Antioxidant and Antiproliferative Potentials of Ficus glumosa and Its Bioactive Polyphenol Metabolites.

Ficus glumosa Delile (Moraceae), a reputed plant that is used in herbal medicine, is of high medicinal and nutritional value in local communities primarily ascribed to its phytochemical profile. Currently, there are hardly any fine details on the chemical profiling and pharmacological evaluation of this species. In this study, the flavonoids and phenolics contents of the ethanol extracts and four extracted fractions (petroleum ether (PE), ethyl acetate (EA), n-butanol, and water) of the stem bark of Ficus glumosa were firstly quantified. Further, their antioxidant and antiproliferative potentials were also evaluated. The quantitative determination indicated that the EA and n-butanol fractions possessed the highest total flavonoids/phenolics levels of 274.05 ± 0.68 mg RE/g and 78.87 ± 0.97 mg GAE/g, respectively. Similarly, for the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric-reducing antioxidant power (FRAP) assays, the EA fraction exhibited high potency in both DPPH and ABTS+ scavenging activities with IC50 values of 0.23 ± 0.03 mg/mL, 0.22 ± 0.03 mg/mL, and FRAP potential of 2.81 ± 0.01 mg Fe2+/g, respectively. Furthermore, the EA fraction displayed high cytotoxicity against human lung (A549) and colon (HT-29) cancer cells. Additionally, the liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) was employed in order to characterize the chemical constituents of the EA fraction of Ficus glumosa stem bark. Our findings revealed 16 compounds from the EA fraction that were possibly responsible for the strong antioxidant and anti-proliferative properties. This study provides edge-cutting background information on the exploitation of Ficus glumosa as a potential natural antioxidant and anti-cancer remedy.

Hypoglycemic and hypolipidemic effects of Moringa oleifera leaves and their functional chemical constituents.

Moringa oleifera Lam. (M. oleifera) leaves have long been consumed as both nutritive vegetable and popular folk medicine for hyperglycemia and hyperlipidemia in Kenya communities. In the current study, in vitro inhibition by M. oleifera leaf extract (MOLE, 90% (v/v) ethanol) of α-glucosidase and pancreatic lipase was demonstrated, followed by determination of the effects of MOLE on both glucose consumption and lipid levels (TC, TG, HDL-C and LDL-C) in 3T3-L1 cells. Potential ligands in MOLE were fast screened using affinity ultrafiltration LC-MS, and 14 and 10 components displayed certain binding affinity to α-glucosidase and pancreatic lipase, respectively. Docking studies revealed the binding energies and hydrogen bonds between potential ligands and enzymes. This study suggests that M. oleifera leaves may be a promising natural source for the prevention and treatment of hyperglycemia and hyperlipidemia as well as a functional food or other product for health care in the near future.

Antioxidant, Anti-inflammatory Activities and Polyphenol Profile of Rhamnus prinoides.

Rhamnus prinoides L'Herit (R. prinoides) has long been widely consumed as folk medicine in Kenya and other Africa countries. Previous studies indicated that polyphenols were abundant in genus Rhamnus and exhibited outstanding antioxidant and anti-inflammatory activities. However, there are very few studies on such pharmacological activities and the polyphenol profile of this plant up to now. In the present study, the antioxidant activities of the crude R. prinoides extracts (CRE) and the semi-purified R. prinoides extracts (SPRE) of polyphenol enriched fractions were evaluated to show the strong radical scavenging effects against 1,1-diphenyl-2- picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) (0.510 ± 0.046 and 0.204 ± 0.005, mg/mL), and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) (0.596 ± 0.005 and 0.096 ± 0.004, mg/mL), respectively. Later, the SPRE with higher contents of polyphenols and flavonoids displayed obvious anti-inflammatory activities through reducing the NO production at the dosage of 11.11 - 100 µg/mL, and the COX-2 inhibitory activity with an IC50 value at 20.61 ± 0.13 µg/mL. Meanwhile, the HPLC-UV/ESI-MS/MS analysis of polyphenol profile of R. prinoides revealed that flavonoids and their glycosides were the major ingredients, and potentially responsible for its strong antioxidant and anti-inflammatory activities. For the first time, the present study comprehensively demonstrated the chemical profile of R. prinoides, as well as noteworthy antioxidant and anti-inflammatory activities, which confirmed that R. prinoides is a good natural source of polyphenols and flavonoids, and provided valuable information on this medicinal plant as folk medicine and with good potential for future healthcare practice.

In Vitro Antibacterial and Antiproliferative Potential of Echinops lanceolatus Mattf. (Asteraceae) and Identification of Potential Bioactive Compounds.

Many species belonging to the genus Echinops are widely used in traditional medicine to treat infectious diseases and cancers. The present study aimed to evaluate the antibacterial and antiproliferative properties of Echinops lanceolatus Mattf. (Asteraceae). The activity of the methanolic extract and subsequent partition fractions was investigated against drug-resistant bacteria (Gram-negative and Gram-positive) and human tumor cell lines using broth microdilution and sulforhodamine B (SRB) assay, respectively. Our findings revealed weak to moderate antibacterial activities of tested extracts, with the recorded minimal inhibitory concentrations ranging from 256 to 1024 µg/mL. The ethyl acetate fraction (EL-EA) was found to be the most effective. Likewise, that fraction displayed strong antiproliferative potential with recorded IC50 of 8.27 µg/mL and 28.27 µg/mL on A549 and HeLa cells, respectively. An analysis based on the ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) of the EL-EA fraction allowed the identification of 32 compounds, of which quinic acid and derivatives, cinnamic acid derivatives, dihydrokaempferol, naringenin-7-O-glucoside, apigenin-7-O-d-glucoside, naringin, apigenin, rhoifolin, coniferyl aldehyde, and secoisolariciresinol are well-known compounds of biological importance. This study is first to report on the biological activity and phytochemical profile of E. lanceolatus. We provide a baseline to consider E. lanceolatus as a valuable source of anti-infective and antiproliferative agents.

Antioxidant and Anti-Inflammatory Activities of the Crude Extracts of Moringa oleifera from Kenya and Their Correlations with Flavonoids.

Moringa oleifera Lam. (M. oleifera) is commonly distributed and utilized in tropical and sub-tropical areas. There has been a large number of reports on the antioxidant and anti-inflammatory activity of its leaves, but only a few about its seeds and roots. Hence, in this work we aimed to systematically compare the antioxidant and anti-inflammatory activities of the ethanol crude extracts of leaves, seeds, and roots of M. oleifera from Kenya, and further correlate the differential activities with the chemical constituents from these three parts. The antioxidant activities were measured by using three different assays (DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) and FRAP (Ferric-Reducing Antioxidant Power), respectively). Results showed that the leaf extracts displayed the highest DPPH radical scavenging and FRAP total reducing power activities with IC50 values of 1.02 ± 0.13 mg/mL and 0.99 ± 0.06 mM Fe2+/g, respectively; the leaf and root extracts exhibited potential ABTS radical scavenging activities with the IC50 values of 1.36 ± 0.02 and 1.24 ± 0.03 mg/mL. Meanwhile, the leaf and seed extracts (11.1-100 µg/mL) also exerted obvious anti-inflammatory activities, as indicated by the inhibition of NO production. To further reveal correlations between these differential activities with the chemical constituents in the three organs, the total flavonoids content (TFC) of the three different extracts were evaluated, and the TFC of leaves, seeds and roots were found to be 192.36 ± 2.96, 5.89 ± 0.65 and 106.79 ± 2.12 mg rutin equivalent (RE)/g, respectively. These findings indicated the important impacts of the total flavonoid contents on antioxidant and anti-inflammatory activities. Additionally, we further determined the phytochemical profiles of M. oleifera by HPLC-UV/ESI-MS/MS, and identified most of the chemical constituents of leaves as flavonoids. In summary, the leaves of M. oleifera are a better potential natural source of antioxidants and anti-inflammatory agents, and very promising for development into the health promoting dietary supplements.