• Archives of Pharmacal Research
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• v.27 no.9
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• pp.968-972
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• 2004

A 1, 2-diglyceride-based multi-step colorimetric assay to measure the pancreatic lipase activ-ity was applied for the determination of the kinetic profiles of the lipase inhibition with a slight modification and the validity verification. With this assay method, our study revealed that platy-codin D, one of major constituents of Platycodi Radix, inhibits the pancreatic lipase activity in a competitive type, with the value of $K_1$ being 0.18${\pm}$0.02 mM. In addition, PO has affected the val-ues of $K_{m}$, app/ and $K_{cat}$/$K_{m}$ in a dose-dependent manner. The results shed a meaningful light on how PO mediates lipid metabolism in the intestinal tracts. On the other hand, since the revised assay is sensitive, rapid, and does not affect the accuracy to the kinetic properties, it is applica-ble not only to evaluation of the kinetic properties of the pancreatic lipase, but also to high-throughput screening of pancreatic lipase activity.

• Archives of Pharmacal Research
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• v.27 no.10
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• pp.1048-1052
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• 2004

A 1, 2-diglyceride-based multi-step colorimetric assay to measure the pancreatic lipase activity was applied for the determination of the kinetic profiles of the lipase inhibition with a slight modification and the validity verification. With this assay method, our study revealed that platycodin D, one of major constituents of Platycodi Radix, inhibits the pancreatic lipase activity in a competitive type, with the value of $K_I$ being 0.18${\pm}$0.02 mM. In addition, PD has affected the values of $K_{m,app}\;and\;K_{cat}/K_m$ in a dose- dependent manner. The results shed a meaningful light on how PD mediates lipid metabolism in the intestinal tracts. On the other hand, since the revised assay is sensitive, rapid, and does not affect the accuracy to the kinetic properties, it is applicable not only to evaluation of the kinetic properties of the pancreatic lipase, but also to highthroughput screening of pancreatic lipase activity.

• Journal of Life Science
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• v.18 no.8
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• pp.1159-1163
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• 2008

The purpose of this study was to establish a high-throughput assay method capable of estimating specific lipase activity at oil-water interface. The method is based on the fact that fluorescence intensity of fluorescein is affected by pH. The pH-dependence might be used to monitor pH change caused by the release of fatty acid through the action of lipase. Assay was performed by incubating a reaction mixture containing oil emulsion, fluorescein and enzyme and by monitoring fluorescence intensity periodically. Fluorescence intensity decreased linearly with a rate proportional to the enzyme amount. Linear relationship was observed between enzyme amount and reaction rate which was calculated from a graph of fluorescence change against time. The assay was possible at different pH conditions in the range of pH 6.0-8.0.

• BMB Reports
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• v.36 no.4
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• pp.417-420
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• 2003

The present work describes a colorimetric microplate assay for lipase activity based on the reaction between 5,5'-dithiobis(2-nitro benzoic acid) (DTNB) and the hydrolysis product of 2,3-dimercapto-1-propanol tributyrate (DMPTB). Reaction mixtures containing DTNB, DMPTB, and lipase were prepared in microplate wells, and the absorbance at 405nm was recorded after incubation at $37^{\circ}C$ for 30 min. A linear relationship was obtained in the range of 0.1-1 U of lipase activity by this method. The reaction conditions were also optimized for the range of 0.01-0.1 U or 1-10 U. When assaying crude tissue extracts, the reaction of DTNB with non-specific reducing agents created a major source of error. However, this error was corrected by the use of blank samples that did not contain DMPTB.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.556-562
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• 2013

We examined the anti-obesity effects of water-soluble polysaccharides (WSP-A) extracted from the seaweed Hijikia fusiforme (Tott in Korean). The extracted alginate-like polysaccharide (verified by FT-IR and HPAEC-PAD analysis) was examined in a lipase inhibition assay and animal experiments. WSP-A inhibited lipase up to 30%, with over 80% of the initial activity retained until the 1 hour reaction in vitro. There was a 30% loss in the rate of weight gain in rats fed a high-fat diet. WSP-A therefore seems to serve as a healthy weight loss agent by inhibiting lipases, thus preventing the absorption of fat in the body.

• Textile Coloration and Finishing
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• v.8 no.4
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• pp.25-30
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• 1996

This study was carried out to examine the effect of lipase on the removal of tripalmitin in the various conditions of washing. The relations between the removal and the hydrolysis of tripalmitin by lipase were discussed. The hydrolysis characteristics of lipase were examined by a colorimetric determination of liberated fatty acids as a new assay of lipase in reverse micelies. The hydrolysis of tripalmitin by lipase was increased with the increase of reaction time and reaction above lipase concentration 150mg/l pH at reaction temperature 4$0^{\circ}C$.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.81-81
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• 2018

The present study was investigated on in vitro anti-obesity effect of 4-hydroxybenzyl alcohol from Cudrania tricuspidata. We isolated various compounds from Cudrania tricuspidata. Among these compounds, anti-obesity effects of 4-hydroxybenzyl alcohol was examined by lipase activity assay, cyclic adenosine monophosphate (cAMP)-specific phosphodiesterase type IV (PDE4) activity assay, and citrate synthase activity assay. 4-hydroxybenzyl alcohol and Cudrania tricuspidata extracts inhibited the enzymatic activities of lipase, PDE4, and citrate synthase. Lipase is known to mediate the hydrolysis of triacylglycerol in adipose tissue and cholesterol esters in other tissue or cells. Also, PDE4 hydrolyses cAMP, a crucial secondary messenger for in metabolic pathways including glucose and lipid metabolism, lipolysis, and thermogenic function. 4-hydroxybenzyl alcohol and Cudrania tricuspidata extracts induced the inhibitory effect against each enzymatic activity on several specific substrates as observed by detection at 405 or 412 nm. These findings might be attributable to the inhibition of adipogenesis, and partial prevention of obesity. In conclusion, these results show that 4-hydroxybenzyl alcohol and Cudrania tricuspidata may be a critical candidate as a natural anti-obesity source.

• Microbiology and Biotechnology Letters
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• v.48 no.4
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• pp.491-505
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• 2020

A newly isolated strain, Proteus vulgaris OR34, from olive mill waste was found to secrete an alkaline extracellular lipase at 11 U·ml-1 when cultivated on an optimized liquid medium. This lipase was purified 94.64-fold with a total yield of 9.11% and its maximal specific activity was shown to be 3232.58 and 1777.92 U·mg-1 when evaluated using the pH-stat technique at 55℃ and pH 9 and Tributyrin TC4 or olive oil as the substrate. The molecular mass of the pure OR34 lipase was estimated to be around 31 kDa, as revealed by SDS-PAGE and its substrate specificity was investigated using a variety of triglycerides. This assay revealed that OR34 lipase preferred short and medium chain fatty acids. In addition, this lipase was stable in the presence of high concentrations of bile salt (NaDC) and calcium ions appear not to be necessary for its activity. This lipase was inhibited by THL (Orlistat) which confirmed its identity as a serine enzyme. In addition, the immobilization of OR34 lipase by adsorption onto calcium carbonate increased its stability at higher temperatures and within a larger pH range. The immobilized lipase exhibited a high tolerance to organic solvents and retained 60% of its activity after 10 months of storage at 4℃. Finally, the OR34 lipase was applied in biodiesel synthesis via oleic acid mediated esterification of methanol when using hexane as solvent. The best conversion yield (67%) was obtained at 12 h and 40℃ using the immobilized enzyme and this enzyme could be reused for six cycles with the same efficiency.

• The Korean Journal of Food And Nutrition
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• v.32 no.1
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• pp.27-32
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• 2019

The objective of this study was to evaluate novel usability as natural anti-obesity supplement of Selaginella tamariscina extract. The total phenol contents and total flavonoid contents were $60.29{\pm}3.11GAE\;mg/g$ and $14.90{\pm}0.34QE\;mg/g$, respectively. To evaluate anti-obesity activity of Selaginella tamariscina extract, pancreatic lipase inhibition activity as well as its inhibition effect of lipid accumulation in adipocytes were conducted by Oil Red O staining and lipolysis assay. The result of pancreatic lipase inhibition activity of S. tamariscina extract showed a wide range between 40 and 73% dose dependently. While the incubation of 3T3-L1 cells with S. tamariscina extract inhibited differentiation of preadipocytes and reduced lipid accumulation, the level of released free glycerol into culturing medium was increased in multiple concentrations. These results showed that S. tamariscina extract inhibit adipogenesis and pancreatic lipase activity. Thus, S. tamariscina extract can be a candidate for regulating lipid accumulation in obesity.

• Food Science and Preservation
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• v.18 no.1
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• pp.53-58
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• 2011

Activity-guided isolation from an ethylacetate-soluble fraction of a 70% (v/v) ethanolic extract from the roots of Taraxacum ohwianum, using a pancreatic lipase inhibition assay, resulted in isolation and identification of five phenolic metabolites of previously known structure; these were 3,5-di-O-caffeoylquinic acid, chicoric acid, caffeic acid, protocatechuic aldehyde, and luteolin. All structures were confirmed by NMR and MS scpectroscopic data. Of these compounds 3,5-di-O-caffeoylquinic acid exhibited the most potent inhibitory activity, with $IC_{50}$ of $65.1{\pm}0.7\;{\mu}M$ against pancreatic lipase.