Here, we report on a phyto-mediated bimetallic (NiFe2O4) preparation using a Boswellia carterii extract, which was characterized by XRD, FT-IR, TGA, electron microscopy, magnetic spectroscopy, and Mössbauer spectroscopy measurements. The prepared nano-catalysts were tested for oxidation of lignin monomer molecules—vanillyl alcohol and cinnamyl alcohol. In comparison with previously reported methods, the nano NiFe2O4 catalysts showed high photocatalytic activity and selectivity, under visible light irradiation with a nitroxy radical initiator (2,2,6,6-tetramethylpiperidinyloxy or 2,2,6,6-tetramethylpiperidine 1-oxyl; TEMPO) at room temperature and aerobic conditions. The multifold advantages of the catalyst both in terms of reduced catalyst loading and ambient temperature conditions were manifested by higher conversion of the starting material.

Abstract:From different plant parts of Calotropis species (C. gigantea and C. procera), various classes of compounds such as oxypregnanes, terpenoids, sterols, cardenolides and flavonoids have been isolated. Of these compounds, the cardenolides stand out as many of them have anticancer properties. Cardenolides are C 23 steroids with a five-membered unsaturated butyrolactone ring consisting of a steroid nucleus, a lactone moiety at C-17 and a sugar moiety at C-3. The roles of cardenolides in the treatment of human cancer have been established as they can induce apoptosis and inhibit the growth of cancer cells. Structure-activity relationship analyses have yielded some interesting findings on their cytotoxicity. Compounds with six-membered ring sugar groups generally have significantly stronger inhibitory activity than those with five-membered ring sugar groups. A formyl or methyl-hydroxyl group at C-10 enhances cytotoxicity while the presence of a 4´-OH or 16-OH group decreases cytotoxicity. Chemical modification of 2"-oxovoruscharin, a novel cardenolide extracted from the root bark of C. procera, has led to the synthesis of UNBS1450. The compound is characterized by more potent antiproliferative activity, lower toxicity, and is a strong sodium pump inhibitor and inducer of non-apoptotic cell death. UNBS1450 is currently in Phase I clinical trials.

Background: Jordan is a well-known country for its diversity in wild plants and for many decades, folk medicines represent part of its cultural heritage. In the present study, investigations have been focused on the therapeutic potential of Silybum marianum and Pergularia tomentosa on type 2 diabetes mellitus. In type 2 diabetes, which is considered a global health worry, the body cannot respond to or produce insulin hormone that raises the blood glucose level and the accompanied mortality, morbidity, healthcare expenses, and reduces the life quality. Dipeptidyl peptidase-IV (DPP-IV) enzyme, a serine protease, is responsible for deactivating incretin hormones that promote insulin secretion. Accordingly, DPP-IV inhibitory activity of these plant extracts that prolong the hypoglycemic effect of incretins was evaluated. Method: The aerial parts of S. marianum and P. tomentosa were dried, ground, and extracted with ethanol. The ethanol extract was dried under reduced pressure and was partitioned by methanol, butanol, and hexane according to a systematic procedure. The inhibition of DPP-IV enzyme by the different extracts was studied (at 10.0 mg/ mL concentration). Sitagliptin was used as the positive control. Results: Fortunately, most of the plant extracts have noticeable inhibitory activity against DPP-IV enzyme. It was found that the tested methanol extract of S. marianum has an inhibitory activity = 75.6% and the butanol extract of P. tomentosa = 73.6% which are analogous to DPP-IV inhibition of sitagliptin (78.5%), the used positive inhibitor. A superior inhibition of 98.1% was displayed for the butanol extract of S. marianum at 10.0 mg/ mL concentration. Conclusion: The revealed DPP-IV inhibitory activity of tested extracts advocates that their active constituents, particularly flavonoids, are capable of binding to the enzyme’s active cleft.

Two new cardenolides, named ischarin and ischaridin in addition to 10 known compounds, were isolated from Calotropis procera Ait. (Asclepiadaceae), growing wild in Jordan. Their structures were established mainly by the extensive application of one- and two-dimensional (1)H and (13)C-NMR spectroscopy.

Column chromatography (CC) analysis of methanol and butanol extracts of the aerial parts of Calortopis procera as well as the methanol extract of its latex, led to the isolation of 8 cardenolides, of which the structures were elucidated by NMR and HRESIMS spectroscopy. They also revealed several triterpenes and flavonoid glycoside. Based on the antiproliferative activity reported for cardenolides, the activity of calotropin and calotoxin was tested against two common cancer cell lines, human triple-negative breast cancer cell line (MDA-MB-231) and human lung adenocarcinoma cell line (A549). The high toxicity of the latex also encouraged performing the same test on the same cancer cell lines. The anti-proliferative activity of calotropin and calotoxin was compared to the methanol extract and the wax of the latex. The results showed that calotropin and calotoxin have significant cytotoxicity against MDA-MB-231 and A549 cell lines ranging from 0.046 to 0.072 μM compared to the methanol extract and the wax of its latex ranging from 0.47 to 58.41 μM. Moreover, the results showed lower toxicity of all treatments to the human skin fibroblasts compared to the toxicity to both MDA-MB-231 and A549 cancer cells lines except the higher toxicity of Methanolic extracts of C. procera latex to the MDA-MB-231 cells. In conclusion, C. procera is a medicinal plant with a wide spectrum of cardinolides including calotropin and calotoxin, which are promising agents for targeted cancer phytotherapy.