The Role of Chloride Channels and Chloride Ions in Regulation of Steroidogenesis in the Gonads of Amphibians,Birds, and Mammals

The paper represents the first review of data on the involvement of chloride channels (their inhibitors and media, in which chloride ions are substituted for anions that poorly penetrate in the cell) in the regulation of basal and gonadotropin-stimulated steroidogenesis in the gonads of amphibians, birds, and mammals. Possible causes are considered for different reactions of the gonad steroidogenic cells in representatives of different vertebrate classes to a decreased medium concentration of chloride and the involvement of chloride channels and/or chloride ions in the regulation of steroidogenesis is discussed.     

Effect of soil amendement with root extract ofhibiscus cannabinus L. on its rhizosphere mycoflora

Summary Rhizosphere mycoflora ofH. cannabinus was studied in potted condition after its root extract obtained from two month old plants. Isolations of fungi from the root regions were done at the interval of 15 days by dilution plate method. Estimation of fungi/g dry soil showed a negative rhizosphere effect. A higher number of fungal species was recorded in the treated non-rhizosphere as compared to their number in the rhizosphere. Qalitative analysis of the fungal flora was done and the variation was recorded. Root extract was analysed by paper chromatography. Altogether 7 amino acids and 3 sugars were detected.     

Technical Communication: Evaluation of cassava extract/soya bean digest medium for fungal growth

A medium that is cheaper than commercial media but just as good for assessing growth and viability of yeasts and fungi has been formulated using local ingredients: cassava and soya beans.The author is with the Department of Microbiology, Faculty of Science, University of Benin, Benin City, Nigeria.     

酵母菌体在食品中开发与应用

介绍以酵母菌体为原料制取食用蛋白、酵母精及增鲜剂，并对各制品在食品中的应用进行了阐述，旨在推动酵母菌体开发与利用的进程。     

Ginkgo biloba extract protects rat kidney from diabetic and hypoxic damage

Ginkgo biloba extract EGb 761 was studied for its nephroprotective effects in experimentally diabetic and hypoxic rats. Duration of streptozotocin-induced diabetes was 4 months, that of respiratoric hypoxia of the diabetic group 20 min. The daily dose of 100 mg EGb/kg bodyweight started 1 month after induction of the diabetes. EGb reduced diabetes-induced morphological alterations of the kidney such as increase in volume of glomeruli, capillary tufts, urinary space, and thickening of Bowman's capsule basement membrane. Diabetically increased immunostaining of interstitial collagenes of types I, III, and VI was diminished by the EGb extract. EGb reduced the relative total SOD activity from 163% in diabetic kidney to 46%. Additional hypoxia-induced ultrastructural damage was also diminished.     

A validated liquid chromatography–electrospray ionization–mass spectrometry method for quantification of spilanthol in Spilanthes acmella (L.) Murr.

Introduction – The medicinal plant Spilanthes acmella (L.) Murr. has demonstrated an array of biological activities that are generally attributed to the presence of spilanthol and other alkylamides. Recently this plant has been of interest due to its potential for the treatment and prevention of malaria. Objective – The aim of this study was to develop a liquid chromatography–electrospray ionisation–mass spectrometry (HPLC‐esiMS) method for rapid identification and quantification of the alkylamide spilanthol from S. acmella. Methodology – Hydroethanolic extracts were prepared from fresh S. acmella using different percentages of ethanol and were stored at ?80, ?20 and 25°C. Spilanthol was isolated and used as a standard for quantitative analysis. Results – Validation parameters for the HPLC‐esiMS analysis of spilanthol were as follows: repeatability, ≤6%; intermediate precision, ≤2%; range, 0.45–450 µm ; limit of detection, 0.27 µm ; and limit of quantification, 0.45 µm . Eight alkylamides in the S. acmella extract were identified based on MS‐MS fragmentation patterns, and NMR analysis confirmed the identity of the most abundant of these as spilanthol. Spilanthol was extracted most efficiently in solvents containing >75% ethanol, and was stable in ethanolic extracts stored at all three temperatures. Conclusion – These results demonstrate the effectiveness of HPLC‐esiMS for quantitative and qualitative analysis of spilanthol. We show that spilanthol is effectively extracted in ethanol, and is stable in ethanol extracts for over 6 months, even at room temperature. Copyright © 2010 John Wiley & Sons, Ltd.     

Grape seed extract enhances eNOS expression and NO production through regulating calcium‐mediated AKT phosphorylation in H2O2‐treated endothelium

GSE (grape seed extract) has been shown to exhibit protective effects against cardiovascular events and atherosclerosis, although the underlying molecular mechanisms of action are unknown. Herein, we assessed the ability of GSE to enhance eNOS (endothelial nitric oxide synthase) expression and NO (nitric oxide) production in H₂O₂ (hydrogen peroxide)‐treated HUVECs (human umbilical vein endothelial cells). GSE enhanced eNOS expression and NO release in H₂O₂‐treated cells in a dose‐dependent manner. GSE inhibited intracellular ROS (reactive oxygen species) and reduced intracellular calcium in a dose‐dependent manner in H₂O₂‐treated cells, as shown by confocal microscopy. ROS was inhibited in cells pretreated with 5.0 μM GSE, 2.0 μM TG (thapsigargin) and 20.0 μM 2‐APB (2‐aminoethoxydiphenyl borate) instead of 0.25 μM extracellular calcium. In addition, GSE enhanced eNOS expression and reduced ROS production via increasing p‐AKT (AKT phosphorylation) with high extracellular calcium (13 mM). In conclusion, GSE protected against endothelial injury by up‐regulation of eNOS and NO expression via inhibiting InsP₃Rs (inositol 1,4,5‐trisphosphate receptors)‐mediated intracellular excessive calcium release and by activating p‐AKT in endothelial cells.     

Metarhizium anisopliae conidial responses to lipids from tick cuticle and tick mammalian host surface

Conidial germination and the formation of appressoria are important events in the interactions between entomopathogenic fungi and their arthropod hosts. In this study, we demonstrate the effects of lipids extracted from tick epicuticle and the surface of a mammalian host (calf) on conidial germination and the development of appressoria in two subspecies of Metarhizium anisopliae, M. anisopliae var. anisopliae (M.an.an.-7) and M. anisopliae var. acridum (M.an.ac.-5), which have different levels of virulence toward ticks. Pentane extracts of epicuticles of ticks susceptible and resistant to fungal infection always stimulated the germination of M.an.an.-7 conidia and the development of their appressoria; whereas the effects of dichloromethane (DCM) extracts of tick epicuticle varied depending on the tick. The DCM extracts from most of the tick species and developmental stages stimulated conidial germination and/or the formation of appressoria in M.an.an.-7. However, a DCM extract of lipids from the most resistant tick, engorged Hyalomma excavatum female, inhibited the germination of M.an.an.-7 conidia. Conidia of the non-virulent M.an.ac.-5 did not germinate on agarose amended with any of the examined tick extracts. However, when the tick extracts were placed on bactoagar, conidial germination increased 7- to 8-fold. Extracts from the skin, hair and ear secretions of a calf stimulated conidial germination and the formation of appressoria in M.an.an.-7, but not M.an.ac.-5. This study demonstrates that lipids from tick epicuticles and mammalian skin selectively affect the germination of conidia of entomopathogenic fungi. The effects of these lipids may explain the variability in tick control these fungi provide for different hosts.     

Methyl-β-cyclodextrin restores the structure and function of pulmonary surfactant films impaired by cholesterol

Pulmonary surfactant, a defined mixture of lipids and proteins, imparts very low surface tension to the lung-air interface by forming an incompressible film. In acute respiratory distress syndrome and other respiratory conditions, this function is impaired by a number of factors, among which is an increase of cholesterol in surfactant. The current study shows in vitro that cholesterol can be extracted from surfactant and function subsequently restored to dysfunctional surfactant films in a dose-dependent manner by methyl-β-cyclodextrin (MβCD). Bovine lipid extract surfactant was supplemented with cholesterol to serve as a model of dysfunctional surfactant. Likewise, when cholesterol in a complex with MβCD (“water-soluble cholesterol”) was added in aqueous solution, surfactant films were rendered dysfunctional. Atomic force microscopy showed recovery of function by MβCD is accompanied by the re-establishment of the native film structure of a lipid monolayer with scattered areas of lipid bilayer stacks, whereas dysfunctional films lacked bilayers. The current study expands upon a recent perspective of surfactant inactivation in disease and suggests a potential treatment.     

Fluid bed drying of guarana (Paullinia cupana HBK) extract: Effect of process factors on caffeine content

The aim of this study was to study the convective drying of the hydroalcoholic extracts obtained from powdered guarana seeds in a spouted bed dryer. The influence of process variables, such as the convective airflow rate, extract feed rate, and air inlet temperature, on the quality of the dry extract was determined using the caffeine and moisture content for the process evaluation. The caffeine content in the alcoholic and dried extracts was determined by capillary gas chromatography. The experiments were performed following a 3³ factorial design and the data analyzed by response surface. The analysis of dry extract showed that the air and extract feed rates did not significantly affect (25% level) the caffeine content, but that drying temperature is a major factor to consider when the extract is submitted to fluid bed drying. Caffeine losses were significant (1% level) for drying temperatures above 120°C, while moisture content was lower than 3% for temperatures above 120°C. The data showed that there is an optimum temperature for the drying of guarana extracts in spouted beds, and under the conditions used in this study it was 120°C.