Phaeophyta Extracts Exhibit Antiviral Activity against Feline Calicivirus

Abstract

The objective of this study was to evaluate the antiviral activity of Phaeophyta extracts against feline calicivirus (FCV), used as a norovirus surrogate. A bioassay-guided cytotoxicity and virus infectivity assay revealed that methanolic extracts of Phaeophyta possessed significant antiviral activity against FCV. Among them, Eisenia bicyclis extract exhibited the highest antiviral activity against FCV. The 50% effective concentration of the extract (EC 50 ) inhibiting FCV viral replication by 50% was 80 µg/ mL. The extract also showed the highest selectivity index, calculated from the ratio of the median cellular cytotoxicity concentration (CC 50 ) and EC 50 , indicating antiviral efficacy against FCV. In addition, significant interruption of FCV infection was observed by pretreatment of host Crandall-Reese feline kidney cells with the E. bicyclis extract (200 µg/mL) prior to virus infection, in a dosedependent manner.

In vitro antiviral activity of dieckol and phlorofucofuroeckol-A isolated from edible brown alga Eisenia bicyclis against murine norovirus

“…Although various biological activities of marine organism have been reported, there are still many unknown potentials that could be utilized. We previously reported that E. bicyclis methanolic extract exhibit antiviral activity against FCV (Choi et al 2014). However, as described above, FCV may not be the most suitable surrogate for evaluating the efficacy of disinfectants against human norovirus (Cannon et al 2006, Zhang et al 2012.…”

“…Norovirus infection can usually be caused by contaminated water or food, and it spreads via human contact with infected materials through the fecal-oral route (Choi et al 2014). This infection has been recognized as a leading cause of epidemics with the symptoms of vomiting, diarrhea, mild fever, abdominal cramping, and nausea in the community (La Rosa et al 2013).…”

“…Norovirus could be effectively reduced by using disinfectants such as alcohols and povidone idodines (Belliot et al 2008). However, chemical sanitizers can cause various side effects in humans, such as fever and itching (Choi et al 2014). Recently, attempts have been made to find sustainable solutions from medicinal plants and marine organisms (Balunas and Kinghorn 2005, Jain et al 2008, Choi et al 2014.…”

“…However, chemical sanitizers can cause various side effects in humans, such as fever and itching (Choi et al 2014). Recently, attempts have been made to find sustainable solutions from medicinal plants and marine organisms (Balunas and Kinghorn 2005, Jain et al 2008, Choi et al 2014. Among marine organisms, chitosan and chitosan oligosaccharides were reported to be able to effectively reduce the infectivity of human enteric viral surrogates (feline calicivirus [FCV] F-9) (Su et al 2009, Davis et al 2012.…”

“…The brown algae have also been reported to exhibit several antimicrobial activities against pathogenic bacteria and FCV (Eom et al 2013a, Choi et al 2014, Lee et al 2014a. Since inadequate scientific research findings are available on the antiviral activity from marine organisms against MNV, the present study with MNV as a norovirus surrogate may have great contribution to the development of effective antiviral agents to control human norovirus.…”