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Recently, composting cultivation method is widely used in oyster mushroom production. In this study, we focused on the effects of composting processes on nutritional qualities and antioxidant activity of Pleurotus floridanus mushroom fruiting bodies. Three treatments of different composting time (2, 4, and 5 days) were performed with an atmospheric sterilization treatment as the control. The results showed that the pH value, total carbon content, and total nitrogen content of substrate were critical parameters which would significantly affect mushroom qualities and bioactivities. Fruiting bodies of the control demonstrated significantly higher crude protein content, total amino acid content, and essential amino acid content than that of composting treatments. Moreover, fruiting bodies of treatment D4 and D5 manifested significantly higher crude polysaccharide contents. Crude polysaccharide of treatment D4 represented the highest scavenging ability toward both radical 3‐ethylbenzthiazoline‐6‐sulfonic acid (ABTS·+) and Hydroxyl radical (OH·). It suggests that composting processes is suitable for oyster mushroom cultivation based on nutritional and antioxidant qualities of fruiting bodies. [ABSTRACT FROM AUTHOR]

The numerical investigation focused on the shear behavior of prestressed concrete (PC) beams with small rectangular openings, using the software ABAQUS. Three variables, including the prestressing force, the height of the opening and its length, were considered. The numerical results exhibited a good agreement with the previous experimental outcomes, and the parametric analysis was conducted to study the local internal force distribution of two chords during the loading process. The results indicate that for RC beams with openings, the shear proportion variation of the top chord is stable as the opening size changes, while it decreases almost linearly with the increase of prestressing force for PC beams with openings. The position of contraflexure point is found to be proportional to the root of the reinforcement ratio of the chord, and it moves towards the support with the increase of the prestressing force. Furthermore, the empirical equations to determine the shear proportions and the position of contraflexure point between chords are established. [ABSTRACT FROM AUTHOR]

A novel 68 kDa laccase was purified from the mycorrhizal fungus Agaricus placomyces by utilizing a procedure that comprised three successive steps of ion exchange chromatography and gel filtration as the final step. The monomeric enzyme exhibited the N-terminal amino acid sequence of DVIGPQAQVTLANQD, which showed only a low extent of homology to sequences of other fungal laccases. The optimal temperature for A. placomyces laccase was 30° C, and optimal pH values for laccase activity towards the substrates 2,7'-azinobis[3-ethylbenzothiazolone-6-sulfonic acid] diammonium salt (ABTS) and hydroquinone were 5.2 and 6.8, respectively. The laccase displayed, at 30°C and pH 5.2, [K.sub.m] values of 0.392 mM towards hydroquinone and 0.775 mM towards ABTS. It potently suppressed proliferation of MCF 7 human breast cancer cells and Hep G2 hepatoma cells and inhibited human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) activity with an [IC.sub.50] of 1.8 µ/M, 1.7 µ/M, and 1.25 µ/M, respectively, signifying that it is an antipathogenic protein., 1. Introduction Laccase (E.C. 1.10.3.2), a polyphenol oxidase containing copper atoms in its catalytic center that plays a key role in lignin degradation in nature, was first demonstrated in plants [...]