Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.2.1.23 (
beta-galactosidase
)
14,648
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Rutin and quercitrin are hydrolysed to quercetin, and robinin is hydrolysed to
kaempferol
, by faecal flora from healthy subjects. The enzymes required for these hydrolyses, namely alpha-rhamnosidase and
beta-galactosidase
, were produced by some strains of Bacteroides distasonis; other strains, however, synthesized beta-glucosidase. The last-named enzyme was also elaborated by Bacteroides uniformis and Bacteroides ovatus. All the enzymes were produced constitutively. A cell-free extract of B. distasonis containing beta-glucosidase displayed an enzymic activity of 1 mumol/10 min per 10 mg of protein.
...
PMID:Hydrolysis of dietary flavonoid glycosides by strains of intestinal Bacteroides from humans. 343 94
Cyclooxygenase-2 (COX-2) is abundantly expressed in colon cancer cells. It has been reported that inhibition of COX-2 enzyme activity is shown to prevent colon carcinogenesis. Thus, suppression of COX-2 expression may also be an effective chemopreventive strategy. In the present study, we constructed a
beta-galactosidase
reporter gene system in human colon cancer DLD-1 cells, and measured COX-2 promoter-dependent transcriptional activity in the cells. Interferon gamma suppressed this COX-2 promoter activity, while 12-O-tetradecanoylphorbol-13-acetate and transforming growth factor alpha (TGFalpha) exerted enhancing effects. We then tested the influence of 14 candidate cancer chemopreventive compounds on COX-2 promoter activity. Chemopreventive agents such as quercetin,
kaempferol
, genistein, resveratrol and resorcinol, all having a common resorcin moiety, were found to effectively suppress the COX-2 promoter activity with and without TGFalpha-stimulation in DLD-1 cells. Since all these compounds have a resorcin moiety as a common structure, a resorcin-type structure may play an active role in the inhibition of COX-2 expression in colon cancer cells.
...
PMID:Suppression of cyclooxygenase-2 promoter-dependent transcriptional activity in colon cancer cells by chemopreventive agents with a resorcin-type structure. 1078 18
Two
kaempferol
glycosides were isolated from green tea seed extract (GTSE). After conducting a structure analysis, these two compounds were identified as
kaempferol
-3-O-[2-O-beta-D-galactopyranosyl-6-O-alpha-L-rhamnopyranosyl]-beta-D-glucopyranoside (compound 1) and
kaempferol
-3-O-[2-O-beta-D-xylopyranosyl-6-O-alpha-L-rhanmopyranosyl]-beta-D-glucopyranoside (compound 2). These two compounds were hydrolysed by o-glycolytic enzymes for the production of
kaempferol
. After performing several reactions, we found the optimum enzyme combination, a reaction with
beta-galactosidase
and hesperidinase. Finally, we produced
kaempferol
of above 95% purity. The 5alpha-reductase inhibition activities of GTSE hydrolysate (GTSE-H) containing
kaempferol
were evaluated by the contact cell-based metabolic method using a stable HEK 293 cell line. GTSE-H showed a good inhibition effect on HEK 293 cell lines both type 1 and type 2 on 5alpha-reductase. Especially, GTSE-H inhibited type 2 with
kaempferol
content dependency. The results indicate that the inhibition activity of hydrolysate on 5alpha-reductase type 2 increases in accordance with
kaempferol
content.
...
PMID:Enzymatic hydrolysis of green tea seed extract and its activity on 5alpha-reductase inhibition. 1649 54
Among the flavonols in green tea,
kaempferol
has many biological activities but
kaempferol
of plant origin is too expensive to be used in commercial products. Recently, we confirmed that green tea seed (GTS) contained a reasonable amount of
kaempferol
glycoside. After conducting structure analysis, two
kaempferol
glycosides were identified,
kaempferol
-3-O-[2-O-beta-D-galactopyranosyl-6-O-alpha-L-rhamnopyranosyl]-beta-D-glucopyranoside (compound 1) and
kaempferol
-3-O-[2-O-beta-D-xylopyranosyl-6-O-alpha-L-rhamnopyranosyl]-beta-D-glucopyranoside (compound 2), respectively. Also, a commercially useful method for
kaempferol
preparation was suggested by enzymatic hydrolysis using these two flavonoids. After several enzyme reactions were performed for the complete bioconversion of compounds 1 and 2 to
kaempferol
, we found that the optimum enzyme combination was reaction with
beta-galactosidase
and hesperidinase. Finally, we produced pure
kaempferol
with over 95% purity. We also compared the antioxidant effect of these two GTS flavonoids and its aglycone,
kaempferol
.
Kaempferol
is a more efficient scavenger of 1,1-diphenyl-2-picrylhydrazyl radicals and a better inhibitor of xanthine/xanthine oxidase than the two glycosides.
...
PMID:Enzymatic preparation of kaempferol from green tea seed and its antioxidant activity. 1660 14
Eleven compounds released from germinating seeds of a black-seeded bean (Phaseolus vulgaris L., cv PI165426CS) induce transcription of nod genes in Rhizobium leguminosarum biovar phaseoli. Aglycones from 10 of those compounds were identified by spectroscopic methods (ultraviolet/visible, proton nuclear magnetic resonance, and mass spectroscopy), and their biological activities were demonstrated by induction of
beta-galactosidase
activity in R. leguminosarum strains containing nodA-lacZ or nodC-lacZ fusions controlled by R. leguminosarum biovar phaseoli nodD genes. By making comparisons with authentic standards, the chemical structures for aglycones from the 10 molecules were confirmed as being anthocyanidins (delphinidin, petunidin, and malvidin) and flavonols (myricetin, quercetin, and
kaempferol
). All anthocyanidins and flavonols had 3-O-glycosylation and free hydroxyl groups at the 4', 5, and 7 positions. Hydrolysis experiments showed that the mean concentration required for half-maximum nod gene induction (I(50)) by the 10 glycosides was about half that of the corresponding aglycones. The mean I(50) value for the three anthocyanidins (360 nanomolar) was less (P </= 0.05) than that of the three flavonol aglycones (980 nanomolar). Each seed released approximately 2500 nanomoles of anthocyanidin and 450 nanomoles of flavonol nod gene inducers in conjugated forms during the first 6 hours of imbibition. Based on amounts and activities of the compounds released, anthocyanins contributed approximately 10-fold more total nod-inducing activity than flavonol glycosides. These anthocyanidins from bean seeds represent the first nod-inducing compounds identified from that group of flavonoids.
...
PMID:Anthocyanidins and Flavonols, Major nod Gene Inducers from Seeds of a Black-Seeded Common Bean (Phaseolus vulgaris L.). 1666 62
Two flavonol triglycosides, camelliaside A (CamA) and camelliaside B (CamB), of tea seed extract (TSE) were subjected to enzymatic hydrolysis. Among five kinds of glycosidases investigated,
beta-galactosidase
(Gal) induced selective hydrolysis of CamA. On the other hand, pectinase (Pec) and cellulase (Cel) induced hydrolysis of CamB. For Gal and Pec, only
kaempferol
diglycoside (nicotiflorin, NF) was produced; on the other hand, significant amounts of
kaempferol
monoglycoside (astragalin, AS) and
kaempferol
(KR) were also detected for Cel. The combination of the use of Gal and Pec in the enzymatic hydrolysis of TSE afforded NF with high specificity. Crude NF with 22% purity was recovered from the enzymatic reaction mixture by extraction with organic solvent, and pure NF with >95% purity was obtained by crystallized in water. The chemical structure of NF was confirmed by (1)H and (13)C NMR analyses.
...
PMID:Isolation and characterization of nicotiflorin obtained by enzymatic hydrolysis of two precursors in tea seed extract. 2022 59