Whey protein concentrate-80(WPC-80)fermented with L.fermentum(KGL4)(37℃)and S.cerevisiae(WBS2A)(25℃)was tested for ACE-inhibitory and antioxidant activities over different periods(12,24,36 and 48 h).Proteolytic acti...Whey protein concentrate-80(WPC-80)fermented with L.fermentum(KGL4)(37℃)and S.cerevisiae(WBS2A)(25℃)was tested for ACE-inhibitory and antioxidant activities over different periods(12,24,36 and 48 h).Proteolytic activity(OPA method)was used to optimize the growth conditions(inoculation rate,i.e.at 1.5%,2.0%,and 2.5%and incubation time,i.e.12,24,36,and 48 h)for peptide production.Results indicated that the highest amount of peptides was obtained at 7.24 mg/mL for KGL4(37℃,48 h)and 8.59 mg/mL for WBS2A(25℃,48 h).The whey protein fermentate inhibited the LPS-induced NO production,while enhanced production concentrations of TNF-α,IL-6,and IL-1β.Subsequently,SDS-PAGE,as well as Two-Dimensional(2D)gel electrophoresis methods,were applied for protein purification using water-soluble extracts(WSEs)of WPC-80 fermented by a combination of L.fermentum and S.cerevisiae.On SDS-PAGE,protein bands were observed in the range of 10-55 kDa,whereas on the 2D page,protein spots were in the range of 10-70 kDa.All the 2D spots were analyzed using RPLC/MS.WSEs of 3 kDa and 10 kDa permeates were used in RP-HPLC to identify distinct peptide fractions.The data from LC/MS was also characterized by utilizing ProteinPilot software.Further,different functional groups were also analyzed using FTIR investigation.The research aims to isolate and characterize novel ACE-inhibitory and antioxidative peptides from fermented WPC-80 produced by Lactobacillus fermentum and S.cerevisiae.展开更多
文摘Whey protein concentrate-80(WPC-80)fermented with L.fermentum(KGL4)(37℃)and S.cerevisiae(WBS2A)(25℃)was tested for ACE-inhibitory and antioxidant activities over different periods(12,24,36 and 48 h).Proteolytic activity(OPA method)was used to optimize the growth conditions(inoculation rate,i.e.at 1.5%,2.0%,and 2.5%and incubation time,i.e.12,24,36,and 48 h)for peptide production.Results indicated that the highest amount of peptides was obtained at 7.24 mg/mL for KGL4(37℃,48 h)and 8.59 mg/mL for WBS2A(25℃,48 h).The whey protein fermentate inhibited the LPS-induced NO production,while enhanced production concentrations of TNF-α,IL-6,and IL-1β.Subsequently,SDS-PAGE,as well as Two-Dimensional(2D)gel electrophoresis methods,were applied for protein purification using water-soluble extracts(WSEs)of WPC-80 fermented by a combination of L.fermentum and S.cerevisiae.On SDS-PAGE,protein bands were observed in the range of 10-55 kDa,whereas on the 2D page,protein spots were in the range of 10-70 kDa.All the 2D spots were analyzed using RPLC/MS.WSEs of 3 kDa and 10 kDa permeates were used in RP-HPLC to identify distinct peptide fractions.The data from LC/MS was also characterized by utilizing ProteinPilot software.Further,different functional groups were also analyzed using FTIR investigation.The research aims to isolate and characterize novel ACE-inhibitory and antioxidative peptides from fermented WPC-80 produced by Lactobacillus fermentum and S.cerevisiae.
