Mineral Content, Chemical Analysis, In Vitro Antidiabetic and Antioxidant Activities, and Antibacterial Power of Aqueous and Organic Extracts of Moroccan Leopoldia comosa (L.) Parl. Bulbs.

Medicinal plants are a rich source of bioactive phytochemicals or bionutrients. Studies carried out during the past few decades have shown that these phytochemicals play an important role in preventing metabolic diseases such as cancer and diabetes. The present study was dedicated to the analysis of mineral and chemical composition and evaluation of antidiabetic, antioxidant, and antibacterial properties of aqueous and organic extracts of Leopoldia comosa, a plant with a long history of therapeutic and food use. Mineral content was determined using inductively coupled plasma atomic emission spectroscopy. Chemical composition was carried out by extraction of essential oils, preparation of aqueous and organic extracts, and qualitative and quantitative analysis. The biological study consisted of the evaluation of antidiabetic activity by inhibition of three enzymes, antioxidant activity by five tests, and antibacterial activity by the disc diffusion method. The correlation between chemical composition and antidiabetic and antioxidant properties was explored by PCA. The results showed that L. comosa contains high levels of Fe, K, P, Na, Cu, Mg, and Ca with values, respectively, in the order of 33552, 1843.14, 756.36, 439.65, 303.9, 272.37, and 20.55 mg/kg. Quantitative analysis showed that the diethyl ether extract had the highest content of polyphenols (129.75 ± 0.29 µg GAE/mg E), flavonoids (988.26 ± 0.18 µg QE/mg E), and tannins (30.22 ± 0.15 µg CE/mg E). All extracts of L. comosa possess inhibitory activity of alpha-amylase, alpha-glucosidase, and beta-galactosidase enzymes, mainly the decocted and the acetone extract. The antioxidant results showed that organic extracts are more active than aqueous extracts especially diethyl ether extract which was similarly found to have an antibacterial effect on Listeria innocua and Proteus mirabilis. PCA allowed us to deduce that phenolic compounds, flavonoids, and tannins are strongly correlated with antioxidant and antidiabetic activity. L. comosa may have potential remedy in the prevention of metabolic disease.

Mineral Composition, Phenolic Content, and In Vitro Antidiabetic and Antioxidant Properties of Aqueous and Organic Extracts of Haloxylon scoparium Aerial Parts.

Haloxylon scoparium is a plant widely used in traditional medicine for the treatment of diabetes. Hence, this study focuses on the mineralogical and chemical composition and evaluation of the antidiabetic and antioxidant activities of the aerial part of this species. The mineralogical analysis was done by inductively coupled plasma atomic emission spectrometry (ICP-AES). The phytochemical study consisted in the preparation of different extracts from the aerial part by aqueous and organic extraction using Soxhlet and cold maceration. Then, phytochemical screening was performed on the plant powder and on the extracts, which is completed by spectrophotometric quantification of total polyphenols, flavonoids, and catechic tannins. The evaluation of antidiabetic activity was done by three enzymes: a-amylase, a-glucosidase, and ß-galactosidase, and that of antioxidant activity was done by five methods: H2O2, DPPH, ABTS, FRAP, and reducing power (RP). Mineralogical analysis revealed the presence of iron, potassium, magnesium, phosphorus, sodium, copper, calcium, strontium, selenium, and zinc. The studied part is rich in alkaloids, flavonoids, catechic tannins, and saponins. The methanolic extract is rich in total polyphenols (161.65 ± 1.52 Ug EAG/mg E), and the ethyl acetate extract has high levels of catechic tannins (23.69 ± 0.6 Ug EC/mg E). In addition, the decoctate expresses a high flavonoid content of 306.59 ± 4.35 Ug EQ/mg E. The in vitro evaluation of the antidiabetic activity showed that the decoctate has a higher inhibitory capacity on a-glucosidase (IC50 = 181.7 ± 21.15 ug/mL) than acarbose (IC50 = 195 ± 6.12 ug/mL). The results of the antioxidant activity showed that the methanolic extract and the decoctate present a percentage of hydrogen peroxide (H2O2) scavenging (20.91 ± 0.27 and 16.21 ± 0.39%) higher than that of ascorbic acid (14.35 ± 0.002%). Positive correlations obtained between the total polyphenol content and the antioxidant activity of the extracts were studied. A positive correlation of a-amylase inhibitory activity was also recorded with the antioxidant activity tests.

Phytochemical investigation, in vitro and in vivo antioxidant properties of aqueous and organic extracts of toxic plant: Atractylis gummifera L.

ETHNOPHARMACOLOGICAL RELEVANCE: Atractylis gummifera is a toxic plant widely used in Mediterranean traditional medicine against colds, dizziness, and headaches, as an antisyphilitic, against boils, as a purgative, emetic and deworming. All studies reported on this plant have been carried out either on the plant and its traditional uses, or on cases of poisoning by this plant. However, few pharmacological studies have readjusted the traditional uses of this plant. AIM OF THE STUDY: The purpose of this article is to carry out a preliminary phytochemical study of Atractylis gummifera and to evaluate in vitro and in vivo antioxidant activity of its aqueous and organic extracts and to provide a complementary analysis of the mechanisms of action of the different antioxidant activity tests studied. METHODS: The phytochemical study consisted of the hot and cold preparation of aqueous extracts: (decocted, infused, macerated), organic extracts: (methanolic, methanolic macerated, chloroformic, ethyl acetate, petroleum ether) and the determination of the secondary metabolites of these extracts. In addition, the biological study consisted of evaluating antioxidant activity in vitro by five different methods (H2O2 radical reduction, DPPH, ABTS, FRAP and RP) and in vivo by SOD and MDA assays. RESULTS: The methanolic macerated is the richest in total polyphenols (102 ±â€¯1.38 mg EAG/gE), tannins (144.09 ±â€¯3.96 mg EC/gE) and flavonoids (17.25 ±â€¯0.06 mg ER/gE). The same extract has the highest percentage to inhibit hydrogen peroxide (19.24 ±â€¯1.10%) and the most potent reducing power of the ABTS radical (122.6 ±â€¯0.63 mg ET/gE). We also noted that aqueous macerated has the most potent anti-radical activity of DPPH with an IC50 of 2.78 ±â€¯1.03 µg/mL, the strongest reducing power of iron 96.15 ±â€¯1.12 mg EAA/gE and which was confirmed by the FRAP test (102.5 ±â€¯1.66 mg ET/gE). These results are in agreement with the in vivo study which showed an increase in SOD secretion in diabetic mice treated with aqueous macerated extract (904.26 ±â€¯29.10 units/g liver and 714.16 ±â€¯24.83 units/g kidney) and methanol macerated extract (813.61 ±â€¯24.03 units/g liver and 719.46 ±â€¯42.10 units/g kidney) with a statistically insignificant difference between these two extracts. Furthermore, we observed a return to normal MDA levels in mice treated with aqueous macerated extract (128.61 ±â€¯15.76 nM/g liver and 103.18 ±â€¯12.67 nM/g kidney) and methanol macerated extract (130.73 ±â€¯10.73 nM/g liver and 34.28 ±â€¯5.73 nM/g kidney). CONCLUSION: The aqueous and organic extracts more particularly those prepared by aqueous and methanolic macerations are rich in polyphenols, flavonoids and tannins, and they represent a rich source of natural antioxidants, also they prevent lipid peroxidation and stimulate the secretion of the enzymatic antioxidant SOD.