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Background: Inflammation is a natural body's defense mechanism against harmful stimuli such as pathogens, chemicals, or irradiation. But when the inflammatory response becomes permanent, it can lead to serious health problems. In the present study, the antioxidant and anti-inflammatory potentials of the Eriosema montanum methanolic extract (EMME), as well as its isolated fractions (FA-FJ) and compounds (1–7), were evaluated by using in vitro and cellular models. Methods: The total phenolic and flavonoid contents were determined using, respectively, Folin–Ciocalteu and aluminum chloride colorimetric methods, while 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 2,2′-diphenyl-1-picrylhy-drazyl (DPPH), and ferric ion reducing antioxidant power (FRAP) were used to determine the antioxidant activity. Thin Layer Chromatography (TLC) and column chromatography (CC) were used to isolate and purify the compounds and their elucidation using their NMR spectroscopic data. Results: EMME had moderate antioxidant and anti-inflammatory activities, while fraction FF showed much higher efficacy with IC50 values of 34.64, 30.60, 16.43, and 77.29 μg/mL against DPPH, ABTS, NO, and 15-LOX inhibitory activities, respectively. The EMME fraction was found to be very rich in flavonoids and phenolic compounds, with 82.11 mgQE/g and 86.77 mgGAE/g of dry extract, respectively. Its LC-MS profiling allowed us to identify genistin (5) as the most concentrated constituent in this plant species, which was further isolated together with six other known compounds, namely, n-hexadecane (1), heptacosanoic acid (2), tricosan-1-ol (3), lupinalbin A (4), d-pinitol (6), and stigmasterol glucoside (7). Given these compounds, genistin (5) showed moderate activity against reactive oxygen species (ROS) and NO production in LPS-stimulated RAW264.7 cells compared to EMME, which suggested a synergy of (5) with other compounds. To the best of our knowledge, compounds (1), (2), and (3) were isolated for the first time from this plant species. [ABSTRACT FROM AUTHOR]

Bioactive flavonoid epicatechin has been reported in the peel of litchi fruit but isolated from its hydroalcoholic extracts. This study isolated epicatechin with cellular glucose uptake modulatory and ROS production inhibitory properties from the ethyl acetate (EtOAc) extract using a bioassay-guided approach. The fruit peel was defatted with hexane and sequentially extracted using dichloromethane (DCM), EtOAc, methanol (MeOH) and water. In vitro phytochemical models, namely antioxidant (Fe3+ reducing, radical scavenging and anti-linoleic acid peroxidative) and glycaemic control (α-glucosidase and α-amylase inhibitory and glucose uptake modulatory), were employed for the bioassay-guided isolation, while the isolated compound was characterised using NMR and mass spectrometry and assessed for dose-dependent inhibition of α-glucosidase and lipopolysaccharide (LPS)-induced cellular ROS production, as well as modulation of cellular glucose uptake. Relative to the other extracts, the EtOAc extract had appreciable phenol and flavonoid contents, which perhaps influenced its potent anti-lipid peroxidative (65.0%) and α-glucosidase inhibitory (52.4%) effects. The α-glucosidase inhibitory potency of the fractions (1–8) from the EtOAc extracts correlated with their flavonoid contents, with fraction 5 outperforming other fractions. The fraction comprised a pool of fractions obtained from the DCM:MeOH:water (7:3:0.281 v/v/v) solvent system. LC-MS revealed the predominant presence of epicatechin in fraction 5, which was later isolated from one of the sub-fractions (sub-fraction 4) of fraction 5. This sub-fraction had stronger anti-lipid peroxidative (65.5%), α-glucosidase inhibitory (65.8%) and glucose uptake modulatory (38.2%) effects than the other sub-fractions from fraction 5, which could have been influenced by the isolated epicatechin. Moreover, the isolated epicatechin inhibited α-glucosidase (IC50 = 35.3 µM), modulated cellular glucose uptake (EC50 = 78.5 µM) and inhibited LPS-induced ROS production in RAW 264.7 macrophages in a dose-dependent fashion [IC50 = 18.9 µM; statistically comparable (p > 0.05) to ascorbic acid, IC50 = 9.57 µM]. Epicatechin from litchi peel EtOAc extract could potentiate glucose uptake modulatory, α-glucosidase inhibitory and ROS suppressive capacities, which could be influential in the use of litchi fruit peel for managing diabetes and associated oxidative damage. [ABSTRACT FROM AUTHOR]

Background: Sarcocephalus pobeguinii (Hua ex Pobég) is used in folk medicine to treat oxidative-stress related diseases, thereby warranting the investigation of its anticancer and anti-inflammatory properties. In our previous study, the leaf extract of S. pobeguinii induced significant cytotoxic effect against several cancerous cells with high selectivity indexes towards non-cancerous cells. Aim: The current study aims to isolate natural compounds from S. pobeguinii, and to evaluate their cytotoxicity, selectivity and anti-inflammatory effects as well as searching for potential target proteins of bioactive compounds. Methods: Natural compounds were isolated from leaf, fruit and bark extracts of S. pobeguinii and their chemical structures were elucidated using appropriate spectroscopic methods. The antiproliferative effect of isolated compounds was determined on four human cancerous cells (MCF-7, HepG2, Caco-2 and A549 cells) and non-cancerous Vero cells. Additionally, the anti-inflammatory activity of these compounds was determined by evaluating the nitric oxide (NO) production inhibitory potential and the 15-lipoxygenase (15-LOX) inhibitory activity. Furthermore, molecular docking studies were carried out on six putative target proteins found in common signaling pathways of inflammation and cancer. Results: Hederagenin (2), quinovic acid 3-O-[α-D-quinovopyranoside] (6) and quinovic acid 3-O-[β-D-quinovopyranoside] (9) exhibited significant cytotoxic effect against all cancerous cells, and they induced apoptosis in MCF-7 cells by increasing caspase-3/-7 activity. (6) showed the highest efficacy against all cancerous cells with poor selectivity (except for A549 cells) towards noncancerous Vero cells; while (2) showed the highest selectivity warranting its potential safety as a chemotherapeutic agent. Moreover, (6) and (9) significantly inhibited NO production in LPS-stimulated RAW 264.7 cells which could mainly be attributed to their high cytotoxic effect. Besides, the mixture nauclealatifoline G and naucleofficine D (1), hederagenin (2) and chletric acid (3) were active against 15-LOX as compared to quercetin. Docking results showed that JAK2 and COX-2, with the highest binding scores, are the potential molecular targets involved in the antiproliferative and anti-inflammatory effects of bioactive compounds. Conclusion: Overall, hederagenin (2), which selectively killed cancer cells with additional anti-inflammatory effect, is the most prominent lead compound which may be further investigated as a drug candidate to tackle cancer progression. [ABSTRACT FROM AUTHOR]

A new α-pyrone, asperpyrone (1) and two known compounds, stigmasterol (2) and 7-hydroxy-3-(2,3-dihydroxybutyl)-1(3H)-Isobenzofuranone (3) were isolated from the solid rice culture of the endophytic fungus Aspergillus sp., an endophytic fungus isolated from the fresh inner tissue of the barks of Garicinia smeathmannii. Their structures were determined by extensive spectral analysis including 1 D and 2 D NMR, HRESIMS and single-crystal X-ray crystallographic analysis. Asperpyrone (1) was tested against an axenic culture of Entamoeba moshkovskii, but did not exhibit any significant amoebicidal activity. [ABSTRACT FROM AUTHOR]

Several potential genotoxins found in water samples arise from anthropogenic activities. Acid mine effluent resulting from coal mining poses serious environment concerns all over the world. The use of toxicity tests to evaluate the quality of streams add value by providing site-specific toxicological data. Treatment systems such as the use of natural wetlands (passive) or conventional physical and chemical pH-neutralised processes (active) are employed mainly to meet certain water quality guidelines. Nonetheless, potential genotoxins or residues remain which influence the quality of discharged effluents. The objective of this study was to evaluate the genotoxic potential of acid mine drainage (AMD) released into a natural stream following treatment by passive and active methods. This study aimed to identify the extent of AMD mutagenicity and genotoxicity to African Vero monkey kidney cell line and a fish gill cell line (RTgill-W1) using two assays, the Ames test, and the comet assay, as a rapid and effective screening tool. The Ames test performed without metabolic activation using Salmonella typhimurium TA98 and TA100 strains showed no indication of mutagenicity in the water samples tested. Differing results were however obtained for the comet assay using the African Vero monkey kidney cell line and a fish gill cell line (RTgill-W1), which revealed DNA fragmentation and variations in morphologies indicative of genotoxicity in the water samples following the two treatment processes. A significant reduction in DNA damage was observed in water samples following active treatment of the AMD, evidenced by reduced damage frequency and a lowered comet score. This bioassay confirms the urgency of integrating high-throughput screening in aquatic toxicity assessment at genetic levels, giving further evidence that in-vitro bioassays can be incorporated for use in short-term genotoxicity assays. The result suggests that the comet assay proved sensitive at detecting genotoxicity, supporting the integration of this into environmental monitoring frameworks targeted at AMD-contaminated sites. [ABSTRACT FROM AUTHOR]

Background: Free radicals have been implicated in the pathogenesis of diverse metabolic disorders including cancer. Therefore, fighting against free radicals has become an important strategy in the prevention or treatment of such diseases, in addition to direct or indirect anticancer chemotherapy. Sarcocephalus pobeguinii has been used traditionally to treat various diseases in which excess production of free radicals is implicated, warranting investigation of its free radical scavenging, anticancer and anti-inflammatory activity. Methods: In the present study, extracts from leaves, fruits, roots and bark of Sarcocephalus pobeguinii were evaluated on four human cancer cell lines (MCF-7, HeLa, Caco-2 and A549 cells) and a non-cancerous cell line for their antiproliferative potential. The cells were incubated with the plant extracts for 48 h at 37 °C in a 5% CO2 humidified environment and their cytotoxic effect was determined using the tetrazolium-based colorimetric (MTT) assay. The radical inhibition was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging techniques. The nitric oxide inhibitory activity was determined using LPS-activated RAW 264.7 macrophages. The correlation between radical scavenging capacity and antiproliferative activity was also analysed. Results: The extract from leaves of Sarcocephalus pobeguinii (LSP) exhibited the highest cytotoxic effect on all four of the human cancer cell lines but with some cytotoxicity to the normal Vero cells. However, the LSP extract had the best selectivity index, ranging from 3.15 to 18.28. Also, antioxidant and anti-inflammatory assays indicated that the LSP extract had the highest radical scavenging capacity of all the extracts. A positive linear correlation was found between free radical scavenging ability and antiproliferative activity against the four cancer cell lines, with the highest correlation factor (R² = 0.9914) obtained between DPPH inhibition and antiproliferative activity against A549 cells. Conclusions: The high selectivity index of the Sarcocephalus pobeguinii leaf extract indicates the potential of using this extract in cancer therapy. Furthermore, the positive correlation between free radical scavenging and antiproliferative activity suggests that the radical scavenging capacity of extracts may contribute to a prediction of their anticancer property. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Codiaeum variegatum, grown in many varieties, has been widely used as a houseplant based on its brightly decorative foliage. In addition, a variety of this plant has been used for a long time against bloody diarrhea by the local population in Cameroon. Aim of the study In our previous study, the aqueous extract of this plant and an isolated sub-fraction exhibited significant anti-amoebic activity on axenic culture of Entamoeba histolytica. Due to the medicinal value of these extracts, we promptly initiated to investigate their genotoxic and mutagenic potential in order to assure their safe and rationale usage in traditional healthcare system. Material and methods Both extracts were incubated with L5178Y mouse lymphoma cells, primary hepatic cells and HepG2 human hepatocellular carcinoma cells and their genotoxicity and mutagenicity were evaluated by quantifying DNA damage and chromosomal aberrations through comet assay, micronucleus assay and mouse lymphoma mutation assay. Results The aqueous extract of Codiaeum variegatum is not cytotoxic up to 2000 µg/mL while the amoebicidal fraction is significantly cytotoxic (≤ 40-55%) on L5178Y mouse lymphoma and HepG2 cells at concentrations higher than 500 µg/mL. Besides, no significant DNA damage and induction of micronucleus formation were identified at concentrations up to 2000 µg/mL. Moreover, the mutagenic potential of these extracts after short (4 h) and long term (24 h) treatment, revealed no significant gene mutation induction. Conclusion The aqueous extract of Codiaeum variegatum and the amoebicidal fraction SF9B are neither genotoxic on non-competent or metabolic competent cell lines, nor mutagenic in mouse lymphoma mutation assay and therefore they could be safely used at lower doses for medicinal purpose. [ABSTRACT FROM AUTHOR]