Antidiabetic, antihyperlipidemic and antioxidant influences of the spice cinnamon (Cinnamomum zeylanicumon) in experimental rats

The present study investigates the effect of cinnamon (Cinnamomum zeylanicumon) powder supplementation on glucose levels, lipid profiles, and oxidative stress parameters in alloxan-induced diabetic rats. Diabetes was induced in adult male Wistar rats via a single subcutaneous alloxan injection (15 mg/kg). Cinnamon powder was mixed with the standard feed of the rats in an amount of 5% for 28 consecutive days. Serum concentrations of total cholesterol (TC) and triglycerides (TG) were assayed at the end of the experimental period in all investigated groups. Anti-oxidative enzymes such as glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD) were sought in the serum and pancreas. Alloxan caused the fasting blood sugar level to increase. The administration of cinnamon blocked the increase of blood glucose. There was also a significant difference in the TG and TC levels between control and treated diabetic rats. In diabetic rats, cinnamon treatment restored the activities of SOD, CAT and GPx. These findings suggested that cinnamon has an anti-hyperglycemic effect, improves lipid profiles, and protect against damage induced by oxidative stress in the diabetic state

Phenolic Compounds and Skin Permeability: An In Silico Investigation

Background: The skin is the largest organ of the body and provides the main barrier between the internal and external environment. Assessment of skin permeability is of critical importance for understanding and predicting in vivo efficacy and bioavailability of bioactive phenolic compounds. Objectives: This study investigated the relationship between skin permeability and phenolic compounds using in silico methods. Methods: Screening of skin permeability was performed on 475 randomly selected phenolic compounds. Molecules were expressed in SMILE format downloaded from Phenol-Explorer Database (version 3.6, 2016). Then, their skin permeability was determined by the linear model of the quantitative structure-activity relationship (QSAR). The obtained results were investigated for normal distribution and correlation with pharmacological properties. Results: Our investigation showed that ferulate hydroxycinnamic acid derivatives were the most important phenolic subclass with a permeability of -1.65 cm/s. The relationship between permeability and lipophilicity, water solubility, synthetic accessibility, and bioavailability was evaluated. The statistical analysis revealed that the highest skin permeability was associated with three parameters: the topological polar surface area (TPSA), molecular weight, and lipophilicity (iLog P). Conclusion: The cutaneous permeability depended on several chemical parameters of the molecule used. The classification of phenolic compounds according to their structures proved a wide variability in this permeability

Variations in composition and antioxidant activity of Tunisian Pistacia lentiscusL. leaf essential oil

In this study, the composition and antioxidant activity of Pistacia lentiscus L. leaf essential oil (EO) from four Tunisian localities were investigated. The EO yields (%, w/w) of P. lentiscus leaf were 0.009% in Oued El Bir, 0.02% in Jebel Mansour, 0.007% in Siliana and 0.01% in Tabarka. The main compounds of Oued El Bir EO were terpinene-4-ol (41.24%) and α-terpineol (7.31%), whereas those of Jebel Mansour were α-pinene (9.48%), limonene (19.11%) and α-phellandrene (3.20%). In Siliana samples, terpinene-4-ol (23.32%), β-caryophyllene (22.62%) and α-terpineol (7.12%) were the main compounds. For P. lentiscus L. from Tabarka, α-terpineol (9.79%) and β-caryophyllene (38.33%) were the major constituents. Three chemotypes of P. lentiscus EO were identified for the first time in Tunisia. P. lentiscus EOs were also screened for their antioxidant activities. The 1,1-diphenyl-2-picrylhydrazyl assay gives an IC50 range value of 60–110 μg/mL for all the samples studied. EOs from different Tunisian localities showed lower β-carotene bleaching activity than butylated hydroxytoluene and butylated hydroxyanisol. P. lentiscus EO presents a very low capacity to chelate ferrous irons (IC50 = 80.8–104 μg/mL) and no metal chelating activity was recorded

Synergistic Effect of Cloves (Syzygium aromaticum), Thyme (Thymus vulgaris) and Lemon (Citrus limon) Blended Essential Oils Optimized by Mixture Design for Improving the Antioxidant Activity

Background: Combining various essential oils (EOs) for developing pharmaceutical formulations has been the focus of attention in recent years. Objectives: This study aimed to determine the antioxidant effect of the combination of three Eos obtained from clove (Syzygium aromaticum L.), lemon peel (Citrus limon L.), and thyme (Thymus vulgaris L.) by using mixture design. Methods: The EOs of lemon peel (EOL), clove (EOC), and thyme (EOT) as well as their combination were analyzed using a gas chromatograph with flame ionization detector (GC/FID). The antioxidant activities of the EOs from EOL, EOC, and EOT as well as their combination were measured adopting DPPH assay. The construction and statistical analysis of the experiment were designed using the NemrodW (LPRAI, version 2000) software. Results: EOL, EOC, and EOT were found capable of neutralizing DPPH radical. EOC was distinguished by its strongest antiradical activity with IC50=15.02±0.02 µg/mL. EOT had an IC50=29.20±0.12 µg/mL while EOL had 188.69±0.95 µg/mL. The positive standard BHT was detected to be IC50=24±0.02 µg/ mL. The optimal, combinative mixture of essential oils may have been determined based on these isoresponse curves which allowed fixing the ideal combinations of ingredient in terms of quantity to obtain an EO mixture possessing appreciable and optimal antioxidant characteristics. The predicted antioxidant properties determined by the mixing plan model were retained and the experiments were carried out respecting the contents of proposed ingredients of 25.7% EOT, 32.3% EOL, and 41.9% EOC equivalent to 15.42 mg, 19.38 mg and 25.14 mg, respectively. This resulted in arriving at an essential oil mixture with an experimental IC50=11.023±0.145 µg/mL which was similar to those of the predicted antioxidant properties with an order of 10.907±0.212 µg/mL and a non-significant difference of P<0.05, based on which the validity of the proposed mixing plan model was determined. The combined EO was also found to be rich in eugenol (32.35±1.13%), thymol (25.49±0.03%), and limonene (21.30±0.02%). Conclusion: Statistical planning and the development of utility profiles for mixtures of essential oils may have been used to predict the optimal composition as well as to determine their antioxidant profile

Green Extraction of Fennel and Anise Edible Oils Using Bio-based Solvent and Supercritical Fluid: Assessment of Chemical Composition, Antioxidant Property and Oxidative Stability

The aim of this study was to evaluate the replacement aspects of conventional methods (petroleum-based solvent and Folch assay) by alternative methods (bio-based and biodegradable solvent 2-methyltetrahydrofuran (MeTHF) and supercritical CO2 (SC-CO2)) for seed oil extraction from anise (Pimpinella anisum L.) and fennel (Foeniculum vulgare Mill.). Results showed that the highest oil yield of aniseeds was obtained by using Folch (24.07%) and MeTHF (23.65%) extraction methods whereas fennel seeds had 20.02% and 18.72%, respectively. Fatty acid composition of both seed oils obtained by the two green extraction methods was similar to the conventional ones with the predominance of petroselinic acid (54.22–61.25% in fennel and 42.39– 48.97% in anise). Besides, SC-CO2 method allowed to obtain the maximum of sterol content in anise (3.85 mg/g of oil) and fennel (4.64 mg/g of oil) seed oils. Furthermore, anise and fennel seed oils extracted with MeTHF method significantly showed higher total phenolic content (2.43 and 1.32 mg GA/g oil, respectively), stronger antioxidant activity (9.23 and 5.04 μmol TEAC/g oil, respectively), and oxidative stability (8.23 and 10.15 h, respectively) than the other methods (p < 0.05). In conclusion, MeTHF appeared to be a good substitute to petroleum solvents for recovery of high oil quality from Pimpinella anisum and Foeniculum vulgare seeds.MESRS LR15CBBC0

A comparative assessment of antifungal activity of essential oils of five medicinal plants from Tunisia

The leaf essential oil yields of clementine, cypress, rosemary, tea, and thyme were 0.22, 0.87, 1.46, 1.20, and 0.72%, respectively, based on the dry weight of the plant material. The leaf essential oils of rosemary, tea, and thyme contained the highest levels of oxygenated monoterpenes (60.14-91.70%). Rosemary and tea leaf essential oils were rich in 1,8-cineole (49.98% and 57.55%, respectively), and they have potent antifungal activity against Alternaria alternata strain (MIC = 5000 μg/ml). Thyme was rich in carvacrol (78.54%) and had a MIC of 6000 μg/ml against A. alternata strain. Clementine leaf essential oil was characterized by the predominance of monoterpene hydrocarbons (88.65%), and it possessed a weak antifungal activity against A. alternata (MIC = 8000 μg/ml). Cypress leaf essential oil was characterized by the predominance of oxygenated sesquiterpenes (60.67%), having an antifungal activity of 8000 μg/ml

Research progress of Tunisian medicinal plants used for acute diabetes

The use of the medicinal plants in treating diabetes is frequent in Africa, especially in Tunisia, and it is ritually transmitted from generation to generation within cultures. Many of Tunisian medicinal plants have been experimentally validated. A comprehensive review was conducted to pile up information from scientific journal articles, including indigenous knowledge researches, about Tunisian medicinal plants used for the treatment of diabetes. The aim of this review article is to provide the reader with information concerning the importance of Tunisian medicinal plants in the treatment of diabetes and to draw attention of the health professionals and scientists working in the field of pharmacology and therapeutics to develop new drug formulations to cure different kinds of diabetes

Antidiabetic, antihyperlipidemic and antioxidant influences of the spice cinnamon ( Cinnamomum zeylanicumon ) in experimental rats

ABSTRACT The present study investigates the effect of cinnamon (Cinnamomum zeylanicumon) powder supplementation on glucose levels, lipid profiles, and oxidative stress parameters in alloxan-induced diabetic rats. Diabetes was induced in adult male Wistar rats via a single subcutaneous alloxan injection (15 mg/kg). Cinnamon powder was mixed with the standard feed of the rats in an amount of 5% for 28 consecutive days. Serum concentrations of total cholesterol (TC) and triglycerides (TG) were assayed at the end of the experimental period in all investigated groups. Anti-oxidative enzymes such as glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD) were sought in the serum and pancreas. Alloxan caused the fasting blood sugar level to increase. The administration of cinnamon blocked the increase of blood glucose. There was also a significant difference in the TG and TC levels between control and treated diabetic rats. In diabetic rats, cinnamon treatment restored the activities of SOD, CAT and GPx. These findings suggested that cinnamon has an anti-hyperglycemic effect, improves lipid profiles, and protect against damage induced by oxidative stress in the diabetic state