In vitro antifungal activity and possible mechanisms of action of chelerythrine.

Chelerythrine (CHE) possesses broad pharmacological activities. In this study, the extract of Chelidonium majus L. were characterized by high performance liquid chromatography (HPLC), infrared radiation (IR) spectroscopy and nuclear magnetic resonance (NMR). It was proved that the extract was CHE. The antifungal activity of CHE against five fungal pathogens of rice was researched in vitro, revealing that CHE inhibited Ustilaginoidea virens (U. virens) and Cochliobolus miyabeanus (C. miyabeanus) with 50% effective concentrations (EC50) of 6.53 × 10-3 mg/mL and 5.62 × 10-3 mg/mL, respectively. When the concentration of CHE was 7.5 × 10-3 mg/mL, the inhibition rate of U. virens reached 56.1%. Moreover, CHE (4 × 10-3 mg/mL) exhibited the greatest efficacy in inhibiting spore of U. virens growth with an inhibition rate as high as 86.7%. CHE displayed the best inhibitory activity against U. virens at the concentration of 7.5 × 10-3 mg/mL, compared with the other two isoquinoline alkaloids and commercial fungicide validamycin. After treating U. virens mycelia with CHE, twisted and atrophied mycelia were observed by optical microscopy. SEM results demonstrated narrow and locally fractured mycelium. TEM observations showed that the cell wall had become thin and broken, and most organelles were difficult to recognize. Furthermore, membrane of mycelia was destroyed and reactive oxygen species (ROS) of spores was accumulated, which induced apoptosis of pathogenic fungi. From these results, our understanding of the mechanisms of antifungal activity of CHE against U. virens was enriched and this research is relevant for developing novel pesticides.

Effects of altrenogest on reproductive performance of gilts and sows: A meta-analysis.

Altrenogest is a synthetic progestogen that allows for synchronization of the time of estrus in swine. Its effect on reproductive performance, however, is inconsistent due to conflicting data in the scientific literature. A meta-analysis of published data, therefore, was performed to determine whether altrenogest affects gilt and sow reproductive performance. Altrenogest administration to pigs enhanced the number of piglets born alive per litter (NBA), total number born per litter (TNB), estrous rate within 10 days after treatment (ER10) and pregnancy rate (PR) as well as the farrowing rate (FR) of gilts. The NBA and TNB of primiparous sows fed altrenogest were improved although FR was less. In multiparous sows, altrenogest treatment did not result in any improvement for any of the five analyzed variables. Additionally, 14-day treatment regimens for gilts and >8-days for primiparous sows improved reproductive performance and extent of estrous synchrony. The effects of altrenogest on reproductive performance of swine were parity and treatment duration dependent.