@article {515, title = {Evaluation of In vitro Antiviral Activity of Datura metel Linn. Against Rabies Virus}, journal = {Pharmacognosy Research}, volume = {8}, year = {2016}, month = {August 2016}, pages = {265-269}, type = {Original Article}, chapter = {265}, abstract = {

Objective: The soxhlet and cold extracts of Datura metel Linn. were evaluated for in vitro antirabies activity. Materials and Methods: Soxhlet and cold extraction method were used to extract Datura (fruit and seed) extracts. In vitro cytotoxicity assay was performed by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide assay. Based on the CC50 range, the in vitro antirabies activity of the extracts was screened by rapid fluorescent focus inhibition test and molecular method. Results: The Datura (fruit and seed) extracts were not cytotoxic below 5 mg/ml (CC50). Titer of 10-4 rabies virus challenge virus standard (RV CVS) (1 50\% tissue culture infective dose [1 TCID50]) was obtained by RFFT method and the challenge dose of 10 TCID50 was used for antirabies assay. Datura fruit and seed (soxhlet and cold) extracts showed 50\% inhibition of RV CVS at 2.5 mg/ml and 1.25 mg/ml (inhibitory concentration 50\% [IC50]), respectively. The tested extracts showed selectivity index (CC50/IC50) ranging from 2 to 4. The viral RNA was extracted and real-time reverse transcription-polymerase chain reaction was performed which also revealed a 2-fold reduction of viral load at 1.25 mg/ml of the Datura seed (soxhlet methanolic and cold aqueous) extracts. Conclusion: To the best of our knowledge, this is the first study of in vitro antiviral activity of D. metel Linn. against rabies virus. Datura seed extracts have a potential in vitro antirabies activity and, in future, can be further screened for in vivo activity against rabies virus in murine model.

}, keywords = {Antirabies, Antiviral assay, cytotoxicity, Datura, Rapid fluorescent focus inhibition test}, doi = {10.4103/0974-8490.188874}, author = {Soumen Roy and Sandeepan Mukherjee and Sandip Pawar and Abhay Chowdhary} } @article {858, title = {A Modified MS2 Bacteriophage Plaque Reduction Assay for the Rapid Screening of Antiviral Plant Extracts}, journal = {Pharmacognosy Research}, volume = {2}, year = {2010}, month = {September 2010}, pages = {221-228}, type = {Original Article}, chapter = {221}, abstract = {

Introduction: Traditional methods of screening plant extracts and purified components for antiviral activity require up to a week to perform, prompting the need to develop more rapid quantitative methods to measure the ability of plant based preparations to block viral replication. We describe an adaption of an MS2 plaque reduction assay for use in S. aureus. Results: MS2 bacteriophage was capable of infecting and replicating in B. cereus, S. aureus and F+ E. coli but not F- E. coli. Indeed, both B. cereus and S. aureus were more sensitive to MS2 induced lysis than F+ E. coli. When MS2 bacteriophage was mixed with Camellia sinensis extract (1 mg/ml), Scaevola spinescens extract (1 mg/ml) or Aloe barbadensis juice and the mixtures inoculated into S. aureus, the formation of plaques was reduced to 8.9 {\textpm} 3.8\%, 5.4 {\textpm} 2.4\% and 72.7 {\textpm} 20.9\% of the untreated MS2 control values respectively. Conclusions: The ability of the MS2 plaque reduction assay to detect antiviral activity in these known antiviral plant preparations indicates its suitability as an antiviral screening tool. An advantage of this assay compared with traditionally used cytopathic effect reduction assays and replicon based assays is the more rapid acquisition of results. Antiviral activity was detected within 24 h of the start of testing. The MS2 assay is also inexpensive and non-pathogenic to humans making it ideal for initial screening studies or as a simulant for pathogenic viruses.

}, keywords = {Aloe vera, Antiviral assay, Camellia Sinensis, MS2 bacteriophage, Plaque reduction assay, Scaevola spinescens}, doi = {10.4103/0974-8490.69108}, author = {Ian Cock and FR Kalt} }