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Objective: To establish a HPLC fingerprints evaluation method for Angelica Sinensis Radix (ASR) based on traditional decoction process of Ancient Classical Prescriptions of Traditional Chinese Medicine (ACPTCM). Methods: The fingerprints of 10 batches of ASR were further evaluated by chemometrics methods. The similarity analyzed with “Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine 2004A,” and hierarchical clustering analysis (HCA) and principal component analysis (PCA) were performed by SPSS (version 22.0, SPSS Inc., Chicago, IL, USA). Results: There were 12 common peaks, and the similarity degrees of 10 batches of samples were more than 0.923 and showed that all the samples from different origins were of good consistency. The samples were divided into 4 clusters by HCA. The results of PCA showed that the 3 factors were chosen, the quality of samples could be evaluated basically. The comprehensive score results show that the ASR with Lot.Nos.DG-18007, DG-18008 in Weiyuan County, Gansu and DG-18009 produced in Minle County, Gansu Province rank among the top 3 in all samples. Conclusions: These results demonstrated that the combination of HPLC chromatographic fingerprint and chemometrics offers an efficient and reliable approach for quality evaluation of ASR from different sources as Ancient Classical Prescriptions ingredients.

To investigate the effect of mortar composition on visco-elastic response of asphalt mixture, The Asphalt Mixture Performance Test (SPT) was conducted on several asphalt mixtures for different ratios of filler to asphalt (F/A) , fiber dosage and proportion of cement instead of mineral powder. The effect of F/A, fiber dosage and and proportion of cement replacement on visco-elastic mechanical parameters (dynamic modulus and phase angle) of asphalt mixtures are analyzed. The results indicate that the dynamic modulus of asphalt mixtures increases first and then decreases with the increases in F/A and fiber dosage. And the more significant differences in these dynamic moduli appear at the higher the load frequency. The asphalt mixture with the lowest F/A has the biggest phase angle, and the difference in the phase angles of those asphalt mixtures is not significant. The changes of phase angle have a close relationship with the load frequency. The resistance to permanent deformation of asphalt mixture can be greatly enhanced by adding fiber. The effect of cement instead of mineral powder on the viscoelastic property of asphalt mixture is relatively small, while the resistance to high-temperature deformation of asphalt mixture can be improved to some extent.

Abstract Background Yeast Saccharomyces cerevisiae is a widely-used system for protein expression. We previously showed that heat-killed whole recombinant yeast vaccine expressing mammalian myostatin can modulate myostatin function in mice, resulting in increase of body weight and muscle composition in these animals. Foreign DNA introduced into yeast cells can be lost soon unless cells are continuously cultured in selection media, which usually contain antibiotics. For cost and safety concerns, it is essential to optimize conditions to produce quality food and pharmaceutical products. Results We developed a simple but effective method to engineer a yeast strain stably expressing mammalian myostatin. This method utilized high-copy-number integration of myostatin gene into the ribosomal DNA of Saccharomyces cerevisiae. In the final step, antibiotic selection marker was removed using the Cre-LoxP system to minimize any possible side-effects for animals. The resulting yeast strain can be maintained in rich culture media and stably express mammalian myostatin for two years. Oral administration of the recombinant yeast was able to induce immune response to myostatin and modulated the body weight of mice. Conclusions Establishment of such yeast strain is a step further toward transformation of yeast cells into edible vaccine to improve meat production in farm animals and treat human muscle-wasting diseases in the future.