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A filamentous fungus producing polygalacturonase (29.2 U/mL) was isolated from orchard soil in northern Guangxi, and identified as Trichoderma koningiopsis. Using polygalacturonic acid as the substrate, the optimum reaction temperature of the enzyme was 50 ℃, and it maintained more than 70% of the maximum activity at 50 ℃ for 1 h, which was identified as a medium-high temperature tolerant enzyme. The enzyme had unique weakly acidic catalytic characteristics. The optimum reaction pH was 5.0, and it retained 73% of its maximum activity at pH 6.0, and was tolerant to pH 2.5–8.0. Zn2+ partially activated the enzyme activity, while Mn2+ inhibited the enzyme. It could depectinize five weakly acid fruit pulps (papaya, banana, banana, and white- and red-fleshed pitaya) but to different extents. The yield of juice of banana pulp increased by 24.4%, the viscosity of papaya pulp decreased by 82.5%, and the transmittance of red-fleshed pitaya pulp increased by 31.9%, indicating good depectinization efficiency for the three fruits. The polygalacturonase-producing strain has good prospects for its application in juice production from tropical and subtropical perishable fruits.

Asymmetric electrosynthesis provides an efficient and controllable route for chiral synthesis. In comparison to traditional symmetric synthesis methods, asymmetric electrosynthesis typically operates under milder conditions, reducing waste generation and energy consumption. This aligns with the current trend in green chemistry, contributing to the development of environmentally friendly synthetic pathways. Apart from reactions initiated with chiral substrates, introducing appropriate chiral factors during the electrochemical process is crucial. In this context, chiral electrodes have garnered significant attention due to their advantages such as high catalytic activity, enantioselectivity, and reusability. This concept aims to introduce the preparation of three main types of chiral electrodes over the past decade, including chiral modified electrodes, chiral immobilized electrodes and chiral imprinted electrodes, and their applications in asymmetric electrosynthesis. The article provides insights into the current state of the field and outlines prospects for future research. [ABSTRACT FROM AUTHOR]

Based on OpenGL, this paper presented a local 3D scene reconstruction from the frame buffers (including color buffer and depth buffer) after 3D scene rendered. According to projection principles and depth buffer characteristics, it discussed an inverse prooection processing and obtained theoretically a 3D vertex reconstruction method. As a result, it transformed a l valid pixels within frame buffers and generated a 3D vertex set which was a point cloudy model in the camera space in the conducted experiments. Obviously, this cloudy model was a kind of a sample of the original 3D scene in current camera system and named as virtual vision model(VVM). Secondly, it analyzed the point-wise precision of VVM detailed. The results of experiments show that VVM appears very high relative accuracy to the original 3D scene. Above all, the reconstruction method appears natural multi-resolution feature with respect to the resolution of frame buffers and supports scene simplification and streaming transmission. On the other hand, this method is capable of abstracting VVM real-time from the common 3D software easily without any details of 3D scene known previously, which provides a new approach acquiring 3D data efficiently. [ABSTRACT FROM AUTHOR]

Objective: The pathogenesis of diarrhea-predominant irritable bowel syndrome (IBS-D) is related to damage to the intestinal mucosal barrier function. Based on the Mast cell (MC)/Tryptase/Protease-activated receptor-2 (PAR-2)/Myosin light chain kinase (MLCK) pathway, this study explored the effect of electroacupuncture (EA) on IBS-D rats and its possible mechanism of protecting the intestinal mucosal barrier., Methods: The IBS-D rat model was established by mother-offspring separation, acetic acid enema, and chronic restraint stress. The efficacy of EA on IBS-D rats was evaluated by observing the rate of loose stool (LSP) and the minimum volume threshold of abdominal withdrawal reflex (AWR) in rats. Mast cells and the ultrastructure of intestinal mucosa were observed by H&E staining, toluidine blue staining, and transmission electron microscopy. The expression levels of Tryptase, PAR-2, MLCK, zonula occludens-1 (ZO-1), and Occludin in rats were detected by ELISA, qRT-PCR, and western blot., Results: After 7 days of intervention, compared to the IBS-D group, the loose stool rates of rats in IBS-D + EA group and IBS-D + ketotifen group were decreased ( P < 0.01), the minimum volume thresholds of AWR were improved ( P < 0.01), the inflammation of colon tissue decreased, the number of MCs were decreased ( P < 0.01), the expression of Tryptase, PAR-2, and MLCK were lowered ( P < 0.01, P < 0.05), and the expression of ZO-1 and Occludin were enhanced ( P < 0.01, P < 0.05). Compared to the EA group, there was no significant difference in each index between the ketotifen groups ( P > 0.05)., Conclusion: EA has a good therapeutic effect on IBS-D rats. Regulating the MCs/Tryptase/PAR-2/MLCK pathway may be a mechanism to protect the intestinal mucosal barrier., Competing Interests: None., (AJTR Copyright © 2024.)