Cucurbitane-Type Triterpenes with Anti-proliferative Effects on U937 Cells from an Egyptian Natural Medicine, Bryonia cretica: Structures of New Triterpene Glycosides, Bryoniaosides A and B

Abstract

NoteBryonia cretica L., is a Cucurbitaceae plant growing widely in the western Mediterranean coastal region and in Egypt.1) This plant has been used in folk medicine as a drastic purgative, emetic, bitter tonic and anti-diabetic agent. 2)Previous chemical study of B. cretica revealed the presence of cucurbitacins B (3), E (5), I, and L.3) In the course of our studies on bioactive constituents from Egyptian natural medicines, 4-15) the 90% aqueous ethanolic (90% EtOH) extract from the roots of B. cretica showed strong inhibition of the proliferation of human leukemia U937 cells (IC 50 value at 72 hϭ0.035 mg/ml).Here we describe the chemical elucidation of two new cucurbitane-type triterpene glycosides, bryoniaosides A (1) and B (2), and anti-proliferative effects of several cucurbitanetype triterpenes (3-9) on U937 cells together with several structural requirements for the activity. Results and DiscussionThe 90% EtOH extract of the roots of B. cretica (11.5% from the dried roots) was partitioned into an ethyl acetate (EtOAc)-H 2 O (1 : 1, v/v) mixture to furnish the EtOAc-soluble fraction and an aqueous layer. The aqueous layer was extracted with n-butanol (n-BuOH) to give n-BuOH and H 2 Osoluble fractions. As shown in Table 1, the EtOAc-soluble fraction exhibited marked activity (IC 50 value at 72 hϭ 0.050 mg/ml), but the n-BuOH-and H 2 O-soluble fraction lacked the activity (IC 50 values at 72 hϾ1 mg/ml).The EtOAc-soluble fraction was subjected to normalphase and reversed-phase silica gel column chromatography and repeated HPLC to give two new cucurbitane-type triter-

Cucurbitacins-type triterpene with potent activity on mouse embryonic fibroblast from Cucumis prophetarum, cucurbitaceae

“…The spectral data of 1, is well fitted with published data with dihydocucurbitacin B, which was isolated from Bryonia cretica . [15] It is isolated from the first time from C. prophetarum of Saudi source.…”

“…For example, cucurbitacins were isolated from Cucumis prophetarum : cucurbitacin (B, E, I, O, P, and Q1); dihydocucurbitacin (D and E), isocucurbitacin (B, D, and E) and dihydroisocucurbitacin (D and E). [11–15]…”

Bryonia dioica aqueous extract induces apoptosis through mitochondrial intrinsic pathway in BL41 Burkitt's lymphoma cells

“…Externally, it is applied as a rubefacient to muscular and joint pains and pleurisy. It has been reported that the plant is used in folk medicine as a drastic purgative, emetic, bitter tonic and anti-diabetic agent (Matsuda et al, 2010). In different European countries it is considered to be a cicatrising agent (Guarrera and Lucia, 2007).…”

Structures of Novel Norstilbene Dimer, Longusone A, and Three New Stilbene Dimers, Longusols A, B, and C, with Antiallergic and Radical Scavenging Activities from Egyptian Natural Medicine Cyperus longus

“…Previously, we have reported on bioactive constituents from several Egyptian and Yemeni natural medicines such as Anastatica hierochuntica, 3,4) Nigella sativa, 5,6) Crinum yemense, 7) Dichrocephala integrifolia, 8) Citrullus colocynthis, 9) and Bryonia cretica. 10,11) We previously reported that the methanolic extract of the whole plant of C. longus exhibited 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging 12) and hepatoprotective activities. 13) By bioassay-guided separation, a novel norstilbene dimer, longusone A (1) with a tropilene skeleton, and three new stilbene dimers, longusols A (2), B (3), and C (4), and six sesquiterpenes, cyperusols A 1 , A 2 , B 1 , B 2 , C, and D, were isolated from the whole plant of C. longus.…”