Sanjay Sahay

Government Science and Commerce College, Benazir, Bhopal - 462 002, India.

DOI : https://dx.doi.org/10.13005/bpj/433

Abstract

Twenty nine isolates of black yeasts isolated from different environmental sources such as soil, water and different plant parts (diseased wood, leaf, flower and fruit). Their preferable niche has been found to be leaves followed by other plant parts. They were less frequent in other ecosystem studied. This is the first report about the ecological survey of black yeast in Bhopal.

Keywords

Ekant park; Black Yeast; Environmental

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Copy the following to cite this article: Sahay S. Environment-isolates of Black Yeasts from Ekant park. Biomed Pharmacol J 2013;6(2)

Copy the following to cite this URL: Sahay S. Environment-isolates of Black Yeasts from Ekant park. Biomed Pharmacol J 2013;6(2). Available from: http://biomedpharmajournal.org/?p=2779

Introduction

Increasing importance of black yeasts in the field of medical sciences, cosmetology and other fields of biotechnology have attracted the mycologists all over the world (de Hoog et al., 2005). In view of the photoprotective function of melanin, its preparations are widely used in dermatology and cosmetology. Melanins also possess antioxidant and antiradical activities (Paramonov et al., 2002; Brenner et al., 2008). Experiments using the crude enzyme were successful in whitening of the skin (U.S. Patent 7291340). Yeasts having affinities with both ascomycetes and basidiomycetes have been found to produce melanin. Some of them have also been associated with human mycoses.  Among melanized pathogenic fungi members of Herpotrichiellaceae (black yeasts and relatives) and its teleomorphic family chaetothyrialean fungi are associated with recurrent, clearly defined disease entities such as chromoblastomycosis and neurotropic dissemination in immunocompetent individuals ( Zeng et al. 2007).

In order to develop a comprehensive management strategy  in respect of  these melanized yeasts, knowledge of their natural ecology and evolution is essential. Several selective techniques have been developed enabling recovery of these fungi (de Hoog et al. 2005; Dixon et al. 1980, Prenafeta-Boldú et al. 2006, Satow et al. 2008, Zhao et al. 2008, Sudhadham et al. 2008) from various environments such as rock, creosote-treated wood, hydrocarbonpolluted soil, and hyperparasitism of fungi and lichens (Sterflinger et al. 1999, Wang & Zabel 1997, Lutzoni et al. 2001). It is therefore essential to monitor the presence of black in various environment not only to manage their pathogenic potential but also to derive benefit for human beings.

Materials and Methods

Study areas and materials

The soil from forests, parks, grasslands, pond and river water, flowers and leaves of locally available trees and wood samples from different localities of Bhopal city (India) were collected in polythene bags using disinfected spoons and forceps and stored at room temperature in the laboratory until processed. About 5 g of each sample was suspended in 50 ml of sterile physiological saline, containing chloramphenicol (0.05 mg ml–1). The suspension was shaken for 5 min on a vortex mixer and allowed to settle up to 60 min.

Fungal isolation

0.5 ml of above suspension was spread on PDA plates supplemented with chloramphenicol and incubated for a weeks at 30ºC.  The representative dark colonies  of different morphotypes were then isolated and purified by single cell isolation method and maintain on PDA slant at 4ºC or store as 10% glycerol stock at –15ºC.

Results

As indicated in Table 1, black yeasts were isolated from various samples tested.  There were altogether 29 black yeasts isolated from various sources; seventeen from leaves, five from flowers, three from date fruit, two from diseased Eucalyptus plant and one each from river bank soil and pond water. These black yeasts were purified by single cell isolation. These were then kept as glycerol stock at -12^oC.

Table 1: Black yeast isolates isolated from various environmental sources and sub-sources.

S.N.	Sources	Sub-sources	Isolates
1	Putranjiva roxburghii	Leaf	PRL21
2	Do	Do	PRL22
3	Do	Do	PRL23
4	Do	Do	PRL31
5	Jatropha	Do	JL41
6	Gardenia gumifera.	Do	GGL71
7	Do	Do	GGL72
8	Do	Do	GGL73
9	Do	Do	GGL743
10	Grevia robusta	Do	GRL22
11	Do	Do	GRL24
12	Salix spp.	Do	SSL53
13	Do	Do	SSL54
14	Butea monosperma	Do	BML61
15	Do	Do	BML62
16	Cauroptia guianensis	Do	CGL3
17	Do	Do	CGL4
18	Bauhinia varigata	Flower	BVF34
19	Do	Do	BVF38
20	Do	Do	BVF39
21	Accacia spp.	Do	FAY5
22	Do	Do	FAY6
23	Phoenix sylvestris	Fruit	PSFR3
24	Do	Do	PSFR4
25	Do	Do	PSFR41
26	Euclyptus spp	Diseased wood	EDW51
27	Do	Do	EDW52
28	Narmada river	Soil	NS22
29	Pond (Upper lake)	Water	PW3

 

Discussion

This is clear that the frequency of occurrence of black yeasts on leaf of the plant is more. The other plant parts stand nest as their favourite niche. Probably the availability of monosaccharides on young leaves and other plant parts attract these fungi.

Black yeasts have been isolated from various ecosystem earlier (Dixon et al., 1980; de Hoog et al. 2005; Satow et al., 2008). The most important aspect is of its association with disease lesion (deHoog et al., 2005; Sudhdham et al., 2008). Hence a concerted study on their occurrence role in various ecosystem is required.

References

1. deHoog, G.S., Matos, T., Sudhadham, M., Luijsterburg, K.F., Haase, G. Intestinal prevalence of the neurotropic black yeast Exophiala (Wangiella) dermatitidis in healthy and impaired individuals. Mycoses, 48: 142–145 (2005).
2. Paramonov, B., Turkovski, I., Potokin, I., Chebotarev, V. Photoprotective Activity of Melanin Preparations from Black Yeast-Like Fungus during Uvirradiation of Human Skin: Dependence on the oncentration . Bul. Exp. Biol. Med.,133: 4 (2002).
3. Mammone, T., Muizzuddin, N., Scnittager, S.F. Extracts from black yaest from whitening skin (Patent no. 7291340) (2002).
4. Zeng ,J.S., Sutton, D.A., Fothergill, W.A., Rinaldi, M.R., Harrak, M.J., de Hoog, G.S.  Spectrum of clinically relevant Exophiala species in the U.S.A. J. Clin. Microbiol., 45: 3713–3720 (2007).
5. Dixon, D.M., Shadomy, H.J., Shadomy, S. Dematiaceous fungal pathogens isolated from nature. Mycopathologia 70: 153–161 (1980).
6. Prenafeta-Boldú ,F.X., Summerbell, R.C., deHoog, G.S.  Fungi growing on aromatic hydrocarbons: biotechnology’s unexpected encounter with biohazard. FEMS Microbiol. Rev., 30: 109–130 (2006)..
7. Satow, M.M., Attili-Angelis, D., deHoog, G.S., Angelis, D.F., Vicente, V.A. Selective factors involved in oil flotation isolation of black yeasts from the environment Studies in Mycology 61: 157–163 (2008).
8. Sudhadham , M., Dorrestein, G., Prakitsin, S., Sivichai, S., Chaiwat, R., de Hoog, G.S. Two genotypes of the human-brain-infecting black yeast Exophiala dermatitidis indicate a possible origin of in the tropical rain forest. Studies in Mycology , 61: 145–156 (2008)..
9. Sterflinger, K., deHoog, G.S., Haase, G. Phylogeny and ecology of meristematic Ascomycetes. Studies in Mycology 43: 5–22 (1999).
10. Wang, C.J.K., Zabel, R.A. Identification manual for fungi from utility poles in the Eastern United States. Allen Press, Lawrence, U.S.A (1990).
11. Lutzoni ,F., Pagel, M., Reeb, V. Major fungal lineages are derived from lichen symbiotic ancestors. Nature, 411: 937–940 (2001).
12. Brenner, M. Hearing V.J. The Protective Role of Melanin Against UV Damage in Human Skin. Photochem Photobiol,  84: 539-549 (2008).