| Infant food safety has always been a hot topic.As one of the infant’s main source of food,powdered infant formula(PIF)safety problems often occur.The main hazards of PIF are biological hazards,chemical hazards and physical hazards,microbial contamination which is the most extensive and the greatest impact caused great harm on babies’ health.Clostridium botulinum,Clostridium sporogenes and other Clostridium contamination has shown up several times recent years causing people panic.Breast milk as a natural ideal infant food similarly,not only can provide essential nutrients for infants,but also can inhibit the growth of Gram-positive bacteria and most pathogens,and improve the antibacterial,anti-infective ability of baby’s intestinal tract because of its bacteriostatic bioactive substances.So this study sample the infant feces and PIF,isolate and identify the Clostridium,obtain the contamination data on infants and PIF.And compare the anti-infection of Clostridium between breastfeeding and formula feeding.This study select Jian Guo Community Health Center,Cheng Gaozi Community Health Center and Li Ming Community Health Center in Harbin as sampling sites.Sampling market-saling PIF,0-1 year old breast-fed infant feces,0-1 year old formula-fed infant feces and infant daily consumed PIF(DPIF).The samples were cultured in meat culture medium and inoculated in Colombian Blood Agar Plate,then cultured and isolated the pure cultures.Selecting the typical Clostridium colonies on the plate,gram strain and microscopic the colonies’ morphological characteristics.Typical sample strains were identified by using API 20A Identification system,VITEK 2 Compact,and 16S rRNA sequencing.This study was totally collected 191 samples,including 20 market-saling PIF samples,1160-1 year old infant feces and 55 DPIF samples.Of these,10(5.24%)samples were detected for Clostridium.There is no Clostridium detected among market-saling PIF samples;7 samples are detected Clostridium among infant feces,of which 3 isolates were identified as C.Sporogenes,2 isolates of C.Tertium,2 isolates of C.Sordelli.3 samples are detected Clostridium among DPIF,of which 1 isolate was identified as C.Sporogenes,2 isolates of C.Butyricum.The detection rate of Clostridium was 0 in breast-fed infant feces,and the detection rate of C.Sporogenes in formula-fed infant feces was 5.17%,C.Sordelli was 3.45%and C.Tertium was 3.45%.From the detection rate of Clostridium,we can see that infant feces are contaminated by C.Sporogenes.And the contamination may come from DPIF or the environment where babies live such as soil,dust and water.As there were bioactive substances in breast milk,breastfeeding can reduce the contamination of Clostridium lower than formulafeeding.Because lactoferrin,lysozyme and immunoglobulin have the ability to inhibit bacteria growing. |
