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Degradation of keratin substrates by fungi isolated from sewage sludge

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Abstract

Four fungal species including two dermatophytes and two saprophytes were isolated from sewage sludge samples at Basrah (Iraq) they were tested for their degradative ability towards three types of keratin substrates (human hair, chicken feathers and wool). The rate of keratin degradation was expressed as weight loss over three weeks of incubation using a liquid culture medium. Human hair had the highest degradation rate by colonization of Chrysosporium pannicola and Microsporum gypseum at a rate of 62% and 4% respectively. Chicken feathers were highly degraded by Aspergillus flavus (32%) while wool degradation was highest by C. pannicola (45.5%) and Trichophyton mentagrophytes var. erinacei (38%). There was a significant difference (p < 0.00l) in keratin substrate degradation rates by the examined fungi. Keratinase activity was highest for C. pannicola and M. gypseum in the culture medium baited with human hair. Aspergillus flavus revealed the highest activity of this enzyme in cultures amended with chicken feathers while T. mentagrophytes var. erinacei showed highest keratinase activity in cultures with wool substrate. The amount of protein released into the culture medium varied among the tested fungi. The medium's alkalinity increased over incubation time from 6.5 to 7.8. Microscopic examination showed maceration of the keratin substrates by the fungi.

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References

  1. Kunert J. Biochemical mechanism of keratin degradation by the actinomycete Streptomyces fradiae and the fungus Microsprum gypseum: A comparison. J Basic Microbiol 1989; 9: 597–604.

    Google Scholar 

  2. Kunert J. Biochemical mechanism of keratin degradation by keratinolytic fungi. In: Govil CM, Bilgrami KS, Singh D, eds. Platinum jubilee volume of Indian Botanical Society. Meerut, India: Agrawal Printers, 1995; 89–98.

    Google Scholar 

  3. Kushwaha RKS. The in vitro degradation of peacock feathers by some fungi. Mycosen 1981; 26: 324–326.

    Article  Google Scholar 

  4. Marchisio VF, Fusconi A, Rigo S. Keratinolysis and its morphological expression in hair digestion by airborne fungi. Mycopathologia 1994; 127: 103–115.

    Article  Google Scholar 

  5. Muhsin TM, Hadi RB. Dermatophytes and other keratinolytic fungi from sewage sludge at Basrah, Iraq. Mycoses 2000 (in press).

  6. Bahuguna S, Kushwaha RKS. Hair perforation by keratinophylic fungi. Mycoses 1989; 32: 340–343.

    Article  PubMed  CAS  Google Scholar 

  7. Deshmukh SK, Agrawal SC. Degradation of human hair by some dermatophytes and other keratinolphilic fungi. Mycosen 1985; 28: 463–466.

    Article  CAS  Google Scholar 

  8. Malviya HK, Rajak RC, Hasija SK. In vitro degradation of hair keratin by Graphium penicilloides; Evidence for sulphytolysis and peptidolysis. Crypto Bot 1993; 3: 197–201.

    Google Scholar 

  9. Safranek WW, Goos RD. Degradation of wool by saprophytic fungi. Can J Microbiol 1982; 28:137–140.

    Article  CAS  Google Scholar 

  10. Chesters CGC, Matheson GE. The decomposition of wool by Keratinomyces ajelloi. Sabouraudia 1963; 2: 225–237.

    Google Scholar 

  11. Al-Musalam AA, Radwan SS. Wool-colonizing microorganisms capable of utilizing wool-lipids and fatty acids as sole sources of carbon and energy. J Appl Bacteriol 1990; 69: 806–813.

    Google Scholar 

  12. El-Naghy MA, El-Katany E, Fadl-Allah EM, Nazeer WW Degradation of chicken feathers by Chrysosporum georgiae. Mycopathologia 1998; 143: 77–84.

    Article  PubMed  CAS  Google Scholar 

  13. Kaul S, Sumbali G. Production of extracellular keratinase by keratinophilic fungal species inhabiting feathers of living poultry birds (Gallus domesticus): A comparison Mycopathologia 1999; 146: 19–24.

    CAS  Google Scholar 

  14. Muhsin TM, Aubaid AH, Al-Duboon AH. Extracellular enzyme activities of deramatophytes and yeast isolates on solid media. Mycoses 1997; 40: 465–469.

    Article  PubMed  CAS  Google Scholar 

  15. Lowry OH, Rosebrough NJ, Farr AL, Randall RJ. Protein measurement with the folin phenol reagent. J Biol Chem 1951; 193: 256–275.

    Google Scholar 

  16. Muhsin TM, AI-Rubaiy KK, Al-Duboon AH. Characteristics of dermatophytes in Basrah, Iraq. Mycoses 1999; 42: 335–338.

    Article  PubMed  CAS  Google Scholar 

  17. Aubaid AH, Muhsin TM. Partial purification and kinetic studies of exocellular proteinase from Trichophyton mentagrophytes var. erinacei. Mycoses 1998; 41: 163–168.

    PubMed  CAS  Google Scholar 

  18. Griffin DM. Fungal colonization of sterile hair in contact with soil. Trans Brit Mycol Soc 1960; 43: 583–596.

    Google Scholar 

  19. English MP. The saprophytic growth of non-keratinophilic fungi on keratinized substrate, and a comparison with keratinophilic fungi. Trans Brit Myco Soc 1965; 48: 219–235.

    Article  Google Scholar 

  20. Hasiji SK, Malviya H, Rajak RC. Keratinolytic ability of some fungi isolated from gelatin factory campus, Jabalpur (MP). Proc Nat Acad Sci India 1990; 3: 305–309.

    Google Scholar 

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Muhsin, T.M., Hadi, R.B. Degradation of keratin substrates by fungi isolated from sewage sludge. Mycopathologia 154, 185–189 (2002). https://doi.org/10.1023/A:1016335623534

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