A compound that is used to treat athlete's foot may also be useful in controlling toxic algae that cause 'red tides' in oceans, Japanese researchers have indicated.
According to a report in Nature News, blooms of toxic algae that stain huge swathes of the oceans red, can cause havoc on the high seas.
They cause mass deaths in economically important fisheries, harm other marine species and can even close beaches to tourists.
So, researchers led by Takuji Nakashima, at the National Institute of Technology and Evaluation in Chiba, Japan, decided to investigate the effect of antifungal agents on two red-tide species, Chattonella marina and Heterocapsa circularisquama.
Some red tide phytoplankton have similar life cycles to that of the fungi that cause athlete's foot, explained Nakashima.
"As antifungal imidazole compounds have been used as herbicides, we considered that antifungals might have anti-algal activity," he added.
The researchers tested two such compounds: bifonazole and terbinafine, both of which are used in the treatment of athlete's foot. They applied varying concentrations of these compounds to cultures of both plankton species, and then counted the viable algal cells 24 hours later.
They found that both compounds have "potent algicidal activity". What's more, the effect could be reversed in C. marina at least, by adding ergosterol, an important component of the plankton's cell membranes.
Nakashima therefore suggests that the compounds work by inhibiting the synthesis of 'sterol' compounds such as ergosterol.
According to Donald Anderson, director of the Coastal Ocean Institute at Woods Hole Oceanographic Institution, Massachusetts, "In understanding red tide, this work helps to get at some of the mechanisms, membranes and cellular structures in these cells."