Lower Free Fatty Acid Research Articles

Pour Point Depression of Waxy Crude Oil Using Unmodified African Pear (Dacryodes edulis) Seed Oil

The pour point depression of a Nigeria waxy crude oil was investigated using unmodified African pear seed oil. Crude oil sample collected from a marginal field in Delta state was analyzed for its physiochemical parameters such as; specific gravity, API, kinematic viscosity, pour point and wax content. African pear seeds sourced from choba Port Harcourt were extracted of their oil content and the oil was analyzed for some oil quality parameters such as; free fatty acid (FFA), acid value, saponification value and iodine value. The results showed a crude oil of high wax content and extracted oil of low FFA and high saponification and iodine values. The waxy crude oil was dosed with the unmodified African pear seed oil of concentrations 0.1ml, 0.2ml and 0.3 ml. The result showed no reduction in the pour point of the crude oil at all concentrations. Therefore the African pear seed oil cannot be used as a pour point depressant in its pure state.

Ecological adaptations of amphibians to environmental changes along an altitudinal gradient (Case Study: Bufo gargarizans) from phenotypic and genetic perspectives

BackgroundOrganisms have evolved a range of phenotypic and genetic adaptations to live in different environments along an altitudinal gradient. Herein, we studied the widely distributed Chinese toad, Bufo gargarizans, as a model and used an integrated phenotype-genotype approach to assess adaptations to different altitudinal environments.ResultsComparison of populations from four altitudes (50 m, 1200 m, 2300 m, and 3400 m) showed more effective defenses among high-altitude toads. These included thickened epidermis, more epidermal capillaries and granular glands, greater gland size in skin, and higher antioxidant enzyme activities in plasma. High-altitude toads also showed increased erythrocytes and hematocrit and elevated hemoglobin concentration, potentially improving oxygen delivery. Elevated altitude led to a metabolic shift from aerobic to anaerobic metabolism, and high-altitude populations favored carbohydrates over fatty acids to fuel for energy metabolism. Differentially expressed genes were associated with adaptive phenotypic changes. For instance, expression of genes associated with fatty acid metabolism showed greater suppression at high altitude (3400 m), consistent with decreased flux of β-hydroxybutyric acid and lower free fatty acids levels. Moreover, down-regulation of genes involved in carbon metabolism processes at high altitude (3400 m) were coincident with reduced TCA cycle flux. These results suggest that high-altitude toads adopt a metabolic suppression strategy for survival under harsh environmental conditions. Moreover, the hypoxia-inducible factor signaling cascade was activated at high altitude.ConclusionsCollectively, these results advance our comprehension of adaptation to high-altitude environments by revealing physiological and genetic mechanisms at work in Chinese toads living along altitudinal gradients.

Supercritical CO2 as a green technology for carotenoids-rich virgin palm oil production: Process optimization, kinetics and thermodynamics modeling

The experimental conditions of supercritical carbon dioxide (scCO2) extraction of virgin palm oil (VPO) from oil palm mesocarp fiber (OPMF) were optimized using the Response Surface Methodology (RSM). Results showed that a maximum of 28.68% of VPO extraction was obtained at the optimal experimental conditions of scCO2 extraction: pressure of 31MPa, temperature of 340K, and extraction time of 80min. The second-order rate equation, Arrhenius equation and Eyring theory were employed to assess the kinetics behaviour, activation energy and thermodynamics behaviour of scCO2 extraction of VPO from oil palm mesocarp fiber. The lower activation energy value (12.17kJ/mol) of scCO2 for the extraction of VPO from OPMF indicates that the scCO2 extraction technology is less dependent on temperature during the extraction of VPO from OPMF. The physicochemical properties and fatty acids compositions analyses reveal that the scCO2 extracted VPO contains high carotenoids content (982μg/g), low free fatty acids content (0.31wt.%), higher oxidative stability and higher unsaturated fatty acids content.

In vitro gastrointestinal digestibility and lipid oxidation of fish oil-in-water emulsions: Influence of different EPA/DHA ratios

The long-chain omega-3 polyunsaturated fatty acids (ω-3 PUFAs) eicosatetraenoic acid (EPA) and docosahexaenoic acid (DHA) are known to play roles in supporting human health, primarily by reducing inflammation and promoting its resolution. In this study, the impacts of EPA/DHA ratios (5.13/1, 2.45/1,1.34/1) on lipid oxidation and digestion behaviors were explored using an in vitro digestion model. Emulsions were characterzied by droplet size, zeta-potential as well as microstructure. Additionally, the release of free fatty acids (FFAs), lipid hydroperoxides (LPO) and thiobarbituric acid reactive substance (TBARS) were also investigaed throughout simulated digestion phases. Notably, for all EPA/DHA ratios, from saliva fluid to gastric fluid, droplet size was slightly changed, accompanied by a significant decrease in absolute zeta-potential, followed by an increase in both parameters after intestinal digestion. Emulsions with the lowest ratio of EPA/DHA (i.e., 1.34/1) exhibited lower FFA release compared to those with higher ratios (i.e., 5.13/1 and 2.45/1). Conversely, the lowest EPA/DHA ratio increased oxidation during the intestinal phase, as indicated by elevated LPO and TBARS levels. This study clearly suggests that EPA/DHA ratios influence the oxidative stability of fish oil emulisions during digestion and provides useful information to formulate fish oil supplementation that improves in vivo oxidative status.

Chondroitin Sulfate from Halaelurus burgeri Skin Inhibits Hepatic Endoplasmic Reticulum Stress and Inflammation, and Regulates Gut Microbiota.

Previous study has demonstrated the chemical structure of chondroitin sulfate (CHS) from Halaelurus burgeri skin and its effects on insulin resistance. However, the precise impact of this phenomenon on endoplasmic reticulum (ER) stress and inflammation, which contribute to insulin resistance, remains unclear. This study is to investigate the impact of CHS on ER stress, inflammatory response and signaling, and gut microbiota in high-fat diet (HFD)-fed mice. HFD-fed C57BL/6J mice receive dietary gavage intervention of CHS for 18 weeks. Blood, liver tissue, and feces are harvested for further investigation. Results show that CHS inhibits ER stress, accompanied by lowered blood glucose, nitric oxide (NO), reactive oxygen (ROS), and free fatty acids (FFA) levels, and increases hepatic glycogen accumulation. Moreover, hepatic inflammation is improved by CHS treatment via inactivation of Toll-like receptor 4 (TLR4) signaling and its downstream c-jun N-terminal kinase (JNK) and nuclear factor kappa B (NFκB) pathways. Additionally, CHS regulates gut microbiota, particularly the decline in the Firmicutes to Bacteroidetes ratio. CHS also lowers fecal lipopolysaccharide and elevates several fecal short chain fatty acids. These findings suggest that CHS from H. burgeri skin may be an alternative functional food supplement for anti-ER stress, anti-inflammtion, and regulation of gut microbiota.

The U -shape relationship between free fatty acid level and adverse outcomes in coronary artery disease patients with hypertension: evidence from a large prospective cohort study

BackgroundEvidence is scarce on the effect of free fatty acid (FFA) level in the prognosis of coronary artery disease (CAD) patients with hypertension. This study.MethodsA large prospective cohort study with a follow-up period of average 2 years was conducted at Xinjiang Medical University Affiliated First Hospital from December 2016 to October 2021. A total of 10,395 CAD participants were divided into groups based on FFA concentration and hypertension status, and then primary outcome mortality and secondary endpoint ischemic events were assessed in the different groups.ResultsA total of 222 all-cause mortality (ACMs), 164 cardiac mortality (CMs), 718 major adverse cardiovascular events (MACEs) and 803 major adverse cardiovascular and cerebrovascular events (MACCEs) were recorded during follow-up period. A nonlinear relationship between FFA and adverse outcomes was observed only in CAD patients with hypertension. Namely, a “U -shape” relationship between FFA levels and long-term outcomes was found in CAD patients with hypertension. Lower FFA level (< 310 µmol/L), or higher FFA level (≥ 580 µmol/L) at baseline is independent risk factors for adverse outcomes. After adjustment for confounders, excess FFA increases mortality (ACM, HR = 1.957, 95%CI(1.240–3.087), P = 0.004; CM, HR = 2.704, 95%CI(1.495–4.890, P = 0.001) and MACE (HR = 1.411, 95%CI(1.077–1.848), P = 0.012), MACCE (HR = 1.299, 95%CI (1.013–1.666), P = 0.040) prevalence. Low levels of FFA at baseline can also increase the incidence of MACE (HR = 1.567,95%CI (1.187–2.069), P = 0.002) and MACCE (HR = 1.387, 95%CI (1.070–1.798), P = 0.013).ConclusionsBaseline FFA concentrations significantly associated with long-term mortality and ischemic events could be a better and novel risk biomarker for prognosis prediction in CAD patients with hypertension.Trial registrationThe details of the design were registered on https://www.chictr.org.cn/ (Identifier NCT05174143).

Fasting triglyceride concentrations are associated with markers of lipid metabolism and glucose homeostasis in healthy, non-obese dogs in lean and overweight condition.

Serum triglyceride concentrations increase in dogs with obesity, which is typically assessed by body condition score (BCS), however little is known about changes that take place in non-obese dogs in overweight condition. Further, the associations of triglyceride levels with other markers of energy homeostasis are poorly characterised in healthy animals. The present study aimed to evaluate associations between both BCS and triglyceride concentrations with other markers of lipid and glucose metabolism in healthy, non-obese dogs, as well as to assess whether these markers change significantly in non-obese dogs with overweight as compared to their lean counterparts. Serum concentrations of cholesterol, free fatty acids, triglycerides, insulin, glucose and fructosamine were measured in 532 healthy, client-owned dogs, assigned either to 'lean' (BCS: 3-5) or 'overweight' (BCS: 6-7) categories. Generalised linear mixed models were used to assess associations between BCS categories, triglyceride concentrations and other variables, correcting for the effect of breed. Compared with lean dogs, overweight dogs had a greater serum cholesterol concentration (95% CI, 5.3-6.2 mmol/L or 205-237 mg/dL versus 5.1-5.4 mmol/L or 198-210 mg/dL, p = 0.0032), insulin concentration (95% CI, 17.5-22.1 μU/ml versus 16.7-18.0 μU/ml, p = 0.0374) and were older (95% CI, 4.0-5.3 versus 3.4-3.7 years, p = 0.0005). Triglyceride concentrations were positively associated with fructosamine (r 2 = 0.31, p = 0.0012), cholesterol (r 2 = 0.25, p < 0.0001), insulin (r 2 = 0.14, p = 0.0030) and glucose (r 2 = 0.10, p = 0.0014) concentrations, and negatively associated with free fatty acid concentrations (r 2 = 0.11, p < 0.0001). However, there was no association between triglyceride concentrations and age. In conclusion, both BCS and triglyceride concentrations were associated with other markers of glucose and lipid metabolism in non-obese healthy dogs, amongst which those with overweight showed metabolic changes as compared to their lean counterparts. Triglyceride concentrations were associated with an increase in insulin and fructosamine concentrations that might reflect an early-phase impairment in glucose tolerance which, surprisingly, was concurrent with lower basal free fatty acid concentrations.

Metabolic responses to albumin deficiency differ distinctly between partial and full ablation of albumin expression in mice

It had been observed that homozygous albumin knockout mice (Alb−/−) exhibit low plasma free fatty acid (FFA) concentration and improved blood glucose regulation. However, it was not yet known to what extent heterozygous albumin knockout (Alb+/−) mice would display a similar phenotype. Alb−/−, Alb+/−, and wild-type (WT) female mice were studied on a low-fat diet (LFD) or high-fat diet (HFD). On both diets, decreased plasma FFA concentration, and improved glucose tolerance test were observed in Alb−/−, but not in Alb+/−, compared to WT. Plasma adiponectin concentration showed greater elevation in Alb−/− than Alb+/−. Consistent with that, adiponectin gene expression was significantly higher in Alb−/− mice than in Alb+/− and WT mice. A dose-dependent response was observed for hepatic Acadl gene expression showing higher Acadl gene expression in Alb−/− mice than in Alb+/− and WT mice. In conclusion, although female Alb+/− mice exhibited some slight differences from WT mice (e.g., increased plasma adiponectin and hepatic Acadl gene expression), Alb+/− mice did not exhibit improved glucoregulation in comparison to WT mice, indicating that a minor suppression of albumin expression is not sufficient to improve glucoregulation. Furthermore, it is now clear that although the response of female mice to HFD might be unique from how males generally respond, still the complete albumin deficiency in Alb−/− mice and the associated FFA reduction is capable of improving glucoregulation in females on this diet. The present results have implications for the role of albumin and FFA in the regulation of metabolism.

Characteristics of Arabica and Robusta Spent Coffee Grounds Oil Extract with Different Solvents

Abstract High coffee consumption contributes to waste, such as spent coffee grounds (SCG). SCG contains up to 20 % oil, with the main oil content being linoleic and palmitic fatty acids. So, SCG has the potential to be used in valuable products. This study aims to characterise Arabica and Robusta SCG oil using maceration methods with different solvents (hexane, ethanol, and petroleum benzene) to obtain maximum coffee oil as an alternative. Arabica and Robusta SCG characterisation comprises the composition content, oil yield, fatty acid profile, and viscosity. The results showed that Arabica SCG oil yield was higher than Robusta, with hexane becoming the most efficient solvent to extract the oil, with 28,87% and 25,57%, respectively. The lowest free fatty acid (FFA) found in Arabica SCG oil extract using hexane is 1,95%, which consists of palmitic acid (9.41%), linoleic acid (5.37%), and stearic acid (4.7%). The highest viscosity is Arabica SCG oil extract using hexane, which is caused by the large amount of long-chain fatty acids extracted by the solvent, such as palmitic acid and linoleic acid. The FFA content of Arabica SCG oil extract using hexane has the potential to be edible oil (cooking oil) and biodiesel.

Effect of alterations in phospholipids and free fatty acids on aroma-active compounds in instant-boiled chuck tender, sirloin and silverside beef

Beef flavor profiles are strongly influenced by cooking methods and lipid composition. However, the effect of instant-boiling on the aroma of different beef slices was unclear. This study investigated the lipid profiles and instant-boiling volatile profiles of chuck tender (M. Supraspinatus), sirloin (M. Longissimus dorsi) and silverside (M. Biceps femoris). Quantitative lipidomics identified 336 lipid molecular species, of which 84–112 were quantitatively different among the three beef slices. Sirloin had lower phosphatidylcholine, phosphatidylinositol, phosphatidylglycerol and free fatty acids than chuck tender and silverside. The unsaturated fatty acid acyl chains in phosphatidylethanolamine differed significantly. Solid phase microextraction-gas chromatography-olfactometry-mass spectrometry (SPME-GC-O-MS) identified hexanal, octanal, nonanal, decanal, (E)-2-octenal, (E)-2-nonenal, (E)-2-undecenal, (E,E)-2,4-nonadienal, (E,E)-2,4-decadienal, 1-octen-3-ol, 2-pentylfuran and acetoin as the aroma-active compounds of instant-boiled beef. Unsaturated free fatty acids and phosphatidylglycerols with unsaturated fatty acid residues positively correlated with the aroma-active compounds and might be crucial in flavor differences among the three beef slices. These findings provide greater understanding of the lipid and instant-boiling aroma-active compound profiles in chuck tender, sirloin and silverside, and reflect the suitability of different beef slices for instant-boiling from the aroma perspective.

Oilseed viability: A crucial factor for the success of the biodiesel industry

The oil derived from the seeds of the pongamia plant (Pongamia pinnata) has the potential to produce biodiesel. However, pongamia oil's high viscosity and conradson carbon residue make it unsuitable to use directly as a fuel in the already existing diesel engines. As a result, the experiments were carried out to determine the effectiveness of employing pongamia seeds with varying levels of seed viability for biodiesel production through transesterification process. The study looked at the relationship between seed physiological characteristics and extracted oil qualities in view of production of biodiesel through single step trasesterification process. The decreased seed viability was reflected in feedstock qualities such as free fatty acids (FFAs), saponification value (SV), iodine value (IV), cetane number (CN), and antioxidant enzyme activity. The pongamia seed lot exhibited >60 % germination rates contained oil with low FFAs, low SV and high IV. The oil's low free fatty acid content (1.8 %) aids biodiesel production via a single-step alkali-based trans-esterification method. Thus, seed lots with higher viability enhance fuel properties, but decreasing FFAs in pongamia oil increases fuel production capabilities of seeds. Seeds with good viability exhibited lower oil oxidation potential due to higher antioxidant enzyme activity. The rapid viability evaluation test kit can be used at any stage of seed storage to determine whether oilseeds are suitable for biodiesel production. These findings will enable energy plantation growers to increase their profits by providing the biodiesel sector with high-quality feedstock.

The association between serum free fatty acid levels and neurological outcomes in out-of-hospital cardiac arrest patients: A prospective observational study.

Free fatty acids (FFA) are a known risk factor in the development of sudden cardiac death. However, the relationship between FFA and the outcome of out-of-hospital cardiac arrest (OHCA) patients remains unclear. We aimed to examine the association between FFA and neurological outcomes in OHCA patients. This prospective observational study included adult (≥18 years) OHCA patients between February 2016 and December 2022. We measured serial FFA levels within 1 hour after ROSC and at 6, 12, 24, 48, and 72 hours after the return of spontaneous circulation (ROSC). The primary outcome was neurological outcome at 6 months. A poor neurological outcome was defined by cerebral performance categories 3, 4, and 5. A total of 147 patients were included. Of them, 104 (70.7%) had poor neurological outcomes, whereby the median FFA levels within 1 hour after ROSC (0.72 vs 1.01 mol/L), at 6 hours (1.19 vs 1.90 mol/L), 12 hours (1.20 vs 1.66 mol/L), and 24 hours (1.20 vs 1.95 mol/L) after ROSC were significantly lower than in good outcome group. The FFA levels at 6 hours (odds ratio, 0.583; 95% confidence interval, 0.370-0.919; P = .020), and 12 hours (odds ratio, 0.509; 95% confidence interval, 0.303-0.854; P = .011) after ROSC were independently associated with poor neurological outcomes. The lower FFA levels at 6 hours and 12 hours after ROSC were associated with poor neurological outcomes in patients with OHCA. FFA may reflect oxidative metabolism as well as oxidative stress.

Effects of packaging method and temperature on the quality and lipid degradation of snakehead fish (Channa striata) fillets during frozen storage

Temperature and packaging method are considered the main factors affecting the quality of fishery products during frozen storage. In the present study, snakehead fish fillets were air (AP) and vacuum (VP) packaged and stored at -20±2°C and -25±2°C for six months to investigate the effects of temperature and packaging method on the quality of snakehead fish fillets. Changes in the quality of snakehead fish fillets were assessed by determinations of lipid hydrolysis, lipid oxidation, and their resulting changes in colour, cooking yield (CY), and total volatile basic nitrogen (TVB-N) content. Storage temperature and packaging method showed strong preservative effects on the quality of snakehead fish fillets. Higher cooking yield and lower TVB-N content were observed in the VP samples stored at -25±2°C compared to the AP samples and stored at -20±2°C. Vacuum packaging and lower storage temperature (i.e. -25±2°C) significantly retarded lipid hydrolysis and lipid oxidation development. This resulted in lower free fatty acid (FFA), lipid hydroperoxides (PV), thiobarbituric acid-reactive substances (TBARS) values, and higher phospholipid content. Significant correlations between lipid oxidation products (PV and TBARS) and yellow discolouration (b* values) were found in this study. Based on these findings, it could be suggested that frozen snakehead fish fillets should be vacuum-packaged and stored at low temperatures to maintain their quality.

Lipid Quality Assessment of Virgin Coconut Oil Produced with Different Blanching Methods

Virgin Coconut Oil (VCO) is prone to oxidation due to the natural enzymes present in the coconut. Blanching has been studied to inactivate lipase and peroxidase enzymes that create deterioration in the product. Adding citric acid in hot water during blanching resulted in a higher quality product due to complexing agent properties to chelate metal substances and lowering the pH to reduce the enzymatic activities of the products. This research aims to analyze the effect of different blanching methods on VCO's lipid quality, antioxidant properties, and total phenolic content. Fresh coconut was subjected to water blanching at 95ºC for 5 minutes and 80ºC for 10 minutes with and without 0.05% citric acid addition. After that, VCO was produced using the chilling thawing method, which combines centrifugation and low-temperature incubation. VCO was analyzed in the free fatty acid (FFA), iodine value (IV), peroxide value (PV), TBARS value, the antioxidant activities by ABTS and DPPH, and total phenolic content (TPC). The results showed that water blanching with 0.05% citric acid at 80ºC for 10 minutes obtained better lipid quality compared to control with high IV (6.612±0.085 g iodine/g sample), low FFA (0.0241±0.0023 mg KOH/g sample), and low TBARS value (2.76±0.23 mg MDA/g sample). However, there is a contrary result between antioxidant activities and TPC that might reveal exciting findings. Despite a decrease in the antioxidant activities (DPPH: 39.93±3.11%RSA, ABTS: 9.80±0.91%RSA), the TPC value was increased (9.16±1.56 mg GAE/g sample). Therefore, hot water blanching with 0.05% citric acid addition can be conducted as a pre-treatment in the production of VCO to maintain the lipid quality, even though there is a contradiction in the TPC and antioxidant results.

Albumin is an important factor in the control of serum free fatty acid flux in both male and female mice.

Albumin knockout (Alb-/-) mice exhibit a low plasma free fatty acid (FFA) concentration, but it was not known if the suppressed concentration reflects a lower rate of appearance (Ra) of FFA in the circulation (i.e., lower FFA flux) or if the absence of albumin alters the relationship between FFA flux and concentration. For understanding the role of albumin in FFA transport through the bloodstream, it is not sufficient to rely on FFA concentration data alone. Therefore, we developed a method to study FFA kinetics in Alb-/- mice. Using an albumin-free formulation of [U-13C]palmitate tracer, serum FFA kinetics were tested in Alb-/- and wild-type (WT) mice. Results indicate that the flux of FFA in serum of Alb-/- mice was significantly lower than in WT mice (P < 0.05), while albumin deficiency did not alter the relationship between FFA flux and concentration. Next, to test if suppressed lipolysis might have also been involved in the suppressed FFA kinetics, gene expression of a lipolytic enzyme (adipose triglyceride lipase, Atgl) and a marker of lipolysis (phosphorylation of hormone-sensitive lipase, p-HSL) were measured in adipose tissue. In contrast to the low FFA flux in Alb-/-, both Atgl gene expression and p-HSL protein were significantly higher in adipose tissue of Alb-/- than in WT mice (P < 0.05). Thus, the low FFA flux in Alb-/- appeared to be driven by the absence of albumin's FFA binding functions rather than through regulation of lipolysis, indicating that albumin is an important factor in determining the flux of FFA in circulation.NEW & NOTEWORTHY To improve understanding of the albumin protein's function in vivo, we tested plasma free fatty acid kinetics in albumin knockout mice compared with wild-type mice. Using a new tracer formulation strategy, it was discovered that the appearance rate of free fatty acids in serum is lower in albumin knockout mice than in wild-type mice. The results indicate that albumin is a major controller of free fatty acid kinetics.

Metabolic characteristics of transmembrane prolyl 4-hydroxylase (P4H-TM) deficient mice

Transmembrane prolyl 4-hydroxylase (P4H-TM) is an enigmatic enzyme whose cellular function and primary substrate remain to be identified. Its loss-of-function mutations cause a severe neurological HIDEA syndrome with hypotonia, intellectual disability, dysautonomia and hypoventilation. Previously, P4H-TM deficiency in mice was associated with reduced atherogenesis and lower serum triglyceride levels. Here, we characterized the glucose and lipid metabolism of P4h-tm−/− mice in physiological and tissue analyses. P4h-tm−/− mice showed variations in 24-h oscillations of energy expenditure, VO2 and VCO2 and locomotor activity compared to wild-type (WT) mice. Their rearing activity was reduced, and they showed significant muscle weakness and compromised coordination. Sedated P4h-tm−/− mice had better glucose tolerance, lower fasting insulin levels, higher fasting lactate levels and lower fasting free fatty acid levels compared to WT. These alterations were not present in conscious P4h-tm−/− mice. Fasted P4h-tm−/− mice presented with faster hepatic glycogenolysis. The respiratory rate of conscious P4h-tm−/− mice was significantly lower compared to the WT, the decrease being further exacerbated by sedation and associated with acidosis and a reduced ventilatory response to both hypoxia and hypercapnia. P4H-TM deficiency in mice is associated with alterations in whole-body energy metabolism, day-night rhythm of activity, glucose homeostasis and neuromuscular and respiratory functions. Although the underlying mechanism(s) are not yet fully understood, the phenotype appears to have neurological origins, controlled by brain and central nervous system circuits. The phenotype of P4h-tm−/− mice recapitulates some of the symptoms of HIDEA patients, making this mouse model a valuable tool to study and develop tailored therapies.

Adsorption study of isotherms, kinetics modelling, and thermodynamics of immobilized Candida rugosa lipase on metal oxide for esterification of waste cooking oil

The problem regarding improper disposal of waste cooking oil (WCO) can be solved via biotransformation of WCO to value added product using lipases as a biocatalyst. Thus, immobilization method was proposed for the recyclability of the biocatalyst. However, a comprehensive discussion on adsorption study is limited for lipase immobilization. In this study, Candida rugosa lipase (CRL) was immobilized on modified metal oxide (Mg2+/Al2O3) and the support was improved by addition of activating agent (L-lysine/Mg2+/Al2O3). Subsequently, the biocatalysts were used for esterification of WCO in the presence of methanol. Maximum adsorption capacity for the support was improved after addition of L-lysine resulting in 0.262 mg protein/g of support. The equilibrium adsorption data for both systems were fitted to the Redlich Peterson isotherm model while the kinetics study was most fitted with Elovich model, and the adsorption process were influenced by intraparticle and film diffusion mechanisms. Thermodynamic analysis explained that the adsorption process of CRL/L-lysine/Mg2+/Al2O3 was more spontaneous and stronger as compared to CRL/Mg2+/Al2O3. Furthermore, CRL/L-Lysine/Mg2+/Al2O3 exhibited its potential in esterification of WCO by converting 62.95% of free fatty acid (FFA), while CRL/Mg2+/Al2O3 converted lower FFA (53.62%). This study offers a fundamental understanding on designing an effective immobilization system by addition of activating agent to develop a good biocatalyst for biotransformation of WCO.

Very-low-density lipoprotein triglyceride and free fatty acid plasma kinetics in women with high or low brown adipose tissue volume and overweight/obesity

Although a high amount of brown adipose tissue (BAT) is associated with low plasma triglyceride concentration, the mechanism responsible for this relationship in people is not clear. Here, we evaluate the interrelationships among BAT, very-low-density lipoprotein triglyceride (VLDL-TG), and free fatty acid (FFA) plasma kinetics during thermoneutrality in women with overweight/obesity who had a low (<20mL) or high (≥20mL) volume of cold-activated BAT (assessed by using positron emission tomography in conjunction with 2-deoxy-2-[18F]-fluoro-glucose). We find that plasma TG and FFA concentrations are lower and VLDL-TG and FFA plasma clearance rates are faster in women with high BAT than low BAT volume, whereas VLDL-TG and FFA appearance rates in plasma are not different between the two groups. These findings demonstrate that women with high BAT volume have lower plasma TG and FFA concentrations than women with low BAT volumes because of increased VLDL-TG and FFA clearance rates. This study was registered at ClinicalTrials.gov (NCT02786251).

Comparative study of virgin olive oil from Moroccan Picholine cultivars in TADLA perimeter -Morocco

Olive oil, extracted from olive fruits (Olea europaea), is renowned for its distinctive flavour, nutritional richness and health benefits. The aim of this comparative study is to analyze olive oil from several TADLA perimeter units, including Province of AZILAL, FQUIH BEN SALAH, BENI MELLAL, ZAOUIT CHEIKH, and BRADIA. The oil under investigation was extracted from olives of the Moroccan Picholine variety, by a discontinuous system including grinding, pressing and decanting. Significant variations were found at the values of the studied parameters. The results of our study showed that Olive oil from FBS and BM are classified as an extra virgin olive. However, olive oils from ZC, BR and AZ are classified as virgin olive oil. Sample from FQUIH BEN SALAH province had the lowest Free Fatty Acids (FFA) and peroxide values 0.236% oleic acid and 3.434 méqO2/Kg respectively. While the highest FFA value found was the olive oil obtained from AZILAL (1.084% Oléic Acid) and the highest Peroxide value was obtained in the sample from BRADIA (8.108 méq O2/Kg). E232, E270 and delta K values of all samples were under the limit fixed by IOC for virgin olive oil. Polyphenols content of ZAOUIT CHEIKH, FQUIH BEN SALAH and BRADIA oils are relatively high with values equal to 1.347, 1.082, and 1.141mg GA/100ml extract respectively. DPPH test showed that ZAOUIT CHEIKH oil had the greater antioxidant capacity.

Garcinia Biflavonoid 1 from Garcinia kola Ameliorates Glycolipid Metabolism Disorder in Type 2 Diabetic db/db Mice

Background: Garcinia kola is recommended in African folk medicine for the treatment of diabetes and its associated complications. In this study, we investigated the effects of Garcinia biflavonoid 1 (GB1), an active chemical component of Garcinia kola, on blood glucose and lipid in db/db mice with type 2 diabetes. Methods: Db/db mice were divided into 4 groups: vehicle, low-dose GB1 (50 mg/kg), high-dose GB1 (100 mg/kg), and rosiglitazone, and treated for 4 weeks. Body weight, fasting blood glucose (FBG), fasting insulin, oral glucose tolerance test (OGTT), insulin tolerance test (ITT), hepatic glycogen, serum and liver biochemical parameters, and histological morphology of the pancreas, heart, and kidneys were evaluated. Results: GB1 significantly reduced FBG, the area under the curve value of OGTT and ITT, and the homeostasis model assessment of insulin resistance, increased the homeostasis model assessment of β-cell function, quantitative insulin sensitivity check index, and the level of hepatic glycogen. Lower triglyceride and free fatty acid level, and a lower triglyceride-glucose index were also observed in the GB1 groups. In addition, no significant changes in alanine aminotransferase and aspartate aminotransferase levels, or in the histopathology of the pancreas, heart, or kidney were observed after GB1 treatment. Conclusion: These findings indicate that GB1 exerts an antidiabetic effect in db/db mice, by improving hyperglycemia, insulin resistance, and lipid dysregulation without evidence of adverse reactions.