Development of Fusion-Based Assay as a Drug Screening Platform for Nipah Virus Utilizing Baculovirus Expression Vector System.

Nipah virus (NiV) is known to be a highly pathogenic zoonotic virus, which is included in the World Health Organization Research & Development Blueprint list of priority diseases with up to 70% mortality rate. Due to its high pathogenicity and outbreak potency, a therapeutic countermeasure against NiV is urgently needed. As NiV needs to be handled within a Biological Safety Level (BSL) 4 facility, we had developed a safe drug screening platform utilizing a baculovirus expression vector system (BEVS) based on a NiV-induced syncytium formation that could be handled within a BSL-1 facility. To reconstruct the NiV-induced syncytium formation in BEVS, two baculoviruses were generated to express recombinant proteins that are responsible for inducing the syncytium formation, including one baculovirus exhibiting co-expressed NiV fusion protein (NiV-F) and NiV attachment glycoprotein (NiV-G) and another exhibiting human EphrinB2 protein. Interestingly, syncytium formation was observed in infected insect cells when the medium was modified to have a lower pH level and supplemented with cholesterol. Fusion inhibitory properties of several compounds, such as phytochemicals and a polysulfonated naphthylamine compound, were evaluated using this platform. Among these compounds, suramin showed the highest fusion inhibitory activity against NiV-induced syncytium in the baculovirus expression system. Moreover, our in silico results provide a molecular-level glimpse of suramin's interaction with NiV-G's central hole and EphrinB2's G-H loop, which could be the possible reason for its fusion inhibitory activity.

Acute toxicity test of kenikir leaf (Cosmos caudatus H.B.K) ethanolic extract on Wistar white male rats with fixed dose procedure method and its effect on histopathology of pancreatic cells.

In this study, acute toxicity of kenikir leaf (Cosmos caudatus HBK) ethanolic extract was conducted on Wistar white male rats with fixed dose procedure. The extraction method used was maceration using 70% ethanol. A dose of 2000 mg/kgBW was determined as the starting dose based on the preliminary test result. The rats used in the main test were divided into the normal group and the 2000 mg/kgBW dose group, each used five animals in each group. The results of the test showed that there were no deaths or toxic symptoms both of the normal group and the 2000 mg/kgBW dose group. The conducted preliminary test results a dose of 2000 mg/kgBW as the starting dose. Next, main test is done toward two groups of rats: Normal group and 2000 mg/kgBW dose group each consist of five animals. The main test results in neither deaths nor toxic symptoms from those groups. The range of toxic doses of kenikir leaf ethanolic extract that can cause acute toxicity is >2000 mg/kgBW, and hence, this experiment classified in the practically nontoxic category. Statistical analysis on effect to macroscopic organs of the liver, heart, and kidney showed no significance (P > 0.05) from kenikir leaf ethanolic extract. Average levels of biochemical parameters from the 2000 mg/kgBW group and the normal group were in the normal range. Ethanolic extract at a dose of 333 mg/kg BW does not cause severe pancreatic damage, and hence, it is considered safe for use as an antidiabetic.

Phytochemical and antioxidant activity evaluation of the bark of Tampoi ( Baccaurea macrocarpa).

Background: Tampoi ( Baccaurea macrocarpa) is a tropical rainforest plant that produces edible fruit and is native to Southeast Asia, especially East Kalimantan, Indonesia. Previous research showed that Tampoi potentially can be developed as a drug. It was reported that the extract of Tampoi fruit displayed antioxidant activity, which was correlated with its phenolic and flavonoid substances. There is no information about the antioxidant activity of other parts of this plant, such as the bark, which might also have this kind of activity. Therefore, the aim of this study was to evaluate the phytochemical, toxicity, and antioxidant activity of the bark of Tampoi. Methods : The bark of Tampoi was extracted with methanol and concentrated using rotary evaporator to obtain the methanol extract of the bark. Secondary metabolites of this extract was determined using phytochemical analysis. Afterward, the methanol extract was tested for its toxicity using brine shrimp lethality test and antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl method. Results: Phytochemical evaluation results showed that the methanol extract of bark of this plant contains several secondary metabolites including alkaloids, flavonoids, phenolics, steroids, and triterpenoids. The toxicity test displayed no toxic property due to a LC 50 value above 1000 ppm. For antioxidant activity, the result exhibited that the methanol extract of bark of this plant could be categorized as an active extract with IC 50 value of 11.15 ppm. Moreover, based on gas chromatography-mass spectrometer analysis, there are 37 isolated compounds from the bark, one of which is methylparaben, a phenolic predicted to act as an antioxidant. Conclusion : The results obtained in this research demonstrated that the bark of Tampoi ( B. macrocarpa) has potential as an antioxidant.