Inhibition of the growth of Plasmodium falciparum and Plasmodium berghei in vitro by an extract of Cochlospermum angolense (Welw.)

Pressurized Liquid Extraction for the Production of Extracts with Antioxidant Activity from Borututu (Cochlospermum angolense Welw.)

Borututu (Cochlospermum angolense Welw.) roots have been described as a rich source of phenolic compounds. Despite the potential of this plant for the production of bioactive extracts, studies reported until now have been scarce, and they have been based on the use of inefficient conventional extraction techniques. In this study, pressurized liquid extraction (PLE) was investigated for the production of borututu root extracts. Different temperatures (50–200 °C) and solvents (water, ethanol, and 50% ethanol:water) were applied. The total phenolic compound (TPC) content, the main phenolic compounds and the in vitro antioxidant activity of the extracts were evaluated. The results were compared with those obtained by conventional decoction with water. The highest concentrations of TPC and antioxidant activity were obtained with 50% ethanol:water, followed by water. The extract obtained with 50% ethanol:water at 150 °C had a TPC concentration of 343.80 mg/g and presented the largest antioxidant activity (1488 and 4979 µmol Trolox/g extract, determined by DDPH and ABTS assay, respectively). These values were considerably higher than those obtained by conventional decoction. Ellagic acid, and ellagic and methyl ellagic acid glycosides were the main phenolic compounds found in the extracts. Therefore, was PLE demonstrated to be a selective and efficient technique to obtain extracts with high concentrations of phenolic compounds and high antioxidant activity form borututu roots.

Comparing Medicinal Uses of Cochlospermaceae throughout Its Geographic Range with Insights from Molecular Phylogenetics

Species of the Cochlospermaceae, a small mostly pantropical plant family, were evaluated at a continental scale for medicinal uses in traditional medicine. This ethnobotanical information was placed in a phylogenetic framework to make informed predictions in the search for new medicines and bioactive compounds. Medicinal plant-use data were mapped onto a molecular phylogeny based on DNA sequences of nuclear and chloroplast markers. Associations of medicinal uses among closely related species occurring in different geographic regions and among diverse cultures were evaluated. The most common medicinal uses for these species are those used to treat skin ailments, gastro-intestinal problems, malaria, and liver issues. The plant species with the most numerous uses is Cochlospermum tinctorium, which occurs primarily in West Africa. Closely related species being used by cultural groups in different geographic regions to treat the same illnesses suggests the presence of bioactive compounds with potential biomedical value, since they may represent independent discoveries of similar medicinally-active compounds. This leads to the speculation that those closely related species not currently being used to treat these ailments may also contain identical or similar medicinally-active compounds and are worthy of laboratory investigations.

Hydroxybenzoic Acids Are Significant Contributors to the Antioxidant Effect of Borututu Bark, Cochlospermum angolensis Welw. ex Oliv

Borututu (Cochlospermum angolensis) is an African tree whose bark has recently emerged as a herbal dietary supplement with claims for antioxidant activity. In order to substantiate the claimed activity of borututu supplements, we performed an activity-guided fractionation of the total extract utilizing a 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay. Subsequent flash and centrifugal chromatography resulted in the isolation of gallic acid (1) and protocatechuic acid (2) as the main antioxidant constituents. Two apocarotenoids and one flavonoid were also isolated from the chloroform fraction and were identified as cochloxanthin (3), dihydrocochloxanthin (4), and 7,4′-dimethyltaxifolin (5), respectively. A High-performance liquid chromatography (HPLC) method was also developed for fingerprinting borututu samples, with Compounds 1–4 suggested as chemical markers for quality control purposes.

In Vitro and In Vivo Antimalarial Activity of Ficus thonningii Blume (Moraceae) and Lophira alata Banks (Ochnaceae), Identified from the Ethnomedicine of the Nigerian Middle Belt

Drug resistance in Plasmodium falciparum requires that new drugs must be developed. Plants are a potential source for drug discovery and development. Two plants that used to treat febrile illnesses in Nigeria were tested for in vitro and in vivo antimalarial activity and cytotoxicity in cancer cell lines. Methanol, hexane, and ethyl acetate leaf extracts of Ficus thonningii and Lophira alata were active in in vitro assays against P. falciparum NF54 (sensitive) and K1 (multiresistant) strains. Hexane extracts of F. thonningii and L. alata were the most effective extracts in in vitro assays with IC₅₀ of 2.7 ± 1.6 μg/mL and 2.5 ± 0.3 μg/mL for NF54 and 10.4 ± 1.6 μg/mL and 2.5 ± 2.1 μg/mL for K1 strain. All extracts were nontoxic in cytotoxicity assays against KB human cell line with IC₅₀ of over 20 μg/mL, demonstrating selectivity against P. falciparum. In vivo analysis shows that hexane extracts of both plants reduced parasitaemia. At the maximum dose tested, L. alata had a 74.4% reduction of parasitaemia while F. thonningii had a reduction of 84.5%, both extracts prolonged animal survival in mice infected with P. berghei NK65 when compared with vehicle treated controls. The antiplasmodial activity observed justifies the use of both plants in treating febrile conditions.

Ellagic acid and derivatives from Cochlospermum angolensis Welw. Extracts: HPLC-DAD-ESI/MS(n) profiling, quantification and in vitro anti-depressant, anti-cholinesterase and anti-oxidant activities

INTRODUCTION

Cochlospermum angolensis Welw. bark is a medicinal plant consumed for the treatment of hepatic diseases and for the prophylaxis of malaria. Nevertheless, there are few studies concerning its chemical composition and biological potential.

OBJECTIVE

Since phenolic compounds are described as powerful anti-oxidants and neuroprotective agents, the purpose of this study was to characterise the phenolic profile of this species and to extend the knowledge on its medicinal properties, namely its potential against oxidative stress, Alzheimer's disease and depression.

METHODS

The phenolic composition of aqueous and hydromethanolic extracts was characterised by HPLC-DAD-ESI/MS(n) . Anti-radical potential was tested against 2,2-diphenyl-1-picrylhdrazyl, superoxide anion and nitric oxide radicals, and neuroprotective effect was assessed against acetylcholinesterase, butyrylcholinesterase and monoamine oxidase A.

RESULTS

Eight compounds were characterised for the first time. Hydromethanolic extract was richer in methyl ellagic acid and its derivatives, while aqueous extract had higher amounts of ellagic acid and its derivatives. Methyl ellagic acid pentoside isomer and ellagic acid were the major compounds in the two extracts, respectively. Both extracts and ellagic acid revealed radical scavenging capacity stronger than that of ascorbic acid, but a weak effect on cholinesterases was observed. Their anti-depressant activity was also very strong.

CONCLUSION

The results provided evidence of the value of C. angolensis as a source of health-promoting anti-oxidants and anti-depressant compounds, with potential to be used as a raw product for food and pharmaceutical industries.

Evaluation of Volatile Constituents ofCochlospermum angolense

The chemical composition of the essential oils obtained from the leaves and roots of Cochlospermum angolense (Welw) growing wild in Angola was analyzed for the first time by capillary gas chromatography (GC) and gas chromatography/mass spectrometry (GC-MS). The investigation led to the identification of 67 and 130 compounds from the leaves and roots, respectively. Both oils were strongly characterized by the presence of sesquiterpenoids (68.8% in the leaves and 53.2% in the roots), while monoterpenoids were present in minor percentages (9.8% in the leaves and 26.2% in the root). The main constituents of the leaves were germacrene D (9.4%), α-cadinol (7.4%) and 10- epi-cubenol (6.2%), while the most abundant compounds in the root essential oil were the sesquiterpenes β-caryophyllene (19.7%) and isoborneol (6.6%). The analysis by HS-SPME of the roots, leaves, fruits and seeds were also reported for the first time. Different volatile profiles were detected.

In vitro antiplasmodial activity and cytotoxicity of ethnobotanically selected Ivorian plants

Eight extracts from four Ivorian medicinal plants, traditionally used to treat malaria, were tested for their antiplasmodial activity in vitro by assessing their ability to inhibit the uptake of [3H]hypoxanthine into the Plasmodium falciparum K1 chloroquine-resistant strain. The most active extract was the methylene chloride extract of Anogeissus leiocarpus which exhibited an IC(50) value of 3.8 micro g/ml. Inhibition of the growth of Plasmodium falciparum was also observed with the methylene chloride extract of Cochlospermum planchonii and Microdesmis keayana as well as with both methylene chloride and methanolic extracts of Hymenocardia acida.

In vitro antimalarial activity of limonoids from Khaya grandifoliola C.D.C. (Meliaceae)

The crude extract from the bark and seeds of Khaya grandifoliola was active in vitro against Plasmodium falciparum with an IC50 value of 13.23 microg/ml. The extract was purified to obtain seven limonoids--methylangolensate (1), 6-methylhydroxyangolensate (2), gedunin (3), 7-deacetylkhivorin (5), 1-deacetylkhivorin (6), swietenolide (7), 6-acetylswietenolide (8)--and one flavonoid, catechin (4). Five limonoids (1, 3, 5, 6, 8) were active with IC50 values between 1.25 and 9.63 microg/ml. Catechin was practically devoid of activity. The most active limonoid, gedunin, exhibited an additive effect when combined with chloroquine.

In vitro antiplasmodial activity of Central American medicinal plants

The in vitro antiplasmodial activities of 14 plant species traditionally used in Central America for the treatment of malaria or fever were evaluated. Lipophilic extracts of Piper hispidum, Siparuna andina, S. pauciflora, S. tonduziana, and Xylopia cf. frutescens, proved to be active against both a chloroquine-sensitive and a resistant strain of Plasmodium falciparum. IC50 values ranged between 3.0 microg/ml and 21.9 microg/ml; however, moderate cytotoxicity of active extracts was observed. Bioactivity-guided fractionation of Piper hispidum yielded 2',4, 6'-trihydroxy-4'-methoxydihydrochalcone (asebogenin) as an active compound.

In vivo and in vitro antiplasmodial activities of some plants traditionally used in Guatemala against malaria

We present an evaluation of the antiplasmodial and cytotoxic effects of four plants commonly used in Guatemalan folk medicine against malaria. Methanol extracts of Simarouba glauca D. C., Sansevieria guineensis Willd, Croton guatemalensis Lotsy, and Neurolaena lobata (L.)R.Br. significantly reduced parasitemias in Plasmodium berghei-infected mice. Dichloromethane fractions were screened for their cytotoxicities on Artemia salina (brine shrimp) larvae, and 50% inhibitory concentrations were determined for Plasmodium falciparum in in vitro cultures. Both chloroquine-susceptible and -resistant strains of P. falciparum were significantly inhibited by these extracts. Of all dichloromethane extracts, only the S. glauca cortex extract was considered to be toxic to nauplii of A. salina in the brine shrimp test.