Enzymatic digestion of corncobs pretreated with low strength of sulfuric acid for bioethanol production

In this study, the effect and the optimum pretreatment condition of corncobs using low strength of H₂SO₄ were investigated, in which H₂SO₄ was used to improve the enzymatic digestibility of corncobs for saccharification without degradation of sugars released. The optimum pretreatment condition was found to be the addition of 0.5% (vol./vol.) H₂SO₄ and autoclaving at 122 °C for 20 min. Under this condition, the structural integrity of corncob was altered to make cellulose microfibrils more accessible for cellulase enzymes, and the enzymatic digestion of corncobs could be significantly enhanced. A high yield of sugar, 80% (wt./wt.), could be obtained at a low enzyme dosage of 0.024 g enzymes/g cobs, when pretreated. As a result, the ethanol production was obviously improved by the pretreatment, i.e., the ethanol yield of 77% (wt./wt.) was obtained within 36 h in the SSF fermentation using Saccharomyces cerevisiae NBRC2114.     

Screening of lactic acid bacteria for bile salt hydrolase activity

Bile salt hydrolysis is an important metabolic reaction in the bile salt metabolism of mammals. This reaction has a facilitating effect for bile salt excretion but can also be involved in various illnesses. In recent years interest has increased to use bile salt hydrolysis to influence the cholesterol metabolism of humans and farm animals. To understand the distribution and range of bile salt hydrolase activity in lactic acid bacteria, we screened more than 300 strains of the genera Bifidobacterium and Lactobacillus and the species Lactococcus lactis, Leuconostoc mesenteroides, and Streptococcus thermophilus. Results obtained for 273 strains showed that bile salt hydrolase activity is common in Bifidobacterium and Lactobacillus but absent in L. lactis, Leu. mesenteroides, and S. thermophilus. Nearly all bifidobacteria species and strains have bile salt hydrolase activity, whereas this activity can only be found in selected species of lactobacilli. A strong correlation can be observed between the habitat of a genus or species and the presence of bile salt hydrolase activity. Most often bile salt hydrolase activity is found in strains that have been isolated from the intestines or from feces from mammals--an environment rich in conjugated and unconjugated bile acids. Strains and species from other habitats like milk or vegetables--environments from which bile salts are absent--do normally not have bile salt hydrolase activity. In two independent assays, we established that bile salt hydrolase activity in bifidobacteria is, in general, much higher than in lactobacilli.     

Jamaican vomiting sickness. Biochemical investigation of two cases

We identified methylenecyclopropylacetic acid, a known metabolite of hypoglycin A, in the urine of two patients with Jamaican vomiting sickness. Excretion of unusual dicarboxylic acids such as 2-ethylmalonic, 2-methylsuccinic, glutaric, adipic and dicarboxylic acids with eight and 10 carbon chains were also detected in both patients. The amounts of these dicarboxylic acids were 70 to 1000 times higher than normal. These metabolites have also been identified in urine of hypoglycin-treated rats. This evidence links hypoglycin A to Jamaican vomiting sickness as its causative agent. Urinary excretion of short-chain fatty acids was also increased up to 300 times higher than normal. These results indicate that, despite their clinical and histologic similarities, the cause and biochemical mechanisms of Jamaican vomiting sickness differ distinctly from those of Reye's syndrome in which these abnormal urinary metabolites are not appreciably increased.     

Non-African Burkitt's lymphoma in a young woman

Non-African Burkitt's lymphoma is presented in a 29-year-old, unmarried woman, who developed tumors in both breats and ovaries, ascites and pleural effusion. Assessment of B cells in the tumor cells, derived from ascites, pleural effusion and tumor tissue is 90%, surface IgM being consisted of 86%, in an average. Histologically, the tumor tissue demonstrates prominent, socalled starry-sky effect, and cytologically, tumor cells are poorly-differentiated lymphocytoid cells in their feautures.     

The influence of nephrectomy, ureteral ligation, and of estradiol on plasma renin substrate in unilaterally nephrectomized rats

The effects of three experimental conditions on the concentration of plasma renin substrate were studied with special reference to plasma renin concentration in unilaterally nephrectomized rats. After simultaneous bilateral nephrectomy the maximum increase in plasma renin substrate was 17 times higher than normal within 24 h, while in rats which were unilaterally nephrectomized 10 days previously, followed by the removal of the remaining kidney (two-step bilateral nephrectomy), the maximum increase in plasma renin substrate was markedly suppressed (6-fold of normal). The maximum increases in plasma renin substrate by estradiol treatment in normal and unilaterally nephrectomized rats were about the same, associated with similarly decreased plasma renin concentrations. The similar increase in plasma renin substrate was found after ureteral ligation in unilaterally nephrectomized rats and bilateral ligation of the ureters in normal rats. This was the case where the plasma renin concentrations changed differently after ureteral ligation. After two-step bilateral nephrectomy plus estradiol treatment the maximum increase in plasma renin substrate was found to be higher than that found after two-step bilateral nephrectomy, but was lower than that after simultaneous bilateral nephrectomy. It is suggested that under the pathological conditions that stimulate renin substrate production, the plasma rein substrate concentration is less affected by circulating renin.     

Fatty marrow in the vertebrae. A parameter for hematopoietic activity in the aged

Fatty alteration of bone marrow was analyzed in upper lumbar vertebrae obtained from 94 autopsies. Of these, 85 were from individuals over 60 years of age. Fatty marrows were classified grossly into three groups: Group I, a massive type, Group II, a moderate or less significant type; Group III, a nonfatty type. Fatty marrows of Groups I and II were found most frequently in the older subjects. They were not observed (0/9) below 60 years of age, but were present in 42% (5/12) in the 6th decade, 61% (23/38) in the 7th decade, 76% (25/33) in the 8th decade, and 100% (2/2) in the 9th decade. This may relate to a decreasing volume of a reservoir stem cell compartment for blood cell generation. Since the vertebral marrow is the last reserve site for hematopoietic activity, the volume of fatty marrow in the vertebrae may be used as a parameter for the estimation of hematopoietic activity in the entire skeletal system in the aged.     

Arsenic metabolism. (17) Studies of placental transfer of arsenic and the effects of antidotes and diet

Albino rats of Wistar strain (Tamura 1950) breeded in a closed colony were administered arsenic trioxide orally during pregnancy (from the 0 day to the 20th day). Organs of fetuses and mother rats were exenterated on the 21st day of gestation and the contents of arsenic measured using an arsenic analyzer unit with atomic absorption spectrophotometry. Whole organs of the fetus were separated into 3 groupings i.e. liver, brain and remaining organs. The contents of arsenic in the organs in each of these groupings and in the placenta were measured. Even in the non-administered group, arsenic was detected in the every organ. In the arsenic administered group, the content of arsenic in the placenta was the highest among the four preparations tested; and the content in the liver and remaining organs was considerably high, but was low in the brain. The level of accumulation of arsenic differed between each organ. In the placenta, the accumulation reached a plateau, and in the brain this accumulation was below one-tenth that in the liver. In the non-administered group, arsenic was detected in the liver, kidney, spleen and brain of mother rats. In the group on arsenite, the content in the kidney and spleen was large, followed by a large amount in the liver and in the brain respectively. The level of accumulation of arsenic in mother rats differed between each organ. Arsenite was administered with antidotes such as dimercaprol, thioctic acid and L-ascorbic acid during pregnancy (from the 0 day to the 5th day). In this group the content of arsenic in the remaining organs was statistically less than that of the control group. The content in the brain was slightly reduced by a co-administration of the antidotes, however, there was no statistical difference in the placenta and liver between the antidote-treated and control groups. The content of arsenic in the kidney of mother rats treated with antidotes was statistically less than that of the controls. Whether or not the content of arsenic in organs of fetuses and mother rats was affected by a milk diet was also studied. The content of arsenic in the organs of fetuses showed no statistical difference between the animals on an Oriental stock diet group and those on the milk diet. On the other hand, the content of arsenic in the kidney of mother rats on the milk diet was statistically less than seen in those in the Oriental stock diet group.     

Investigation of the antiviral properties of copper iodide nanoparticles against feline calicivirus

This study demonstrated the antiviral properties of copper iodide (CuI) nanoparticles against the non-enveloped virus feline calicivirus (FCV) as a surrogate for human norovirus. The effect of CuI nanoparticles on FCV infectivity to Crandell-Rees feline kidney (CRFK) cells was elucidated. The infectivity of FCV to CRFK cells was greatly reduced by 7 orders of magnitude at 1000μgml(-1) CuI nanoparticles. At the conditions, electron spin resonance (ESR) analysis proved hydroxyl radical production in CuI nanoparticle suspension. Furthermore, amino acid oxidation in the viral capsid protein of FCV was determined by nanoflow liquid chromatography-mass spectrometric (nano LC-MS) analysis. The use of CuI nanoparticles showed extremely high antiviral activity against FCV. The high antiviral property of CuI nanoparticles was attributed to Cu(+), followed by ROS generation and subsequent capsid protein oxidation. CuI nanoparticles could be proposed as useful sources of a continuous supply of Cu(+) ions for efficient virus inactivation. Furthermore, this study brings new insights into toxic actions of copper iodide nanoparticles against viruses.     

Application of a novel technique for band sawing using a tip-inserted saw regarding surface profiles

One way of achieving a successful forest management leading to biodiversity conservation is to ensure that wood is processed in an efficient manner. The authors succeeded in developing a new technology for bandsawing using a tip-inserted saw. The material used for the tipped edge was High Speed Steel (HSS) of designation SHK 51 according to the Japan Industrial Standard (JIS). The efficiency of the tip-inserted saw was investigated considering its effectiveness in controlling tooth marks and washboarding patterns that sometimes occur during bandsawing. The surface profile of the workpiece generated after sawing with 700 mm and 1100 mm diameter bandmills of the laboratory and industrial type respectively were determined using a CCD laser displacement sensor of scanning length 250 mm and scanning speed of 3 mm/sec at a sampling rate of 50 Hz. Under a setup wheel rotation speed of 200 rpm and feed speed of 1 m/min, washboardings were induced during sawing with the tip-inserted saw of uniform pitch. Thereafter, a tip-inserted saw of random pitch was constructed without removing the saw from the pulley and cutting tests were performed under the same cutting conditions when washboardings were induced during sawing with the uniform pitch tipped-inserted saw. It was observed that the washboarding pattern disappeared completely. Thus the tip-inserted saw of random pitch was very effective in controlling the washboarding pattern. Comparisons of the surface profiles of the workpiece generated by sawing with uniform pitch tip-inserted and stellite-tipped saws under both laboratory and industrial conditions indicate that regardless of the type of bandmill used, the surface profile measured with the laser displacement sensor was smoother for tip-inserted saws than stellite-tipped saws.