The maximum leaf surface temperatures of the higher plants observed in the Inland Sea area

The maximum leaf surface temperatures (MLSTs) of 126 species of higher plants were measured by means of an infrared thermometer, in the Inland Sea area, southwest of Honshu-Island, Japan, where plants suffered from severe environmental conditions due to an abnormally small amount of precipitation during the summer of 1978. The MLSTs of plants in the summer of 1978 were greater than or equal to those of 1979, when the environmental conditions were not so severe. The MLST measured in this study was 50.4 C for a non-succulent plant (Liriodendron), and 53.1 C for a succulent plant (Agave). Plants with different life forms appeared to have different MLSTs. The average of the MLSTs of conifers deciduous trees, and evergreens were 36.4, 37.7, and 40.3 C, respectively. This order corresponds to the distribution of forests from high to low, latitudes. Also the MLSTs were higher for woody plants than for herbaceous plants. Relatively high leaf temperatures were observed for climbing plants, both herbaceous and woody. Plants with narrow leaves had lower leaf surface temperatures than those with borad leaves. Herbaceous dicotyledonous plants actively growing at the end of the summer of 1978, in full sun at Hiroshima Castle were exclusively those with relatively high leaf temperatures.     

Sophorolipids from Torulopsis bombicola as microbial surfactants in alkane fermentations

The possible role of sophorolipids from Torulopsis bombicola was investigated in alkane fermentation. Sophorolipids and related model compounds specifically stimulated the growth of strains of Torulopsis yeasts on insoluble alkanes and may act as a specific growth factor. There may be more than one way for a yeast to be stimulated to incorporate alkanes for growth.     

Topographic examination of sister chromatid differential staining by nomarski interference microscopy and scanning electron microscopy

BrdU-substituted Chinese hamster chromosomes were treated with a hot Na₂HPO₄ solution and stained with Giemsa to produce sister chromatid differential staining (SCD). The process of SCD was examined with the Nomarski differential interference microscope and the scanning electron microscope. After the Na₂HPO₄ treatment alone, unifilarly BrdU-substituted (TB) chromatids appeared somewhat more severely collapsed than the bifilarly substituted (BB) chromatids. Subsequent Giemsa staining, however, brought about pronounced piling up of the Giemsa dye on the TB-chromatids but not on the BB-ones, causing highly distinct differential Giemsa staining as well as a marked differentiation in surface topography between the sister chromatids. Removal of the Giemsa dye from the differentially Giemsa stained chromosomes resulted in a disappearance of such a pronounced topographic differentiation.     

Two opposite types of sister chromatid differential staining in BUdR-substituted chromosomes using tetrasodium salt of EDTA

The direct staining of BUdR-substituted Chinese hamster chromosomes in a 4Na-EDTA-Giemsa solution resulted in a B-dark type of sister chromatid differential staining (SCD) in which bifilarly substituted chromatids stained dark. On the other hand, when BUdR-substituted chromosomes were pretreated with a 4Na-EDTA solution and then stained with Giemsa, a B-light type SCD was obtained in which bifilarly substituted chromatids stained light.     

Entrapment of microbial cells and organelles with hydrophilic urethane prepolymers

Summary Microbial cells and cellular organelles were immobilized by mixing aqueous suspensions of the biocatalysts with water-miscible urethane prepolymers. Thus immobilized preparations of acetone-dried cells of Arthrobacter simplex and thawed cells of Nocardia rhodocrous showed appreciable {ie351-1} activities in the transformation of hydrocortisone into prednisolone and 4-androstene-3,17-dione to androst-1,4-diene-3,17-dione, respectively. The activities of catalase and alcohol oxidase were observed in the immobilized peroxisomes (microbodies) of a methanol-grown yeast Kloeckera sp. No. 2201. Yeast mitochondria entrapped with the prepolymer showed adenylate kinase activity. These results indicate the usefulness of the urethane prepolymers as convenient materials for entrapment of not only enzymes, but also organelles and microbial cells.     

Action of sweet-potato beta-amylase on phosphodextrin of potato starch

The specificity of sweet-potato beta-amylase in the vicinity of the phosphate ester groups was studied by determining the structures of the phosphorylated oligosaccharides (alpha-phosphodextrin and beta-limit-alpha-phosphodextrin) formed by its action on potato starch. The beta-limit-alpha-phosphodextrin was separated by chromatography on Dowex-1 (HCOO^?) resin into three fractions that were distinguishable by the d.p. and by the ratio of d-glucose 6-phosphate residues to total organic phosphate. Each fraction contained linear molecules having one phosphate ester group that was not located at the reducing or non-reducing terminals. The smallest phosphodextrin was 6²-phosphorylmaltotriose. It was deduced that beta-amylase hydrolysed (1→4)-α-d linkages from the non-reducing end until one or two d-glucosyl residues remained attached to the phosphorylated residue, depending on whether there was originally an odd or even number of glucosyl residues on the non-reducing side of the phosphorylated residue.     

Counteracting effect of eosin and related dyestuffs on the production of respiration-deficient mutants in yeast by 4-nitroquinoline 1-oxide

Production of respiration-deficient (rho^?) mutants under growing conditions in a strain of Saccharomyces chevalieri by 4-nitroquinoline 1-oxide (4NQO), a potent carcinogen, reached 100%. the mutation frequency was considerably reduced when eosin Y was applied in various combinations with 4NQO. The counteracting effect was slight when eosin Y was applied concurrently with 4NQO, but was very strong adn persistent when eosin Y was impregnated into the yeast cells before their exposure to 4NQO. Eosin B, erythrosin B and uranin also showed more or less counteracting effects against 4 NQO in producing the rho^? mutants. Possible mechanisms for the counteracting effects of these dyestuffs against 4NQO are discussed in relation to antimutagenesis and chemotherapeutic interference.     

Studies of oligosaccharide linkages by simultaneous determination of component aldehydes in dialdehyde fragments as (2,4-dinitrophenyl)hydrazones

The component aldehydes in dialdehyde fragments formed by periodate oxidation of oligosaccharides were converted quantitatively into the corresponding (2,4-dinitrophenyl)hydrazones by the simple procedure of treatment with excess (2,4-dinitrophenyl)hydrazine hydrochloride in 1,2-dimethoxyethane. Then, by chromatographic separation of the hydrazones on a small column of silica gel and subsequent spectrophotometric analysis, it was possible to determine the position of glycosidic substitution in μmolar amounts of various types of glucobioses, oligosaccharides of senega, and some synthetic (1→6)-β-D-gluco-oligosaccharides.