Jacek Dulęba - Academia.edu (original) (raw)
Papers by Jacek Dulęba
Background: Many OTC drugs are available in non-pharmacy outlets, and as such the risk of overuse... more Background: Many OTC drugs are available in non-pharmacy outlets, and as such the risk of overuse and/or improper use of this class of drugs is more likely. In light of this observation, our study was conducted with the aim of exploring opinions on non-pharmaceutical distribution among Polish patients. This study was a part of an informative project to educate patients about the possible risks associated with the use of OTC medicines. Methods: We conducted a cross-sectional study among Polish patients in which we used an authorial questionnaire, previously tested via content, face validity, and a pilot study. The questionnaire was distributed both electronically and in a traditional form. Results: ‘Time saving’ had a statistically significant role in the patient’s decision about purchasing drugs in a non-pharmacy outlet (p = 0.0052; R = 0.276994). The lack of a pharmacist’s consultation/advice (p = 0.0072; R = −0.3290490), improper storage (p = 0.0044; R = −0.238246), risk of overdo...
Medical Research Journal
Metabolic chiral inversion of 2-arylpropionic acid derivatives (profens) ABSTRACT 2-arylpropionic... more Metabolic chiral inversion of 2-arylpropionic acid derivatives (profens) ABSTRACT 2-arylpropionic acid derivatives (profens) are one of the most popular anti-inflammatory, analgesic, and antipyretic drugs. They belong to a group of nonsteroidal anti-inflammatory drugs (NSAID) and exhibit metabolic chiral inversion. Enantiomers of these chiral drugs are often characterised by different pharmacological activity. It is estimated that the values of metabolic chiral inversion of (R)-ibuprofen in humans are between 35 and 70%, depending on the condition of the liver and the intake of other medicines, while (R)-flurbiprofen undergoes chiral metabolic inversion to its opposed (S) form only in small range. The described phenomenon in the case of (R)-ketoprofen is limited to a maximum of around 10%. The metabolic chiral inversion is associated with potentially important pharmacotherapeutic and toxicological consequences, and so an attempt was made to analyse this phenomenon for the most commonly used drugs from the profens group.
Catalysts
Immobilized enzymatic catalysts are widely used in the chemical and pharmaceutical industries. As... more Immobilized enzymatic catalysts are widely used in the chemical and pharmaceutical industries. As Candida antarctica lipase B (CALB) is one of the more commonly used biocatalysts, we attempted to design an optimal lipase-catalytic system. In order to do that, we investigated the enantioselectivity and lipolytic activity of CALB immobilized on 12 different supports. Immobilization of lipase on IB-D152 allowed us to achieve hyperactivation (178%) in lipolytic activity tests. Moreover, the conversion in enantioselective esterification increased 43-fold, when proceeding with lipase-immobilized on IB-S861. The immobilized form exhibited a constant high catalytic activity in the temperature range of 25 to 55 °C. Additionally, the lipase immobilized on IB-D152 exhibited a higher lipolytic activity in the pH range of 6 to 9 compared with the native form. Interestingly, our investigations showed that IB-S500 and IB-S60S offered a possibility of application in catalysis in both organic and aq...
Current Organic Chemistry
: Lipases in the native or immobilized form have commonly used as catalysts in the chemical and p... more : Lipases in the native or immobilized form have commonly used as catalysts in the chemical and pharmaceutical industry. One of the widely available enzyme catalysts on the market is lipase from Burkholderia cepacia (BCLs), previously called Pseudomonas cepacia (PCLs). Above enzyme is applied, among others, in the stereoselective acylation of molecules to achieve chiral pure enantiomers of drugs or their building blocks. In this study, Amano lipase PS (APS-BCL), which is a commercial one of lipase from Burkholderia cepacia (BC) was tested. The lipolytic activity of APS-BCL by hydrolysis of vegetable oils and enantioselective activity of APS-BCL by the kinetic resolution of (R,S)-1-phenylethanol with using isopropenyl acetate as an acyl donor were evaluated. An effect of reaction media with different logP values (t-butyl methyl ether, dichloromethane, diisopropyl ether, toluene, cyclohexane, n-hexane, isooctane and n-heptane) on the enantioselective activity of lipase was also studied. The high value of the enantiomeric ratio (E =308.5) with the utilize of isopropenyl acetate was achieved. Whereas, the best reaction medium turned out to be diisopropyl ether, C =47.9%, eep =98%, ees =90%, after 24 h of incubation. Moreover, the influence of ω6/ω9 polyunsaturated fatty acids (PUFAs) ratio in commercial (peanut, camelina, rape, pumpkin seed, walnut, sesame, avocado, rice, corn, black cumin, hemp, safflower, grape seed) oils on lipase activity were investigated. For the first time, the cut-off limit of ω6/ω9 ratio was proposed. The ratio equal to or higher than 2.3 allows achieving higher lipolytic activity.
Medical Research Journal
Lipases are commonly applied in the pharmaceutical and chemical industry, especially in immobiliz... more Lipases are commonly applied in the pharmaceutical and chemical industry, especially in immobilized form. The use of immobilized lipases facilitates the design of reactors and control of reactions, for example, fast stopping the reaction. The immobilization procedure should increase the stability of the lipase and its activity, as well as be simple and efficient. Lipase B from Candida antarctica (CAL-B) is an enzyme from the lipase group, isolated from the Candida antarctica species. CAL-B has the highest activity in non-polar organic solvents, such as hexane and toluene, and the lowest in polar solvents, e.g. acetonitrile. Due to its hydrolytic properties, this enzyme degrades triglycerides of fatty acids to free fatty acids (FFA) and glycerol. Described lipase is often immobilized, in the aim to increase enantioselective and lipolytic activity. The kinetic and dynamic resolution with the application of lipase is one of the ways in obtaining an enantiopure form of the drugs, which usually are more effective and safer for the patient. The CAL-B could be also applied in the kinetic resolution of compounds being building blocks, derivates of drugs or conjugated forms. Furthermore, the CAL-B is used in the reactions in receiving of organic compounds, which are the natural origin, especially vegetable. Based on the presented data, it can be concluded, that CAL-B is an enzyme with a wide application in the biosynthesis of compounds with therapeutic activity.
Background: Many OTC drugs are available in non-pharmacy outlets, and as such the risk of overuse... more Background: Many OTC drugs are available in non-pharmacy outlets, and as such the risk of overuse and/or improper use of this class of drugs is more likely. In light of this observation, our study was conducted with the aim of exploring opinions on non-pharmaceutical distribution among Polish patients. This study was a part of an informative project to educate patients about the possible risks associated with the use of OTC medicines. Methods: We conducted a cross-sectional study among Polish patients in which we used an authorial questionnaire, previously tested via content, face validity, and a pilot study. The questionnaire was distributed both electronically and in a traditional form. Results: ‘Time saving’ had a statistically significant role in the patient’s decision about purchasing drugs in a non-pharmacy outlet (p = 0.0052; R = 0.276994). The lack of a pharmacist’s consultation/advice (p = 0.0072; R = −0.3290490), improper storage (p = 0.0044; R = −0.238246), risk of overdo...
Medical Research Journal
Metabolic chiral inversion of 2-arylpropionic acid derivatives (profens) ABSTRACT 2-arylpropionic... more Metabolic chiral inversion of 2-arylpropionic acid derivatives (profens) ABSTRACT 2-arylpropionic acid derivatives (profens) are one of the most popular anti-inflammatory, analgesic, and antipyretic drugs. They belong to a group of nonsteroidal anti-inflammatory drugs (NSAID) and exhibit metabolic chiral inversion. Enantiomers of these chiral drugs are often characterised by different pharmacological activity. It is estimated that the values of metabolic chiral inversion of (R)-ibuprofen in humans are between 35 and 70%, depending on the condition of the liver and the intake of other medicines, while (R)-flurbiprofen undergoes chiral metabolic inversion to its opposed (S) form only in small range. The described phenomenon in the case of (R)-ketoprofen is limited to a maximum of around 10%. The metabolic chiral inversion is associated with potentially important pharmacotherapeutic and toxicological consequences, and so an attempt was made to analyse this phenomenon for the most commonly used drugs from the profens group.
Catalysts
Immobilized enzymatic catalysts are widely used in the chemical and pharmaceutical industries. As... more Immobilized enzymatic catalysts are widely used in the chemical and pharmaceutical industries. As Candida antarctica lipase B (CALB) is one of the more commonly used biocatalysts, we attempted to design an optimal lipase-catalytic system. In order to do that, we investigated the enantioselectivity and lipolytic activity of CALB immobilized on 12 different supports. Immobilization of lipase on IB-D152 allowed us to achieve hyperactivation (178%) in lipolytic activity tests. Moreover, the conversion in enantioselective esterification increased 43-fold, when proceeding with lipase-immobilized on IB-S861. The immobilized form exhibited a constant high catalytic activity in the temperature range of 25 to 55 °C. Additionally, the lipase immobilized on IB-D152 exhibited a higher lipolytic activity in the pH range of 6 to 9 compared with the native form. Interestingly, our investigations showed that IB-S500 and IB-S60S offered a possibility of application in catalysis in both organic and aq...
Current Organic Chemistry
: Lipases in the native or immobilized form have commonly used as catalysts in the chemical and p... more : Lipases in the native or immobilized form have commonly used as catalysts in the chemical and pharmaceutical industry. One of the widely available enzyme catalysts on the market is lipase from Burkholderia cepacia (BCLs), previously called Pseudomonas cepacia (PCLs). Above enzyme is applied, among others, in the stereoselective acylation of molecules to achieve chiral pure enantiomers of drugs or their building blocks. In this study, Amano lipase PS (APS-BCL), which is a commercial one of lipase from Burkholderia cepacia (BC) was tested. The lipolytic activity of APS-BCL by hydrolysis of vegetable oils and enantioselective activity of APS-BCL by the kinetic resolution of (R,S)-1-phenylethanol with using isopropenyl acetate as an acyl donor were evaluated. An effect of reaction media with different logP values (t-butyl methyl ether, dichloromethane, diisopropyl ether, toluene, cyclohexane, n-hexane, isooctane and n-heptane) on the enantioselective activity of lipase was also studied. The high value of the enantiomeric ratio (E =308.5) with the utilize of isopropenyl acetate was achieved. Whereas, the best reaction medium turned out to be diisopropyl ether, C =47.9%, eep =98%, ees =90%, after 24 h of incubation. Moreover, the influence of ω6/ω9 polyunsaturated fatty acids (PUFAs) ratio in commercial (peanut, camelina, rape, pumpkin seed, walnut, sesame, avocado, rice, corn, black cumin, hemp, safflower, grape seed) oils on lipase activity were investigated. For the first time, the cut-off limit of ω6/ω9 ratio was proposed. The ratio equal to or higher than 2.3 allows achieving higher lipolytic activity.
Medical Research Journal
Lipases are commonly applied in the pharmaceutical and chemical industry, especially in immobiliz... more Lipases are commonly applied in the pharmaceutical and chemical industry, especially in immobilized form. The use of immobilized lipases facilitates the design of reactors and control of reactions, for example, fast stopping the reaction. The immobilization procedure should increase the stability of the lipase and its activity, as well as be simple and efficient. Lipase B from Candida antarctica (CAL-B) is an enzyme from the lipase group, isolated from the Candida antarctica species. CAL-B has the highest activity in non-polar organic solvents, such as hexane and toluene, and the lowest in polar solvents, e.g. acetonitrile. Due to its hydrolytic properties, this enzyme degrades triglycerides of fatty acids to free fatty acids (FFA) and glycerol. Described lipase is often immobilized, in the aim to increase enantioselective and lipolytic activity. The kinetic and dynamic resolution with the application of lipase is one of the ways in obtaining an enantiopure form of the drugs, which usually are more effective and safer for the patient. The CAL-B could be also applied in the kinetic resolution of compounds being building blocks, derivates of drugs or conjugated forms. Furthermore, the CAL-B is used in the reactions in receiving of organic compounds, which are the natural origin, especially vegetable. Based on the presented data, it can be concluded, that CAL-B is an enzyme with a wide application in the biosynthesis of compounds with therapeutic activity.