Moisture influence on fungal growth in black pepper

The moisture content at which fungal growth proliferated on black pepper was determined at different relative humidities. At 18% moisture content, fungal growth occurred but this was not recorded at the next lower moisture content of 13.9%. Microscopic examination of infected fresh green pepper showed the presence of species of Trichothecium, Colletotrichum and Fusarium. In black pepper, species of Aspergilli and Penicillium were observed.     

INHIBITION OF SHIKIMATE DEHYDROGENASE FROM HEART-OF-PALM (EUTERPE OLERACEA MART.)

Shikimate dehydrogenase (E.C.1.1.1.25), extracted from heart-of-palm, was purified by precipitation with ammonium sulphate and elution from columns of Sephadex G-25, and DEAE-Sephadex A-50. The enzyme was unstable and it was not possible to maintain the activity by the addition of cysteine and 2-mercaptoethanol to the buffer. The heart-of-palm contained two isoenzymes which were separated by polyacrylamide gel electrophoresis. The enzyme was inhibited by metal ions and p-CMB. The p-CMB inhibition was reversed by cysteine. The shikimate dehydrogenase was competitively inhibited by protocatechuic acid (Ki 7.5 × 10^?4M), and Km values of 0.021 mM and 0.011 mM for shikimic acid and NADP⁺, respectively, were obtained at pH 9.5 in Tris-HCl-glycine buffer. The molecular weight determination was performed on Sephadex G-100 and the MW was estimated to be 50,000 daltons.     

The influence of preparation conditions on the electrochemical behaviour of CuO in a Li/CuO cell

A dozen CuO samples prepared under various conditions and from different starting materials were evaluated as cathode materials for a primary Li/CuO cell. The “thin electrode” method was used for rapid evaluation of the samples. Both coulombic efficiency and discharge voltage depend considerably on the method of synthesis. No correlation was found between the specific surface area and the resistivity of the samples on the one hand and the cathode performance on the other. Best results were obtained from CuO prepared by the oxidation of Cu₂O under controlled temperature and time of oxidation.     

Temperature resistance coefficient of composite resistive materials in the mixed-structure approximation

A method of calculating the temperature resistance coefficient and its temperature dependence for resistive materials in the approximation of a matrix-statistical structure is outlined.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 3, pp. 477–481, September, 1985.     

Non-specific antitumoral activity of staphylococcal enterotoxins

St. aureus enterotoxins A and B possess an antitumour effect. After intraperitoneal inoculation they decrease the size and in some cases prevent the development of the human hypernephroma in the cheek pouch of golden hamsters. The effect of enterotoxins may possibly consist in inducing the production of endogenous immune interferon which activates the host immune system and enhances the rejection of heterologous tumour cells.     

Close interaction of coplanar circular cracks under shear loading

A new method is proposed for the stress analysis of an elastic space weakened by several arbitrarily located coplanar circular cracks subjected to an arbitrary shear loading. The method is based on a new type of integral equation and has definite advantages over the existing methods: equations are non-singular, the iteration procedure is rapidly convergent even for very close interactions. The method allows us to obtain a practically exact numerical solution to the problem of very close interactions. An accurate analytical solution is obtained for the case of two cracks, which are separated by a half of their radius or more. The stress intensity factors and the crack energy increase due to the interaction are computed for various distances between the cracks.The reported research was supported by a grant from the Natural Sciences and Engineering Research Council of Canada     

Selenium in Foods Produced and Consumed in Greece

The total selenium within a wide variety (315 food items) of Greek foods was determined fluorimetrically. Rich selenium sources were the proteinaceous foods such as fish, meat, bread, and spaghetti. Butter, oils, vegetables, and fruits were poor sources. The selenium content of Greek foods was lower than that of many other countries and resembled more closely that of British foods. From available food consumption data and values in this study, it was estimated that the daily selenium intake of Greeks was 110 μg.     

Dynamics of the uptake of free amino acids in the blood serum of the portal vein during the digestion of isolated krill protein

The rate of absorption of amino acids obtained from isolated krill protein administered to rat stomach was studied. Absorption of casein amino acids was determined for reference purposes. Rats subjected to 48-hour fasting were administered krill isolate and casein in the form of homogenates at a rate 540 mg protein per 100 g bw in 6 ml of distilled water. The concentration of free amino acids in the portal vein was measured after 30 minutes, 1, 3 and 6 hours. The content of amino acids was measured by ion-exchange chromatography with the use of an automatic analyzer of amino acids. The digestion of krill protein proceeds at a high rate. This ensures the maximal augmentation of the concentration of most amino acids in the blood of the portal vein 30 min after isolate administration to the stomach.