Determination of metabolites of diosmetin-7-O-glucoside by a newly isolated Escherichia coli from human gut using UPLC-Q-TOF/MS.
Different human intestinal bacteria were isolated and screened for their ability to transform diosmetin-7-O-glucoside. A Gram-negative anaerobic bacterium, strain 4, capable of metabolizing diosmetin-7-O-glucoside was newly isolated. Its 16S rRNA gene sequence displayed 99% similarity with that of Escherichia. Then strain 4 was identified as a species of the genus Escherichia and was named Escherichia sp. 4. Additionally, an ultraperformance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS) technique combined with Metabolynx software method was established to screen the metabolites of diosmetin-7-O-glucoside. Comparing the retention time and MS/MS spectrum, three metabolites were detected and tentatively identified. These metabolites were acquired by four proposed metabolic pathways including dehydroxylation, deglycosylation, methylation, and acetylation. Diosmetin-7-O-glucoside was mainly bioconverted to considerable amounts of diosmetin and minor amounts of acacetin by the majority of the isolated intestinal bacteria such as Escherichia sp. 4. Subsequently, several strains could degrade acacetin to produce methylated and acetylated acacetin. The metabolites and metabolic pathways of diosmetin-7-O-glucoside by human intestinal bacterium Escherichia sp. 4 were first investigated.
Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine , 138 Xianlin Road, Nanjing 210023, People's Republic of China.
Min
M
Zhao
Leyue
L
Du
Jinhua
J
Tao
Dawei
D
Qian
Er-xin
EX
Shang
Shu
S
Jiang
Jianming
J
Guo
Pei
P
Liu
Shu-lan
SL
Su
Jin-ao
JA
Duan
D002853:Chromatography, Liquid; D004926:Escherichia coli / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D005243:Feces / Q000737:chemistry / Q000382:microbiology; D047309:Flavones / Q000378:metabolism*; D005960:Glucosides / Q000378:metabolism*; D006801:Humans; D007422:Intestines / Q000382:microbiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D053719:Tandem Mass Spectrometry
D047309:Flavones; D005960:Glucosides; D012336:RNA, Ribosomal, 16S
16S rRNA; UPLC-Q-TOF/MS; diosmetin-7-O-glucoside; human intestinal bacteria; metabolism