Inhibiting pancreatic Lipase(PL)and cholesterol esterase(CEase)can effectively control blood triglycerides and cholesterol levels.The interaction characteristics of pentacyclic triterpenoid acids(oleanolic acid[OA],ur...Inhibiting pancreatic Lipase(PL)and cholesterol esterase(CEase)can effectively control blood triglycerides and cholesterol levels.The interaction characteristics of pentacyclic triterpenoid acids(oleanolic acid[OA],ursolic acid[UA],and corosolic acid[CA])with PL and CEase were studied by inhibition kinetics,multispectroscopy,and molecular docking methods.Enzyme inhibition and inhibition kinetics showed that pentacyclic triterpenoid acids effectively inhibited PL and CEase in a competitive manner with IC50 values ranging from 0.077 mg/mL to 0.446 mg/mL.UV-Vis,fourier transform infrared,fluorescence quenching,and circular dichroism analysis demonstrated that OA,UA,and CA disrupted the conformation of PL and CEase through hydrogen bonding and hydrophobic forces,resulting in loose protein structures.Molecular docking analysis revealed that pentacyclic triterpenoid acids could stably bind at key residues in the active site of PL and CEase.Molecular dynamics(MD)simulation further confirmed the stable binding of pentacyclic triterpene acids to PL and CEase.This study suggested that OA,UA,and CA could have an essential value as digestive enzyme inhibitors.展开更多
The'Hayward'kiwifruit is extremely susceptible to chilling injury(CI)during the late stages of cold storage,thus limiting its storage quality and life.Therefore,mitigating the losses caused by CI is imperative...The'Hayward'kiwifruit is extremely susceptible to chilling injury(CI)during the late stages of cold storage,thus limiting its storage quality and life.Therefore,mitigating the losses caused by CI is imperative.Salicylic acid(SA)has been demonstrated to mitigate CI in fruit and vegetables.In this study,we conducted a comparative analysis of proline metabolism,key endogenous hormone levels,as well as the effects on cell structure and membrane lipid oxidation in kiwifruit treated with 1 mM SA during low-temperature storage.The results showed that SA could attenuate lipoxygenase(LOX)activity,enhance catalase(CAT)activity,suppress the elevation of malondialdehyde(MDA)content,mitigate starch granule degradation in cells,and preserve cell structure integrity.Moreover,SA was found to enhance proline biosynthesis by activating ornithine transaminase(OAT)and pyrroline-5-carboxylate synthase(P5CS)while concurrently suppressing proline dehydrogenase(PDH)activity.Additionally,exogenous SA increased endogenous levels of both SA and abscisic acid(ABA),while simultaneously decreasing the concentration of gibberellic acid(GA)in fruit.In conclusion,exogenous SA treatment could alleviate the development of CI in kiwifruit by maintaining cell structure,promoting proline synthesis,and balancing endogenous hormone content.Our study offers a theoretical foundation for understanding the mechanism by which SA mitigates cold damage in kiwifruit,and provides novel insights into the low-temperature preservation of kiwifruit.展开更多
基金support from the National Key R&D Program of China(2019YFD1002404).
文摘Inhibiting pancreatic Lipase(PL)and cholesterol esterase(CEase)can effectively control blood triglycerides and cholesterol levels.The interaction characteristics of pentacyclic triterpenoid acids(oleanolic acid[OA],ursolic acid[UA],and corosolic acid[CA])with PL and CEase were studied by inhibition kinetics,multispectroscopy,and molecular docking methods.Enzyme inhibition and inhibition kinetics showed that pentacyclic triterpenoid acids effectively inhibited PL and CEase in a competitive manner with IC50 values ranging from 0.077 mg/mL to 0.446 mg/mL.UV-Vis,fourier transform infrared,fluorescence quenching,and circular dichroism analysis demonstrated that OA,UA,and CA disrupted the conformation of PL and CEase through hydrogen bonding and hydrophobic forces,resulting in loose protein structures.Molecular docking analysis revealed that pentacyclic triterpenoid acids could stably bind at key residues in the active site of PL and CEase.Molecular dynamics(MD)simulation further confirmed the stable binding of pentacyclic triterpene acids to PL and CEase.This study suggested that OA,UA,and CA could have an essential value as digestive enzyme inhibitors.
基金gratitude to The Key Research and Development Program in Shaanxi Province(2018ZDXM-NY-056)for providing us with financial support.
文摘The'Hayward'kiwifruit is extremely susceptible to chilling injury(CI)during the late stages of cold storage,thus limiting its storage quality and life.Therefore,mitigating the losses caused by CI is imperative.Salicylic acid(SA)has been demonstrated to mitigate CI in fruit and vegetables.In this study,we conducted a comparative analysis of proline metabolism,key endogenous hormone levels,as well as the effects on cell structure and membrane lipid oxidation in kiwifruit treated with 1 mM SA during low-temperature storage.The results showed that SA could attenuate lipoxygenase(LOX)activity,enhance catalase(CAT)activity,suppress the elevation of malondialdehyde(MDA)content,mitigate starch granule degradation in cells,and preserve cell structure integrity.Moreover,SA was found to enhance proline biosynthesis by activating ornithine transaminase(OAT)and pyrroline-5-carboxylate synthase(P5CS)while concurrently suppressing proline dehydrogenase(PDH)activity.Additionally,exogenous SA increased endogenous levels of both SA and abscisic acid(ABA),while simultaneously decreasing the concentration of gibberellic acid(GA)in fruit.In conclusion,exogenous SA treatment could alleviate the development of CI in kiwifruit by maintaining cell structure,promoting proline synthesis,and balancing endogenous hormone content.Our study offers a theoretical foundation for understanding the mechanism by which SA mitigates cold damage in kiwifruit,and provides novel insights into the low-temperature preservation of kiwifruit.
