刺梨纳米囊泡的制备、表征及其抗氧化、降血糖与抗毒溶血活性研究OA

To deeply investigate the structural characteristics and activities of nanovesicles derived from Rosa roxburghii Tratt.(RDNs),they were isolated,extracted,and characterized.Additionally,their antioxidant,hypoglycemic,and anti-hemolytic activities against Staphylococcus aureus exotoxin were explored.The RDNs were isolated using ultracentrifugation,and their morphology was characterized through transmission electron microscopy(TEM).The protein,lipid,and RNA composition/concentrations were quantified employing the BCA assay,thin-layer chromatography(TLC),and RNA extraction kits,respectively.The antioxidant capacity was assessed using DPPH and ABTS+radical scavenging assays,while the hypoglycemic activity was evaluated through α-glucosidase and α-amylase inhibition assays.Using 2%rat erythrocytes as the research object,the experiment was divided into blank control group,positive control group,S.aureus-EVs group,RDNs group,and RDNs+S.aureus-EVs group,and in vitro anti-hemolytic rate of RDNs was detected.The results indicated that RDNs had an average hydrodynamic diameter of 155.27±1.39 nm,a Zeta potential of −8.60±0.64 mV,and maintained stability at −80℃for 12 days.The particles remained stable during the first 6 days of storage at 4℃,but exhibited significant particle size changes after surpassing the 6-day mark(P<0.01).Particle size remained unchanged(P>0.05)at pH1.2,while pH6.5 showed significant change in particle size(P<0.05).Biochemical analysis uncovered the presence of protein(5.50±0.00 mg/mL),lipid(4.23±0.40 mg/mL),and RNA(3.91±1.97 μg/mL).Notably,protein bands were observed at 24,50~70,and 70 kDa.Lipid components exhibited an intricate composition,which included phytosterols and lecithins.Concentration-dependent(0~212.30 mg/mL)scavenging of DPPH and ABTS+radicals was observed,with the half-inhibitory concentrations(IC50)for the two radicals being 112.90 and 64.38 mg/mL,respectively.Additionally,when the concentration reached 212.30 mg/mL,the RDNs were capable of eliminating 99.80%of ABTS+.The α-glucosidase and α-amylase inhibition rates were 48%and 21%,respectively,significantly lower than positive controls(P<0.01).The hemolysis rates were nearly 0 in the RDNs group,64%in the S.aureus-EVs group,and 8%in the RDNs+S.aureus-EVs group,which was significantly lower than that in the S.aureus-EVs group(P<0.01).The RDNs had antioxidant and hypoglycemic activities and could exert anti-hemolytic effects against S.aureus exotoxins,laying a foundation for their potential applications in the fields of antioxidants and natural antibacterial agents.