• 약학회지
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• 제38권1호
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• pp.78-85
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• 1994

From phase solubility studies bile acids and bile salts were found to form stable inclusion complexes with ${\beta}-cyclodextrin$ in aqueous solution. Stability constant of bile acids were larger than that of bile salts. Phase solubility diagrams of most bile acids showed Higuchi's $A_I$ type but lithocholic acid showed $B_S$ type. Not only the solubility of bile acids but also that of ${\beta}-cyclodextrin$ increased, especially in cases of cholic acid and ursodeoxycholic acid. Solubility increase of bile acids from their ${\beta}-cyclodextrin$ inclusion complex followed the order : cholic acid>ursodeoxycholic acid>chenodeoxycholic acid>deoxycholic acid>lithocholic acid. It seems that solubility of inclusion complexes was directly related with the hydrophilicity of bile acids.

• 한국미생물·생명공학회지
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• 제50권1호
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• pp.102-109
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• 2022

Bile acids are essential molecules produced by vertebrates that are involved in several physiological roles, including the uptake of nutrients. Bacterial isolates capable of producing bile acids de novo have been identified and characterized. Such isolates may provide access to novel biochemical pathways suitable for the design of microbial cell factories. Here, we further characterized the ability of Maribacter dokdonensis, Dokdonia donghaensis, and Myroides pelagicus to produce bile acids. Contrary to previous reports, we did not observe de novo production of bile acids by these isolates. Instead, we found that these isolates deconjugated the amino acid moiety of bile acids present in the growth medium used in previous reports. Through genomic analysis, we identified putative bile salt hydrolases, which could be responsible for the different bile acid modifications observed. Our results challenge the hypothesis of de novo microbial bile acid production, while further demonstrating the diverse capacity of bacteria to modify bile acids.

• Journal of Nutrition and Health
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• 제29권1호
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• pp.41-49
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• 1996

Bacterial transformation of bile acids is possibly involved in colorectal carcinogenesis. n several epidemiological studies, the fecal bile acid dietary fiber are related to the indicence of colonic cancer. This study investigated the influence of age, dietary fiber intake on fecal bile acid profiles in healthy subject. The dietary fiber were assessed by mean of 24 hour dietary recall method, the subjects consist of 238 members aged 20 to 64 years old and feces are collected from the subjects. Fecal bile acids and neutral sterols were analyzed by gas chromatography. Mean dily crude fiber intake level was 7.7$\pm$1.4g(dietary fiber : 16.7$\pm$3.5g), dietary fiber intake range being 6.5-36.8g. The dietary fiber intake in elederly subject was significantly lower than in the other younger groups. Dietary fiber intakes was negatively correlated with the total bil acid concentation in feces. Probably, a decrease in dietary fiber intake results in higher fecal bile acid concentrations. The secondary bile acid concentration is related to the colon cancer, deoxycholic acid and lithocholic acid were significantly higher in elderly subjects. Concentration of fecal total bile acid, deoxycholic acid, coprostanol, coprostanone were higher in low dietary fiber intake group. These results suggest that the risk factor for colon cancer might be reduced, when dietary fibers are consummed more.

• 한국임상약학회지
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• 제21권2호
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• pp.49-56
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• 2011

The family of bile acids belongs to a group of molecular species of acidic steroids with very peculiar biological characteristics. They are synthesized by the liver from cholesterol through several complementary pathways and secreted into small intestine for the participation in the digestion and absorption of fat. The bile acids are mostly confined to the territories of the so-called enterohepatic circulation, which includes the liver, the biliary tree, the intestine and the portal blood with which bile acids are returned to the liver. In patients with bile acid malabsorption, the amount of primary bile acids in the colon is increased compared to healthy controls. Although the increase in the secondary bile acids including deoxycholic acid, is reported to have the potency to affect tumorigenesis in gastrointestinal tracts, there is no firm evidence that clinically relevant concentrations of the bile acids induce cancer. The list of their physiological roles, as well as that of the pathological processes is long and still not complete. There is no doubt that many new concepts, pharmaceutical tools and pharmacological uses of bile acids and their derivatives will emerge in the near future.

• Laboraroty Animal Research
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• 제34권4호
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• pp.140-146
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• 2018

Though bile acids have been well known as digestive juice, recent studies have demonstrated that bile acids bind to their endogenous receptors, including Farnesoid X receptor (FXR) and G protein-coupled bile acid receptor 1 (GPBAR1; TGR5) and serve as hormone to control various biological processes, including cholesterol/bile acid metabolism, glucose/lipid metabolism, immune responses, and energy metabolism. Deficiency of those bile acid receptors has been reported to induce diverse metabolic syndromes such as obesity, hyperlipidemia, hyperglycemia, and insulin resistance. As consistent, numerous studies have reported alteration of bile acid signaling pathways in type II diabetes patients. Interestingly, bile acids have shown to activate TGR5 in intestinal L cells and enhance secretion of glucagon-like peptide 1 (GLP-1) to potentiate insulin secretion in response to glucose. Moreover, FXR has been shown to crosstalk with TGR5 to control GLP-1 secretion. Altogether, bile acid receptors, FXR and TGR5 are potent therapeutic targets for the treatment of metabolic diseases, including type II diabetes.

• The Korean Journal of Physiology and Pharmacology
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• 제4권4호
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• pp.333-338
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• 2000

We have examined whether bile acids can affect the electrical and mechanical activities of circular smooth muscle of canine colon and ileum, using isometric tension measurement or patch clamp technique. It was found that a dilution of canine bile $(0.03{\sim}2%\;by\;volume)$ enhanced or inhibited the amplitude of spontaneous contractions. An individual component of bile, deoxycholic acid (DCA) enhanced the frequency and amplitude of the spontaneous contractile activity at $10^{-6}\;M,$ while DCA at $10^{-4}\;M$ inhibited the contraction. Similarly, the response to cholic acid was excitatory at $10^{-5}\;M$ and inhibitory at $3{\times}10^{-4}\;M.$ Taurocholic acid at $10^{-4}\;M$ enhanced the amplitude of muscle contraction. Electrically, canine bile at 1% reversibly depolarized the colonic myocytes under current clamp mode. Bile acids also elicited non-selective cation currents under voltage clamp studies, where $K^+$ currents were blocked and the $Cl^-$ gradient was adjusted so that $E_{Cl}^-$ was equal to -70 mV, a holding potential. The non-selective cation current might explain the depolarization caused by bile acids in intact muscles. Furthermore, the bile acid regulation of electrical and mechanical activities of intestinal smooth muscle may explain some of the pathophysiological conditions accompanying defects in bile reabsorption.

• 한국수산과학회지
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• 제30권1호
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• pp.31-38
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• 1997

추출조건에 따른 다시마 alginate의 성질을 조사하기 위하여 추출용매인 $Na_{2}CO_{3}$의 농도를 1, 3, 및 $5\%$로 각각 조절하고 추출시간을 각각 1, 3, 5 및 10시간으로 하였을때 각 추출조건에서 추출된 alginate의 bile acids 결합능과 물리화학적 특성을 조사한 결과는 다음과 같다. 건조다시마를 미세하게 마쇄할수록, $Na_{2}CO_{3}$ 농도와 추출시간이 증가할수록 alginate 추출량은 증가하였다. alginate의 bile acids와의 결합능은 저 농도의 $Na_{2}CO_{3}$ 용액으로 단시간에 추출한 것일수록 높게 나타났다. alginate에 의한 bile acids 결합능은 cholic acid에서 가장 높게 나타났고, taurocholic acid, glycocholic acid, deoxycholic acid 순으로 조사되었다. 다시마로 부터 alginate를 추출하고 남은 잔사(RAEA)의 bile acids와의 결합능은 alginate의 경우와 같이 추출 용액의 농도가 높을수록 추출시간이 길어질수록 감소하는 경향을 보였다. Bile acids와의 결합능은 cholic acid, taurocholic acid의 경우 alginate보다 다소 낮은 값을 나타냈고, glycocholic acid의 경우 alginate와 비슷한 값을 보였으나 deoxycholic acid와의 결합능은 추출된 alginate보다도 오히려 높은 값을 보였다. 추출된 alginate의 점도와 중합도는 추출용액의 농도가 증가하고 추출시간이 길어짐에 따라 감소하였으며 이에 비례하여 bile acid와의 결합능도 감소하였다.

• 대한약리학회지
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• 제18권1호
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• pp.43-54
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• 1982

Bile formation is a complex process comprised of three separate physiologic mechanism operating at two anatomical sites. At present time, it was known that at least two processes are responsible for total canalicular secretion at the bile canaliculus. One of the processes is bile salt-dependent secretion (BSDS) hypothesis that the active transport of bile salts from plasma to bile provided a primary stimulus for bile formation: the osmotic effect of actively transported bile acid was responsible for the movement of water and ions into bile. The other process is bile salt-independent secretion (ESIS), which is unrelated to bile salt secretion at the canaliculus and which may involve the active transport of sodium. The third process for bile formation involves the biliary ductal epithelium. Secretin-stimulated bile characteristically contained bicarbonate in high concentration. Therefor, it was suggested that secretin stimulated water and bicarbonate secretion from the biliary ductules. One the other hand, it was found that a large amounts of cAMP was present in canine bile but no apparent relationship between bile salt secretion and cAMP content in dog bile. However, bile flow studies in human have demonstrated that secretin and glucagon increase bile cAMP secretion as does secretin in baboons. Secretin increases baboon bile duct mucosal cAMP levels in addition to bile CAMP levels suggesting that in that species secretin-stimulated bile flow may be cAMP mediated. It has been postulated that glucagon and theophylline which increase the bile salt-independent secretion in dogs might act through an increased in liver cAMP content. In a few studies, the possible role of cAMP on bile formation has teen tested by administration of an exogenous derivative of cAMP, dibutyryl cAMP. In the rat, DB cAMP did not modify bile flow, but injection of DB cAMP in the dog promoted an increase in the bile salt-independent secretion. Because of these contradictory results, this study was carried out to examine the relationship between cyclic nucleotides and bile flow due to various bile salts as well as secretin or theophylline. Experiments were performed in rabbits with anesthesia produced by the injection of seconal(30 mg/kg). Rabbits had the cystic duct ligated and the proximal end of the divided common duct cannulated with an appropriately sized polyethylene catheter. A similar catheter was placed into the inferior vena cava for administration of drugs. Bile was collected for determination of cyclic nucleotides and total cholate in 15 min. intervals for a few hours. The results are summerized as followings. 1) Administrations of taurocholic acid or chenodeoxycholic acid increased significantly the concentrations of cAMP and cGMP in bile of rabbits. 2) Concentration of cAMP in bile during the continuous infusion of ursodeoxycholic acid, was remarkedly increased in accordance with the increase of bile flow, while on the contrary concentration of cGMP in bile was decreased significantly. 3) Dehydrocholic acid and deoxycholic acid significantly increased bile flow, total cholate output and cyclic nucleotides in bile. 4) Only cAMP concentration in bile was significantly increased from control value by secretin, while theophylline increased cAMP as well as cGMP in rabbit bile. 5) In addition, the administration of secretin to taurocholic acid-stimulated bile flow increased cAMP while theophylline produced the increases of cAMP and cGMP in bile. 6) The administration of insulin to taurocholic acid-stimulated bile flow decreased cAMP concentration, while on the contrary cGMP was remarkedly increased in rabbit bile.

• 한국식품영양과학회지
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• 제34권3호
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• pp.351-355
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• 2005

식이섬유의 기능을 가지는 저항전분(HM: HI-MAIZE)과 저항전분에 차전자피를 포함한 탄수화물로 구성된 D-factor를 10% 가하여 제조한 식이섬유(HM-D: HI-MAIZE DIET)의 특성을 비교하기 위하여 glucose 및 bile acid 흡수저해효과 및 장내 세균에 의한 혐기적 발효산물인 단쇄지방산의 함량을 각각 비교하였다 반투막을 이용하여 glucose흡수저해효과를 측정한 결과, HM에 비하여 HM-D의 경우 glucose 저해효과가 다소 우세한 것으로 나타났으며, 투석 막을 통한 glucose 투과는 4시간 경과 시 HM은 77%와 HM-D는 68%를 보였으며, 24시간까지 연장시 glucose는 거의 전부 투과되었다. 투석 막을 이용한 bile acid 흡수저해효과는 HM시료에 비하여 D-factor가 첨가된 저항전분의 경우 bile acid 흡수저해효과가 우수함을 알 수 있었으며, 투석막을 통한 bile acid 투과는 서서히 일어났으며 24시간 경과 시 HM과 HM-D의 경우 65%와 62.3%의 bile acid 투과가 이루어 졌다. 장내 세균에 의한 단쇄지방산 생성은 HM의 경우 217.8mM, HM-D는 264.0mM로 HM-D의 경우 더 많은 양의 단쇄지방산의 생성량을 보였으며, butyric acid 생성 양은 HM-D가 32.7mM로 26.9mM생성량을 보인 HM에 비하여 높았다. 따라서 D-factor첨가에 의해 glucose와 bile acid의 흡수저해 효과가 증가하였을 뿐만 아니라 단쇄지방산의 함량과 butyric acid함량 증가를 보임에 따라 D-factor첨가에 의해 저항전분이 지니는 식이섬유의 기능이 강화되었다.

• 한국미생물·생명공학회지
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• 제23권5호
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• pp.513-518
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• 1995

To evaluate bile salt-tolerance of lactic acid bacteria (LAB, Lactobacillus acidophilus ATCC 4356, Lactobacillus casei IFO 3533, Streptococcus thermnophilus KCTC 2185, Lactobacillus lactis ATCC 4797, and Lactobacillus bulgaricus ATCC 11842), We investigated the survivals, acid production and $\beta $-galactosidase activity of LAB under anaerobic broth system. Cellular permeability of LAB and their cellular retention of $\beta $-galactosidase were also examined in the same system. Although the growth of LAB was slightly suppressed by 0.3% bile salt, they showed normal growth curve. Streptococcus thermophilus KCTC 2185 was significantly more resistant to bile salt than the others. The $\beta $-galactosidase activity from Streptococcus thermophilus KCTC 2185 and Lactobacillus bulgaricus ATCC 11842 and their cellular retention of $\beta $-galactosidase decreased by 0.3% bile salt. The cellular permeability of LAB in the presence of bile salt increased significantly.