Researchers continue seeking antifungal treatments
Scientists at Kazan Federal University have created new compounds based on terpene alcohols and azole heterocycles. The results of the study demonstrated their effectiveness, including against Candida fungi that cause thrush.
According Junior Research Associate Alan Akhmedov, he has been studying the properties of terpenoids since his student years. The interlocutor explained that terpenoids are molecules of plant origin that have fungistatic and bacteriostatic (slowing down pathogen growth) activity. At the same time, they are not harmful to the environment.
"Terpenoids are a fairly broad group of natural compounds of diverse structure. In almost any cosmetics you can find terpenoids, which are obtained by processing plant raw materials primarily from conifers. Geraniums on the windowsill are a vivid image from childhood, from songs and movies. This flower smells of one of the substances that we applied in our work," explained the scientist.
According to Alan Akhmedov, about a year and a half ago a group of scientists from Kazan University decided to study a wide range of biological activity of terpenoids, primarily antifungal. Given that they have low solubility in water, the KFU scientists came up with the idea of combining them with azoles—organic nitrogen-containing molecules—to increase their bioavailability. Azoles are able to embed themselves inside the cell membranes of fungi and bacteria and destabilize their function, leading to their death. So far, azoles have done a good job, but pathogens are gradually developing resistance to their action (similar to resistance to antibiotics), and many researchers are looking for alternatives to such drugs. KFU chemists have found that semi-synthetic compounds based on terpenoids can play a similar role.
"Our main idea is to use natural compounds, which will help reduce the cost of drugs and reduce the environmental risks associated with the accumulation of non-degradable synthetic analogs in the biosphere," Akhmedov noted. "In our compounds, we decided to increase the antifungal properties of terpenoids by introducing azoles, which may have antifungal activity. By combining synthetic (azoles) and natural (terpenoids) fragments with antifungal activity, we solved the problem of multifunctionality. Terpenoids provide not only antifungal properties, but also penetrate the skin well, which finds application in the manufacture of cosmetics."
In addition, many antifungal drugs based on azoles are toxic. New compounds produced by KFU chemists will be less toxic. The results of a study on the properties of the new compounds based on terpene alcohols were published in the journal Organic & Biomolecular Chemistry.
The effectiveness of the compounds was studied by researchers on the cells of fungi and bacteria, in particular, various strains of Candida. It was found that the new compounds have high fungistatic (able to inhibit the growth of new cells) and moderate fungicidal (able to kill cells) activity. Bactericidal and bacteriostatic activity against pathogenic strains of E. coli, Staphylococcus aureus and Bifidobacteria (nonpathogenic bacteria) was also tested.
"The results of the study showed the activity of the new compounds against pathogenic bacteria. At the same time, bifidobacteria showed low sensitivity to the studied compounds. The new compounds are more active against pathogenic bacteria, and against non-pathogenic—to a lesser extent," concluded the scientist.
The obtained results open up prospects for further research.
"It is possible to chemically optimize the obtained compounds to increase activity or other useful properties, as well as to expand the range of cells on which studies will be conducted," Akhmedov noted.
The use of such semi-synthetic compounds in the future will allow creating biocompatible antifungal drugs based on natural raw materials and products of their processing, the Kazan University scientists hope. In the future it is possible to develop a full-fledged preparation which will be applied to the affected areas of the skin.
Towards potential antifungal agents: synthesis, supramolecular self-assembly and in vitro activity of azole mono-, sesqui- and diterpenoids
pubs.rsc.org/en/content/articl … g/2023/ob/d3ob00528c
Provided by Kazan Federal University