Fermentation of soybean is a process in which soy proteins are broken down into small peptides to exert various physiological functions beyond their nutritional value and to improve food source bioactive components responsible for health benefits. Enzymatic hydrolysis could speed up the degradation of proteins during fermentation of soybean, thus resulting in higher peptide production. In the present study, fermented soy meal (fermented with Bacillus subtilis from Douchi) was hydrolyzed by thermolysin, and the water extraction was then separated into four fractions using ultrafiltration membranes. Their vasorelaxation activities were screened, and the most potent fraction was further isolated and purified to obtain four peptides. Briefly, three peptides exerted a dose-dependent vasorelaxation (0.01-4.10 μM) in the phenylephrine preconstricted thoracic aorta ring of Sprague-Dawley rat (relaxation actions were all endothelium-independent), while one peptide induced vasoconstriction. Furthermore, an independent causal relationship between vasorelaxation and angiotensin converting enzyme (ACE) inhibition activities was found.

The fermentation medium of Micromonospora Y15 was optimized to enhance the production of antimicrobial metabolites with the antimicrobial activity tested against Listeria monocytogenes. First, the optimal medium components (carbon source, nitrogen source and inorganic salt) were determined by the single factor experiment. Second, the Plackett-Burman experiment was used to screen significant factors. Third, the steepest ascent experiment was undertaken to figure out the optimal region of the significant factors. Finally, the central composite experiment was conducted to optimize the final medium components. The single factor experiment results suggested that the optimal medium components were soluble starch, beef extract, peptone, NaCl, K 2 HPO 4 , MgSO 4 , and FeSO 4 , while the Plackett-Burman experiment demonstrated that beef extract, K 2 HPO 4 and soluble starch were significant factors affecting antimicrobial activity. The steepest ascent experiment results further showed the central point of three significant factors were 1.00 g/L of K 2 HPO 4 , 25.00 g/L of soluble starch and 18.00 g/L of beef extract, respectively. Response surface analysis revealed that the optimum values of the tested significant variables for the production of antimicrobial metabolites were 1.03 g/L of K 2 HPO 4 , 27.67 g/L of soluble starch and 18.30 g/L of beef extract, accordingly. Under this optimal condition, the antimicrobial activity of the fermented medium was 1236.79 § 14.56 AU/mL, which increased 3.86 times compared with the initial medium. We thus concluded that the medium composition optimized in the study would be helpful for the production of antimicrobial metabolites by Micromonospora Y15.

Optimized Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) pretreatment methods for determination of six polychlorinated biphenyls (PCBs) residues in fish and aquatic invertebrates samples were investigated. Large volume injection (LVI) coupled gas chromatography tandem mass spectrometry (GC-MS/MS) with selected reaction monitoring (SRM) was used to provide a very sensitive and selective means of analyzing PCBs via internal calibration. Three analytical processes were validated and compared, and the florisil Celite ® 545 pretreatment method was selected. Performance characteristics, such as linearity, limit of detection (LOD), limit of quantization (LOQ), recovery and precision (relative standard deviation, RSD) were studied. The method was applied to 233 samples obtained from local markets, which was useful and thus suggested that the method could serve as a screening model for PCB residues analysis.

The aim of the study is to determine the features of interpretation of Olenka’s image in Chinese literary criticism from 1907 to the present day. The article shows the dynamics of perception of Chekhov’s heroine image in various socio-historical conditions in China. The scientific novelty of the work lies in the fact that the article is the first systematic analysis of the reception of Olenka’s image in China and provides new material in this regard; the opposite points of view of the Chinese critics on the image of the woman depicted by A. P. Chekhov are indicated; parallels are drawn between the interpretations of the image of the heroine from the story “The Darling” by the Russian and Chinese literary critics and writers, in particular, common points in critical perceptions of Olenka between the Chinese researchers and contemporaries of A. P. Chekhov (L. N. Tolstoy, M. Gorky) are determined. As a result, it is proved that the image of the considered heroine of Chekhov’s work has been and is currently being severely criticized in China in connection with the peculiarities of the Chinese society development and the process of female emancipation, but there are also positive opinions about the heroine, emphasizing her virtue, ability to exalted feelings, devotion love.