In Vitro Antibacterial Properties Of Proanthocyanidin Extracts From Aronia Melanocarpa And Its Microemulsion Preparation

Objective: Aronia melanocarpa,also known as black-fruited glandular rowan,is rich in nutrients and contains a large number of flavonoids,proanthocyanidins,and polysaccharides,which have various health functions such as anti-inflammatory,antibacterial,anti-radiation,hypoglycemic,and hepatoprotective properties.In this paper,we conducted an exploratory study on the extraction and purification process,in vitro antibacterial activity and preparation and characterization of microemulsion of proanthocyanidins from Liriodendron nigrum to support the subsequent research of Liriodendron nigrum.Methods: In this study,proanthocyanidins were extracted from Liriodendron nigrum,and the crude extract was determined by hydrochloric acid-n-butanol method to obtain proanthocyanidins.The crude extract of proanthocyanidins was optimized by macroporous resin to obtain the proanthocyanidin extract of Liriodendron chinense.The extracts were then subjected to in vitro antibacterial activity and microemulsion preparation studies.Results: 1.The purification process of proanthocyanidins from Liriodendron niger was determined: 5.15 mg/m L of crude proanthocyanidin extract was sampled at a flow rate of3 m L/min in an AB-8 macroporous resin column with a determined diameter-to-height ratio of 1:30,and 80 ml of 80% ethanol was used for elution to obtain proanthocyanidin extract of Liriodendron niger with a purity of about 87.78%.2.The inhibitory effect of proanthocyanidin extract of L.nigra on S.aureus was greater than that on E.coli,as well as the MIC value of 50 μg/ml for S.aureus.3.Polyethylene glycol glycerol oleate as the oil phase,distilled water as the aqueous phase,polyethylene glycol glycerol caprylate as the surfactant,isopropyl alcohol as the co-surfactant,Km=2:1 and water content of 60%were used as The prescription of the blank microemulsion and the maximum drug loading was 8.53 mg/m L.4.The stability,particle size,PDI,light transmission and electrical conductivity of the drug loaded microemulsion met the pharmacopeial standards and the microemulsion was spherical with smooth surface as observed by transmission electron microscopy.Conclusions: In this study,the optimization process of the macroporous resin of L.nigra procyanidins was determined,and the in vitro antibacterial effect of L.nigra procyanidins was demonstrated.The optimization of the prescription of proanthocyanidins microemulsion of Liriodendron nigrum and the characterization study of the drug-laden microemulsion provide the basis for the subsequent study of proanthocyanidins of Liriodendron nigrum.