PRODUCTION OF PEPTONE FROM ALKALINE AND ACIDIC HYDROLYSIS OF CHICKEN FEATHER KERATIN AND USE IT AS AN ALTERNATIVE SOURCE OF NITROGEN TO PREPARE SOME CULTURE MEDIA

Abstract

The study aimed to reduce environmental pollution caused by chicken waste and exploit the high concentration of keratin in it, and analyze alkaline and acidic, and using it in preparing expensive peptone and using it as an alternative to nitrogen sources in some culture media to grow some microorganisms. The alkaline and acidic hydrolysis process of white chicken feather powder was applied using different concentrations of sodium hydroxide(NaOH) and hydrochloric acid (HCL).The results showed that the highest percentage of keratin was (81.2, 72)% when using the NaOH and HCL at a concentration of 4 molar. However, the highest degree of hydrolysis (35, 28)% for the NaOH and HCL prepared at a concentration of (2 and 3) molar respectively. The highest solubility was (48, 38)% and water holding capacity (3.1, 2.2) g/g respectively. The NaOH and HCL gave the highest solubility were used in preparing the modified Nutrient agar and MacConky agar media by replacing the nitrogen sources in them with these hydrolysates. The numbers of Bacillus subtilis (B.subtilis)  reached (105, 87, 77) × 10⁵C.F.U/ml. and Staphylococcus aureus (S.aureus). (95, 75, 64) × 10⁵C.F.U/ml. using the commercial Nutrient agar and the modified media using the alkaline and acidic hydrolysates, while the numbers of Escherichia coli(E.coli) reached (69, 51, 42)× 10⁵C.F.U/ml. and Salmonella typhi (S.typhi)(46, 36, 27)×10⁵C.F.U/ml. on the commercial MacConky agar modified with the alkaline and acidic hydrolysates.