Identification of light-independent inhibition of human immunodeficiency virus-1 infection through bioguided fractionation of <it>Hypericum perforatum</it>

• Main Authors: Widrlechner Mark P, Murphy Patricia, Hauck Cathy, Carpenter Susan, Wills Nickolas, Wiemer David F, Neighbors Jeffrey D, Oh ChoonSeok, Brindley Melinda A, Price Jason P, Maury Wendy, Delate Kathleen, Kumar Ganesh, Kraus George A, Rizshsky Ludmila, Nikolau Basil
• Format: Article
• Language: English
• Published: BMC 2009-07-01
• Series: Virology Journal
• Online Access: http://www.virologyj.com/content/6/1/101

<p>Abstract</p> <p>Background</p> <p>Light-dependent activities against enveloped viruses in St. John's Wort (<it>Hypericum perforatum</it>) extracts have been extensively studied. In contrast, light-independent antiviral activity from this species has not been investigated.</p> <p>Results</p> <p>Here, we identify the light-independent inhibition of human immunodeficiency virus-1 (HIV-1) by highly purified fractions of chloroform extracts of <it>H. perforatum</it>. Both cytotoxicity and antiviral activity were evident in initial chloroform extracts, but bioassay-guided fractionation produced fractions that inhibited HIV-1 with little to no cytotoxicity. Separation of these two biological activities has not been reported for constituents responsible for the light-dependent antiviral activities. Antiviral activity was associated with more polar subfractions. GC/MS analysis of the two most active subfractions identified 3-hydroxy lauric acid as predominant in one fraction and 3-hydroxy myristic acid as predominant in the other. Synthetic 3-hydroxy lauric acid inhibited HIV infectivity without cytotoxicity, suggesting that this modified fatty acid is likely responsible for observed antiviral activity present in that fraction. As production of 3-hydroxy fatty acids by plants remains controversial, <it>H. perforatum </it>seedlings were grown sterilely and evaluated for presence of 3-hydroxy fatty acids by GC/MS. Small quantities of some 3-hydroxy fatty acids were detected in sterile plants, whereas different 3-hydroxy fatty acids were detected in our chloroform extracts or field-grown material.</p> <p>Conclusion</p> <p>Through bioguided fractionation, we have identified that 3-hydroxy lauric acid found in field grown <it>Hypericum perforatum </it>has anti-HIV activity. This novel anti-HIV activity can be potentially developed into inexpensive therapies, expanding the current arsenal of anti-retroviral agents.</p>