Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K.L. Ledeganckstraat 35, 9000 Ghent, Belgium; Laboratoire de Microbiologie et Biologie Moléculaire, Centre National pour la Recherche Scientifique et Technique, Angle av. Allal El Fassi, av. des FAR, Quartier Hay Ryad, BP. 8027 Nations Unies, 10102 Rabat, Morocco.
Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K.L. Ledeganckstraat 35, 9000 Ghent, Belgium.
Int J Food Microbiol. 2021 Mar 2;341:109050. doi: 10.1016/j.ijfoodmicro.2021.109050. Epub 2021 Jan 20.
Dromedary camel milk is generally considered a valuable and marketable commodity but its production suffers from poor hygienic conditions that result in low microbiological quality and the presence of various pathogens. The objective of the present study was to provide a detailed report of the bacterial species level composition of Moroccan raw camel milk samples that can serve as a starting point for the selection of starter cultures to facilitate a change in manufacturing practices to an improved and safer production system. The composition of the bacterial community in four freshly collected raw camel milk samples was analyzed by performing a large-scale isolation campaign combined with 16S rRNA gene amplicon sequencing. A total of 806 isolates were obtained from four raw camel milk samples using ten combinations of growth media and incubation conditions. Subsequent isolate dereplication using MALDI-TOF mass spectrometry and identification of representative isolates through sequence analysis of protein encoding and 16S rRNA genes revealed the presence of established and novel dairy lactic acid bacteria, as well as bacteria that are considered indicators of poor hygienic conditions and psychrotrophic spoilage organisms. The large numbers of Lactococcus and Enterococcus isolates obtained present an interesting resource for starter culture selection.
双峰驼乳通常被认为是一种有价值且有市场的商品,但由于卫生条件差,导致其微生物质量较低,存在多种病原体。本研究的目的是详细报告摩洛哥原料驼乳样品的细菌种类组成,为选择发酵剂提供依据,以促进生产方式的改变,建立更安全的生产体系。通过大规模的分离培养和 16S rRNA 基因扩增测序,对 4 份新鲜采集的原料驼乳样品中的细菌群落组成进行了分析。从 4 份原料驼乳样品中采用 10 种不同的组合的培养基和培养条件共获得了 806 株分离菌。随后通过 MALDI-TOF 质谱进行分离菌的去重复鉴定,并对代表性分离菌的蛋白编码基因和 16S rRNA 基因进行序列分析,鉴定出了已建立的和新的乳制品乳酸菌,以及被认为是卫生条件差和低温腐败指示菌的细菌。大量获得的乳球菌和肠球菌分离株为发酵剂选择提供了有趣的资源。