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In this study, an acidic polysaccharide from Codonopsis pilosula Nannf. var. modesta (Nannf.) L. T. Shen (WCP-I) and its main fragment, WCP-Ia, obtained after pectinase digestion, were structurally elucidated and found to consist of a rhamnogalacturonan I (RG-I) region containing both arabinogalactan type I (AG-I) and type II (AG-II) as sidechains. They both expressed immunomodulating activity against Peyer's patch cells. Endo-1,4-β-galactanase degradation gave a decrease of interleukine 6 (IL-6) production compared with native WCP-I and WCP-Ia, but exo-α-l-arabinofuranosidase digestion showed no changes in activity. This demonstrated that the stimulation activity partly disappeared with removal of β-d-(1→4)-galactan chains, proving that the AG-I side chain plays an important role in immunoregulation activity. WCP-Ia had a better promotion effect than WCP-I in vivo, shown through an increased spleen index, higher concentrations of IL-6, transforming growth factor-β (TGF-β), and tumor necrosis factor-α (TNF-α) in serum, and a slight increment in the secretory immunoglobulin A (sIgA) and CD4 + /CD8 + T lymphocyte ratio. These results suggest that β-d-(1→4)-galactan-containing chains in WCP-I play an essential role in the expression of immunomodulating activity. Combining all the results in this and previous studies, the intestinal immune system might be the target site of WCP-Ia.

Neutral polysaccharides from Ningxia L. barbarum fruit have been reported with immunomodulatory and antioxidative biological activities. Few studies on pectic polysaccharides have been reported, especially not from the Xinjiang L. barbarum. In the present study, a pectic polysaccharide, XLBP-I-I, was obtained from water decoction of Xinjiang L. barbarum using anion exchange chromatography and gel filtration. The results from methanolysis, methylation, FT-IR and NMR experiments indicated that XLBP-I-I was a typical pectic polysaccharide. In vitro assay showed that XLBP-I-I could reduce the ER stress and UPR in tunicamycin insult IPEC-J2 cells, and further protect IPEC-J2 cells against apoptosis induced by ER stress. These results reveal a new perspective for pectic L. barbarum polysaccharides on intestine ER stress, and this elicited interests for its further applications., (Copyright © 2019. Published by Elsevier B.V.)

Ethnopharmacological Relevance: Syzygium guineense has been traditionally used in Mali in West Africa for the treatment of different diseases such as stomach problems, wounds, inflammations and various female disorders., Aims of the Study: (1) To perform an ethnopharmacological survey on the traditional use of S. guineense among Malian healers. (2) To isolate and identify chemical constituents from S. guineense leaves and to study their radical scavenging and enzyme inhibitory effects., Materials and Methods: In four different districts in Mali, 44 healers were interviewed about their medicinal use of S. guineense. A methanol extract of the leaves of this tree was prepared and further fractionated using different chromatographic methods. Isolated compounds were identified by 1D and 2D NMR spectroscopy. Extracts and isolated compounds were investigated as DPPH radical scavengers and as inhibitors of xanthine oxidase and 15-lipoxygenase, and the methanol extract was tested for toxicity towards Artemia salina nauplii., Results: Major uses by Malian healers were against dermatosis, pain, malaria/fever and for wound healing. There was little consensus about the use in the different districts. Leaves were most commonly used. From the methanol leaf extract, the flavonoids gallocatechin (1), myricetin (2), myricetin-3-O-glucoside (3), myricetin-3-O-rhamnoside (4), myricetin-3-O-glucuronide (5) and myricetin-3-O-β-D-(6″-galloyl)galactoside (6), the gallotannins 1,2,3,6-tetra-O-galloyl-β-D-glucose (7) and 1,2,3,4,6-penta-O-galloyl-β-D-glucose (8), and the ellagitannins casuarictin (9) and casuarinin (10) were isolated. These ten polyphenols are all new for the species. The crude methanol extract was active as a radical scavenger and as an inhibitor of xanthine oxidase and 15-lipoxygenase. Among the isolated compounds, pentagalloylglucose was the best enzyme inhibitor (IC 50 25±4μM for 15-lipoxygenase, 8±1μM for xanthine oxidase), while casuarictin (IC 50 3.9±0.1μM), casuarinin (IC 50 4.5±0.3μM) and pentagalloylglucose (IC 50 5±1μM) showed the highest radical scavenging activity. The methanol extract was non-toxic to Artemia salina nauplii., Conclusion: S. guineense leaves are commonly used among Malian healers, however the traditional practice varies a lot between different regions. The leaves of S. guineense are rich in polyphenols; several are galloylated, either as galloylated flavonoids, gallotannins or ellagitannins. The high content of biologically active polyphenols might be important for medicinal effects of this plant and might give a rationale for the widespread usage of S. guineense in Mali., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: The root bark, stem bark and leaves of Terminalia macroptera have been traditionally used against a variety of ailments such as wounds, hepatitis, malaria, fever, cough, and diarrhea as well as tuberculosis and skin diseases in African folk medicine. Boiling water extracts of Terminalia macroptera, administered orally, are the most common preparations of this plant used by the traditional healers in Mali. This study aimed to investigate the inhibition of the activities of α-glucosidase, 15-lipoxygenase and xanthine oxidase, DPPH scavenging activity, complement fixation activity and brine shrimp toxicity of different extracts obtained by boiling water extraction (BWE) and by ASE (accelerated solvent extraction) with ethanol, ethanol-water and water as extractants from different plant parts of Terminalia macroptera., Materials and Methods: 27 different crude extracts were obtained by BWE and ASE from root bark, stem bark and leaves of Terminalia macroptera. The total phenolic and carbohydrate contents, enzyme inhibition activities (α-glucosidase, 15-lipoxygenase and xanthine oxidase), DPPH scavenging activity, complement fixation activity and brine shrimp toxicity of these extracts were evaluated. Principal component analysis (PCA) was applied for total biological activities evaluation., Results: Several of the extracts from root bark, stem bark and leaves of Terminalia macroptera obtained by BWE and ASE showed potent enzyme inhibition activities, radical-scavenging properties and complement fixation activities. None of the extracts are toxic against brine shrimp larvae in the test concentration. Based on the results from PCA, the ASE ethanol extracts of root bark and stem bark and the low molecular weight fraction of the 50% ethanol-water extract of leaves showed the highest total biological activities. The boiling water extracts were less active, but the bark extracts showed activity as α-glucosidase inhibitors and radical scavengers, the leaf extract being less active., Conclusion: The observed enzyme inhibition activities, radical scavenging properties and complement fixation activities may explain some of the traditional uses of this medicinal tree, such as in wound healing and against diabetes., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Context: Terminalia macroptera Guill. & Perr. (Combretaceae), a tree that grows in West Africa, has been used in traditional medicine against a variety of diseases such as hepatitis, gonorrhea, skin diseases, and diabetes., Objective: To investigate enzyme inhibitory activity against α-glucosidase and 15-lipoxygenase (15-LO) and toxicity against brine shrimp of extracts and compounds from T. macroptera leaves., Materials and Methods: Methanol extract, ethyl acetate, and butanol extracts obtained from the methanol extract, six isolated polyphenols (chebulagic acid, chebulic acid trimethyl ester, corilagin, methyl gallate, narcissin, and rutin), and shikimic acid were evaluated for enzyme inhibition and toxicity., Results: In enzyme inhibition assays, all extracts showed high or very high activity. Chebulagic acid showed an IC50 value of 0.05 µM towards α-glucosidase and 24.9 ± 0.4 µM towards 15-LO, in contrast to positive controls (acarbose: IC50 201 ± 28 µM towards α-glucosidase, quercetin: 93 ± 3 µM towards 15-LO). Corilagin and narcissin were good 15-LO and α-glucosidase inhibitors, as well, while shikimic acid, methyl gallate, and chebulic acid trimethyl ester were less active or inactive. Rutin was a good α-glucosidase inhibitor (IC50 ca. 3 µM), but less active towards 15-LO. None of the extracts or the isolated compounds seemed to be very toxic in the brine shrimp assay compared with the positive control podophyllotoxin., Conclusion: Inhibition of α-glucosidase in the gastrointestinal tract may be a rationale for the medicinal use of T. macroptera leaves against diabetes in traditional medicine in Mali. The plant extracts and its constituents show strong inhibition of the peroxidative enzyme 15-LO.

Ethnopharmacological Relevance: Water decoctions of the root bark, stem bark and leaves of Terminalia macroptera are used by traditional healers in Mali to cure a wide range of illnesses, such as wounds, hepatitis, malaria, fever, cough and diarrhea as well as tuberculosis. Plant polysaccharides isolated from crude water extracts have previously shown effects related to the immune system. The aims of this study are comparing the properties of the polysaccharides among different plant parts, as well as relationship between chemical characteristics and complement fixation activities when the plant material has been extracted as the traditional healers do, with boiling water directly., Materials and Methods: Root bark, stem bark and leaves of Terminalia macroptera were extracted by boiling water, and five purified polysaccharide fractions were obtained by anion exchange chromatography and gel filtration. Chemical compositions were determined by GC of the TMS derivatives of the methyl-glycosides and the linkage determined after permethylation and GC-MS of the derived partly methylated alditol acetates. The bioactivity was determined by the complement fixation assay of the crude extracts and purified fractions., Results: The acidic fraction TRBD-I-I isolated from the root bark was the most active of the fractions isolated. Structural studies showed that all purified fractions are of pectic nature, containing rhamnogalacturonan type I backbone. Arabinogalactan type II side chains were present in all fractions except TRBD-I-II. The observed differences in complement fixation activities among the five purified polysaccharide fractions are probably due to differences in monosaccharide compositions, linkage types and molecular sizes., Conclusion: The crude extracts from root bark and stem bark have similar total activities, both higher than those from leaves. The root bark, leaves and stem bark are all good sources for fractions containing bioactive polysaccharides. But due to sustainability, it is prefer to use leaves rather than the other two plant parts, and then the dosage by weight must be higher when using leaves., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

In Malian traditional medicine infusions of the roots of Vernonia kotschyana or Cochlospermum tinctorium in water are used for treating gastric ulcer. Helicobacter pylori is known to play a major role in gastric ulcer development, and it was of interest to evaluate a potential anti-adhesive activity towards H. pylori by crude water extracts and isolated polysaccharide fractions from the roots of V. kotschyana and C. tinctorium. The inhibitory effects were examined by an in vitro flow cytometric assay using human gastric adenocarcinoma epithelial cells, where fluorescent-labeled H. pylori were pre-treated with the test fractions. The crude extract Ctw50 from C. tinctorium, containing a mixture of inulin, pectic polysaccharides, phenols and protein, led to a 43% reduction of bacterial attachment. The isolated pectic type fractions CtwA1 and CtwA2 from C. tinctorium, and Vko-I from V. kotschyana resulted in approximately 30% inhibition of H. pylori adhesion. These fractions consist of rhamnogalacturonan backbones with side chains of arabinogalactans and/or arabinans. The low degree of uronic acids in the fractions compared to anti-adhesive polysaccharides reported previously, suggests that the neutral side chains might play a role in the binding of bacterial adhesins. The fraction Vko-III.1 from V. kotschyana consisting mainly of galacturonic acid resulted only in a 19% inhibition of H. pylori adhesion. The anti-adhesive properties shown by the crude water extracts and isolated polysaccharide fractions in the present study might partly explain the anti-ulcer activities by the roots of V. kotschyana and C. tinctorium., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Unlabelled: In Malian traditional medicine, aerial parts of Glinus oppositifolius are used in the treatment of many disorders, particularly inflammations and joint pains., Aim: The present study was initiated to investigate the antioxidant potential of Glinus oppositifolius., Material and Methods: Aqueous and ethanol extracts were prepared from the dried aerial parts. Both extracts were examined for the phenolic content and antioxidant activity. Total phenolic content was quantified by Folin-Ciocalteu method. Antioxidant activity was studied in vitro by evaluating the ability to scavenge different free radicals (ABTS, superoxide and hydroxyl radicals, nitric oxide) and to chelate ferrous ions., Results: Aqueous extract was found to contain a higher level of total phenols than ethanol extract (1.27 +/- 0.04 vs. 0.94 +/- 0.05 g GAE/100 g extract). Both extracts lacked the ability to scavenge superoxide anion radical but scavenged ABTS and hydroxyl radicals, nitric oxide and chelated ferrous ions in a concentration-dependent manner. According to the EC50 values, aqueous extract showed stronger antioxidant effects than ethanol extract (174.32 +/- 1.49 vs. 276.76 +/- 1.52 microg/mL in ABTS radical cation scavenging assay, 119.91 +/- 1.70 vs. 240.57 +/- 0.97 microg/mL in nitric oxide scavenging assay, 1.99 +/- 0.01 vs. 6.54 +/- 0.08 mg/mL in ferrous ion chelating assay). In hydroxyl radical scavenging assay, aqueous extract had an EC50 value of 0.86 +/- 0.00 mg/mL while the EC50 value of ethanol extract was higher than the highest concentration that was tested (3.75 mg/mL)., Conclusions: Our results clearly indicate the antioxidant potential of Glinus oppositifolius aerial parts and suggest that the antiinflammatory activity might be partly related to the antioxidant potential.

Ethnopharmacological Relevance: Sutherlandia frutescens (syn. Lessertia frutescens) is an indigenous plant in Southern Africa and has been extensively studied from the ethnobotanical point of view. Amongst the various traditional uses, several illnesses involving the immune system have been reported. Due to some of the therapeutic effects observed, in relation to the traditional uses reported by the "khoi san" and "nama" people on cancer related illnesses, the plant has been given the local name kankerbos (cancerbush). Recently the plant has also been used amongst HIV/AIDS patients to stimulate the immune system., Materials and Methods: Leaves of Sutherlandia frutescens were extracted sequentially with ethanol, 50% ethanol/water, and water at 50 and 100°C. The polysaccharides were extracted with water and fractionated by ion exchange chromatography and gel filtration to obtain enriched polysaccharide fractions. The bioactivities of the fractions were tested in the complement assay. Some of the fractions were treated with the enzyme pectinase, and the fragments thus produced were separated by gel filtration and their activities tested. Monosaccharide compositions and linkage analyses were determined for the relevant fractions., Results: The leaves of Sutherlandia frutescens contain polysaccharides of the pectin type. Fractions from both the water extracts of 50 and 100°C were bioactive. Fractions chosen for further studies showed that the fragment with the highest M(W) after the pectinase treatment had a substantially higher biological effect than the parent molecules. Based on a comparison of the different fractions it was concluded that galactose-rich regions were important for the bioactivity, these being of the AGII and AGI type, with the latter probably being more important than the former. Fragments rich in xylose also gave higher activity than those without it., Conclusions: Our theory that the polysaccharides present in the leaves of Sutherlandia frutescens could be of importance as immunomodulating agents was confirmed. It was also shown that certain types of polysaccharides had a higher effect in the complement system than others. Thus both the water extracts obtained at 50 and 100°C contain interesting biologically active polysaccharides., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

In Malian traditional medicine the roots of Cochlospermum tinctorium are used in the treatment of gastric ulcer, but extending harvesting is causing a growing concern of a dramatic reduction in the wild plant population. In the present study cultivation of C. tinctorium is evaluated, and structural components and bioactive properties of crude water extracts and isolated polysaccharide fractions from roots of wild and cultivated C. tinctorium are compared. The crude water extracts were shown to contain starch, pectin- and inulin-type polysaccharides, in addition to phenolic substances and protein, while the isolated acidic polysaccharide fractions contained mainly monosaccharides typical for pectins. The monosaccharide compositions of the polysaccharide fractions from roots of wild versus cultivated plants were comparable, albeit the yields in the cultivated roots were lower. Furthermore, the crude extracts and isolated polysaccharide fractions from wild and cultivated roots exhibited similar complement fixating activities, but were not able to activate macrophages. The crude extracts from cultivated roots were also shown to be moderate radical scavengers. The present study has shown that roots of cultivated C. tinctorium contain the same types of bioactive polysaccharides as the wild roots. However, in order to utilize roots of cultivated C. tinctorium in traditional medicine the cultivation method should be improved., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Ethnopharmacological Relevance: Ximenia americana is a medicinal bushy, spiny shrub or small tree used in Mali in West Africa for treatment of various diseases, most common are infectious and inflammatory ailments., Aims of the Study: (1) To perform an ethnopharmacological survey on the traditional use of Ximenia americana among healers in Mali. (2) To isolate and identify chemical constituents from the ethanol extract of Ximenia americana leaves and to study their radical scavenging and enzyme inhibitory effects., Materials and Methods: In five different districts in Mali, 38 healers were interviewed about their medicinal use of Ximenia americana. An aqueous ethanol extract of the leaves of this tree was prepared and further fractionated with liquid-liquid extraction, VersaFlash and Sephadex LH-20 column chromatography, and preparative HPLC. Isolated compounds were identified by 1D and 2D NMR spectroscopy. Extracts, subfractions and isolated compounds were investigated as DPPH radical scavengers and as inhibitors of xanthine oxidase and 15-lipoxygenase., Results: Major areas of use by Malian healers were against throat infection, amenorrhea and as tonic. Fractionation of the ethanol extract led to the isolation and identification of the cyanogenic glycoside sambunigrin (1), which is previously known from the plant. Additionally, gallic acid (2) and the gallotannins β-glucogalline (3) and 1,6-digalloyl-β-glucopyranose (4) were found. The following flavonoids were isolated: quercetin (5), quercitrin (quercetin-3-O-α-rhamnopyranoside) (6), avicularin (quercetin-3-O-α-arabinofuranoside) (7), quercetin-3-O-β-xylopyranoside (8), quercetin-3-O-(6″-galloyl)-β-glucopyranoside (9) and kaempferol-3-O-(6″-galloyl)-β-glucopyranoside (10). The flavonoids were active both as enzyme inhibitors and DPPH radical scavengers., Conclusion: Sambunigrin (1) was the main compound in the EtOAc soluble fraction of the alcoholic extract of Ximenia americana leaves. Gallic acid (2), gallotannins (3-4) and flavonoids (5-10) were identified for the first time in the genus Ximenia. The identified compounds may give a rationale for the traditional use of Ximenia americana in Mali. Healers interviewed reported the use against throat infections, amenorrhea, as tonic, for wound healing and against pain., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

The aerial parts of the medicinal plant Biophytum petersianum have a long tradition for being used in Mali and other West-African countries against various ailments such as wound healing and malaria. Previous studies on polysaccharides from water extracts of the aerial parts showed the presence of pectic like polymers with an effect on the human complement system as well as the ability to activate macrophages and dendritic cells. The present study shows that pectic polysaccharide fragments (BPII.1 and BPII.2) as well as the original pectic polysaccharide (BPII) expressed immunomodulating activity against Peyer's patch immunocompetent cells. Exo-β-D-(1→3)-galactanase digestion succeeded to decrease IL-6 production enhancing activity against Peyer's patch cells of BPII.2, but the activity of BPII.1 did not decrease. Endo-β-D-(1→4)-galactanase digestion reduced the activities of both BPII.1 and BPII.2. BPII.1 and BPII.2 also stimulated IL-6 production enhancing activity against macrophages, and the activities of both pectic fragments were significantly decreased by either enzymic digestion with exo-β-D-(1→3)-galactanase or endo-β-D-(1→4)-galactanase. Trimming of terminal GlcA by exo-β-D-glucuronidase digestion did not affect IL-6 production enhancing activity against macrophages of both pectic fragments. Methylation analyses of endo-β-D-(1→4)-galactanase digestion products showed the characteristic decrement of 4-linked Gal residues in the pectic fragments. These results suggest that β-D-(1→4)-galactan-containing side chains in BPII.1 and BPII.2 play an important role for expression of immunomodulating activity against both Peyer's patch immunocompetent cells and macrophages in addition to β-D-(1→3,6)-galactan chains., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

From a methanol extract of the leaves of the Malian medicinal tree Terminalia macroptera, cis-polyisoprene (1), chebulic acid trimethyl ester (2), methyl gallate (3), shikimic acid (4), corilagin (5), rutin (6), narcissin (7), chebulagic acid (8) and chebulinic acid (9), were isolated. Cispolyisoprene (1) was the major non-polar constituent. The novel compound 2 showed high radical scavenging activity (IC50 4.7 microg/mL), but was inactive as xanthine oxidase inhibitor. The major substituent of the crude extract, substance 5, showed a high radical scavenger effect (IC50 2.7 microg/mL) and weak xanthine oxidase inhibition (IC50 ca 105 microg/mL). The antioxidant and radical scavenging effects of some of the substances identified in this study may to some extent explain the medical use of this tree in West Africa.

The leaves of the tree Opilia celtidifolia have a long tradition for being used in Mali and other West African countries against various ailments such as for wound healing. Previous studies on polysaccharides from these leaves showed the presence of pectic-like polymers with an effect on the human complement system as well as the ability to activate macrophages. The present study shows that bioactive arabinogalactans isolated by water of 50°C could be separated into two acidic fractions, Oc50A1 and Oc50A2. The former could, by gel filtration on Sephacryl S-400, be separated into two fractions, which were further purified on a Superdex 200 column to give the fractions Oc50A1.I.pur and Oc50A1.II.pur. These fractions were subjected to chemical and biological studies. The polysaccharides consisted mainly of heavily branched type II arabinogalactans and minor amounts of rhamnogalacturonan I regions. The isolated polymers had a high human complement-fixating ability, as well as the ability to stimulate rat macrophages and dendritic cells (DCs) and to induce B cell proliferation. These effects were especially pronounced for the higher molecular weight fraction of Oc50A1.I.pur. The fractions Oc50A1.I.pur and Oc501.II.pur stimulated secretion of pro-inflammatory cytokines from purified B cells or DCs. Collectively, these results indicate that the arabinogalactan type II polymers present in the leaves of O. celtidifolia may be used to develop medical devices for regulating inflammatory processes.

This paper describes ethnopharmacological knowledge on the uses of Erythrina senegalensis DC (Fabaceae) in traditional medicine in three different areas (Dioila, Kolokani and Koutiala) in Mali. Data were collected using interviews of traditional healers selected randomly. The main reported diseases for which E. senegalensis was used by the traditional healers were amenorrhea, malaria, jaundice, infections, abortion, wound, and body pain (chest pain, back pain, abdominal pain etc). The fidelity level (which estimates the agreement of traditional healers on the same area about a reported use of the plant) was calculated to compare the results from the three areas. Certain differences were noticed, the most striking was the fact that amenorrhea was the most reported disease in Dioila and Kolokani with 21% of agreement for both areas, while this use was not reported in Koutiala at all. Similarities existed between the three areas on the use of the plant against malaria and infections, although with different degree of agreement among the healers. We also report the results of a literature survey on compounds isolated from the plant and their biological activities. A comparison of these results with the ethnopharmacological information from Mali and other countries showed that some of the traditional indications in Mali are scientifically supported by the literature. For instance, the use of E. senegalensis against infectious diseases (bilharzias, schistosomiasis, pneumonia etc.) is sustained by several antibacterial and antifungal compounds isolated from different parts of the plant. The comparison also showed that pharmacologists have not fully investigated all the possible bioactivities that healers ascribe to this plant.

Extracts of five medicinal plants: Boscia angustifolia, Cissus quadrangularis, Securidaca longipedunculata, Stylosanthes erecta and Trichilia emetica, used traditionally in Malian traditional medicine were screened for in vitro antiplasmodial activity and GABA(A)-benzodiazepine receptor binding activity. Four extracts showed significant antiplasmodial activities, with the dichloromethane extract of leaf of Securidaca longipedunculata being the most active (IC(50) of 7 microg/ml [95% CI: 5-9]). The dichloromethane extract of leaf of Trichilia emetica, in addition to its antiplasmodial activity (IC(50): 12 microg/ml [95% CI: 12-14]), exhibited a good binding activity to the GABA(A)-benzodiazepine receptor, while water and methanol extracts of the same plant did not show any activity. A strong GABA(A)-receptor complex binding activity was observed in the methanol extract of aerial part of Stylosanthes erecta. The results in this study justify some of the traditional indications of the plants investigated and may thus be candidates for Improved Traditional Medicines in Mali.

Traditional medicine, being a significant element in the cultural patrimony, still remains the main recourse for a large majority of people in Dogonland, Mali, for treating various diseases and ailments. This paper reports an ethnopharmacological study in Dogonland with the aim to identify medicinal plants used in the treatment of wounds. Information obtained from traditional healers revealed 73 plant species being used as wound healing remedies, according to the definitions of wounds given by the healers themselves. The plants, belonging to 34 plant families, are used as first aids, in the washing of wounds, extraction of pus, as coagulants, as well as for infected wounds. The most frequently used preparations are decoctions and powdered plant material.

Artemisia afra ( Jacq. Ex. Willd ), is an indigenous plant in South Africa and other parts of the African continent, where it is used as traditional medicine mostly for respiratory conditions. The objective of this study was to investigate the structural features of the polysaccharides from the leaves of this plant, as well as the biological activities of the polysaccharide fractions against the complement assay. Leaves of Artemisia afra were extracted sequentially with organic solvents (dichloromethane and methanol), 50% aqueous ethanol, and water at 50 and 100 °C respectively. The polysaccharide extracts were fractionated by ion exchange chromatography and the resulting fractions were tested for biological activity against the complement fixation assay. Active fractions were further fractionated using gel filtration. Monosaccharide compositions and linkage analyses were determined for the relevant fractions. Polysaccharides were shown to be of the pectin type, and largely contain arabinogalactan, rhamnogalacturonan and homogalacturonan structural features. The presence of arabinogalactan type II features as suggested by methylation analysis was further confirmed by the ready precipitation of the relevant polysaccharides with the Yariv reagent. An unusual feature of some of these polysaccharides was the presence of relatively high levels of xylose as one of its monosaccharide constituents. Purified polysaccharide fractions were shown to possess higher biological activity than the selected standard in the complement assay. Digestion of these polysaccharides with an endo -polygalacturonase enzyme resulted in polymers with lower molecular weights as expected, but still with biological activity which exceeded that of the standard. Thus on the basis of these studies it may be suggested that immunomodulating properties probably contribute significantly to the health-promoting effects of this medicinal plant. [ABSTRACT FROM AUTHOR]

Abstract: The African flora contains numerous medicinal plants whose biological and chemical properties are incompletely known. Antioxidant and radical scavenging properties of plants are subject to intensive research. In the work described here, we have investigated the antioxidant activity of the plants Diospyros abyssinica (root bark), Lannea velutina (root bark and stem bark) and Crossopteryx febrifuga (seeds). Extracts of different polarity were assayed for radical scavenging activity, using the stable free radical diphenylpicrylhydrazyl, and for inhibition of enzymatic lipid peroxidation mediated by soybean 15-lipoxygenase. All plants investigated showed activity, but there were large differences between plants and between extracts. In general, Diospyros abyssinica and Lannea velutina were richer in antioxidants than Crossopteryx febrifuga. Lipophilic extracts were not active as radical scavengers, but did inhibit 15-lipoxygenase. Semipolar extracts (80% aqueous ethanol and methanol) of Diospyros abyssinica and Lannea velutina showed the highest activity both as radical scavengers and lipoxygenase inhibitors, and also gave the highest extract yields. These plants therefore appear to be excellent sources of antioxidants. [Copyright &y& Elsevier]