From the aerial parts of Cymbidium ensifolium, three new dihydrophenanthrene derivatives, namely, cymensifins A, B, and C (1–3) were isolated, together with two known compounds, cypripedin (4) and gigantol (5). Their structures were elucidated by analysis of their spectroscopic data. The anticancer potential against various types of human cancer cells, including lung, breast, and colon cancers as well as toxicity to normal dermal papilla cells were assessed via cell viability and nuclear staining assays. Despite lower cytotoxicity in lung cancer H460 cells, the higher % apoptosis and lower % cell viability were presented in breast cancer MCF7 and colon cancer CaCo2 cells treated with 50 µM cymensifin A (1) for 24 h compared with the treatment of 50 µM cisplatin, an available chemotherapeutic drug. Intriguingly, the half-maximum inhibitory concentration (IC50) of cymensifin A in dermal papilla cells at >200 µM suggested its selective anticancer activity. The obtained information supports the further development of a dihydrophenanthrene derivative from C. ensifolium as an effective chemotherapy with a high safety profile for the treatment of various cancers.
1 June 2016 in Journal of Taibah University Medical Sciences
ObjectiveThis study sought to determine the antioxidant activities of African birch leaf, to assess its interaction with key enzymes relevant to type 2 diabetes (α-amylase and α-glucosidase) and to evaluate its effect on acarbose in vitro.MethodsOne milligram per milliliter of aqueous extract of African birch and acarbose were separately prepared. At the same time, both the African extract and acarbose solution (50:50 v/v) were thoroughly mixed until homogeneity was attained. The phenolic phytoconstituents and antioxidant properties of African birch leaf were subsequently determined. Finally, the effects of African birch extract, acarbose solution and a mixture of acarbose and African birch extract on α-amylase and α-glucosidase activities were assessed in vitro.ResultsThe results showed that African birch extract demonstrated a remarkable antioxidant effect, as exemplified by its radical scavenging abilities, Fe2+ chelating ability and prevention of lipid peroxidation. Acarbose had significantly (p < 0.05) higher α-amylase (IC50 = 11.77 μg/ml) and α-glucosidase (IC50 = 9.05 μg/ml) activities compared to African birch extract [α-amylase (IC50 = 242.17 μg/ml); α-glucosidase (IC50 = 196.35 μg/ml)]. However, the combination of acarbose and African birch extract showed an additive effect on α-amylase inhibition, while a resultant synergistic action was observed against α-glucosidase inhibition.ConclusionThe additive and synergistic actions of the combination of African birch extract and acarbose solution suggest effective, complementary and alternative strategies towards the management/treatment of hyperglycaemia associated with type 2 diabetes
1 December 2017 in Biochemistry and Biophysics Reports
•A focused on the erectogenic potentials of two tropical pumpkin seeds was established.•The antioxidant properties of these seed varieties were also discussed.•The inhibitory effects of the seeds on key enzymes relevant to ED were critically explored.•The potentials of the seeds to manage ED were recommended.