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Opuntia dillenii Ker Gawl. is one of the medicinal plants used for the prevention and treatment of diabetes mellitus (DM) in Morocco. This study aims to investigate the antihyperglycemic effect of Opuntia dillenii seed oil (ODSO), its mechanism of action, and any hypoglycemic risk and toxic effects. The antihyperglycemic effect was assessed using the OGTT test in normal and streptozotocin (STZ)-diabetic rats. The mechanisms of action were explored by studying the effect of ODSO on the intestinal absorption of d-glucose using the intestinal in situ single-pass perfusion technique. An Ussing chamber was used to explore the effects of ODSO on intestinal sodium-glucose cotransporter 1 (SGLT1). Additionally, ODSO’s effect on carbohydrate degrading enzymes, pancreatic α-amylase, and intestinal α-glucosidase was evaluated in vitro and in vivo using STZ-diabetic rats. The acute toxicity test on mice was performed, along with a single-dose hypoglycemic effect test. The results showed that ODSO significantly attenuated the postprandial hyperglycemia in normal and STZ-diabetic rats. Indeed, ODSO significantly decreased the intestinal d-glucose absorption in situ. The ex vivo test (Ussing chamber) showed that the ODSO significantly blocks the SGLT1 (IC50 = 60.24 µg/mL). Moreover, ODSO indu\ced a significant inhibition of intestinal α-glucosidase (IC50 = 278 ± 0.01 µg/mL) and pancreatic α-amylase (IC50 = 0.81 ± 0.09 mg/mL) in vitro. A significant decrease of postprandial hyperglycemia was observed in sucrose/starch-loaded normal and STZ-diabetic ODSO-treated rats. On the other hand, ODSO had no risk of hypoglycemia on the basal glucose levels in normal rats. Therefore, no toxic effect was observed in ODSO-treated mice up to 7 mL/kg. The results of this study suggest that ODSO could be suitable as an antidiabetic functional food.

Lavandula pedunculata (Mill.) Cav. (LP) is one of lavender species traditionally used in Morocco to prevent or cure diabetes, alone or in the form of polyherbal preparations (PHP). Therefore, the primary objective of this study was to test the antihyperglycemic effect of the aqueous extract of LP, alone and in combination with Punica granatum L. (PG) and Trigonella foenum-graecum L. (FGK). The secondary objective was to explore some mechanisms of action on the digestive functions. The antihyperglycemic effect of the aqueous extract of LP, alone and in combination with PG and FGK, was studied in vivo using an oral glucose tolerance test (OGTT). In addition, LP extract was tested on the activities of some digestive enzymes (pancreatic α-amylase and intestinal α-glucosidase) in vitro and on the intestinal absorption of glucose ex vivo using a short-circuit current (Isc) technique. Acute and chronic oral administration of LP aqueous extract reduced the peak of the glucose concentration (30 min, p < 0.01) and the area under the curve (AUC, p < 0.01). The effect of LP + PG was at the same amplitude to that of the positive control Metformin (MET). LP aqueous extract inhibited the pancreatic α-amylase with an IC50 almost identical to acarbose (0.44 ± 0.05 mg/mL and 0.36 ± 0.02 mg/mL, respectively), as well as the intestinal α-glucosidase, (IC50 = 131 ± 20 µg/mL) and the intestinal glucose absorption (IC50 = 81.28 ± 4.01 µg/mL) in concentration-dependent manners. LP aqueous extract exhibited potent actions on hyperglycemia, with an inhibition on digestive enzymes and glucose absorption. In addition, the combination with PG and FGK enhanced oral glucose tolerance in rats. These findings back up the traditional use of LP in type 2 diabetes treatment and the effectiveness of the alternative and combinative poly-phytotherapy (ACPP).

Lavender aqueous extracts are widely used in the Moroccan traditional medicine for their antibacterial properties. However, previous research have generally focused on investigating the antibacterial activity of lavender essential oils. The aim of this study is to evaluate the antibacterial activity of the Moroccan Lavandula pedunculata (Mill.) Cav. aqueous extract, alone, as well as in combination with extracts of other plant species known for their antibacterial activity: Salvia rosmarinus Spenn., Salvia lavandulifolia Vahl. and Origanum compactum Benth. We have tested the antibacterial activity of L. pedunculata, S. rosmarinus, S. lavandulifolia and O. compactum aqueous extracts individually and in combination against 34 strains using the agar dilution method. The combination effect was evaluated using the fractional inhibitory concentration (FIC). Polyphenol and tannin contents were determined using Folin-Ciocalteu reagent, and then some phenolic compounds were identified using UHPLC-MS. All the extracts displayed a large spectrum of antibacterial activity, especially against staphylococci, streptococci, Mycobacterium smegmatis and Proteus mirabilis. The minimum inhibitory concentration (MIC) values reached 0.15 ± 0.00 mg/mL for Staphylococcus warneri tested with S. lavandulifolia and 0.20 ± 0.07 mg/mL for Staphylococcus epidermidis tested with L. pedunculata or S. rosmarinus. Association of the L. pedunculata extract with S. rosmarinus, S. lavandulifolia and O. compactum showed synergistic effects (FIC ≤ 1). Moreover, the association of L. pedunculata with S. lavandulifolia was active against most of the Gram-negative strains resistant to the individual extracts. Determination of polyphenol and tannin contents showed the richness of the studied plants in these compounds. Additionally, chromatographic analysis demonstrated the high presence of rosmarinic acid in all the studied plant extracts. To our knowledge, this is the first study that shows the enhancing effect of the antibacterial activity of L. pedunculata aqueous extract combined with S. rosmarinus, S. lavandulifolia and O. compactum. These results confirm the effectiveness of the plant mixtures commonly used by traditional healers in Morocco and suggest that L. pedunculata might be used as an antibacterial agent either alone or, more efficiently, in combination with S. rosmarinus, S. lavandulifolia and O. compactum.

Ziziphus lotus (L.) Lam. (Z. lotus) is a medicinal plant species that is widely distributed throughout the Mediterranean basin. Moroccans traditionally use it to treat many illnesses thanks to its beneficial medicinal properties. The purpose of this study is to assess the anti-hyperlipidemic and antioxidant activities of a flavonoid-rich aqueous extract of Z. lotus fruits (ZLF). The 2-2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assay and the β-carotene bleaching test were used to determine the antioxidant activity of ZLF. The anti-hyperlipidemic effect of the aqueous extract of ZLF (200 and 400 mg/kg) was evaluated in albino mice exposed to the chronic high-fat diet, based on lipid profile, blood sugar, and changes in growth performance. The results showed that the aqueous extract of ZLF rich in flavonoids (2242.89 ± 25 µg QE (quercitin equivalent)/mg), and has a considerable antioxidant power against DPPH radicals (IC50 = 116 ± 0.02 µg/mL) and β-carotene oxidation. The aqueous extract of ZLF also showed a significant anti-hyperlipidemic effect by improving abnormal changes in lipid profile and blood glucose levels in albino mice exposed to a chronic high-fat diet. Our findings suggest that the anti-hyperlipidemic activities of ZLF aqueous extract are correlated with its flavonoid content and antioxidant activity. Therefore, the aqueous extract of ZLF could be an essential therapeutic candidate for hyperlipidemia patients, thanks to its richness in bioactive molecules.

We undertook this ethnobotanical study for identifying and valorising medicinal plants exploited as food additives, and to establish a database of aromatic and medicinal plants used as food additives in traditional phytotherapy in Morocco (Fez-Meknes,

Pistacia atlantica Desf. is a widely used plant species in the traditional medicine for its various pharmacological properties. The aim of this study is the valorisation of polyphenols and the antioxidant power of three organs from Pistacia atlantica Desf. (leaves, fruits, and bark). Phytochemical screening of secondary metabolites was performed using precipitation and coloring reactions. Total phenols, flavonoids, and condensed tannins were quantified, respectively, by the Folin-Ciocalteu method, the aluminum trichloride method, and the vanillin method. Evaluation of the antioxidant activity was made using two methods: DPPH ∗ (2,2 ′ -diphenyl-1-picryl hydrazyl) and FRAP (ferric reducing antioxidant power). The obtained results showed that the three organs of Pistacia atlantica are rich in total phenols, flavonoids, and condensed tannins. The highest contents of total phenols and flavonoids are recorded by the crude fruit extract, 723 mg EGA/gE and 34.57 mg EQ/gE, respectively, while the highest content of condensed tannins is recorded in the butanolic extract of the leaves (997.58 mg ECat/gE). The antioxidant activity of the three organs extracts from Pistacia atlantica Desf. confirmed their strong antiradical power, much higher than that of ascorbic acid and BHA (butylated hydroxyanisole). Indeed, the concentration of the crude extract of P. atlantica leaves reducing 50% of the DPPH ∗ free radicals (IC50) is 27.22 μg/ml. This concentration is much lower than those of ascorbic acid (31.44 μg/ml) and BHA (46.25 μg/ml). The antioxidant power using the FRAP method has also shown that the leaves extract of this species has a much higher reducing capacity of iron than those of the reference standards. A positive correlation between antioxidant capacities and flavonoids contents of leaves and fruits extracts was observed. The two methods (DPPH ∗ and FRAP) proved that the three organ extracts of Pistacia atlantica possess very remarkable antioxydant activity. These extracts could be exploited as natural antioxidants against the oxidation phenomenons and the oxidative stress in several fields (food, cosmetic, pharmaceutic, and others).

Summary Opuntia species belong to semi-arid and arid regions of Mexico and the United States. O. ficus-indica and O. dillenii are commonly used in alternative medicine to treat various diseases. Up to date, several scientific works have been carried out on the different parts of these plants. However, over the last few years, studies have been focusing on the oil obtained from the fruit seeds of these species. For this reason, this study aims to draw the attention of researchers toward the phytochemical and the pharmacological effects of these two Opuntia oils, which would help set up other scientific projects that promote these products. Phytochemical studies have shown that these oils are rich in biologically active molecules, such as unsaturated fatty acids and phytosterols (mainly linoleic acid and β-sitosterol), as well as vitamin E, which is represented only by the γ-tocopherol. Besides, these oils are rich in polyphenols that protect them from photo-oxidation. Moreover, several studies have shown their antioxidant, anti-diabetic, antibacterial, antifungal, anti-inflammatory, hepatoprotective, and gastroprotective activities, as well as their hypolipidemic properties. The beneficial effects of these oils include also their ability to block the weight loss, and what makes them more interesting is their safety, according to the literature.