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Tabanus bivittatus Mats., a traditional Chinese medicine, is commonly used for cardiovascular disorders treatment including atherosclerosis. There have been only a few researches on its chemical components, and no detailed report has appeared on its fatty acids. To develop a simple and effective method for the extraction of total fatty acids from Tabanus bivittatus Mats., the Soxhlet extraction (SE) condition was optimized with response surface methodology. The fatty acid composition of the extract were determined by GC-MS with previous derivatization to fatty acid methyl esters (FAMEs). The major fatty acids in Tabanus bivittatus Mats. were oleic acid, palmitic acid, linoleic acid, palmitoleic acid, and stearic acid, and the unsaturated fatty acids occupy 63.9% of the total fatty acids.

Soil health is closely related to the soil mite community.Land use types can alter the soil environment,which could further influence soil biodiversity,including that of soil mites.Soil mites are important indicators of soil condition and anthropogenic impact.In order to explore the relationship between soil mites and agricultural land use types,an experiment was conducted in a traditional agricultural region of north China.Four treatments were included: a routine winter wheat-summer maize rotation field,a one-year vegetable plastic greenhouse,a four-year vegetable greenhouse and a four-year open vegetable field.Each treatment was replicated three times.In May and October 2012,the soils were sampled to evaluate the changes in soil physico-chemical parameters as well as the abundance,diversity and community structure of the soil mites.Mite diversity was tested using the Shannon-Wiener index and taxonomic richness,and a canonical correspondence analysis(CCA) was used to elucidate the relationship between the soil mite community,the soil physico-chemical parameters and the treatments.The results indicated that the open vegetable field significantly increased the hydrolyzable nitrogen content and the four-year vegetable greenhouse increased the available phosphorus content.The average mite abundances from each plot were 22568 ind/m2 in May and 20155 ind/m2 in October.A total of thirty-six soil mite taxon groups were identified.Acaridae were the most abundant at 39%.Other dominant mite taxa included Tarsonemidae,Pygmephoridae,Microdispidae,Laelapidae,Ascidae,Mesostigmata nymph,Scheloribates sp.,Tectocepheus velatu,Oppiella sp.,Oppia sp.1,Protoribates sp.and oribatid juveniles.These dominant taxa accounted for 91% of mite abundances.The soil mite community analysis showed that Oribatid mites were dominant in the routine agricultural field.From the routine field to the greenhouse,the r-strategic Astigmata,especially the Acaridae,became the dominant assemblage over the K-strategic oribatid mites,which could be attributed to the increase in fertilizer input and human disturbance.The succession was obvious in the new built one-year vegetable greenhouse treatment.However,the mite diversity and Acaridae abundance decreased after the greenhouses were used for four years,which suggested that the accumulation of phosphorus and the more frequent disturbance were unfavorable conditions for the soil mite community.Disturbance also decreased the abundance of Oribatida,Pygmephoridae and Microdispidae.From the routine field to the open vegetable field,management led to a decrease of Oribatida with the four suborders having a similar proportion in the open vegetable field.Compared with the vegetable greenhouses,the open vegetable field had a more equable distribution of the four treatments.In summary,the most serious disturbance and the highest loss of mite diversity occurred in the vegetable greenhouses,compared with the other two land use types.This loss of mite diversity could destroy soil fertility maintenance and self-restoration and have a negative impact on sustainable agricultural productivity.Therefore,although greenhouses can increase yield and income,we should pay more attention to the protection of soil biodiversity in future,especially of the mite community.

This study was aimed to optimize the extraction process for Salvia miltiorrhiza Bunge polysaccharide using response surface methodology The results showed that four operating parameters including microwave power, microwave time and the particle size had notable effects on the polysaccharide extraction of Salvia miltiorrhiza Bunge. The effects could be ranked in decreasing order of importance as follows:. Microwave power > microwave time > the comminution degree. The optimal extraction parameters were determined as 573.83W of Microwave power and 8.4min of microwave time and 67.51mesh of the comminution degree, resulting in the yield of Salvia miltiorrhiza Bunge polysaccharide of 101.161mg / g. The established regression model describing polysaccharide extraction from as a function of the three extraction parameters was highly significant (R 2 = 0.9953). The predicted and experimental results were found to be in good agreement. Thus, the model can be applicable for the prediction of polysaccharide extraction from Salvia miltiorrhiza Bunge.