Diazole and triazole derivatives of castor oil extract: synthesis, hypoglycemic effect, antioxidant potential and antimicrobial activity

The ricinoleate triglyceride was extracted from castor-oil seeds grown in Algeria and isolated by catalytically methanolyse to methyl ricinoleate. Six diazole and triazole derivatives of ricinoleic acid were synthesized and characterized: 1,3,4-oxadiazole-5-thione (4); 1,3,4-thiadiazole-5-thione (5); 4-N-amino-1,2,4-triazole-5-thiol (7); 1,2,4-triazole-5-thione (9); 5-amino-1,3,4-oxadiazole (10) and 5-amino-1,3,4-thiadiazole (11). The antibacterial and antifungal screening data of synthesized compounds showed appreciable inhibition and among them, 5, 7 and 8 showed more inhibition on Gram positive Enterococcus faecalis than reference ampiciline; while compounds 1, 7, 8, 10 and 11 showed competitive antifungal effects compared to reference amphotericin B. In addition, all synthesized compounds (1-11) showed competitive antioxidant properties, particularly compounds 7 at 125, 250, 500 and 1000 μg/mL and compounds 4, 5 and 9 at a concentration of 1000 μg/mL. The intermediate compounds 1, 2 and 8 showed anti-α-amylase activity at various concentrations in the range of IC50 = (120.25 ± 1.17 - 130.42 ± 2.48). Oxadiazole 4 showed the best α-amylase inhibition by 78.5% at a concentration of 1000 μg/mL.

Calcined Aceh Bovine Bone (Bos indicus) Intercalated Lithium as An Inorganic Base Catalyst for Transesterification of Castor Oil

Realizing abundant availability of local bovine bone wastes in Aceh Province, Indonesia, this study is subjected to take competitive advantages from the local bovine bone waste for preparing an inorganic catalyst preparation. In detail, calcined Aceh bovine bones were successfully intercalated lithium through an impregnation method resulting in the inorganic base catalyst, which showed promising activity in the transesterification of castor oil. Prior to the experiment, the Aceh bovine bone waste was calcined at 900 oC in the air atmosphere for 4 hours, led to forming crystalline phases of hydroxyapatite [Ca5(PO4)3(OH)] and calcium oxide [CaO]. Also, the chemical modification of calcined bovine bone with lithium precursor has enhanced the physicochemical properties of the inorganic base catalyst. Finally, the intercalated Aceh bovine bone has shown a feasible activity in transesterification of castor oil into biodiesel, which yielding methyl ricinoleate as the main product.

Bioactive compound profile of melon leaf extract (Cucumis melo L. ‘Hikapel’) infected by downy mildew

Pratama OA, Tunjung WAS, Sutikno, Daryono BS. 2019. Bioactive compound profile of melon leaf extract (Cucumis melo L. ‘Hikapel’) infected by downy mildew. Biodiversitas 20: 3448-3453. Plants express specific secondary metabolites (phytoalexin) in response to infection. Downy Mildew which infects melon plants (Cucumis melo L. ‘Hikapel’) caused by Pseudoperonospora cubensis Rostovtsev. Hikapel is one of superior melon cultivar produced from research in the Laboratory of Genetics, Faculty of Biology, Universitas Gadjah Mada, Yogyakarta, Indonesia. Bioactive content of Hikapel melon leaf under normal condition and infected by Downy Mildew yet to be researched. This research aims to screen bioactive profile of Hikapel leaf extract that has potential as phytomedicine. Leaf extract is compared between healthy plants and infected by Downy Mildew. Dried melon leaf was powdered using mortar and pestle. Leaf powder was extracted using hexane solvent. Extract was analyzed using a Shimadzu GCMS-QP2010S. Analysis found useful compounds like phytol, methyl ricinoleate, methyl linoleate, methyl stearate, and 1-hexacosanol. with therapeutic activity such as antibacterial, antifungal, antioxidant, antiinflammatory, antidiuretic, antidiarrheal, lowering blood LDL-C level, insulin level booster, antiproliferative, and anticancer. Some bioactive compounds are only synthesized in Hikapel melon leaf under stress conditions.