Fungal decomposition of chicken-feather waste in submerged and solid-state fermentation

Abstract

Poultry industry is expanding rapidly and producing million tons of feather waste annually. Massive production of keratinaceous byproducts in the form of industrial wastes throughout the world necessitates its justified utilization. Chemical treatment of keratin waste is proclaimed as an eco-destructive approach by various researchers since it generates secondary pollutants. Keratinase released by a variety of microbes (bacteria and fungi) can be used for the effective treatment of keratin waste. Microbial degradation of keratin waste is an emerging and eco-friendly approach and offers dual benefits, i.e., treatment of recalcitrant pollutant (keratin) and procurement of a commercially important enzyme (keratinase). This study involves the isolation, characterization, and potential utility of fungal species for the degradation of chicken-feather waste through submerged and solid-state fermentation. The isolated fungus was identified and characterized as Aspergillus (A.) flavus. In a trial of 30 days, it was appeared that 74 and 8% feather weight was reduced through sub-merged and solid-state fermentation, respectively by A. flavus. The pH of the growth media in submerged fermentation was changed from 4.8 to 8.35. The exploited application of keratinolytic microbes is, therefore, recommended for the treatment of keratinaceous wastes to achieve dual benefits of remediation.

Structural characteristics and sound absorption properties of different kinds of waste feather fibers

“…The sound absorbing composite materials were prepared by using waste chicken feather fibers, waste duck feather fibers, and waste goose feather fibers as reinforcement materials and PBS as the matrix material. The physical parameters of the composites were as follows: the mass fraction of waste feather fibers was 40%, the length of waste feather fibers was 6.0 cm, the bulk density of the composites was 2.0 g/cm 3 , and the thickness of the composites was 10 mm. Each experiment was repeated five times, Figure 4 shows the average sound absorption coefficient curves of different kinds of waste feather fiber composites.…”

“…6 There is an urgent need to recover waste feather fibers in an efficient and high-value way. The most essential features of feather fibers are light mass, low density (0.97$0.99 g/cm 3 ), very low thermal conductivity, 7 water and moisture resistance, etc. Based on the unique structural characteristics of feather fibers, their structure with large hollow feather shafts and branches gives feathers unusual acoustic properties.…”

“…According to the survey, in the world, 1005 × 108 tons of meat were produced in 2020, and the global poultry industry can produce millions of tons of waste feather fibers each year. 2,3 The small number of down resources are mainly used by the traditional feather processing industry, the remaining feather resources are used to fill low-grade bedding and animal feed, etc., others that are not used are buried or incinerated. 4 Through the burial treatment of waste feather fibers may become a source of microbial pathogens, 5 which can easily cause diseases.…”