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Antimicrobial resistance is a major threat to human health globally. Antrodia camphorata was grown in a malt/yeast extract broth liquid medium for 15 days. Then, 4-L fermentation broth was harvested, yielding 7.13 g of the ethyl acetate extract. By tracing the antimicrobial activity, 12.22 mg of the antimicrobial compound was isolated. The structure of 5-methyl-benzo [1,3]-dioxole-4,7-diol (MBBD) was elucidated using NMR and MS data analyses. The antibacterial activity of MBBD was detected through the microbroth dilution method. MBBD exhibited broad-spectrum antibacterial activity. The minimum inhibitory concentration (MIC) range of MBBD for drug-resistant pathogenic bacteria was 64–256 μg/mL, with the lowest MIC observed for Acinetobacter baumannii (64 μg/mL), followed by Pseudomonas aeruginosa (MIC = 128 μg/mL). Klebsiella pneumoniae, Staphylococcus aureus, Enterococcus faecalis, and Escherichia coli were also sensitive, with an MIC of 256 μg/mL. The MIC range of MBBD against 10 foodborne pathogens was 12.5–100 μg/mL. Based on the results of this study, MBBD exhibits broad-spectrum antibacterial activity, particularly demonstrating excellent inhibitory effects against A. baumannii. MBBD will be good candidates for new antimicrobial drugs. [ABSTRACT FROM AUTHOR]

Japonica rice variety Kanto 194 as the donor of resistance gene Stv-bi and low-amylose content gene Wx-mq was used to improve the resistance and eating quality of Wuyujing 3 by the breeding strategy of backcross. In continuous backcross and selfcross generations, the related molecular markers with Stv-bi and Wx-mq genes were utilized for genotypic detection by associated with resistance identification of rice stripe disease and agronomic traits selection. Finally, 10 improved lines with homozygous genotype Stv-biStv-biWx-mqWx-mq were obtained from BC3F4 generation. The results of comparative analysis indicated that most characters of these lines were consistent with those of recipient parent Wuyujing 3, except for the improved resistance, appearance and eating quality. By evaluation of the comprehensive performance of them, two excellent lines K01 and K04 were selected for further experiments.

GW2 is an important gene that regulates grain width and weight. We used cDNA clone to obtain the sequences of GW2 from large- and small-grained rice varieties, TD70 and Kasalath, respectively. Then, we developed a dCAPS (derived cleaved amplified polymorphic sequence) marker on the basis of the sequence difference between functional and nonfunctional GW2 genes to analyze the genotypes and phenotypes of recombinant inbred lines. Results showed that the sequence of GW2TD70 had a single nucleotide deletion at site 316 that generates a termination codon. This codon terminated the GW2 protein in advance. By contrast, the sequence of GW2Kasalath encoded an intact protein. A novel dCAPS marker was designed in accordance with a base A deletion at site 316 of the sequence. After the PCR product was digested by ApoI, TD70 showed 21 and 30 bp fragments, and Kasalath showed a 51 bp fragment. Up to 82 lines contained GW2TD70, and 158 lines contained GW2Kasalath. The lines that contained TD70 alleles displayed substantial increases in width and 1000-grain weight. This result suggested that GW2 played a critical role in rice breeding.

The synthesis of N, N'-l,4-bis( 4-methylphenyl) sulfonyl-liomopiperzine was studied with N-methylpyirolidone as solvent, NaOH as acid binding agent and 1,3-dichloropropane as cyclization reagent. The effects of reaction time, the molar ratio of reactants, reaction temperature, and the amount of sodium hydroxide on the yield of N,N'-1,4-bis(4-methylphenyl) sulfonyl-homopiperzine were investigated. The result showed that the order of effects was as follows: alkali amount > temperature > molar ratio of reactants. The yield could reach 81.93% under the conditions of 5 mmol N,N-bis(toluenesulfonyl)-1,2-ethylenediamine, 7.969 mmol 1,3-dichloropropane and 0.548 g sodium hydroxide,123 °C react 40 min. The kinetic analysis of the synthesis of N,N-1,4-bis(4-methylphenyl) sulfonyl-homopiperzine was carried out at 115, 125, 135 °C according to the second-order reaction mechanism, and the activation energy of this reaction was 76. 233 kJ/mol. [ABSTRACT FROM AUTHOR]

Nanjing 5718 is a rice variety with good eating quality approved by Jiangsu province in 2019 and was confirmed as super rice by the Ministry of Agriculture and Rural affairs in 2021. Studying its yield composition characteristics, photosynthetic characteristics, and physiological basis can be helpful to investigate photosynthetic traits of super rice variety, improve its photo- synthetic performance through genetic improvement, and provide the theoretical basis for high-yield breeding and cultivation of japonica rice. In this study, the parents of Nanjing 5718 and Huaidao 5, a widely popularized rice variety with the same growth period type, as the control, dry weight of aboveground of plant, chlorophyll contents, photosynthetic rates, and photochemical characteristics of photosystem II (PSII), core antenna protein expression, photosynthetic enzyme activities, and chloroplast ultrastructure were investigated in Nanjing 5718 from full expansion of flag leaves at the beginning of booting to 35 days after flowering. The results showed the pigment contents of the leaves in Nanjing 5718 were higher, which were close to male parent Yanjing 608. The net photosynthetic rates, dry weight, and PSII electron transfer activities of flag leaves at the late growth stage were significantly higher in Nanjing 5718 than those in parents and Huaidao 5. The light energy conversion performance of PSII was superior. The core antenna protein CP43 and CP47 were more stable under strong light and high temperature, and their adjustment ability of Nanjing 5718 was better than that of parents and Huaidao 5. In addition, the activities of RuBP carboxylase in flag leaves were higher, the contents of photosynthetic products were higher, the chloroplast structure was more stable, the senescence characteristics appeared later, and the chloroplast decay rates were slower in Nanjing 5718, compared with parents and Huaidao 5. The results indicated that high photosynthetic performance of flag leaves was the basis for the formation of high yield characteristics of super rice Nanjing 5718 with large panicles. The great activity and function of photosystem proteins were main factors of improving leaf photosynthesis, and the stability of chloroplast structure could provide powerful support for high photosynthetic efficiency of leaves. [ABSTRACT FROM AUTHOR]