Журнал «Актуальная инфектология» Том 9, №4, 2021
Вернуться к номеру
Antimycotic activity of macromycetes
Авторы: T.A. Krupodorova (1), T.A. Kizitska (2), O.V. Pokas (3), V.Yu. Barshteyn (1)
(1) — Institute of Food Biotechnology and Genomics of the National Academy of Sciences of Ukraine, Kyiv, Ukraine
(2) — Astrapharm LTD, Vishneve, Ukraine
(3) — SI «L.V. Gromashevsky Institute of Epidemiology and Infectious Diseases of the NAMS of Ukraine»,
Kyiv, Ukraine
Рубрики: Инфекционные заболевания
Разделы: Медицинские форумы
Версия для печати
Nowadays, one of the major and global health threats is fungal infections. The most common fungal pathogen is Candida albicans, which causes candidiasis. It can be subdivided into major groups: cutaneous, mucosal and systemic. Non-albicans Candida species like Issatchenkia orientalis (formerly Candida krusei) causes invasive candidiasis and onychomycosis. Another, no less dangerous fungal disease is mucormycosis — an infection caused by a group of filamentous molds within the order Mucorales. Mucormycosis can be classified of six forms: rhino-orbital-cerebral, pulmonary, cutaneous, gastrointestinal, disseminated, and mucormycosis of uncommon sites. Fungal diseases cause high mortality, especially in patients with AIDS, cancer, as well as in transplant individuals due to the immunosuppression. Recently, there has been an increase in the number of coronavirus disease (COVID-19) — associated mucormycosis (CAM). Diabetes mellitus is an independent risk factor for both severe COVID-19 and mucormycosis.
Also of concern is the continued emergence of new facts of resistance to the existing commercial drugs. At the same time, poor effect of some drugs and high possibility of fungal diseases, as well as the toxicity of drugs of modern drug therapy, emphasize the search for new effective antimycotic agents with low bayside effect. Interspecific fungal antagonism can be a powerful emerging tool in the development of mycoproducts (or biotech-products) against pathogenic fungi. A number of studies clearly demonstrate the significant antimycotic potential of macromycetes and indicate the relevance and prospects of such investigations.
The purpose of our study was to investigate the interspecific interactions between Macromycetes species and Candida albicans strains, Issatchenkia orientalis, and Mucor sp. fungi.
Thirty macromycetes from the Mushroom Culture Collection (IBK) of the M.G. Kholodny Institute of Botany of the National Academy of Sciences of Ukraine have been used. Saccharomycetaceae fungi (Candida albicans strains and Issatchenkia orientalis) were kindly supplied from the Culture Collection of Microorganisms of the Institute of Epidemiology and Infectious Diseases of the National Academy of Medical Sciences of Ukraine. Mucoraceae fungus — Mucor sp. has been received from the Collection of Microorganisms and Plant Lines for Food and Agricultural Biotechnology of the Institute of Food Biotechnology and Genomics of the National Academy of Sciences of Ukraine. Macromycetes were screened for their ability to suppress the mycelial growth of micromycetes in vitro dual-culture plate assays on potato dextrose agar by method described by Badalyan et al. (2002, 2004).
The interactions between fungi are of considerable theoretical and practical interest. In particular, it is important to understand the causal relationships of the biological and biochemical bases of the immune and defense responses of competing species. Co-cultivation with Saccharomycetaceae fungi led to a change in the morphological characteristics of some macromycetes fungal colonies such as formation of a mycelial ridge, aerial mycelia, barrages, drops of exudate, changed of the colony colour, and polymorphism of C. albicans clinical isolates. The obtained results indicate a significant antifungal activity of the studied 30 macromycetes against C. albicans strains and I. orientalis. During fungi co-cultivation different interaction reactions took place: deadlock after mycelial contact (type A) or at a distance (type B), overgrowth without initial deadlock (type C), partial (subtype CA1) or complete (subtype CA2) replacement after initial deadlock with contact. However, domination of replacement (78.7 %) of pathogenic fungi by macromycetes has been established. Furthermore, complete replacement took place almost twice more frequent (30.7 %) than partial replacement (19.3 %). Strong antagonistic activity with high antagonistic index (AI) was established by species Ganoderma applanatum (AI = 22.5), Lentinula edodes (AI = 21.0), Flammulina velutipes, Irpiciporus litschaueri and Pleurotus ostreatus (AI = 20.5), Crinipellis schevczenkoi (AI = 21), and Lyophyllum shimeji (AI = 21).
When co-cultivating of 30 studied macromycetes and micromycetes Mucor sp. various reactions of antagonism have been revealed: type A (16.67 % of the total number of investigated species of mushrooms), type B (3.33 %), type C (13.33 %), subtype CA1 (36.67 %), subtype CA2 (30.00 %). According to the results it was established the predominance of unilateral antagonism (inhibits the development or causes the death of macromycetes) Mucor sp. at the level of 80 %, including type C and subtypes CA1 and CA2. Bilateral antagonism of fungi is evidenced by the revealed growth reactions of types A and B. Mutual inhibition of colony growth on contact (type A) was found for six species: Ganoderma applanatum, Fomitopsis pinicola, Laetiporus sulphureus, Crinipellis schevczenkoi, Lyophyllum shimeji and Ophiocordyceps sinensis. The type B was revealed for Lentinula edodes, the presence of a transparent zone of 5–8 mm was visually observed, which indicates diffusion into the agar of antifungal substances capable not only of inhibiting micromycete growth but also of inhibiting its growth at a distance. It should also be noted the formation of colorless mycelium Mucor sp. in the form of a small roller opposite the colony of L. edodes. Maximal inhibition index of Mucor sp. growth has been found with F. pinicola co-cultivation.
The study touched on antagonistic activity is one of the integral stages into understanding fungal-fungal competition. The results clearly indicate effectiveness of Macromycetes against Saccharomycetaceae pathogenic fungi via contact antagonism and little antagonistic activity against Mucor sp. Performed screening allows to determine the most active fungi with strong antimycotic activity: Crinipellis schevczenkoi, Flammulina velutipes, Fomitopsis pinicola, Ganoderma applanatum, Irpiciporus litschaueri, Lentinula edodes, Lyophyllum shimeji, Pleurotus ostreatus. These fungi are promising species for further studies to investigation and isolation potential antimycotic metabolites.