Genome-wide identification of G-protein coupled receptors (GPCRs) and their expression profile in response to ß-cypermethrin stress in Zeugodacus cucurbitae.

G-protein coupled receptors (GPCRs) are the largest and most diverse transmembrane receptor family in the cell. They are involved in regulating a wide range of biological processes, including behavior, reproduction, and development. However, GPCRs have not yet been identified in Zeugodacus cucurbitae. The current study focuses on the GPCRs identification, classification, distribution, and their expression analysis under ß-cypermethrin stress to uncover novel targets for pest management and assist in the development of effective strategies for controlling the melon fly population. We identified 80 GPCRs genes including 50 GPCRs identified in family A, 17 GPCRs identified in family B, 8 identified in family C, and 5 identified in family F. Z. cucurbitae GPCRs showed significant differences in both the number of genes in families or subfamilies, as well as the sequencing of the genes. Interestingly, newly identified GPCRs genes are expressed differently at various developmental stages of Z. cucurbitae. Further, we evaluated these 80 GPCRs using Realtime quantitative PCR to confirm their expression between ß-cypermethrin-resistant (RS) strain and susceptible strain (SS) of Z. cucurbitae. We identified 50 GPCR genes were highly overexpressed in a RS. Among these genes, eight genes were strongly induced by the 30% lethal concentration (LC) while two genes were significantly increased by the 50% LC of ß-cypermethrin. This first genome-wide profiling and characterization of GPCRs could lay foundation for unraveling detoxification mechanism and target site modifications which may improve the insect resistance and could be effective insecticide targets for Z. cucurbitae management.

Response surface optimization of ultrasound-assisted flavonoids extraction from the flower of Citrus aurantium L. var. amara Engl.

Citrus aurantium L. var. amara Engl is a member of genus Citrus (Rutaceae) and has been used in Chinese medicine with the effectiveness of digestant and expectorant. Ultrasonic-assisted extraction process for maximum flavonoids from the flower of Citrus aurantium L. var. amara Engl was investigated by response surface methodology. Through single factor experiment, ranges of the main variables (including ethanol concentration, solid/liquid ratio, extraction time and temperature) affecting the extraction yield of flavonoids were confirmed. Box-Behnken central composite design consisting of 24 experimental runs and 5 replicates at zero point was then applied and a regress model was obtained to predict the optimal extraction yield. The ANOVA indicated that the regression equation fits very well with the actual situation, reflecting the relationship between the extraction yield of flavonoids and extraction conditions. The optimal conditions were as follows: extraction temperature 72.11 degrees C, time 51.89 min, ethanol concentration 51.19% and liquid/solid ratio of 40:10. Under the optimal conditions, the maximum response value of yield (1.88%) was consistent with the experimental value (1.87%), indicating the feasibility and validation of response surface methodology in optimizing the extraction of flavonoids from the flower of Citrus aurantium L. var. amara Engl.

Comparison of the sedative and hypnotic effects of flavonoids, saponins, and polysaccharides extracted from Semen Ziziphus jujube.

Semen Ziziphus jujube (SZJ), the seeds of Ziziphus jujuba Mill. var. spinosa, is a kind of traditional Chinese medicine used for its action on insomnia. In order to analyze the effective component, we investigated and compared the sedative and hypnotic effects of three kinds of compounds, flavonoids, saponins, and polysaccharides. Flavonoids, saponins, and polysaccharides were extracted from SZJ and orally administered to mice separately at 17 g kg(-1) per day for certain days before animal tests. Spontaneous motility and coordinated movement tests were used to observe the effects of the three kinds of compounds on the mouse behavior, and sodium barbital-induced sleeping time of mouse were tested to analyze the effects of the three kinds of compounds on the sleep of mouse. Results show that flavonoids and saponins caused a significant reduction of walking time and coordinated movement ability of mouse, significantly prolonged its sleeping time at 40 mg kg(-1), ip, subthreshold dose and increased the sleeping number of animals at 50 mg kg(-1), ip, superthreshold dose induced by coeliac injection of sodium barbital. Polysaccharides did not show any significance in all animal tests. Comparative analysis showed that saponins had a more effective sedative and hypnotic function than that of flavonoids, polysaccharides did not show a sedative and hypnotic effect.