Ursolic acid from Prunella vulgaris L. efficiently inhibits IHNV infection in vitro and in vivo.

Infectious hematopoietic necrosis virus (IHNV) is a fish viral pathogen that causes severe disease and huge economic losses in the salmonid aquaculture industry. However, anti-IHNV drugs currently are scarce. For the purpose of seeking out anti-IHNV drugs, the anti-IHNV activities of 32 medicinal plants were investigated by using epithelioma papulosum cyprini (EPC) cells. Among these plants, Prunella vulgaris L. (PVL) showed the strongest inhibition on IHNV replication with an inhibitory percentage of 99.3% at the concentration 100 mg/L. Further studies demonstrated that ursolic acid (UA), a major constituent of PVL, also showed a highly effective anti-IHNV activity. The half-maximal inhibitory concentration (IC50) at 72 h of UA on IHNV was 8.0 µM. Besides, UA could significantly decrease cytopathic effect (CPE) and the viral titer induced by IHNV in EPC cells. More importantly, UA also showed a strong anti-IHNV activity in vivo, as indicated by increasing the survival rate of rainbow trout and inhibiting viral gene expression. Intraperitoneal injection of UA increased the relative percentage of survival of rainbow trout by 18.9% and inhibited IHNV glycoprotein mRNA expression by > 90.0% in the spleen at the 1st-day post-infection. Altogether, UA was expected to be a therapeutic agent against IHNV infection in aquaculture.

Synthesis and antiviral activity of a new arctigenin derivative against IHNV in vitro and in vivo.

Viral diseases in aquaculture were challenging because there are few preventative measures and/or treatments. Our previous study indicated that imidazole arctigenin derivatives possessed antiviral activities against infectious hematopoietic necrosis virus (IHNV). Based on the structure-activity relationship in that study, a new imidazole arctigenin derivative, 4-(8-(2-ethylimidazole)octyloxy)-arctigenin (EOA), was designed, synthesized and its anti-IHNV activity was evaluated. By comparing inhibitory concentration at half-maximal activity (IC50), we found that EOA (IC50 = 0.56 mg/L) possessed a higher antiviral activity than those imidazole arctigenin derivatives in our previous study. Besides, EOA could significantly decrease cytopathic effect (CPE) and viral titer induced by IHNV in epithelioma papulosum cyprinid (EPC) cells. In addition, EOA significantly inhibited apoptosis induced by IHNV in EPC cells. Further data verified that EOA inhibited IHNV replication in rainbow trout, with reducing 32.0% mortality of IHNV-infected fish. The results suggested that EOA was more stable with a prolonged inhibitory half-life in the early stage of virus infection (1-4 days). Consistent with above results, EOA repressed IHNV glycoprotein gene expression in virus sensitive tissues (kidney and spleen) in the early stage of virus infection. Moreover, histopathological evaluation showed that tissues from the spleen and kidney of fish infected with IHNV exhibited pathological changes. But there were no lesions in any of the tissues from the control group and EOA-treaten group. In accordance with the histopathological assay, EOA could elicited anti-inflammation response in non-viral infected rainbow trout by down-regulating the expression of cytokine genes (IL-8, IL-12p40, and TNF-α). Altogether, EOA was expected to be a therapeutic agent against IHNV infection in the field of aquaculture.

Synthesis and in vitro activities evaluation of arctigenin derivatives against spring viraemia of carp virus.

Spring viraemia of carp virus (SVCV) is a viral fish pathogen causing high mortality in several carp species and other cultivated fish. However, robust anti-SVCV drugs currently are extremely scarce. For the purpose of seeking out anti-SVCV drugs, here a total of 35 arctigenin derivatives were designed, synthesized and evaluated for their anti-viral activities. By comparing the inhibitory concentration at half-maximal activity (IC50) of the 15 screened candidate drugs (max inhibitory response surpassing 90%) in epithelioma papulosum cyprini (EPC) cells infected with SVCV, 2Q and 6 A were chosen for additional validation studies, with an IC50 of 0.077 µg/mL and 0.095 µg/mL, respectively. Further experiments revealed that 2Q and 6 A could significantly decrease SVCV-induced apoptosis and have a protective effect on cell morphology at 48 and 72 h post-infection. Moreover, the reactive oxygen species (ROS) induced upon SVCV infection could be obviously inhibited by 2Q and 6 A, while SVCV-infected cells were clearly observed. On account of these findings, 2Q and 6 A could have a promising application for the treatment of infection of SVCV and provide a considerable reference for novel antivirals in aquaculture.

[Factors influence volatile oil content in Ocimun basilicum introduced from Xinjiang province to south-east China].

OBJECTIVE: To obtain the information on ecological adaptation of Ocimun basilicum introduced from Xinjiang to Hangzhou and study the effect of different harvesting times, drying methods, and different organs of Ocimun basilicum on Volatile oil content METHODS: Extraction was undertaken according to The Pharmacopoeia of China, 2010 edition. RESULTS: Sun-drying was the most efficient way to obtain Volatile oil compared with other methods. The largest biomass was harvested at 3rd, September. Furthermore, Volatile oil was found to accumulate mostly in the flowers and little in the stems. CONCLUSION: Ocimun basilicum can readily inhabit in Hangzhou and its economic value can be significant improved by growing two seasons per year. Only harvest leaves and flowers can significantly reduce the cost for transport and also increase oil extract rate of Volatile oil.

[Study on correlation between Atractylodes macrocephala viability and germination rate].

OBJECTIVE: To screen the optimized methods for detection seed viability and germination rate determination of Atractylodes macrocephala, and determine the relationship between seed viability and germination rate. METHOD: There were four methods, which including 2,3,5-triphynel tetrazolilum chloride (TTC) staining, red ink staining, BTB staining and Nongjia method, to evaluate the 12 A. macrocephala local varieties'seed viability and measure their germination rate. RESULT: Seed viability of A. macrocephala using TTC staining ranked the first compared to that of other three methods. Seed viability was significantly related with germination rate using TTC method. Their correlation coefficient reached 0.915 and regression equation was also found out between seed viability (X) and germination rate (Y), which was Y = -0.083 4 + 0.995 4X. CONCLUSION: TTC staining was the optimal method to determine A. macrocephala seed vitality. Furthermore, seed viability was significant related with germination rate of A. macrocephala.