title: Production of feather hydrolysates with antioxidant, angiotensin-I converting enzyme- and dipeptidyl peptidase-IV-inhibitory activities.
abstract: The antioxidant and antihypertensive activities of feather hydrolysates obtained with the bacterium Chryseobacterium sp. kr6 were investigated. Keratin hydrolysates were produced with different concentrations of thermally denatured feathers (10-75 g l(-1)) and initial pH values (6.0-9.0). Soluble proteins accumulated in high amounts in media with 50 and 75 g l(-1) of feathers, reaching values of 18.5 and 22 mg ml(-1), respectively, after 48 hours of cultivation. In media with 50 g l(-1) of feathers, initial pH had minimal effect after 48 hours. Maximal protease production was observed after 24 hours of cultivation, and feather concentration and initial pH values showed no significant effect on enzyme yields at this time. Feather hydrolysates displayed in vitro antioxidant properties, and optimal antioxidant activities were observed in cultures with 50 g l(-1) feathers, at initial pH 8.0, after 48 hours growth at 30°C. Also, feather hydrolysates were demonstrated to inhibit the angiotesin I-converting enzyme by 65% and dipeptidyl peptidase-IV by 44%. The bioconversion of an abundant agroindustrial waste such as chicken feathers can be utilized as a strategy to obtain hydrolysates with antioxidant and antihypertensive activities. Feather hydrolysates might be employed as supplements in animal feed, and also as a potential source of bioactive molecules for feed, food and drug development.
authors.affiliation: Laboratório de Bioquímica e Microbiologia Aplicada, Instituto de Ciência e Tecnologia de Alimentos (ICTA), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre 91501-970, RS, Brazil.
authors.forename: Roberta
authors.initials: R
authors.lastname: Fontoura
authors.affiliation: Universidade Federal da Fronteira Sul (UFFS), Campus Cerro Largo, Cerro Largo 97900-000, RS, Brazil.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Daroit
authors.affiliation: Laboratório de Bioquímica e Microbiologia Aplicada, Instituto de Ciência e Tecnologia de Alimentos (ICTA), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre 91501-970, RS, Brazil.
authors.forename: Ana P F
authors.initials: AP
authors.lastname: Correa
authors.affiliation: Laboratório de Bioquímica e Microbiologia Aplicada, Instituto de Ciência e Tecnologia de Alimentos (ICTA), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre 91501-970, RS, Brazil.
authors.forename: Stela M M
authors.initials: SM
authors.lastname: Meira
authors.affiliation: Instituto de Ciencia y Tecnología de Alimentos y Nutrición (ICTAN, CSIC), C/José Antonio Nováis, 10. Ciudad Universitaria, Madrid 28040, Spain.
authors.forename: Mauricio
authors.initials: M
authors.lastname: Mosquera
authors.affiliation: Laboratório de Bioquímica e Microbiologia Aplicada, Instituto de Ciência e Tecnologia de Alimentos (ICTA), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre 91501-970, RS, Brazil. Electronic address: abrand@ufrgs.br.
authors.forename: Adriano
authors.initials: A
authors.lastname: Brandelli
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002645:Chickens; D045247:Chryseobacterium / Q000254:growth & development*; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; D005241:Feathers / Q000737:chemistry*; D006801:Humans; D007633:Keratins / Q000737:chemistry / Q000378:metabolism; D007703:Peptidyl-Dipeptidase A; D011492:Protein Hydrolysates / Q000737:chemistry / Q000378:metabolism
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D000975:Antioxidants; D011492:Protein Hydrolysates; D007633:Keratins; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; D007703:Peptidyl-Dipeptidase A