.

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The essential oil from the fruits of Lindera citriodora (Sieb. et Zucc.) Hemsl. has been studied. The essential oil was obtained by steam distillation of the seeds and mesocarps. The constituents of essential oil from the mesocarps were investigated by column chromatography, gas chromatography, infrared, ultraviolet, mass and nuclear magnetic resonance spectrometry. Twenty eight compounds were identified. The each oil from the fruits, which were collected in June, August, and September were compared. In consequence, with the ripeness of fruit, the content of dipentene (limonene) and geraniol in essential oil decrease, on the other hand, those of citronellal and geranial increase.

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Conversion of the analogues of carvone and dihydrocarvone by Pseudomonas ovalis, strain 6-1 was carried out as a series of biochemical reduction of terpenes.
(1) As the analogues of carvone, 2-methyl-2-cyclohexenone, the mixture of (-)-cis- and (-)-trans-carveol, 2-cyclohexenone, (±)-menthenone, (-)-piperitone, (+)-pulegone and 3-methyl-2-cyclohexenone were chosen and the conversion of these compounds was carried out in the medium containing ethanol as a carbon source.
Of these compounds, only 2-methyl-2-cyclohexenone was reduced to the corresponding ketone (2-methylcyclohexanone) and alcohol (2-methylcyclohexanol).
(2) As the analogues of dihydrocarvone, cyclohexanone, 2-methylcyclohexanone, the mixture of trans- and cis-2, 5-dimethylcyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, (±)-isomenthone, (-)-menthone, cyclopentanone and (+)-camphor were chosen and the conversion of these compounds was carried out at the same conditions described in (1).
Except for (±)-isomenthone and (+)-camphor, all compounds tested were reduced to the corresponding alcohols.

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