Porcine Pancreatic Lipase Activity Research Articles

Chemical Analysis of the Antihyperglycemic, and Pancreatic α-Amylase, Lipase, and Intestinal α-Glucosidase Inhibitory Activities of Cannabis sativa L. Seed Extracts.

Cannabis is considered (Cannabis sativa L.) a sacred herb in many countries and is vastly employed in traditional medicine to remedy numerous diseases, such as diabetes. This research investigates the chemical composition of the aqueous extracts from Cannabis sativa L. seeds. Furthermore, the impact of these extracts on pancreatic α-amylase and lipase, and intestinal α-glucosidase enzymes is evaluated, as well as their antihyperglycemic effect. Analysis of the chemical composition of the aqueous extract was conducted using high-performance liquid chromatography with a photodiode array detector (HPLC-DAD). In contrast, the ethanol, hexanic, dichloromethane, and aqueous extract compositions have been established. Additionally, the inhibitory effects of ethanolic, dichloromethane, and aqueous extracts on pancreatic α-amylase and lipase, and intestinal α-glucosidase activities were evaluated in vitro and in vivo. The results of HPLC analysis indicate that the most abundant phenolic compound in the aqueous cannabis seed extract is 3-hydroxycinnamic acid, followed by 4-hydroxybenzoic acid and rutin acid. Moreover, administration of ethanolic and aqueous extracts at a dose of 150 mg/Kg significantly suppressed postprandial hyperglycemia compared to the control group; the ethanolic, dichloromethane, and aqueous extracts significantly inhibit pancreatic α-amylase and lipase, and intestinal α-glucosidase in vitro. The pancreatic α-amylase test exhibited an inhibition with IC50 values of 16.36 ± 1.24 µg/mL, 19.33 ± 1.40 µg/mL, 23.53 ± 1.70 µg/mL, and 17.06 ± 9.91 µg/mL for EAq, EDm, EET, and EHx, respectively. EET has the highest inhibitory capacity for intestinal α-glucosidase activity, with an IC50 of 32.23 ± 3.26 µg/mL. The extracts inhibit porcine pancreatic lipase activity, demonstrating their potential as lipase inhibitors. Specifically, at a concentration of 1 mg/mL, the highest inhibition rate (77%) was observed for EDm. To confirm these results, the inhibitory effect of these extracts on enzymes was tested in vivo. The oral intake of aqueous extract markedly reduced starch- and sucrose-induced hyperglycemia in healthy rats. Administration of the ethanolic extract at a specific dose of 150 mg/kg significantly reduced postprandial glycemia compared with the control group. It is, therefore, undeniable that cannabis extracts represent a promising option as a potentially effective treatment for type 2 diabetes.

Screening of Phytochemical and Quantitative Lipase Inhibition of Honey and Cinnamon Paste: A Synergistic Effect

Objective: Obesity is one among the metabolic syndromes caused due to the disproportion in intake and disbursement of energy, it takes the reasons for many non-communicable diseases or chronic disorders like diabetics, heart diseases etc. An imbalanced diet with a composition of high fat foods are the common causative agents for obesity. There are many synthetic therapeutic methods to prevent and reduce obesity which always ends with side effects. The study involves in estimating the anti-obesity properties of honey and cinnamon individually and also their synergistic effect in inhibiting the pancreatic lipase. Methods: Ethanol extract was prepared for honey, cinnamon and their combinations, the qualitative phytochemical screening were done with their standard procedures. Porcine Pancreatic lipase activity was done for the samples at different concentrations from 10 to 60µg/ml. Results: The present study reveals the presence of all tested phytochemicals in the honey-cinnamon paste. With the increase in the concentration of extracts the higher inhibition of the lipase enzyme was observed. Percentage of inhibition ranged from honey 8.48±.041 to 41.49±0.14%, cinnamon 14.48±0.45 to 60.74±0.19% and honey-cinnamon pastes 23.48±0.20 to 87.37±0.20% respectively. Conclusion: The lipase inhibition effect reveals that the honey-cinnamon paste has a synergistic effect against lipase which could positively inhibits and reverts obesity which in turn eventually protects from obesity related non-contagious diseases.

Anti-pancreatic lipase and anti-adipogenic effects of 5,7,3′,4′,5′-pentamethoxy and 6,2′,4′-trimethoxy flavone - An in vitro study

In this study, the anti-obesity effects of 5,7,3′,4′,5′-pentamethoxyflavone (PMF) and 6,2′,4′-trimethoxyflavone (TMF) were evaluated through two distinct mechanisms of action: inhibition of crude porcine pancreatic lipase (PL), and inhibition of adipogenesis in 3T3-L1 pre-adipocytes. Both flavones show dose dependent, competitive inhibition of PL activity. Molecular docking studies revealed binding of the flavones to the active site of PL. In 3T3-L1 adipocytes, both flavones reduced the accumulation of lipids and triglycerides. PMF and TMF also lowered the expression of adipogenic and lipogenic genes. They both reduced the expression of peroxisome proliferator-activated receptor-gamma (PPAR-γ), CCAAT/enhancer-binding protein α and β (C/EBP α and β), sterol regulatory element-binding protein 1 (SREBF 1), fatty acid synthase (FASN), adipocyte binding protein 2 (aP2), and leptin gene. In addition, these flavones enhanced adiponectin mRNA expression, increased lipolysis and enhanced the expression of lipolytic genes: adipose triglycerides lipase (ATGL), hormone sensitive lipase (HSL) and monoglycerides lipase (MAGL) in mature 3T3-L1 adipocytes. Overall, PMF was seen to be a more potent inhibitor of both PL activity and adipogenesis versus TMF. These results suggest that PMF and TMF possess anti-obesity activities and can be further evaluated for their anti-obesity effects.

Immobilization for Lipase: Enhanced Activity and Stability by Flexible Combination and Solid Support

In this study, an enhanced activity and stability method for immobilizing porcine pancreatic lipase (PPL) was developed based on ZIF-8 encapsulated supramolecular-modified gold nanoparticle complexes (pSC4-AuNPs@ZIF-8). Supramolecular calix[4]arene (pSC4) can recognize the amino group of PPL through non-covalent force, and this flexible binding method protected the structure of PPL during the immobilization process. Due to the hydrophilic of pSC4-AuNPs and hydrophobic of ZIF-8, PPL can maintain a "lid open" conformation, which can enhance the stability of PPL structure and reduce PPL activity loss. ZIF-8 was used to immobilize PPL to avoid the difficult recovery of free PPL. Compared with the native form of PPL, it exhibited 70.6% maintained activity with terrific pH and temperature stability, and had good performance in thermal stability, time stability, and reusability. In addition, three immobilized PPL methods were designed to further clarify the influence of synthetic methods and additives on the activity and stability of PPL. Importantly, the loading rate of pSC4-AuNPs@ZIF-8@PPL was up to 51.2% among these immobilized PPL systems. Therefore, pSC4-AuNPs@ZIF-8 may serve as a versatile and promising immobilization system for enzymes.

Anti-obesity activity of polyherbal formulation Divya-Medohar-Vati by inhibition of pancreatic lipase activity and triglyceride translocation through enterocytes

BackgroundObesity is a modern-day epidemic affecting human lifestyle worldwide and originates from high fat-content food consumption. Traditional Ayurveda-based polyherbal medicine ‘Divya-Medohar-Vati’ (DMV) has been recommended as an anti-obesity formulation. MethodsIn the present study, we explored the anti-obesity activity of DMV using biochemical assay, simulated gastrointestinal tract (GIT) digestion model, and Caco-2-derived enterocyte model. We further correlated the observed biological activity of DMV with its phytochemical profile determined using the high-performance-liquid-chromatography method. ResultsPhytochemicals such as Gallic acid, Ellagic acid, Chebulic acid, Picroside I, and Arjungenin were identified in DMV. DMV and ‘Orlistat’ (positive control) showed half-maximal inhibitory concentrations (IC50) of 647.88 and 21.80 µg/ ml, respectively against porcine pancreatic lipase activity. Addition of DMV and Orlistat to full cream during simulated GIT digestion reduced the hydrolysis of triglyceride into long-chain Palmitic acids and glycerol molecules in obtained digestae. At the same time, both DMV and Orlistat stimulated the release of medium-chained Capric acids in full cream digestae. Treatment of enterocytes with DMV-induced a loss of cell viability (IC50 at 308.5 μg/ml). Translocation of re-esterified triglycerides by enterocytes grown on transwell plate following treatment with full cream digestae was inhibited after the addition of DMV and Orlistat. ConclusionsTaken together, DMV showed good inhibition for pancreatic lipase activity, and hydrolysis of triglycerides modulating the release of free glycerol and dietary fatty acid (Capric acid and Palmitic acid) contents. DMV also reduces the translocation of triglycerides through the basal region of enterocytes. Hence, Divya-Medohar-Vati was found to be an effective anti-obesity polyherbal formulation.

Development and characterization of enzymatic biosensor based on lipase from porcine pancreas for propylparaben detection

Purpose The purpose of this paper is to study the immobilization of porcine pancreatic lipase (PPL), in an organic matrix by a covalent cross-linking method to sense propylparaben (PP) present in aqueous solution. Design/methodology/approach PPL immobilization was performed by the covalent cross-linking method, using bovine serum albumin (BSA) in the presence of saturated glutaraldehyde vapor (GA). The preparation of the enzymatic membrane involves the incorporation of porcine pancreatic lipase (PPL), bovine serum albumin (BSA) and glycerol into a phosphate buffer solution (PBS). Characterization of this sensor was performed by impedance spectroscopy (EIS) and scanning electron microscope (SEM). The effect of experimental conditions such as PPL activity, potential, scan rate, PP concentration, pH and presence of interfering elements were studied by cyclic voltammetry. Findings Under the optimal experimental conditions, a number of significant factors were optimized. The method exhibited good linearity in the range of 10–14 to 10–9 mol/L with a good correlation coefficient of 0.957, detection limit (LOD) of 3.66 × 10–15 mol/L and high sensitivity of 1.086 mA mol−1L. The authors also obtained a very good coverage rate of the surface equal to 91.44%, and hydrolytic activity of lipase is evaluated to 26.64 mmol min−1. The stability and the interference were also evaluated. The equivalent circuit used to explain the electrochemical behavior of modified electrode is a Randle circuit. Practical implications The main application of biosensors is the detection of biomolecules that are either indicators of a disease. For example, electrochemical biosensing techniques can be used as clinical tools to detect breast tumors, because these compounds (PP) were found in breast tumors. Originality/value The result registered in this paper indicates that the developed sensor is an efficient, fast, simple and inexpensive analytical tool that can be used for the analysis of water containing PP.

In vitro Inhibition of Pancreatic Lipase by Polyphenols: A Kinetic, Fluorescence Spectroscopy and Molecular Docking Study.

The inhibitory activity and binding characteristics of caffeic acid, p-coumaric acid, quercetin and capsaicin, four phenolic compounds found in hot pepper, against porcine pancreatic lipase activity were studied and compared to hot pepper extract. Quercetin was the strongest inhibitor (IC50=(6.1±2.4) µM), followed by p-coumaric acid ((170.2±20.6) µM) and caffeic acid ((401.5±32.1) µM), while capsaicin and a hot pepper extract had very low inhibitory activity. All polyphenolic compounds showed a mixed-type inhibition. Fluorescence spectroscopy studies showed that polyphenolic compounds had the ability to quench the intrinsic fluorescence of pancreatic lipase by a static mechanism. The sequence of Stern-Volmer constant was quercetin, followed by caffeic and p-coumaric acids. Molecular docking studies showed that caffeic acid, quercetin and p-coumaric acid bound near the active site, while capsaicin bound far away from the active site. Hydrogen bonds and π-stacking hydrophobic interactions are the main pancreatic lipase-polyphenolic compound interactions observed.

Hypolipidemic mechanism of gypenosides via inhibition of pancreatic lipase and reduction in cholesterol micellar solubility

Effect of gypenosides on porcine pancreatic lipase (PL) activity was determined in vitro. Gypenosides inhibited the PL activity in a dose-dependent manner at the concentrations of 0–1.0 mg/ml. The Lineweaver–Burk plots for gypenosides indicated that the inhibition on PL by gypenosides was noncompetitive. The conformation of PL was investigated by means of circular dichroism and fluorescence. The result revealed the decrease in α-helix contents, increase in β-sheet and the decrease in fluorescence intensity after gypenosides treatment. The incorporation of cholesterol into micelles was inhibited by gypenosides. A complex was observed by transmission electron microscopy, indicating interaction between cholesterol and gypenosides which led to the decrease in cholesterol micelle solubility. The result revealed the fact that gypenosides played a role in inhibiting PL activity and reducing intestinal cholesterol absorption via inhibition of micelle formation.

Caffeoylquinic acids competitively inhibit pancreatic lipase through binding to the catalytic triad

Caffeoylquinic acid and its isomers inhibited porcine Pancreatic Lipase (PL) activity according to a competitive mode where binding and interaction with the catalytic triad of Ser153, His264 and Asp177 simultaneously occurred. The IC50 values under which 3-caffeoylquinic acid (CQA) and its isomers 4-, 5-CQA, 3,4-, 3,5- and 4,5-diCQA inhibited half of the porcine PL activity were 1.10, 1.23, 1.24, 0.252, 0.591 and 0.502mM, respectively. The binding affinities in the range from −8.4 to −9.5kCal/mol were well predicted from docking, which showed a high linear correlation coefficient of 0.893 and Spearman correlation of 1.0 with log(IC50) values. Caffeoylquinic acid and its isomers were stabilized by hydrogen bond and hydrophobic interaction in the binding pocket. This finding provided molecular mechanism of coffee and other natural food or drink containing caffeoylquinic acid and its isomers against lipase activity.

Assessment of In-Vitro inhibitory effect of khaya tea infusion on porcine pancreatic lipase activity

The inhibition of digestive lipases is a widely studied mechanism for the determination of the potential efficacy of natural products as anti-obesity agents. In this regard, the use of natural products might be an excellent alternative strategy for the development of safe and effective anti-obesity drugs that lack the unpleasant side effects of existing chemical drugs. The aim of this study was to assess the potential effect of Khaya tea in the treatment of obesity through the evaluation of its in vitro inhibitory effects on porcine pancreatic lipase activity. Extract was obtained by infusion of powder in water 4g/150 ml at 95°C for 10 min and was subjected to chemical analysis and kinetics studies. The in vitro inhibitory effect of Khaya tea on lipase activity was studied by assessing porcine pancreatic lipase activities at varying concentrations of khaya tea extract (0, 1, 2, 3, 4, 5 mg/ml). Results showed that Khaya tea induced a competitive inhibition (85±2%) of the porcine pancreatic lipase activity in the hydrolysis of substrate emulsified with gum arabic : I.C (inhibition Concentration)50 = 0.96 ± 0.03 mg of Khaya tea /ml. These in vitro inhibition results suggest that Khaya tea could be a potential therapeutic alternative in the treatment of obesity caused by fat-rich diets.

Seed meals as source of fractions with different effects on pancreatic lipase activity

The effect of different fractions (lipids, solids soluble in aqueous ethanol (ES), soluble protein (SP), and the residue after the extractions) of yellow lupin (Lupinus luteus), linseed (Linum usitatissimum), and soybean (Glycine max) meals on in vitro porcine pancreatic lipase (PPL) activity was determined. PPL activity against emulsions prepared with the different SPs unprocessed or denaturated by heat, digested with pepsin and homogenized at high pressure was also evaluated. In general, the lipids, ES, and the residue fractions increased PPL activity (8.4–80.0%) whereas it was reduced by the SPs of lupin (25.3%) and linseed (30.8%) at a low concentration. Residual activity after incubating the enzyme with the SPs was found between 13 and 46% depending on the source and the incubating period. The rate at which PPL hydrolyzed emulsions in which lipid droplets were covered first by gum Arabic and then with the protein was influenced by the treatment of SP; less free fatty acids were released from emulsions containing the denaturated and digested SPs. PPL activity against emulsions that contained the homogenized SPs was higher (108–174%) than the activity against emulsions that contained the untreated SP.Practical applications: Lupin, linseed, and soybean meals contain various fractions that increase the activity of PPL; however the soluble proteins of lupin and linseed exert the opposite effect at low concentrations with the subsequent reduction of lipolysis products. Besides emulsions prepared with denaturated or protease digested seed proteins are hydrolyzed at low rates by PPL. This property of the seed proteins could find use in the developing of foods for weight control for instance plant‐based milks and creams. On the other hand, high pressure homogenization could be used as a treatment for decrease the negative effect of seed proteins on the activity of PPL.

Anti- and Pro-Lipase Activity of Selected Medicinal, Herbal and Aquatic Plants, and Structure Elucidation of an Anti-Lipase Compound

Plants that help in slowing down the digestion of triacylglycerols (TAGs) in the pancreas and small intestine of humans play an important role in the reduction of obesity. On the other hand, there may be plants or plant parts that stimulate intestinal lipolytic activity, thus contributing to greater TAG assimilation. The aim of this study was to evaluate the aqueous methanolic extracts of ninety eight (98) medicinal, herbal and aquatic plant materials from Malaysia for their effect on porcine pancreatic lipase (PPL) activity and to identify the structure of an anti-lipase compound from one of the sources. The degree of inhibition was also quantified as relative to orlistat activity against PPL (orlistat equivalents). Results revealed that while 19.4% of the extracts were found to have anti-lipase activity ≥80%, 12% were actually found to promote PPL activity. Twenty two percent (22.4%) exhibited moderate inhibition (41%–80%) and 2% were neutral toward PPL activity. The ripe fruit of Averrhoa carambola and the leaves of Archidendron jiringa (Jack) I.C Nielsen L. (jering), Cynometra cauliflora (nam-nam) and Aleurites moluccana (L.) Willd (candle nut/buah keras) had the highest (100%) anti-lipase activity and are equivalent to 0.11 µg orlistat/mL. Plants that stimulated lipase activity included Pimpinella anisum L. (aniseed/jintan manis), activating the enzyme by 186.5%. Kaempferol 3-O-rhamnoside was isolated from the ethyl acetate fraction of C. cauliflora leaves and found to be an active lipase inhibitor. The structure was elucidated using 1H-NMR, 13C-NMR and 2D-NMR analyses.

Effects of proanthocyanidins on porcine pancreatic lipase: Conformation, activity, kinetics and thermodynamics

The interactions between proanthocyanidins (PC) and porcine pancreatic lipase (PL) were investigated from variant aspects of lipase conformation, activity, kinetics, and thermodynamics. Results show that 34% inhibitory rate of PC on PL is achieved after about 30-min incubation, and the inhibitory rate increases with the increase of PC concentration and then plateaus at the PC/PL ratio of 200. Circular dichroism and fluorescence spectroscopic analyses demonstrate that PC decreases the α-helix content while increases the β-sheet content of PL, but does not change the microenvironment of Trp, and PC quenches the fluorescence of PL both dynamically and statically through the formation of PL–PC complex. PC induces PL aggregation and then stabilizes the lipase aggregates. Kinetic studies reveal that PC does not change the Km value while decreases the Vmax value, implying that PC non-competitively inhibits the PL activity.

Pancreatic lipase activity in emulsions containing seed meals: Effect of extrusion

AbstractThe effect of extrusion of soybean (Glycine max), yellow lupin (Lupinus luteus), and linseed (Linum usitatissimum) on the activity of porcine pancreatic lipase (PPL) was evaluated through pH‐Stat methodology with tributyrin emulsions in which the seed meals [extruded (E) and non‐extruded (NE)] were dispersed. The seed meals affected PPL activity in a concentration‐dependent fashion; at 2.3 mg/mL the meals reduced PPL activity (11.7–45.0% reduction) while the opposite was true (3.1–28.0% increase) at 6.8 mg/mL. PPL activity in the assays containing E‐lupin, E‐soybean and E‐linseed meals at 2.3 mg/mL was 109.7 and 11.3% higher and 25.5% lower than the activity in the emulsions containing the NE‐meals, respectively. The differences between the PPL activity in emulsions containing the extruded and NE‐meals could be due to changes in the emulsifying properties of the meals after extrusion; extrusion increased (10.2%) the emulsification capacity of lupin meal and for linseed meal this property was reduced (9.2%). In spite of the low PPL activity at low meal concentrations, the percentage of free fatty acids released after 30 min was similar to the theoretical maximum (66.6%) with two exceptions – NE‐soybean meal (59.5 ± 2.7%) and E‐linseed meal (57.9 ± 1.2%).Practical applications: Feed and food industries use plant protein sources that contain inhibitors of digestive enzymes. Various proteases inhibitors are inactivated during extrusion being less known the effect of extrusion on lipase inhibitors. Reduction of lypolysis rate, carried out mainly by pancreatic lipase in human and other animals, could influence feed and food consumption because satiety is controlled – at least in part – by undigested lipids. Our results show that extrusion can be used to reduce the inhibitory activity of lupin and soybean on PPL. On the other hand, extrusion of linseed increased the negative effect of this meal on PPL activity effect that could have applications in the development of food and ingredients for weight control.

Immobilization of lipase in organic solvent in the presence of fatty acid additives

In this study porcine pancreatic lipase (PPL) was covalently immobilized on cross-linked polyvinyl alcohol (PVA) in organic media in the presence of fatty acid additives in order to improve its immobilized activity. The effects of fatty acid additions to the immobilization media were investigated choosing tributyrin hydrolysis in water and ester synthesis by immobilized PPL in n-hexane. Various fatty acids which are also the substrates of lipases in esterification reactions were used as active site protecting agents during the immobilization process in an organic solvent. The obtained results showed that covalent immobilization carried out in the presence of fatty acids as protective ligands improved the hydrolytic and esterification activity of immobilized enzyme. A remarkable increase in activity of the immobilized PPL was obtained when octanoic acid was used as an additive and the hydrolytic activity was increased from 5.2 to 19.2 μmol min−1 mg−1 as compared to the non-additive immobilization method. With the increase of hydrolytic activity of immobilized lipase in the presence of octanoic acid, in an analogous manner, the rate of esterification for the synthesis of butyl octanoate was also increased from 7.3 to 26.3 μmol min−1 g−1 immobilized protein using controlled thermodynamic water activities with saturated salt solutions. In addition, the immobilized PPL activity was maintained at levels representing 63% of its original activity value after 5 repeated uses. The proposed method could be adopted for a wide variety of other enzymes which have highly soluble substrates in organic solvent such as other lipases and esterases.

Anti-Obesity effects of protopanaxdiol types of Ginsenosides isolated from the leaves of American ginseng ( Panax quinquefolius L.) in mice fed with a high-fat diet

Effects of protopanaxdiol (PDG) and protopanaxatriol (PTG) types of ginsenosides isolated from the leaves of American ginseng on porcine pancreatic lipase activity were determined in vitro. PDG inhibited the pancreatic lipase activity in a dose-dependent manner at the concentrations of 0.25–1 mg/ml. It inhibited hydrolysis of about 83.2% of triolein at about 1 mg/ml of PDG. However, PTG showed no inhibitory activity. Therefore, anti-obesity activity of PDG was evaluated in mice fed a high-fat diet. The results demonstrated that PDG was effective in preventing and healing obesity, fatty liver and hypertriglyceridemia in mice fed with a high-fat diet.

Development of an indirect method for measuring porcine pancreatic lipase in human duodenal fluid

Patients with exocrine pancreatic insufficiency are usually treated with porcine pancreatic enzymes but the bioavailability of these enzymes in the gut remains a matter of discussion. In order to determine the duodenal availability of porcine pancreatic lipase (PPL) present in pancreatic extracts (PE) taken orally, we developed a method for quantifying PPL in samples containing both PPL and human pancreatic lipase (HPL). Total pancreatic lipase activity measurements using the pH-stat technique and tributyrin as substrate were combined with an HPL-specific ELISA. Based on the known specific activity of the purified HPL, its activity was deduced from the ELISA measurements, and the PPL activity was obtained by subtracting the HPL activity from the total pancreatic lipase activity. This assay was established and validated using various samples containing pure PPL and recombinant HPL or PE, mixed or not with human duodenal juice. Samples collected in vivo from patients treated with PE were also tested. It was found that PPL did not affect the HPL ELISA, and the indirect PPL assay gave a measurement accuracy of 6.6% with the samples containing pure PPL and 10% with those containing PE. This assay was also used successfully to discriminate between PPL and the endogenous HPL present in the duodenal contents of patients with severe pancreatic insufficiency treated with PE. This method might provide a useful means of assessing the availability of PEs at their site of action, in the absence of a PPL-specific ELISA.

Pancreatic lipase inhibitory activity of taraxacum officinale in vitro and in vivo

Obesity has become a worldwide health problem. Orlistat, an inhibitor of pancreatic lipase, is currently approved as an anti-obesity drug. However, gastrointestinal side effects caused by Orlistat may limit its use. In this study the inhibitory activities of dandelion (Taraxacum officinale) against pancreatic lipase in vitro and in vivo were measured to determine its possible use as a natural anti-obesity agent. The inhibitory activities of the 95% ethanol extract of T. officinale and Orlistat were measured using 4-methylumbelliferyl oleate (4-MU oleate) as a substrate at concentrations of 250, 125, 100, 25, 12.5 and 4 µg/ml. To determine pancreatic lipase inhibitory activity in vivo, mice (n=16) were orally administered with corn oil emulsion (5 ml/kg) alone or with the 95% ethanol extract of T. officinale (400 mg/kg) following an overnight fast. Plasma triglyceride levels were measured at 0, 90, 180, and 240 min after treatment and incremental areas under the response curves (AUC) were calculated. The 95% ethanol extract of T. officinale and Orlistat, inhibited, porcine pancreatic lipase activity by 86.3% and 95.7% at a concentration of 250 µg/ml, respectively. T. officinale extract showed dose-dependent inhibition with the IC50 of 78.2 µg/ml. A single oral dose of the extract significantly inhibited increases in plasma triglyceride levels at 90 and 180 min and reduced AUC of plasma triglyceride response curve (p<0.05). The results indicate that T. officinale exhibits inhibitory activities against pancreatic lipase in vitro and in vivo. Further studies to elucidate anti-obesity effects of chronic consumption of T. officinale and to identify the active components responsible for inhibitory activity against pancreatic lipase are necessary.

백자인 추출물에 의한 pancreatic lipase의 저해 효과

Pancreatic lipase의 활성을 저해하는 물질을 탐색하고자 국내의 식용 또는 약용식물의 추출물을 대상으로 lipase 활성에 대한 저해능력이 있는 식물추출물은 탐색한 결과 대복피, 계혈등, 오배자 및 백자인의 식물추출물을 선정하였다. Pancreatic lipase에 대한 저해활성이 우수한 백자인으로부터 클로로포름 용매추출, 실리카겔 컬럼크로마토그라피, 세파덱스 LH-20 컬럼크로마토그라피와 고속액체크로마토그라피를 실시하여 pancreatic lipase에 대한 저해활성 물질로 TF-1, TF-2, TF-3를 분리하였다. 이들을 대상으로 porcine pancreatic lipase에 대한 저해효과를 측정한 결과, 활성물질 TF-1, TF-2, TF-3 및 orlistat의 porcine pancreatic lipase에 대한 <TEX>$IC_{50}$</TEX> 값은 각각 44.7, 98.7, 46.1 및 <TEX>$27.6{\mu}g/ml$</TEX>인 것으로 나타났다. 활성물질 TF-2와 orlistat의 경우에는 <TEX>$10{\mu}g/ml$</TEX>의 농도에서 NIH-3T3 L1의 지방세포로의 분화에도 억제효과가 있음을 입증하였다. The possible presence of inhibitors of pancreatic lipase (tricaylglycerol acylhydrolase EC 3.1.1.3) was screened from Korean traditional edible or medicinal herbs. Among tested herbs, Arecae pericarpium, Mucunae Caulis, Rhus javanica, Thujae orientalis were shown to have strong inhibitory effect against pancreatic lipase. Thujae orientalis was finally selected as a candidate for pancreatic lipase inhibitor. The extract of Thujae orientalis was showed selective inhibition on porcine pancreatic lipase activity. Active inhibitors, TF-1, TF-2, TF-3, were purified from an extract of Thujae orientalis, using chloroform extraction, followed by successive chromatography in silica gel and LH-20 and high performance liquid chromatography (HPLC). The <TEX>$IC_{50}$</TEX> values of TF-1, TF-2, TF-3 and orlistat were 44.7, 98.7, 46.1 and <TEX>$27.6{\mu}g/ml$</TEX>, respectively. And also the TF-2 and orlistat were shown to be inhibitory effect on the differentiation of preadipocyte NIH-3T3 L1 cells at a concentration of <TEX>$10{\mu}g/ml$</TEX>.

ε-Polylysine Inhibits Pancreatic Lipase Activity and Suppresses Postprandial Hypertriacylglyceridemia in Rats

Epsilon-polylysine (epsilon-PL) has been used as a food additive in Japan for many years. In this study, it inhibited human and porcine pancreatic lipase activity in substrate emulsions containing bile salts and phosphatidylcholine, in the concentration range of 10-1000 mg/L. At the same concentrations, it also destroyed the emulsifying activity, suggesting that lipase inhibitory activity and emulsion breakdown activity were associated. Epsilon-PL inhibited porcine pancreatic lipase activity and destroyed emulsion breakdown activity at 1000 mg/L in the substrate containing bile salts and phosphatidylcholine alone. Epsilon-PL did not inhibit lipase activity or affect emulsifying activity at 1000 mg/L in the substrates containing arabic gum and polyvinyl alcohol. A comparison of lipase inhibitory activity between epsilon-PL and three types of alpha-PL with differing polymerization rates was performed. The lipase inhibitory activity of epsilon-PL was not different from that of alpha-PL (44 lysine residues). Epsilon-PL maintained its inhibitory activity after incubation with trypsin, alpha-chymotrypsin and pepsin, whereas alpha-PL did not. The effect of epsilon-PL on postprandial hypertriacylglyceridemia was investigated in rats. The plasma triacylglycerol concentration in rats intragastrically administered > or =15 mg/kg of both fat emulsion and epsilon-PL was significantly lower at 2 and 3 h after administration than that in rats administered fat emulsion alone (P < 0.05). These results strongly suggest that epsilon-PL is able to suppress dietary fat absorption from the small intestine by inhibiting pancreatic lipase activity.