Biodegradation of wool waste and keratinase production in scale-up fermenter with different strategies by Stenotrophomonas maltophilia BBE11-1

Abstract

A keratin-degrading strain Stenotrophomonas maltophilia BBE11-1 was grown in a 3-L batch fermenter containing wool waste as the main medium and cell growth rate was determined as the key factor to affect keratinase yield. Three strategies of temperature-shift procedure, two-stage DO control and fed-batch process were used to change growth rate. And a 62.2% improvement of keratinase yield was achieved. With the glucose fed-batch procedure in 30-L fermenter, keratinase production was significantly improved up to 117.7% (1728 U/ml) as compared with initial data (793.8 U/ml) in a 3-L fermenter and with much shortened fermentation time within 18 h. Significant structure changes and high levels of free amino acids from wool decomposition indicated the possible applications for wool waste management and fertilizer industry. The remarkable digestion of wool cuticle also suggested its potential utilization in textile industry.

Green Hydrolysis as an Emerging Technology to Turn Wool Waste into Organic Nitrogen Fertilizer

“…Fang et al [21] grew a keratin-degrading strain Stenotrophomonas maltophilia in a batch fermenter containing wool waste as the main medium and cell growth rate was determined as the key factor to affect keratinase yield. Significant structure changes and high levels of free amino acids from wool decomposition indicated the possible applications for wool waste management and fertilizer industry.…”

Novel heterogeneous photocatalysts prepared with waste wool and Fe3+ or Cu2+ ions for degradation of CI Reactive Red 195: a comparative study

“…Moreover, reclaimed wool textiles such as apparel, blankets, and footcloths from developed areas are another important source of waste wool fibre. Over the past decade, a few studies have reported the use of waste wool as a protein resource for keratinase production [29] or as an adsorbent to remove metal ions from industrial effluent [25,30]. Moreover, organic compounds digested from waste wool may provide desirable nutritional conditions for germ propagation [25,26].…”

Biochemical characterization of an extreme alkaline and surfactant-stable keratinase derived from a newly isolated actinomycete Streptomyces aureofaciens K13

“…2,3 Thus, the hydrolysis reaction of keratin is not easily performed due to the disulde bonds. 1,2 These keratin wastes are important resources containing valuable proteins and amino acids.…”