Keratinolytic potential of Pseudomonas aeruginosa strain SDS3 has been evaluated for the metabolism of chicken feathers. Results indicated that strain SDS3 showed complete metabolism of 0.1 and 0.5% (w/v) chicken feathers in minimal medium. Feathers were metabolized up to 80% at 1% (w/v) concentration. Maximum soluble protein ( ？μg/mL) and keratinase ( ？U/mL) were observed in the presence of 1% chicken feathers after five days of incubation. The effect of carbon and nitrogen sources showed that feather degradation was stimulated by complex carbon/nitrogen sources such as starch, malt extract, tryptone, and beef extract and was inhibited by simple carbon and nitrogen sources. Electricity production by employing chicken feathers as a substrate in microbial fuel cell (MFC) was evaluated. It was observed that maximum voltage corresponding to 141？mV was observed after 14 days of incubation. Maximum power density of 1206.78？mW/m2 and maximum current density of 8.6？mA/m2 were observed. The results clearly indicate that chicken feathers can be successfully employed as a cheap substrate for electricity production in MFC. This is the first report showing employment of chicken feathers as substrate in MFC. 1. Introduction Feathers constitute the major bulk of biological waste generated by local butchers and poultry processing industries in India [1]. According to a recent report of USDA, annual consumption of poultry in India was 2.3 million tons in 2010 and it is expected to increase at a tremendous rate. Due to poor management of waste, the by-products of poultry industry (especially feathers) have become one of the major pollutants due to their recalcitrant nature [1, 2]. About 90% of feathers consist of keratin, which is a fibrous and insoluble structural protein consisting of β-helical coils joint together by disulfide linkages [3]. This structural feature enables it to resist adverse environmental conditions and degradation by proteases [4]. Therefore, feathers are considered as a biological waste and cause serious environmental problems. However, feathers are considered a good source of essential amino acids [5] but due to their stable structure, feathers cannot be employed as a source of proteins and free amino acids in their native form and requires processing to release amino acids and peptides [6]. The most commonly used method for feather disposal is incineration [7] and degradation by chemical methods [8]. These methods cause significant reduction in amino acid content of feathers and reduce the overall quality of proteins [7]. Biodegradation of
References
[1]
A. A. Khardenavis, A. Kapley, and H. J. Purohit, “Processing of poultry feathers by alkaline keratin hydrolyzing enzyme from Serratia sp. HPC 1383,” Waste Management, vol. 29, no. 4, pp. 1409–1415, 2009.
[2]
L. Manczinger, M. Rozs, C. Vágv？lgyi, and F. Kevei, “Isolation and characterization of a new keratinolytic Bacillus licheniformis strain,” World Journal of Microbiology and Biotechnology, vol. 19, no. 1, pp. 35–39, 2003.
[3]
N. M. R. Da Gioppo, F. G. Moreira-Gasparin, A. M. Costa, A. M. Alexandrino, C. G. M. De Souza, and R. M. Peralta, “Influence of the carbon and nitrogen sources on keratinase production by Myrothecium verrucaria in submerged and solid state cultures,” Journal of Industrial Microbiology and Biotechnology, vol. 36, no. 5, pp. 705–711, 2009.
[4]
R. Gupta and P. Ramnani, “Microbial keratinases and their prospective applications: an overview,” Applied Microbiology and Biotechnology, vol. 70, no. 1, pp. 21–33, 2006.
[5]
B. S. Harrap and E. F. Woods, “Soluble derivatives of feather keratin. 1. Isolation, fractionation and amino acid composition,” Biochemical Journal, vol. 92, no. 1, pp. 8–18, 1964.
[6]
A. A. Onifade, N. A. Al-Sane, A. A. Al-Musallam, and S. Al-Zarban, “A review: potentials for biotechnological applications of keratin-degrading microorganisms and their enzymes for nutritional improvement of feathers and other keratins as livestock feed resources,” Bioresource Technology, vol. 66, no. 1, pp. 1–11, 1998.
[7]
M. C. Papadopoulos, A. R. El Boushy, A. E. Roodbeen, and E. H. Ketelaars, “Effects of processing time and moisture content on amino acid composition and nitrogen characteristics of feather meal,” Animal Feed Science and Technology, vol. 14, no. 3-4, pp. 279–290, 1986.
[8]
C. G. Cai, B. G. Lou, and X. D. Zheng, “Keratinase production and keratin degradation by a mutant strain of Bacillus subtilis,” Journal of Zhejiang University B, vol. 9, no. 1, pp. 60–67, 2008.
[9]
A. Hadas and L. Kautsky, “Feather meal, a semi-slow-release nitrogen fertilizer for organic farming,” Fertilizer Research, vol. 38, no. 2, pp. 165–170, 1994.
[10]
B. E. Logan, “Biologically extracting energy from wastewater: biohydrogen production and microbial fuel cells,” Environmental Science and Technology, vol. 38, no. 9, pp. 160–167, 2004.
[11]
B. E. Logan and J. M. Regan, “Microbial fuel cells: challenges and applications,” Environmental Science and Technology, vol. 40, no. 17, pp. 5172–5180, 2006.
[12]
Y. Lin and S. Tanaka, “Ethanol fermentation from biomass resources: current state and prospects,” Applied Microbiology and Biotechnology, vol. 69, no. 6, pp. 627–642, 2006.
[13]
D. Saaris, Y. Kotseridis, M. Linga, M. Galiotou-Panayotou, and S. Papanikolaou, “Enhanced ethanol production, volatile compound biosynthesis and fungicide removal during growth of a newly isolated Saccharomyces cerevisiae strain on enriched pasteurized grape musts,” Engineering in Life Sciences, vol. 9, no. 1, pp. 29–37, 2009.
[14]
K. Rabaey, W. Ossieur, M. Verhaege, and W. Verstraete, “Continuous microbial fuel cells convert carbohydrates to electricity,” Water Science and Technology, vol. 52, no. 1-2, pp. 515–523, 2005.
[15]
B. Min, J. R. Kim, S. E. Oh, J. M. Regan, and B. E. Logan, “Electricity generation from swine wastewater using microbial fuel cells,” Water Research, vol. 39, no. 20, pp. 4961–4968, 2005.
[16]
S. A. Patil, V. P. Surakasi, S. Koul et al., “Electricity generation using chocolate industry wastewater and its treatment in activated sludge based microbial fuel cell and analysis of developed microbial community in the anode chamber,” Bioresource Technology, vol. 100, no. 21, pp. 5132–5139, 2009.
[17]
K. P. Katuri, A. Enright, V. O'Flaherty, and D. Leech, “Microbial analysis of anodic biofilm in a microbial fuel cell using slaughterhouse wastewater,” Bioelectrochemistry, vol. 87, pp. 164–171, 2012.
[18]
V. Chaturvedi and A. Kumar, “Diversity of culturable sodium dodecyl sulfate (SDS) degrading bacteria isolated from detergent contaminated ponds situated in Varanasi city, India,” International Biodeterioration and Biodegradation, vol. 65, no. 7, pp. 961–971, 2011.
[19]
E. Bach, D. J. Daroit, A. P. F. Corrêa, and A. Brandelli, “Production and properties of keratinolytic proteases from three novel Gram-negative feather-degrading bacteria isolated from Brazilian soils,” Biodegradation, vol. 22, no. 6, pp. 1191–1201, 2011.
[20]
A. De Logu, P. Uda, M. L. Pellerano, M. C. Pusceddu, B. Saddi, and M. L. Schivo, “Comparison of two rapid colorimetric methods for determining resistance of Mycobacterium tuberculosis to rifampin, isoniazid, and streptomycin in liquid medium,” European Journal of Clinical Microbiology and Infectious Diseases, vol. 20, no. 1, pp. 33–39, 2001.
[21]
M. M. Bradford, “A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein dye binding,” Analytical Biochemistry, vol. 72, no. 1-2, pp. 248–254, 1976.
[22]
K. Wawrzkiewicz, J. Lobarzewski, and T. Wolski, “Intracellular keratinase of Trichophyton gallinae,” Journal of Medical and Veterinary Mycology, vol. 25, no. 4, pp. 261–268, 1987.
[23]
R. M. Tomarelli, J. Charney, and M. L. Harding, “The use of azoalbumin as a substrate in the colorimetric determination,” The Journal of Laboratory and Clinical Medicine, vol. 34, no. 3, pp. 428–433, 1949.
[24]
D. J. Daroit, A. P. F. Corrêa, and A. Brandelli, “Keratinolytic potential of a novel Bacillus sp. P45 isolated from the Amazon basin fish Piaractus mesopotamicus,” International Biodeterioration and Biodegradation, vol. 63, no. 3, pp. 358–363, 2009.
[25]
J. H. Jeong, Y. D. Jeon, O. M. Lee et al., “Characterization of a multifunctional feather-degrading Bacillus subtilis isolated from forest soil,” Biodegradation, vol. 21, no. 6, pp. 1029–1040, 2010.
[26]
B. Hou, Y. Hu, and J. Sun, “Performance and microbial diversity of microbial fuel cells coupled with different cathode types during simultaneous azo dye decolorization and electricity generation,” Bioresource Technology, vol. 111, pp. 105–110, 2012.
[27]
R. Sharma and R. Gupta, “Substrate specificity characterization of a thermostable keratinase from Pseudomonas aeruginosa KS-1,” Journal of Industrial Microbiology and Biotechnology, vol. 37, no. 8, pp. 785–792, 2010.
[28]
A. P. F. Corrêa, D. J. Daroit, and A. Brandelli, “Characterization of a keratinase produced by Bacillus sp. P7 isolated from an Amazonian environment,” International Biodeterioration and Biodegradation, vol. 64, no. 1, pp. 1–6, 2010.
[29]
H. J. Son, H. C. Park, H. S. Kim, and C. Y. Lee, “Nutritional regulation of keratinolytic activity in Bacillus pumilis,” Biotechnology Letters, vol. 30, no. 3, pp. 461–465, 2008.
[30]
P. Kaewkannetra, T. Imai, F. J. Garcia-Garcia, and T. Y. Chiu, “Cyanide removal from cassava mill wastewater using Azotobactor vinelandii TISTR 1094 with mixed microorganisms in activated sludge treatment system,” Journal of Hazardous Materials, vol. 172, no. 1, pp. 224–228, 2009.
[31]
S. Venkata Mohan, R. Saravanan, S. V. Raghavulu, G. Mohanakrishna, and P. N. Sarma, “Bioelectricity production from wastewater treatment in dual chambered microbial fuel cell (MFC) using selectively enriched mixed microflora: effect of catholyte,” Bioresource Technology, vol. 99, no. 3, pp. 596–603, 2008.
