摘要
Abstract
Deterioration of the oral microecological environment is a major contributor to oral odor in dogs,the key to alleviation lies in inhibiting the growth of harmful bacteria in the oral cavity,particularly Streptococcus mutans.In this study,composite antibacterial phospholipid liposomes(CAPL)were formulated by encapsulating ε-polylysine hydrochloride,nisin,and tea polyphenols within phospholipid-based liposomes.The 50%inhibitory concentration(IC50)of CAPL against Streptococcus mutans was measured,and a mouse acute toxicity test was conducted to evaluate safety.A feeding trial in dogs was then performed to assess the impact of CAPL on dental plaque rate,saliva secretion quantity,saliva antibacterial capacity,oral microbiota,oral odor scores,and levels of sulphide and ammonia.The results showed that CAPL had an IC50 of 19.93 mg/mL against S.mutans,which was 53.79%lower than that of the non-encapsulated antibacterial phospholipid(IC₅₀:43.13 mg/mL).A dose of 1.2 g/(kg·bw)was confirmed to be within a safe range.After 4 days of feeding,dogs in the Test group had significantly improved saliva antibacterial capacity compared to the Control group(P<0.05),reaching 4.85 times that of the Control group and 1.24 times that of the Normal group.After 8 days,the dental plaque rate in the Test group showed no significant difference from the Normal group(P>0.05),but was 86.50%lower than that of the Control group(P<0.05).The oral odor elimination rate reached 93.33%.At 12 days,saliva secretion quantity,sulphide,and ammonia levels in the Test group were not significantly different from the Normal group(P>0.05);however,sulphide were reduced by 63.83%and ammonia by 82.04%compared to the Control group(P<0.05).After 20 days,the relative abundance of Streptococcus spp.in the oral cavity decreased from 9.29%to 2.24%.These results demonstrate that CAPL significantly improves oral antibacterial defense and effectively reduces canine oral odor.关键词
口腔异味/ε-聚赖氨酸盐酸盐/乳酸链球菌素/茶多酚/卵磷脂脂质体Key words
oral odor/ε-polylysine hydrochloride/nisin/tea polyphenols/phospholipid liposomes分类
农业科技
