The traditional medicine based on medicinal plants in the Kingdom of Arabia Saudia presents a strong relationship belonging to natural remedies, health, diet, and folk healing practice recognized by a specific culture. The aim of the current study is to carry out an ethnobotanical review on medicinal plants used in traditional medicine in the Kingdom of Arabia Saudia including information on plant species, used parts, preparation method as well as medical uses. Earlier published data in journals, textbooks, periodicals, websites, and databases written in pharmacological evidence of Suadi medicinal plants were based on gathering information. The present review work reported that 96 species belonging to 47 families have been used in Saudi Pharmacopeia. Amaranthaceae has the highest number of plant species (7) Followed by Asteraceae, Apocynaceae, and Fabaceae with 5 plant species in each. The inventoried plant species in the current work are frequently used for the treatment of various illnesses and to ensure the medication safety of Saudi people. The biological analysis of plant form used in Saudi natural remedies showed the dominance of herb and subshrub form with a percentage of 43% and 30% respectively. The most used preparation method of plant drugs, which used in Saudi Alternative medicine was decoction and infusion. The whole plant, leaves, seeds, and aerial parts were the most useful plant parts in natural preparation in Saudi traditional medicine with a percentage of 29%, 28%, 7%, and 5% respectively as reported in the present review work. The present review work gives big data about medicinal plants used in traditional medicine in the Kingdom of Saudi Arabia including data about plant species, used parts, preparation method as well as medical uses.

Natural-based drugs are believed to be safe, effective and economical. Based on the medicinal importance of the genus Eryngium and unexplored nature of Eryngium caeruleum, we have evaluated its antidiabetic and antioxidant potentials. Both in-vitro and in-vivo assays have been carried out for antidiabetic assays. The antioxidant activity was determined by using different free radicals [i.e., 1,1-diphenyl,2-picrylhydrazyl (DPPH), 2,2-azinobis[3-ethylbenzthiazoline]-6-sulfonic acid (ABTS), and hydrogen peroxide (H2O2)]. Moreover, different phytoconstituents were identified in the most active solvent fraction by GC-MS analysis. Furthermore, comparative fingerprints of methanolic extract and chloroform fraction were also analyzed via High Performance Liquid Chromatography coupled with Diode Array Detector (HPLC-DAD). The crude methanolic extract of E. caeruleum (Ec.Cr) and its sub-fractions [i.e., n-hexane (Ec.Hex), chloroform (Ec.Chf), ethyl acetate (Ec.EtAc), and aqueous (Ec.Aq) were employed in this study]. In the α-glucosidase inhibition assay, a concentration-dependent inhibitory response was observed against the enzyme. The most active sample was Ec.Chf which revealed an IC50 of 437 μg/ml in comparison to the standard acarbose (IC50 25 μg/ml). The rest of the samples showed moderate inhibition of α-glucosidase. In antioxidant assays, Ec.Chf and Ec.Cr exhibited a considerable scavenging effect against all the free radicals. The IC50 values recorded for Ec.Chf were 112, 109, and 150 μg/ml against DPPH, ABTS, and H2O2 respectively. Based on the in-vitro potential of Ec.Chf, this was subjected to the in-vivo model experiment. The Ec.Chf lowered the blood glucose level up to 10.3 mmol/L at 500 μg/Kg. The Ec.Chf was also subjected to GC-MS analysis. The GC-MS analysis confirmed the presence of 60 compounds. The identified phytoconstituents consist of some essential compounds previously reported with antidiabetic and antioxidant studies, which include thymol, tocopherol, phytol, nerolidol, (I)-neophytadiene, linolenic acid, and falcarinol. Similarly, the HPLC-DAD chromatograms of Ec.Cr and Ec.Chf exhibited a variety of peaks, which further demonstrates the possibility of important phytochemicals. In a nutshell, we can conclude that Eryngium caeruleum is a potential source of bioactive compounds which may be beneficial for the management of ailments like diabetes and free radicals mediated disorders. Molecular docking was performed to explore the possible role of all the identified bioactive compounds in the chloroform fraction of Eryngium caeruleum into active sites of the homology model of α-glucosidase.

Apigenin (APG) is a very well-known flavonoid for its anti-inflammatory and anticancer properties. The purpose of this study is to improve the solubility and bioavailability of APG using a stable bioactive self-nanoemulsifying drug delivery system (Bio-SNEDDS). APG was incorporated in an oil phase comprising coconut oil fatty acid, Imwitor 988, Transcutol P, and HCO30 to form a Bio-SNEDDS. This preparation was characterized for morphology, particle size, and transmission electron microscopy (TEM). The APG performance was investigated in terms of loading, precipitation, release and stability tests from the optimal Bio-SNEDDS. An antimicrobial test was performed to investigate the activity of the Bio-SNEDDS against the selected strains. Bioavailability of the Bio-SNEDDS was evaluated using Wister rats against the commercial oral product and the pure drug. The results demonstrated the formation of an efficient nanosized (57 nm) Bio-SNEDDS with a drug loading of 12.50 mg/gm which is around 500-fold higher than free APG. TEM analysis revealed the formation of spherical and homogeneous nanodroplets of less than 60 nm. The dissolution rate was faster than the commercial product and was able to maintain 90% APG in gastro intestinal solution for more than 4 h. A stability study demonstrated that the Bio-SNEDDS is stable at a harsh condition. The in vivo pharmacokinetics parameters of the Bio-SNEDDS formulation in comparison to the pure drug showed a significant increase in maximum concentration (Cmax) and area under the curve (AUC (0–t)) of 105.05% and 91.32%, respectively. Moreover, the antimicrobial study revealed moderate inhibition in the bacterial growth rate. The APG-Bio-SNEDDS could serve as potential carrier aimed at improving the clinical application of APG.

Withania frutescens L. is a wild perennial woody plant used by the local population for diverse therapeutic purposes. This work aims to study for the first time the potential inhibitory effect of this plant hydroethanolic extract on α-amylase and α-glucosidase activities using in vitro methods and its antidiabetic and antihyperglycemic activities using alloxan-induced diabetic mice as a model for experimental diabetes. Two doses were selected for the in vivo study (200 and 400 mg/kg) and glibenclamide, a well-known antidiabetic drug (positive control) in a subacute study (28 days) where the antihyperglycemic activity was also assessed over a period of 12 h on diabetic mice. The continuous treatment of diabetic mice with the extract of Withania frutescens for 4 weeks succeeded to slowly manage their high fasting blood glucose levels (after two weeks), while the antihyperglycemic test result revealed that the extract of this plant did not control hyperglycemia in the short term. No toxicity signs or death were noted for the groups treated with the plant extract, and it shows a protective effect on the liver and kidney. The in vitro assays demonstrated that the inhibition of alpha-amylase and alpha-glucosidase might be one of the mechanisms of action exhibited by the extract of this plant to control and prevent postprandial hyperglycemia. This work indicates that W. frutescens have an important long term antidiabetic effect that can be well established to treat diabetes.

Coriandrum sativum L. seeds are traditionally used to treat diabetes and its complications (inflammation and formation of reactive oxygen species) around the world. The present study investigates the antidiabetic, anti-inflammatory, and antioxidant effects of the polyphenol fraction of Coriandrum sativum seeds (PCS). Diabetic mice were orally administered with PCS (25 and 50 mg/kg b.w.) for 28 days. Oral glucose tolerance (OGTT) was also evaluated along with the anti-inflammatory effect, assessed by measuring paw edema development induced with carrageenan in Wistar rat and the antioxidant activity assessed using two tests (β-carotene discoloration and DPPH). Treatment of diabetic mice with PCS for four weeks managed their high fasting blood glucose levels, improved their overall health, also revealed an excellent antihyperlipidemic activity. The OGTT result showed a potent antihyperglycemic activity, and following the anti-inflammatory and antioxidant effects, the PCS exhibited a perfect activity. LC-MS/MS result revealed the presence of 9 polyphenols. This modest work indicates that the PCS have an important antidiabetic, antihyperglycemic, antihyperlipidemic, anti-inflammatory, and antioxidant effect that can be well established treatment of diabetes and its complications.

Sphingosine kinase 1 (SphK1) has recently gained attention as a potential drug target for its association with cancer and other inflammatory diseases. Here, we have investigated the binding affinity of dietary phytochemicals viz., ursolic acid, capsaicin, DL-α tocopherol acetate, quercetin, vanillin, citral, limonin and simvastatin with the SphK1. Docking studies revealed that all these compounds bind to the SphK1 with varying affinities. Fluorescence binding and isothermal titration calorimetric measurements suggested that quercetin and capsaicin bind to SphK1 with an excellent affinity, and significantly inhibits its activity with an admirable IC50 values. The binding mechanism of quercetin was assessed by docking and molecular dynamics simulation studies for 100 ns in detail. We found that quercetin acts as a lipid substrate competitive inhibitor, and it interacts with important residues of active-site pocket through hydrogen bonds and other non-covalent interactions. Quercetin forms a stable complex with SphK1 without inducing any significant conformational changes in the protein structure. In conclusion, we infer that quercetin and capsaicin provide a chemical scaffold to develop potent and selective inhibitors of SphK1 after required modifications for the clinical management of cancer.

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The Loranthus genus has been demonstrated to be used in the treatment of wide range of diseases e.g. diabetes, inflammations and cancers. Many species of Loranthus represent a major source of biologically active constituents. Therefore, our study was carried out to investigate the anti-diabetic, anti-inflammatory and antioxidant effects of Loranthus acaciae Zucc. (Loranthaceae) grown in Saudi Arabia. Moreover, our research concerned the guided-fractionation and isolation of possible active compounds from this species. The crude ethanolic extract and its n-hexane, chloroform and n-butanol fractions were investigated for antidiabetic activity utilizing two methods namely, in alloxan-induced diabetic rats and glucose tolerance test in normal rats. Additionally, the anti-inflammatory activity was studied by the carrageenan-induced rat paw oedema method while DPPH free radical scavenging and β-carotene bleaching assays were utilized to determine the antioxidant activity. Various chromatographic and spectroscopic techniques were utilized for the isolation and characterization of the active compounds. Our results exhibited that the crude extract and chloroform fraction has the greatest hypoglycemic and antidiabetic effects. The chloroform fraction and crude extract produced at a dose of 500 mg/kg a significant hypoglycemic effect in diabetic rats with 47.0 and 33.6% reduction in blood sugar levels and in normoglycemic rats 35.6 and 35.4% respectively. A potent anti-inflammatory effect (67.2% at 500 mg/kg) was detected for the chloroform fraction. In addition, the chloroform fraction exhibited a high antioxidative and DPPH-radical inhibitory activity (85.4 and 88.3% respectively). The phytochemical analysis of L. acaciae led to the isolation and characterization of four compounds namely, quercetin 3-O-β-D-glucopyranoside (compound 1), quercetin 3-O-β-(6-O-galloyl)-glucopyranoside (compound 2), (-) catechin (compound 3), and catechin 7-O-gallate (compound 4). Among these compounds quercetin 3-O-β-D- glucopyranoside, quercetin 3-O-β-(6-O-galloyl)-glucopyranoside and catechin 7-O-gallate, are isolated for the first time from this plant.