Combination of TLC and HPLC-MS/MS methods. Approach to a rational quality control of Chinese star anise

In this study, a methodological approach for an effective and reliable quality control of Chinese star anise (Illicium verum Hook. F.) is developed and validated. A combined method of TLC and HPLC-MS/MS was used for differentiation of various Illicium species, especially Chinese and Japanese star anise. Species can be distinguished by their TLC flavonoid pattern. A sensitive and selective HPLC/ESI-MS/MS method was developed for the detection and quantification of lower admixtures of I. anisatum and of further toxic Illicium species at a low concentration range using the sesquiterpene lactone anisatin as a marker. The proposed assay includes a solid-phase extraction cleanup procedure with a high recovery (>90%). Chromatographic separation of anisatin was carried out on a C18 column, followed by MS detection using ESI in negative mode. The precursor/product ion transitions m/z 327 --> 127 (quantifier) and m/z 327 --> 297 (qualifier) were monitored. Statistical evaluation of this multireaction-monitoring procedure reveals good linearity and intra- and interday precision. The limits of detection and quantification are 1.2 and 3.9 microg/kg, respectively.     

Trap modification opens new gates to achieve sustainable coral reef fisheries

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LONG‐TERM LAND USE INFLUENCES SOIL MICROBIAL BIOMASS P AND S,PHOSPHATASE AND ARYLSULFATASE ACTIVITIES,AND S MINERALIZATION IN A BRAZILIAN OXISOL

Land use choices differentially affect soil physical and biological properties. Tillage choices in particular affect soil erosion, the retention of soil organic matter, and the biological activity that organic matter supports. The present study evaluated the consequences of different cropping and tillage systems (undisturbed forest, coffee plantation, conventional, and no‐tillage row cropping) for soil microbial indicators and sulfur mineralization after 24 years of cropping on an Oxisol (Typic Haplorthox) in an experimental area at Londrina, Brazil. Soil samples were taken at 0–5, 5–10, and 10–20 cm depths and evaluated for microbial biomass P and S, S mineralization, and phosphatase and arylsulfatase activities. Land use affected microbial biomass P and S, and enzyme activity at all depths studied. The cultivated sites had lower values of microbial activity than the undisturbed forested site. Although the coffee site was not tilled and had high organic carbon content, there was low microbial activity, probably due to higher soil acidity and Al content. The estimates of pool stock for microbial P and annual P flux through the soil microbial biomass suggest that these pools are large enough to significantly affect plant nutrient availability. The greater microbial biomass and activity under forested and no‐tillage sites may be attributed, at least partially, to higher organic matter content. The soil microbial variables examined proved to be strong indicators of soil sustainability. Copyright © 2013 John Wiley & Sons, Ltd.     

Methane cycling in a drained wetland soil profile

Purpose

Peatlands have an important role in methane cycling in the natural environment. Methane emissions as a result of methanogenesis and methanotrophy in soil are affected by several environmental factors such as temperature, oxygen and groundwater level. The objective of this study was to analyse methane cycling as a function of soil depth.

Materials and methods

In this study, methane cycling and soil organic matter mineralization were investigated in a drained fen grassland area of Ljubljana marsh, Slovenia that has been subjected to reclamation strategies for several centuries. Potential mineralization, methane production and methane oxidation rates were measured in slurry incubation experiments with soil samples from 10 sampling depths of a 1-m profile. In addition, the extent of iron reduction in the soil was determined.

Results and discussion

The potential for methane production was low in the investigated soil profile, even in constantly flooded layers below the water table fluctuations. During anaerobic incubations, the highest accumulated concentrations and production rates of methane were observed in the upper 10-cm layer and the lowest in deeper soil layers, indicating that plant exudates are the main source of energy for heterotrophic soil microbes and that methanogenesis in deeper layers is limited by the availability of appropriate organic substrates. Methane oxidation was on the other hand active throughout the soil profile, suggesting that the potentially active methane oxidizing community is present despite low methane production. The highest abundance and activity of methanotrophs was detected in the water table fluctuation layers.

Conclusions

Together, these findings have implications for understanding the biogeochemical function of drained peat soils and emphasize the influence of drainage on quality of soil organic matter and consequently on methane production even in flooded soils.

     

Combination of phytase and citric acid,but not phytase alone,ensures regular rates of growth and bone mineralization in quails under severe phosphorus restriction

An experiment was conducted to evaluate the effects of phytase (PHY), alone or in combination with citric acid (CA), on growing Japanese quails under moderate and severe phosphorus (P) restriction. For this, 504 one‐day‐old female quails were distributed in a completely randomised design with seven treatments and six replications. Treatments consisted of the following diets: (a) positive control (PC): formulated according to quails nutritional requirements; (b) negative control 40% (NC₄₀): PC with 40% less aP; (c) NC₄₀+PHY; (d) NC₄₀+PHY+CA; (e) negative control 65% (NC₆₅): PC with 65% less aP; (f) NC₆₅+PHY; (g) NC₆₅+PHY+CA. Phytase and CA were included at 300 FTU/kg and 40 g/kg, respectively. Performance, bone mineralization and plasma mineral concentration were evaluated at day 35; calcium (Ca) and P metabolism, between days 36 and 39. No significant differences in performance, plasma Ca and P were detected between quails fed PC or NC₄₀; however, NC₄₀ decreased tibia ash (p < 0.01). Treatment NC₆₅ impaired daily weight gain (p = 0.01), tibia ash (p < 0.01), and tibia optical densitometry (p = 0.03), as well as modified plasma Ca (p < 0.01) and P (p = 0.03) concentrations when compared to PC. Both NC₄₀ and NC₆₅ reduced P excretion (p < 0.01). Phytase alone restored tibia ash of NC₄₀ quails to regular rates. Nevertheless, only PHY and CA combined returned plasma P, tibia ash, tibia optical densitometry, and daily weight gain of quails fed NC₆₅ to similar values as those observed in PC. In conclusion, PHY alone suppresses the negative effects of moderate P restriction in growing Japanese quails, but fails in this task under severe P restriction. In such a situation, only the combination of PHY and CA ensures regular rates of growth and bone mineralization. This concept should be better explored by producers in order to take full advantage of the reduction in P excretion achieved by lowering dietary P concentrations.     

Development of the Bovine Duodenum with Reference to Enterochromaffin cells

The present light microscopic study describes the morphological changes which occur in the duodenal mucosa of the bovine fetus from the third month of gestation until birth with regard to the sequence of appearance and morphology of enterochromaffin cells. The mucosa of the duodenum is prepared for digestive activity during the first months of development. This becomes obvious in the early differentiation of the fetal intestinal mucosa. The enterocytes in villus epithelium contain glycogen in the early months. These glycogen pools seem to shrink during the following months. They may provide a metabolic reserve for the fetus, which derives all of its nutrition from carbohydrates. Enterochromaffin cells appear in the three month old bovine fetus with two cell-types situated in the epithelial lining of crypts and villi. The density of enterochromaffin cells increases during gestation. There were no findings to indicate that the fetal enterochromaffin cells did not originate from endoderm. The early appearance from enterochromaffin cells (which are the producers of serotonin, 5-hydroxytryptamine) correlates with first gastrointestinal movements, which are known to commence in the first third of gestation, leading us to believe that 5-HT represents the chemical inducer of muscular motility in the developing intestine.     

2008霉菌毒素普查项目报告

黄曲霉毒素B1、玉米赤霉烯酮、呕吐毒素、烟曲霉毒素、赭曲霉毒素A以及T-2毒素,这些霉菌毒素名称无疑会引起你的警惕。它们是在畜牧生产中最常见、最重要的几种霉菌毒素。尽管这些霉菌毒素是在作物生产周期的不同阶段产生的,但它们都会污染农业产品,并由此而造成动物饲料受到污染。比如玉米赤霉烯酮、烟曲霉毒素和单端孢菌霉烯毒素（呕吐毒素和T-2毒素）等镰刀霉菌毒素主要在田间产生而黄曲霉毒素B1和赭曲霉毒素主要是收获后因不良仓储条件而产生。采食这些有毒的物质导致动物的生产性能和健康受到损害。一些国际上的执法机构,如美国食品和药品管理局（FDA）、Eu ropean Commission Directorate General for Health and Consumers（DG San co）,Food Commission of Mercosur,澳大利亚新西兰食品管理局和南非医学研究委员会等经常参加霉菌毒素主题的研讨会,这说明他们对这一问题有清楚的认识,并且正在研究最佳的处理对策。饲料工业内对霉菌毒素的存在持怀疑态度的人数在逐步减少,现在唯一需要搞清楚的是“问题有多严重？”,或者说是“我们的动物采食的饲料中有多少种及多少含量的霉菌毒素？”。百奥明（BIOMIN GmbH）是一个霉菌毒素风险控制领域的先锋公司,经常为饲料工业同仁提供关于这些问题的答案。下面是百奥明公司提供的一份2008年度霉菌毒素调查报告。