Antibacterial Activity Of Hydrolyzed Product Of Pectin And Its Effect On Intestinal Health Of Broilers

The purpose of this study was to investigate the antibacterial properties of pectin hydrolysis product and its effects on growth performance and intestinal health of broilers.Firstly,the optimum temperature and p H of pectinase hydrolysis reaction were50℃ and 5.Based on the inhibition zone,inhibitory concentration and cell membrane integrity.The antibacterial activity of 20 g/L pectin hydrolysis product with different doses of 20 g/L,40 g/ L,80 g/L,120 g/L and 160 g/L was explored under the optimum conditions.In order to further study the effect of pectin hydrolysis product on growth performance and intestinal health of broilers,84 yellow feathered broilers with similar body weight and good health status were selected and randomly divided into 7 treatment groups(A,B,C,D,E,F and G),with 6 replicates in each group and 2 broilers in each replicate.24 hours a day,fluorescent lamp irradiation,free drinking water.The broilers were treated by gavage at9:00 and 21:00 every day.The samples were collected on the 14 th day.Group A was the control group.Group A,B,C,D and E were fed with basal diet and gavage with normal saline,20 g/L pectin and pectin hydrolysis product with different pectinase doses of 20 g/L,80 g/L and 160 g/L,respectively.Groups F and G were both gavage with 20 g/L pectin.Group F and G were fed with basal diets adding with 500 mg/kg pectinase and 1000 mg/kg pectinase respectively.The body weight and feed intake of broilers were recorded every day,and the average daily gain and average daily feed intake were calculated.At the end of the experiment,1 broilers with body weigh similar to average weight of the treatment group in each replicate were selected for slaughter.The heart,liver,lung,kidney and other organs,spleen,thymus,bursa of Fabricius and other immune organs were completely stripped,weighed and calculated Organ index.All parts of the digestive tract were took out intactly,then the p H of the duodenum,jejunum,ileum,and cecum were measured by a precision acid meter.The villus height and crypt depth and the ratio of villus height/crypt depth of jejunum slice were measured.The intestinal morphology and barrier gene expression abundance of duodenum and jejunum tissue were measured.The results are as follows:1.Compared with the control group,the ability of pectin hydrolysis product of different doses to inhibit bacterial growth and destroy the integrity of bacterial cell membranes to release protein nucleic acids increased with the increase of pectinase dose,which reached a peak at the dose of 120g/L.2.Compared with group A,the final weights of broilers of group D,E and G were increased by 6.13%,3.51% and 3.15% respectively,group D is significantly different(P <0.05).The average daily feed intake of group C and D were significantly increased by18.90% and 12.55% respectively(P < 0.05).The average daily gain of group C,D,E and G were increased.While group D increased by 14.21% compared with the group A(P < 0.05).Except for group C,E the ratio of feed/gain of the other groups were reduced,while group F was reduced by 10.70%(P < 0.05).3.Compared with group A,the spleen index of broilers in each group increased but without significant difference.The thymus index of each treatment group was higher,while group C and G were significantly increased by 33.39% and 35.29%(P < 0.05).4.Compared with group A,the p H of duodenum of group F was decreased by 4.96%(P < 0.05).The p H of jejunum of group D was decreased by 9.3%(P < 0.05).The p H of cecum of group B was increased by 4.26%(P < 0.05).There were no significant differences in the p H values of the duodenum,jejunum,ileum and cecum in the other test groups.5.Compared with group A,except for group C and E,the values of the villus height in other treatment groups were higher,while group G were significantly increased by35.2% respectively(P < 0.05).The values of crypt depth in all treatment groups were significantly decreased by 14.92%,13.58%,21.45%,18.61%,12.23%,respectively.The ratio of villus height/crypt depth of group E,F and G were significantly increased by32.35%,29.63% and 54.66%,respectively(P < 0.05).6.Compared with A,the relative expression of ZO-1,Occludin m RNA of duodenum and jejunum increased in each treatment group.The relative expression of ZO-1 m RNA of duodenum significantly increased in group C,D and E(P < 0.05),while the relative expression Occludin m RNA of duodenum significantly increased in group F(P < 0.05).The relative expression of ZO-1 m RNA of jejunum significantly increased in group F and G(P < 0.05),while the relative expression Occludin m RNA of duodenum significantly increased in group C,F and G(P < 0.05).In summary,the pectin hydrolysis product can destroy the integrity of the bacterial cell membrane and inhibit the growth of pathogenic bacteria.The optimal dose of pectinase is120 g/L.The optimal reaction conditions are 50℃,p H = 5.In vivo experiments further found that the pectin hydrolysis product can promote the growth of immune organs,reduce the p H of the intestine,improve the morphology of the intestine,adjust the physical and chemical barrier of the intestine,and thereby improve the growth performance of yellow feather broilers.