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PubMed2000

[Changes of lipoprotein lipase and hepatic lipase and their significance in gallstone formation in rabbit model].

This experiment was made to investigate the changes of lipoprotein lipase(LPL) and hepatic lipase (HL) activity and their effects on gallstone formation in rabbit model in which the stones were induced by high cholesterol diet. Activities of plasma LPL and HL were determined; other data including concentration of plasma lipoprotein cholesterol, concentration of bile cholesterol and bile acids were also obtained. The results showed that with the rabbits continuously fed on high cholesterol diet, LPL activity heightened markedly (P < 0.05), and HL activity increased gradually (3 and 4 weeks groups vs control group, P < 0.05). The changes of concentration of plasma VLDL-C and LDL-C were the same as that of LPL activity, but the concentration of plasma HDL-C, HDL2-C, HDL3-C and bile acids showed no significant changes (P > 0.05). These results suggest that the heightened activities of LPL and HL might make the liver take up more cholesterol, secrete it into the bile duct and hence accelerate gallstone formation.

Animals↗
PubMed1992

Selective measurement of lipoprotein lipase and hepatic triglyceride lipase in heparinized plasma from horses.

Affinity chromatography on heparin sepharose was used to identify 2 lipolytic enzymes in heparinized plasma from horses. One enzyme was typical of hepatic triglyceride lipase (HTGL), because it was resistant to inactivation by high concentrations of NaCl, and it did not require the addition of serum for activity. The other enzyme was identified as lipoprotein lipase (LPL), because of its inactivation at NaCl concentrations in excess of 0.2M, and its dependency on addition of serum as a source of apolipoprotein C-II activator. The enzymes were purified by 347-(HTGL) and 442- (LPL) fold, with yields of 54 and 58%, respectively. The partially purified enzymes were used to design incubation conditions that gave optimal activities for each enzyme in vitro. A selective assay was then developed for direct measurement of LPL and HTGL activities in heparinized plasma from horses. Analysis of HTGL took advantage of the almost complete inactivation of LPL when serum cofactor was excluded from the assay at the NaCl concentration that gave optimal HTGL activity. Prior incubation of heparinized plasma with sodium dodecyl sulfate to inhibit HTGL was necessary for measurement of LPL, because HTGL retained 67% of its activity at the NaCl concentration required for optimal LPL activity. Activity of each enzyme was measured in heparinized plasma from 12 Shetland ponies. The mean activity +/- SD for LPL was 3.22 +/- 1.04 mumol of fatty acids/ml of heparinized plasma/h (mumol of FA/ml/h. The mean activity for HTGL was 4.9 +/- 1.56 mumol of FA/ml/h. The performance of the assay was assessed by replicate analysis of pools of each enzyme with high and low activities.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

A missense (Asp250----Asn) mutation in the lipoprotein lipase gene in two unrelated families with familial lipoprotein lipase deficiency.

We have identified the molecular basis for familial lipoprotein lipase (LPL) deficiency in two unrelated families with the syndrome of familial hyperchylomicronemia. All 10 exons of the LPL gene were amplified from the two probands' genomic DNA by polymerase chain reaction. In family 1 of French descent, direct sequencing of the amplification products revealed that the patient was heterozygous for two missense mutations, Gly188----Glu (in exon 5) and Asp250----Asn (in exon 6). In family 2 of Italian descent, sequencing of multiple amplification products cloned in plasmids indicated that the patient was a compound heterozygote harboring two mutations, Arg243----His and Asp250----Asn, both in exon 6. Studies using polymerase chain reaction, restriction enzyme digestion (the Gly188----Glu mutation disrupts an Ava II site, the Arg243----His mutation, a Hha I site, and the Asp250----Asn mutation, a Taq I site), and allele-specific oligonucleotide hybridization confirmed that the patients were indeed compound heterozygous for the respective mutations. LPL constructs carrying the three mutations were expressed individually in Cos cells. All three mutant LPLs were synthesized and secreted efficiently; one (Asp250----Asn) had minimal (approximately 5%) catalytic activity and the other two were totally inactive. The three mutations occurred in highly conserved regions of the LPL gene. The fact that the newly identified Asp250----Asn mutation produced an almost totally inactive LPL and the location of this residue with respect to the three-dimensional structure of the highly homologous human pancreatic lipase suggest that Asp250 may be involved in a charge interaction with an alpha-helix in the amino terminal region of LPL. The occurrence of this mutation in two unrelated families of different ancestries (French and Italian) indicates either two independent mutational events affecting unrelated individuals or a common shared ancestral allele. Screening for the Asp250----Asn mutation should be included in future genetic epidemiology studies on LPL deficiency and familial combined hyperlipidemia.

Amino Acid Sequence↗
PubMed1990

Coexistence of abnormalities of hepatic lipase and lipoprotein lipase in a large family.

A large family is reported with familial hepatic triglyceride lipase (HTGL) deficiency and with the coexistence of reduced lipoprotein lipase (LPL) similar to the heterozygote state of LPL deficiency. The proband was initially detected because of hypertriglyceridemia and chylomicronemia. He was later demonstrated to have beta-VLDL despite an apo E3/E3 phenotype and the lack of stigmata of type III hyperlipoproteinemia. The proband had no HTGL activity in postheparin plasma. Two of his half-sisters had very low HTGL activity (39 and 31 nmol free fatty acids/min/ml; normal adult female greater than 44). His son and daughters had decreased HTGL activity (normal male and preadolescent female greater than 102), which would be expected in obligate heterozygotes for HTGL deficiency. Low HTGL activity was associated with LDL particles which were larger and more buoyant. Several family members, including the proband, had reduced LPL activity and mass less than that circumscribed by the 95% confidence-interval ellipse for normal subjects and had hyperlipidemia similar to that described in heterozygote relatives of patients with LPL deficiency. All the sibs with hyperlipidemia had a reduced LPL activity and mass, while subjects with isolated reduced HTGL (with normal LPL activity) had normal lipid phenotypes. Analysis of genomic DNA from these subjects by restriction-enzyme digestion revealed no major abnormalities in the structure of either the HTGL or the LPL gene. Compound heterozygotes for HTGL and LPL deficiency show lipoprotein physiological characteristics typical for HTGL deficiency, while their variable lipid phenotype is typical for LPL deficiency.

Adolescent↗
PubMed1977

Differential characteristics of purified hepatic triglyceride lipase and lipoprotein lipase from human postheparin plasma.

Evidence is presented that hepatic triglyceride lipase (H-TGL) and lipoprotein lipase (LPL), purified from human postheparin plasma, can each hydrolyze both glyceryl trioleate and palmitoyl-CoA. The average ratio of glyceryl trioleate/palmitoyl-CoA hydrolase activities, obtained with enzyme preparations from 15 human postheparin plasma samples was 1.30 (1.18-1.52) for H-TGL and 8.75 (7.45-10.25) for LPL. Albumin was identified as the serum cofactor required for the hydrolysis of palmitoyl-CoA by H-TGL. It protected this enzyme from inactivation by this substrate. In contrast, palmitoyl-CoA activated and protected LPL from denaturation by dilution and incubation at 25 degrees C. The effects of other detergents were investigated on glyceryl trioleate hydrolase activities of both enzymes. Sodium dodecyl sulfate (0.4 mM) and Trisoleate (0.4 mM), which also effectively activated and protected LPL against inactivation, had only moderate protective effect on H-TGL. Sodium dodecyl sulfate at a higher concentration (1 mM) produced little or no inhibition of LPL, while completely inactivating H-TGL. Conversely, sodium taurodeoxycholate (0.4 mM) protected and activated H-TGL, but had only moderate protective effect on LPL. Triton X-100 (0.1-0.8 mM) and egg lysolecithin (0.05-2 mM) also protected H-TGL, but not LPL. The very dissimilar effects of detergents on preparations on H-TGL and LPL may form the basis for the direct assay of each enzyme in the presence of the other.

Apolipoproteins↗
PubMedDate not supplied

In vivo and in vitro release of lipoprotein lipase and hepatic lipase by low molecular weight heparins.

The purpose of this study was to compare lipoprotein lipase (LPL) and hepatic lipase (HL) releasing activities of different low molecular weight heparins (LMWH) and of a standard heparin. In vivo, the injection of most LMWH led to a LPL and HL releasing activity inferior to that obtained with a standard heparin. The releasing of LPL by muscle in vitro and of HL by perfused liver was identical with both types of heparins, but in epididymal adipose tissue, LPL activity released by LMWH was generally higher than the activity released by unfractionated heparin. We have no explanation for this apparent contradiction between the in vivo and in vitro results.

Adipose Tissue↗
PubMed1988

Lipoprotein lipase, hepatic lipase and plasma lipolytic activity. Effects of heparin and a low molecular weight heparin fragment (Fragmin).

Heparin activates lipoprotein lipase (LPL) and hepatic lipase (HL), enhances plasma lipolytic activity and elevates plasma levels of free fatty acids (FFA). The metabolic consequences of this effect are controversial. In this study the plasma lipolytic effect of unfractionated heparin (mean molecular weight, MW, 12,000-15,000) was compared with that of a low molecular weight heparin (LMWH) fragment (Kabi 2165, Fragmin, mean MW 4000-6000). The comparisons which were carried out in vivo and in vitro in both man and rat were based on the antifactor Xa activity of the two heparins. After i.v. injection of LMWH the release of LPL activity was only half as great as with heparin and the increase in plasma FFA was significantly lower. The immediate release of HL activity was the same for both heparins, the release of LPL activity was dose-dependent and the elimination followed first-order kinetics. After subcutaneous administration, LMWH was absorbed faster than heparin but still had a negligible effect on plasma lipolysis. With simultaneous i.v. infusions of fat emulsion, glucose and heparin or LMWH to healthy subjects no different effects on fat oxidation were seen in spite of pathological increases in plasma FFA with heparin. Also, heat production from isolated adipocytes was not affected by heparin or LMWH. Enzyme release was greater with LMWH in tissue preparations of fat, skeletal muscle and heart muscle in vitro, however. In isolated fat cells no difference in the release of LPL was seen between the two heparins. In conclusion, the plasma lipolytic effect of LMWH is significantly weaker than that of heparin. The complex-binding between heparin and LPL is dependent on the degree of sulphation or ionic strength of the heparin. In the LPL-release from tissue preparations, the molecular size of the heparin is of greater significance, however. Regardless of the degree of plasma lipolytic activity of the two heparin preparations, the fat oxidation rate is not affected. Considering the toxic effects of high levels of plasma FFA, LMWH, with its weak lipolytic potential would appear to be preferable to heparin as an anticoagulant agent.

Adult↗
PubMed1985

Hepatic triglyceride lipase and lipoprotein lipase activities in post-heparin plasma of patients with various cancers.

The total post-heparin lipolytic activity (PHLA) and hepatic triglyceride lipase (HTGL) and lipoprotein lipase (LPL) activities in post-heparin plasma of patients with various cancers were measured. In patients with cancers, PHLA was similar to that of controls, but the HTGL activity was decreased and the LPL activity was increased. Thus, in cancer patients the ratios of HTGL to PHLA were lower, and the ratios of LPL to PHLA were higher than in controls. No correlation was found between the plasma lipid level and HTGL or LPL activity.

Aged↗
PubMed1987

Plasma kinetics of lipoprotein lipase and hepatic lipase activities induced by heparin and a low molecular weight heparin fragment.

Intravenous injections of conventional heparin and a low molecular weight heparin fragment (LMWH, mean molecular weight 4000-6000) were given to six male volunteers at doses of 10, 50 and 100 U (antiFXa)/kg body wt. The plasma kinetics of lipoprotein lipase (LPL) and hepatic lipase (HL) were analysed. The peak values, as well as the accumulated release of LPL activity, were dose dependent and were twice as high after heparin as after LMWH. The plasma half-life of LPL activity followed first order kinetics and was similar for both heparin preparations when given in comparable doses. The peak values and the plasma half-life of HL activity were the same for heparin and LMWH in the clinically relevant doses (50 and 100 U (antiFXa)/kg). Compared with LMWH, the total release of HL was twice as large after the heparin injections, possibly due to mobilization of an additional enzyme pool by the conventional heparin. It is concluded that the use of LMWH as an anticoagulant is associated with a lower plasma lipolytic activity than with standard heparin.

Adult↗
PubMed1985

[Lipoproteins, post-heparin lipoprotein lipase and hepatic triglyceride lipase in patients with and without severe hyperlipemia caused by alcoholism].

Because of the high incidence for development of a secondary hyperlipemia during chronic alcohol intake, this study was performed to look for a possible reason, why some patients produce severe hyperlipemia and other ones not. 15 male patients with chronic alcoholism (group I) who produce under influence of alcohol a secondary type-V hyperlipoproteinemia (type-V HLP) were compared with 15 male controls. Additionally, 8 male patients with chronic alcoholism (group II) who were normolipemic under alcohol abuse, and 7 male patients (group II) who had also produced type-V HLP under chronic alcohol abuse, but were teetotal since at least 6 months, were investigated. In comparison with controls, patients of group I showed significantly (p less than 0.01) increased plasma concentrations of very low-density lipoproteins (VLDL) and significantly decreased plasma concentrations of low-density lipoproteins (LDL), high-density lipoproteins2 (HDL2) and HDL3 (all p less than 0.01). Furthermore, the activities of postheparin lipoprotein lipase (LPL) and hepatic lipase (HTGL) were significantly decreased (both p less than 0.01). In patients of group III, the plasma concentrations of lipoproteins did not differ significantly from controls, but the activity of LPL was also significantly impaired (p less than 0.01), whereas the activity of HTGL was distinctly (p less than 0.01) increased. No significant difference between patients of group II and controls could be demonstrated. It is concluded that severe alcohol intake strongly impairs LPL in patients with chronic alcoholism. The pronounced increase of HTGL in patients of group III seems to protect these individuals from producing severe hyperlipemia under the influence of alcohol.

Adult↗
PubMedDate not supplied

[Comparison of the effect of homologous and heterologous albumin on the activity of lipoprotein lipase and liver triglyceride lipase in rabbit plasma].

Changes in the activity of blood plasma lipoprotein lipase (EC 3.1.1.34, LPL and hepatic triacylglycerol lipase EC 3.1.1.3, H-TGL) were studied in rabbits injected intravenously by homologous and heterologous albumins (bovine, fraction Y, Sigma, BSA) alone and in combination with heparin. Rabbit albumin enhanced the effect of heparin on the LPL activity, while heterologous protein, to the contrary, diminished it. The in vitro experiments showed that BSA caused a more distinct effect on the LPL activity as compared with that of rabbit albumin. The activity of H-TGL was not significantly altered under the influence of both proteins.

Animals↗
PubMed1979

A new method for the measurement of lipoprotein lipase in postheparin plasma using sodium dodecyl sulfate for the inactivation of hepatic triglyceride lipase.

Lipoprotein lipase (LPL) and hepatic triglyceride lipase (H-TGL) are lipolytic activities found in postheparin plasma. A simple and precise method for the direct determination of LPL in postheparin plasma is described. Pre-incubations of this plasma (45--60 min at 26 degrees C) with sodium dodecyl sulfate (35--50 mM) in 0.2 M Tris-HCl buffer, pH 8.2, results in the inactivation of H-TGL, while leaving LPL fully active. Direct determination of H-TGL is done in a separate aliquot of the same postheparin plasma sample using previously reported assay conditons that do not measure LPL. The sodium dodecyl sulfate-resistant lipolytic activity has the characteristics of LPL as judged by a) its activation by serum and by apolipoprotein C-II; b) its inactivation (over 90%) by 0.75 M NaCl; and c) its inactivation by a specific antiserum. No sodium dodecyl sulfate-resistant activity was found in postheparin plasma from a patient with LPL deficiency (primary type I hyperlipoproteinemia). An excellent correlation of values was obtained (r = 0.99) for 30 samples assayed after sodium dodecyl sulfate treatment and after immuno-inactivation of H-TGL. The intra-assay coefficient of variation was +/- 11% and 4% before and after normalization of values, respectively.

Female↗
PubMed1979

Effects of unsaturated fatty acids in phospholipids on the in vitro activation of the lipoprotein lipase and the triglyceride lipase.

The effects of different types of phospholipids on the lipoprotein lipase (LPL) and on the hepatic triglyceride lipase (TGLH) were studied by comparative in vitro incubation. Substrates were prepared by homogenization in glycerol of 3H-labelled triolein plus phosphatidylcholine (either dipalmitoyl PC, or ovolecithin or highly unsaturated PC, EPL Nattermann). Enzymes were obtained from rat adipose tissue, myocardium, lungs and liver and human adipose tissue and post-heparin plasma, respectively. The enzyme activities as determined in mmol/ml medium showed differences of highly statistical significance (p less than 0.001). In any tissue investigated the enzyme activities of LPL or TGLH followed the sequence: highly unsaturated PC (EPL) greater than ovo-lecithin greater than dipalmitoyl-lecithin. This was true for the enzymes of rat and human origin as well. It was concluded that the observed LPL and TGLH activation may account for the beneficial therapeutic effects of highly unsaturated phosphatidylcholine (EPL) in human hyperglyceridemias.

Adipose Tissue↗
PubMed1983

[Lipoproteins, apolipoproteins, lipoprotein lipase, hepatic triglyceride lipase and lecithin cholesterol acyltransferase in patients with nephrotic syndrome].

Chronic renal disease with secondary hyperlipidemia is highly atherogenic. In uremia and patients on chronic hemodialysis there is a high incidence of atherosclerotic complications whereas the incidence of atherosclerotic disease is relatively low in the nephrotic syndrome. This is surprising, as nephrosis produces type-II hyperlipidemia, which is usually highly atherogenic. In this study 10 patients (5 male, 5 female) with a newly diagnosed nephrotic syndrome were compared to 10 controls (5 male, 5 female). As laboratory parameters, lipids, lipoproteins (VLDL, IDL, LDL, HDL2 and HDL3 by rate zonal centrifugation) and the percentage composition of the major apolipoproteins in VLDL, HDL2 and HDL3, as well as lipoprotein lipase (LPL), hepatic lipase (HTGL) and lecithin-cholesterol-acyl-transferase (LCAT) were measured. In nephrotic patients significantly higher plasma levels of cholesterol, triglycerides, phospholipids, VLDL, IDL and LDL were found, whereas HDL-chol, HDL2 and HDL3 were unchanged. LPL and HTGL were both significantly impaired, whereas LCAT was distinctly increased. The percentage composition of apolipoproteins in HDL2 and HDL3 was normal. In nephrotic VLDL, apo-AI was distinctly increased at the expense of a decrease in apo-CII, and increased LCAT was explained by the relative rise of apo-AI in nephrotic VLDL. The increase in apo-AI in VLDL is discussed as a possible reason for the low atherogenic risk of secondary hyperlipidemia in nephrotic syndrome.

Adolescent↗
PubMed1984

Sensitive non-radioisotopic method for measuring lipoprotein lipase and hepatic triglyceride lipase in post-heparin plasma.

In this method for measuring lipoprotein lipase (LPL) and hepatic triglyceride lipase (H-TGL) in post-heparin plasma, we determine the released free fatty acids enzymically. After release, they are extracted by Dole 's method (J. Biol. Chem. 235: 2595-2599, 1960), solubilized with Triton X-100, then measured with an enzymic kit (NEFA Kit-K; Nippon Shoji Kaisha Ltd.) after residual turbidity is removed by centrifugation with chloroform. A 5-microL sample of post-heparin plasma suffices to measure the activity of LPL and H-TGL; thus the method is as sensitive as the radioisotopic method. Selective assay of LPL and H-TGL, by adding sodium dodecyl sulfate to inactivate H-TGL or NaCl to inactivate LPL, is also feasible. The mean activities +/- SD of LPL and H-TGL in plasma of normal healthy men were respectively 9.4 +/- 2.3 mumol/h per milliliter (157 +/- 38 U/L) and 20.1 +/- 10.4 (335 +/- 173 U) mumol/h per milliliter (U/L).

Adult↗
PubMed1996

[The colorimetric method for measuring activities of lipoprotein lipase and hepatic lipase in plasma].

To study the pathogenesis of hyperlipoidemia and atheromatosis and the metabolism of lipoprotein, we have developed a colorimetric method for simultaneously determining the activities of post-heparinplasma lipoprotein lipase (LPL) and hepatic lipase (HL). The intralipid was kept for LPL and HL at 37 degrees C, pH8.3 for 30 min, with 100 microliters post-heparin plasma. The LPL and HL in the post-heparin plasma could hydrolyse the triglyceride in intralipid into glycerine and free fatty acid (FFA). Determining the amount of FFA by copper-reagent method, we could measure the activities of LPL and HL. The kinetics of LPL and HL in post-heparin plasma was observed. K(m) values for LPL and HL were 0.9 mumol/L and 2.4 mumol/L respectively. The C. V. for LPL and HL were 4.5% (n = 4), 2.9% (n = 6) and 6.4% (n = 6), 4.8% (n = 6) respectively.

Animals↗
PubMed1997

Uptake of hypertriglyceridemic very low density lipoproteins and their remnants by HepG2 cells: the role of lipoprotein lipase, hepatic triglyceride lipase, and cell surface proteoglycans.

Hypertriglyceridemic very low density lipoproteins (HTG-VLDL, S(f) 60-400) are not taken up by HepG2 cells. However, addition of bovine milk lipoprotein lipase (LPL) at physiological concentrations markedly stimulates uptake. In the present study, we determined whether: a) LPL catalytic activity is required for uptake, b) LPL functions as a ligand, and c) cell surface hepatic triglyceride lipase (HL) and/or proteoglycans are involved. Incubation of HepG2 cells with HTG-VLDL plus LPL (8 ng/ml) increased cellular cholesteryl ester (CE) 3.5-fold and triglyceride (TG) 6-fold. Heat-inactivation of LPL abolished the effect. Addition of tetrahydrolipstatin (THL, an LPL active-site inhibitor) to HTG-VLDL + LPL, inhibited the cellular increase in both CE and TG by greater than 90%. Co-incubation of HTG-VLDL + LPL with heparin, heparinase, or heparitinase, blocked CE accumulation by 70%, 48%, and 95%, respectively, but had no effect on the increase in cellular TG. Pre-treatment of cells with 1 mM 4-methylumbelliferyl-beta-D-xyloside, (beta-xyloside) to reduce cell surface proteoglycans inhibited the increase in CE induced by HTG-VLDL + LPL by 78%. HTG-VLDL remnants, prepared in vitro and isolated free of LPL activity, stimulated HepG2 cell CE 2.8-fold in the absence of added LPL, a process inhibited with THL by 66%. Addition of LPL (8 ng/ml) to remnants did not further enhance CE accumulation. HepG2 cell HL activity, released by heparin, was inhibited 95% by THL. The amount of HL activity and immunoreactive mass, released by heparin, was reduced 50-60% in beta-xyloside-treated cells. These results indicate that physiological concentrations of LPL promote HepG2 cell uptake of HTG-VLDL primarily due to remnant formation and that LPL does not play a major role as a ligand. HL activity and cell surface proteoglycans significantly enhance the subsequent uptake of VLDL remnants.

Animals↗
PubMed2002

Plant lipases: biocatalyst aqueous environment in relation to optimal catalytic activity in lipase-catalyzed synthesis reactions.

Adsorption and desorption isotherms of two commercial enzyme preparations of papain and bromelain were determined with a Dynamic Vapor System. The Guggenheim-Anderson-deBoer (GAB) modeling of the obtained sorption isotherms allowed the definition of different levels of hydration of those samples. Afterward, these enzyme preparations were used as biocatalysts in water and solvent-free esterification and alcoholysis reactions. The evolution of the obtained fatty acid ester level as a function of the initial hydration level of the biocatalyst, i.e., thermodynamic water activity (a(w)) and water content, was studied. The results show an important correlation between the initial hydration level of the biocatalyst and its catalytic activity during the lipase-catalyzed synthesis reactions. Thus, the Carica papaya lipase (crude papain preparation) catalytic activity is highly dependent on the biocatalyst hydration state. The optimized synthesis reaction yield is obtained when the a(w) value of the enzyme preparation is stabilized at 0.22, which corresponds to 2% water content. This optimal level of hydration occurs on the linear part of the biocatalyst's sorption isotherm, where the water molecules can form a mono- or multiple layer with the protein network. The synthesis reaction yield decreases when the a(w) of the preparation is higher than 0.22, because the excess water molecules modify the system equilibrium leading to the reverse and competitive reaction, i.e., hydrolysis. These results show also that an optimal storage condition for the highly hydrophilic crude papain preparation is a relative humidity strictly lower than 70% to avoid an irreversible structural transition leading to a useless biocatalyst. Concerning the bromelain preparation, no effect of the hydration level on the catalytic activity during esterification reactions was observed. This biocatalyst has too weak a catalytic activity which makes it difficult to observe any differences. Furthermore, the bromelain preparation is far more hydrophobic as it adsorbs only 18 g of water per 100 g of dry material at a(w) around 0.90. No deliquescence of this enzymatic preparation is observed at this a(w) value.

Alcohols↗