Phytochemical analysis and anti-diabetic, anti-inflammatory and antioxidant activities of Loranthus acaciae Zucc. Grown in Saudi Arabia

Abstract

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.

Mechanism of antidiabetic effects of Plicosepalus Acaciae flower in streptozotocin-induced type 2 diabetic rats, as complementary and alternative therapy

“…These results agree with previous phytochemical studies that indicate that flavonoids, such as catechin, quercetin, rutin, gallic acid, methyl gallate, and loranthin, a new flavanocoumarin, are the major active constituents of PA that contribute to its high radical scavenging activity [ 16 , 17 , 39 ].…”

“…Many phenolic compounds were isolated from PA (also named Loranthus Acacia ) such as catechin, quercetin, rutin, gallic acid, methyl gallate, and loranthin (a new flavanocoumarin), showed high antioxidant activities [ 16 ]. The phytochemical analysis of PA led to the isolation and characterization of four compounds namely, quercetin 3-O-b-Dglucopyranoside, quercetin 3-O-b-(6-O-galloyl)-glucopyranoside, (−) catechin, and catechin 7-O-gallate [ 17 ].…”

In vitro tissue culture, preliminar phytochemical analysis, and antibacterial activity of Psittacanthus linearis (Killip) J.K. Macbride (Loranthaceae)

“…The phytochemical analysis of L acaciae led to the isolation and characterization of quercetin 3-O-ꞵ-D-glucopyranoside, quercetin 3-O-ꞵ-(6-O-galloyl)-glucopyranoside, (-) catechin, and catechin 7-O -gallate. Among these compounds quercetin 3-O-ꞵ-Dglucopyranoside, quercetin 3-O-ꞵ-(6-O-galloyl)glucopyranoside and catechin 7-O-gallate, were isolated for the first time from this species (Noman et al, 2019). In Plicosepalus curviflorus (Oliv.)…”

“…On the other hand, a in vitro study about the anti-diabetic properties from hemiparasitic species of D. falcata revealed that its plant's leaves extracts had inhibitory activity on the key enzyme alpha-amylase, which enzyme breaks the large strach molecules that produces free glucose and simultaneously increases the blood sugar level, and consequently hyperglycemia (Naskar et al, 2019). Likewise, the cloroform fraction and crude extract from Loranthus acaciae Zucc grown in Saudi Arabia showed anti-diabetic, anti-inflammatory and antioxidant activities (Noman et al, 2019). Leaves from Scurrula parasitica L., quercetin, quercitrin, kaempferol 3-O-α-Lrhamnoside, (+)-catechin compounds, together with ethyl acetate and methanol extracts exhibited effective antioxi-dant activities against DPPH(2,2-diphenyl-1-picrylhydrazyl), ABTS[2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)] and FRAP (Ferric reducing antioxidant potential), while n-hexane and other compounds were inactive (Muhammad et al, 2019).…”

Isolation, Characterization, and HPTLC-Quantification of Compounds with Anticancer Potential from Loranthus Acaciae Zucc.

“…Moreover, phytochemical investigations have led to the isolation and identification of phenolic compounds exhibiting free radical scavenging activity [11,12]. We recently reported about the antidiabetic, anti-inflammatory, and antioxidant activities, as well as isolation and identification of four flavonoid derivatives, namely, quercetin 3-O-β-d-glucopyranoside, quercetin 3-O-β-(6-O-galloyl)-glucopyranoside, (−)-catechin, and catechin 7-O-gallate, from the chloroform fraction of L. acaciae [13]. Furthermore, several other studies have demonstrated the anticancer properties of various members of the Loranthaceae family, such as Loranthus micranthus, Loranthus parasiticus, and Loranthus ferrugineus [14][15][16].…”