TY - JOUR
T1 - Metagenomic analysis of bacterial community composition in Dhanaan
T2 - Ethiopian traditional fermented camel milk
AU - Berhe, Tesfemariam
AU - Ipsen, Richard
AU - Seifu, Eyassu
AU - Kurtu, Mohamed Y.
AU - Fugl, Angelina June Brandt
AU - Hansen, Egon Bech
PY - 2019/5/16
Y1 - 2019/5/16
N2 - This study was conducted to evaluate the safety and bacterial profile of Dhanaan (Ethiopian traditional fermented camel milk). The composition of the microbial community in Dhanaan samples was analysed by a metagenomic approach of 16S rRNA gene amplicon sequencing. Metagenomic profiling identified 87 different bacterial microorganisms (OTUs) in six samples analysed. Although the Dhanaan samples contained various lactic acid bacteria (LAB), they also all contained undesirable microorganisms in large proportions. The following LAB genera were identified: Streptococcus, Lactococcus and Weissella. One Streptococcus species represented by OTU-1 (operational taxonomic unit) was found in all Dhanaan samples and the dominating species in four out of six samples. This common isolate was found to be closely related to S. lutetiensis and S. infantarius. Undesirable microorganisms from genera such as Escherichia, Klebsiella, Enterobacter, Acinetobacter and Clostridium were, however, also frequent, or even dominant in Dhanaan samples. Thus, this calls for a change in the Dahnaan manufacturing practice to an improved and safer production system. Starter cultures suitable for Dhanaan production might be developed from the Streptococcus, Weissella and Lactococcus microorganisms identified in this study. However, further safety evaluation and technological characterization need to be conducted on strains defined by OTU-1, OTU-2, OTU-3, OTU-8 and OTU-35 before they can be used as food grade starter cultures.
AB - This study was conducted to evaluate the safety and bacterial profile of Dhanaan (Ethiopian traditional fermented camel milk). The composition of the microbial community in Dhanaan samples was analysed by a metagenomic approach of 16S rRNA gene amplicon sequencing. Metagenomic profiling identified 87 different bacterial microorganisms (OTUs) in six samples analysed. Although the Dhanaan samples contained various lactic acid bacteria (LAB), they also all contained undesirable microorganisms in large proportions. The following LAB genera were identified: Streptococcus, Lactococcus and Weissella. One Streptococcus species represented by OTU-1 (operational taxonomic unit) was found in all Dhanaan samples and the dominating species in four out of six samples. This common isolate was found to be closely related to S. lutetiensis and S. infantarius. Undesirable microorganisms from genera such as Escherichia, Klebsiella, Enterobacter, Acinetobacter and Clostridium were, however, also frequent, or even dominant in Dhanaan samples. Thus, this calls for a change in the Dahnaan manufacturing practice to an improved and safer production system. Starter cultures suitable for Dhanaan production might be developed from the Streptococcus, Weissella and Lactococcus microorganisms identified in this study. However, further safety evaluation and technological characterization need to be conducted on strains defined by OTU-1, OTU-2, OTU-3, OTU-8 and OTU-35 before they can be used as food grade starter cultures.
KW - Dhanaan
KW - fermented camel milk
KW - lactic acid bacteria
KW - metagenomic analysis
KW - OTU
U2 - 10.1093/femsle/fnz128
DO - 10.1093/femsle/fnz128
M3 - Journal article
C2 - 31183493
AN - SCOPUS:85068808798
SN - 0378-1097
VL - 366
JO - F E M S Microbiology Letters
JF - F E M S Microbiology Letters
IS - 11
M1 - fnz128
ER -