Separation and Purification of Molecular Species of Galactolipids by High Performance Liquid Chromatography

The NaCl concentration of the growth medium affected hydrogen production by Lyngbya sp. (No. 108) strain. Cells grown in medium containing 3% NaCl produced the most hydrogen. The carbohydrate content of this strain also increased with increasing NaCl concentration of the growth medium up to 720 fig/mg cells at 5 % NaCl. In the presence of 20 finlol/ml MFA (monofluoroacetic acid), inhibition of hydrogen production was observed. We extracted the glycogen from this nonheterocystous filamentous cyanobacterium, Lyngbya sp. (No. 108), and observed that glycogen and carbohydrate consumption of this strain is coincident with hydrogen production.

These results led us to the conclusion that the reserve glycogen or other carbohydrate were used as sources of electron donors for hydrogen production, and that the NaCl concentration of the medium affected the hydrogen production by this strain.     

Studies on Oxygen Transfer in Submerged Fermentations

The unsteady-state gas analysis method for the determination of oxygen transfer rate in shaken cultures was applied to the glutamic acid fermentation. This method was essentially based on the measurement of oxygen tension of gas phase in flasks. Major intentions of this application were to clarify the problems of oxygen transfer, to establish the measure of aeration effectiveness and to design the best aeration condition in the glutamic acid fermentation. Correlations of the fermentation to the level of dissolved oxygen, the rate of oxygen transfer, overall oxygen transfer coefficient and oxygen demand of cells were examined. As a measure of aeration effectiveness, the rate of oxygen transfer actually occurring in the fermentation seemed to be preferable, and was found to be above 7 × 10^?7 mol/ml-min for attaining the maximum productivity. Extremely high or low oxygen supply resulted in less productivity.     

Epiderstatin and Its Related Glutarimide Antibiotics Inhibit the Cell Growth Induced by Mitogen Stimulation

To investigate the immunosuppressive effects of glutarimide antibiotics including a new antibiotic named epiderstatin, we tested these antibiotics for inhibition of the blastogenesis of mouse spleen cells induced by mitogen stimulation (concanavalin A or lipopolysaccharide). The inhibitory activity was measured by colorimetric MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay. Among the glutarimide antibiotics tested, epiderstatin and acetoxycycloheximide especially strongly inhibited the blastogenesis of mouse spleen cells induced by concanavalin A and lipopolysaccharide, however, selectivity between T and B lymphocytes was not observed.     

Solid State 13C-NMR Analysis of Cell Wall Components of Fusarium oxysporum

An abdominal fat accumulation complicated by high blood triglycerides is regarded as a risk factor of metabolic syndrome. Feeding powdered nacre, mother of pearl, from Pinctada maxima, resulted in reduced body weight, visceral fat amount, and blood triglyceride level without influencing the food intake, body length, or amount of muscular tissue, suggesting that nacre powder specifically could decrease visceral fat.     

Conformation of Some Hexuronic Acids and d-Galactopyranosiduronic Acid Moiety in the Peracetylated and Permethylated Derivatives of Orange Pectic Acid in Solutions

1. The 1C conformation was estimated for α-d-galactopyranosiduronic acid moiety of pectic acid in the permethylated derivative dissolved in 1 n NaOD-D₂O and in the peracetylated derivative dissolved in dimethyl sulfoxide-d₆, and the C1 conformation was estimated for some derivatives of d-galactopyranuronic acid in chloroform-d by NMR spectroscopy.

2. Random conformation of the whole macromolecule was estimated for pectic acid in water on the basis of no appearance of any induced Cotton effects in the 200 ~ 700 mμ region in the ORD spectra of pectic acid-anionic dye complexes.

3. The conformation was supported by the fact that the rate of periodate oxidation of pectic acid at 5° was slightly decreased in comparison with that of amylase in 7 m urea solution.

     

Applying Proteolytic Enzymes on Soybean

Soy proteins were incubated with a microbial acid protease (Molsin) under the following condition: substrate concentration, 1%; enzyme-substrate ratio (by weight), 1/100; pH, 2.8; and temperature, 40°C—flavor components and related impurities are removable from crude soy-protein concentrates by their incubation for 2 hr under the above condition. The acid-precipitated fraction of soy protein incubated for 2 hr with Molsin (i.e. 2 hr-proteolyzate) showed the following composition: 10% trichloroacetic acid (TCA) insoluble fraction, 47.52%; 10% TCA soluble peptide fraction, 52.02%; and free amino acid fraction, 0.46%. Gel filtration of the 2 hr-proteolyzate gave an elution pattern showing its molecular weight distribution.

In the process of the incubation of the acid-precipitated protein, the 10% TCA insoluble fraction showed increase in amino nitrogen content, its solubility in a phosphate buffer increased to change at 6 hr, and a hydrophobic amino acid share in this fraction increased gradually.

In vitro digestibility of the acid-precipitated fraction were improved and the lipoxygenase activity in this fraction decreased through the Molsin treatment.

Ultracentrifugal analysis showed a decreasing tendency of the cold-insoluble fraction of soy protein during its incubation with Molsin. Optical rotatory dispersion and circular dichroism study elucidated conformational changes in this fraction during its incubation either with or without Molsin.     

Stimulation of Methionine Sulfoxide Reduction and Ethylene Production by Isoprothiolane in Relation to Its Activity against Non-parasitic Damping-off (MURENAE Disease) of Rice Seedlings

A rice blast controlling agent, isoprothiolane (diisopropyl 1,3-dithiolan-2-ylidenemalonate), stimulated the reduction of methionine sulfoxide to methionine by the rice plant. In the presence of isoprothiolane, the methionine/(methionine + its sulfoxide) ratio was increased to 129~208% of the control. The ethylene production by the plant was also enhanced by isoprothiolane, probably because methionine is an important precursor of ethylene. The non-parasitic damping-off caused by chilling stress on rice seedlings was effectively prevented with the application of isoprothiolane as well as ethephon, which easily decomposes to ethylene and acids. Therefore, the ethylene level modified by isoprothiolane and ethephon can contribute to their protective activity against the non-parasitic damping-off of rice seedlings. Indeed, a close relationship between the ethylene level and the protective activity against damping-off was obtained with isoprothiolane, but not with ethephon. Endogenous ethylene seems to be more effective in controlling the damping-off than exogenous ethylene from ethephon.     

Excessive Cytokine Response to Rapid Proliferation of Highly Pathogenic Avian Influenza Viruses Leads to Fatal Systemic Capillary Leakage in Chickens

Highly pathogenic avian influenza viruses (HPAIVs) cause lethal infection in chickens. Severe cases of HPAIV infections have been also reported in mammals, including humans. In both mammals and birds, the relationship between host cytokine response to the infection with HPAIVs and lethal outcome has not been well understood. In the present study, the highly pathogenic avian influenza viruses A/turkey/Italy/4580/1999 (H7N1) (Ty/Italy) and A/chicken/Netherlands/2586/2003 (H7N7) (Ck/NL) and the low pathogenic avian influenza virus (LPAIV) A/chicken/Ibaraki/1/2005 (H5N2) (Ck/Ibaraki) were intranasally inoculated into chickens. Ty/Italy replicated more extensively than Ck/NL in systemic tissues of the chickens, especially in the brain, and induced excessive mRNA expression of inflammatory and antiviral cytokines (IFN-γ, IL-1β, IL-6, and IFN-α) in proportion to its proliferation. Using in situ hybridization, IL-6 mRNA was detected mainly in microglial nodules in the brain of the chickens infected with Ty/Italy. Capillary leakage assessed by Evans blue staining was observed in multiple organs, especially in the brains of the chickens infected with Ty/Italy, and was not observed in those infected with Ck/NL. In contrast, LPAIV caused only local infection in the chickens, with neither apparent cytokine expression nor capillary leakage in any tissue of the chickens. The present results indicate that an excessive cytokine response is induced by rapid and extensive proliferation of HPAIV and causes fatal multiple organ failure in chickens.     

Glutathione maintenance is crucial for survival of melanocytes after exposure to rhododendrol

Rhododendrol is a phenolic compound that shows a tyrosinase‐dependent toxicity for melanocytes and occasionally induces a vitiligo‐like skin depigmentation. The post‐tyrosinase mechanisms determining melanocyte death or survival, however, are far from clear. Here, we find that rhododendrol treatment leads to a reduction in the levels of cellular glutathione but also induces a cellular antioxidant response that eventually increases glutathione levels. We further find that rhododendrol toxicity is enhanced when glutathione levels are experimentally reduced and alleviated when glutathione levels are increased. Hence, it appears that the size of the preexisting glutathione pool along with the capacity to supply glutathione via the antioxidant response determines whether melanocytes survive or die after rhododendrol exposure. It is conceivable, therefore, that rhododendrol‐induced leukoderma depends on the capacity to maintain appropriate glutathione levels and that enhancement of glutathione levels may preserve a patient's melanocytes and potentially help in repigmentation.