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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.)

Defatted leaves from the medicinal tree Cola cordifolia were extracted with 50% EtOH, 50 °C and 100 °C water. The polysaccharide rich extracts were fractionated and the structure of the polysaccharides elucidated. Linkage analysis of the polysaccharides indicates a rhamnogalacturonan type I backbone where both Rha and parts of GalA are substituted in position 3, indicating a highly branched polymer with short side chains. The purified fractions were tested for complement fixation, macrophage stimulating activity and anti-adhesion activity towards Helicobacter pylori. Here we report on complex and polydisperse types of pectins (Mw: 3-1300 kDa) as well as the presence of low Mw (<3 kDa) acidic oligosaccharides. The fractions showed a moderate complement fixing activity and no macrophage activating effects after LPS removal. Anti-adhesion activity towards H. pylori was not found., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The bark of Parkia biglobosa is used in traditional medicine to cure a wide range of illnesses. Polysaccharides were extracted from the bark with 50% ethanol-water, 50°C and 100°C water, and seven active fractions obtained by anion exchange chromatography and gel filtration. The complement fixation and macrophage stimulating activities of the different fractions were determined. The acidic fractions PBEII-I and PBEII-IV were the most active in the complement fixation assay, but the other fractions were also potent compared to the positive control BPII from Biophytum petersianum. Fractions PBEII-I and PBEII-IV were also the most potent fractions in stimulating macrophages to release nitric oxide. Structural studies showed that PBEII-I and PBEII-IV were pectic type polysaccharides, containing arabinogalactan type II structures. The observed differences in biological activities among the seven purified polysaccharide sub-fractions are probably due to differences in monosaccharide compositions, linkage types and molecular sizes., (Copyright © 2013 Elsevier 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.)

The bark of Cola cordifolia used in Malian traditional medicine contains unusual types of polysaccharides with immunomodulating activities. We report for the first time on the structure of a polymer designated CC1P1 having the repeating structure [2→)[α-D-Gal(1→3)]α-L-Rha(1→4)α-d-GalA(1→] as determined by NMR and GC/MS. α-Linked Gal is unusual in pectins. The Mw of 135 kDa was determined by SEC-MALLS. CC1P2 (1400 kDa), another polymer, having the same backbone, but this was substituted with α-4-OMe-GlcA, α-2-OMe-Gal and α-Gal as terminal units. CC1P1 shows a high complement-fixing activity, IC₅₀ being 2.2 times lower than the positive pectin control PMII (IC₅₀ appr. 71 μg/mL) while IC₅₀ of CC1P2 is 1.8 times lower. The simple structure of CC1P1 did not activate macrophages, while CC1P2 (100 μg/mL) showed the same potency as the positive controls PMII (100 μg/mL) and LPS (500 ng/mL). No cytotoxicity was detected., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Environmental change in the Sudan-Sahel region of West Africa (SSWA) has been much debated since the droughts of the 1970s. In this article we assess climate variability and environmental stress in the region. Households in Senegal, Mali, Burkina Faso, Niger, and Nigeria were asked about climatic changes and their perceptions were compared across north-south and west-east rainfall gradients. More than 80% of all households found that rainfall had decreased, especially in the wettest areas. Increases in wind speeds and temperature were perceived by an overall 60-80% of households. Contrary to household perceptions, observed rainfall patterns showed an increasing trend over the past 20 years. However, August rainfall declined, and could therefore potentially explain the contrasting negative household perceptions of rainfall trends. Most households reported degradation of soils, water resources, vegetation, and fauna, but more so in the 500-900 mm zones. Adaptation measures to counter environmental degradation included use of manure, reforestation, soil and water conservation, and protection of fauna and vegetation. The results raise concerns for future environmental management in the region, especially in the 500-900 mm zones and the western part of SSWA.

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.

The study, which received the support of the Development and Co-operation Management of the Swiss Confederation in the frame of the Socio-Sanitary Support Program Mali-Switzerland, proceeded from February to March 2004. The goal was to evaluate the impact of a workshop of formation of the prescribers on the Improved Traditional Phytomedicines (ITP), carried out in October 2001, on the consumption of the ITP in the medical structures of the District of Kadiolo. The study required the data-gathering of consumption, starting from the cards of stock of the years 2001, 2002 and 2003 of the Distributor Warehouse of the Reference Health Center and of the Pharmacies of the Community Health Centers. To evaluate the appreciation of the ITP, the investigations were carried out near the prescribers and the users. The overall consumption of ITP in CSRéf and 16 CSCom of the District knew a progressive increase, while passing from 2 565 480 F CFA in 2001 to 4 307 760 F CFA in 2003. The consumption of ITP during the year 2003 was of 27.83 F CFA per capita. The ITP in general were well appreciated by the prescribers and the consumers. Various projections of the consumption data recorded in Kadiolo allowed considering the potential market of the ITP currently available in Mali with a value ranging between 414 and 560 millions of F CFA.

The Malian medicinal plant Biophytum petersianum Klotzsch (Oxalidaceae) is used as a treatment against various types of illnesses related to the immune system, such as joint pains, inflammations, fever, malaria, and wounds. A pectic polysaccharide obtained from a hot water extract of the aerial parts of B. petersianum has previously been reported to consist of arabinogalactans types I and II (AG-I and AG-II), probably linked to a rhamnogalacturonan backbone. We describe here further structural characteristics of the main polysaccharide fraction (BP1002) and fractions obtained by enzymatic degradations using endo-alpha-d-(1-->4)-polygalacturonase (BP1002-I to IV). The results indicate that in addition to previously reported structures, rhamnogalacturan type II and xylogalacturonan areas appear to be present in the pectic polymer isolated from the plant. Atomic force microscopy confirmed the presence of branched structures, as well as a polydisperse nature. We further tested whether the BP1002 main fraction or the enzymatically degraded products could induce immunomodulating activity through stimulation of subsets of leukocytes. We found that macrophages and dendritic cells were activated by BP1002 fractions, while there was little response of T cells, B cells, and NK cells. The enzymatic treatment of the BP1002 main fraction gave important information on the structure-activity relations. It seems that the presence of rhamnogalacturonan type I is important for the bioactivity, as the bioactivity decreases with the decreased amounts of rhamnose, galactose, and arabinose. The demonstration of bioactivity by the plant extracts might indicate the mechanisms behind the traditional medical use of the plant.

Aim of the Study: The present study is aimed to determine the bioactivity and structure of polysaccharides present in the leaves from the Malian medicinal plant Opilia celtidifolia [Guill. & Perr. Endl. ex Walp (Opiliaceae)]., Materials and Methods: The polysaccharides from the leaves of Opilia celtidifolia were isolated from water extracts of the leaves using gelfiltration and anion exchange chromatography giving the fractions Oc50A1 and Oc50A2. Monosaccharide composition was determined by gas chromatography of the derived TMS-derivatives of the methyl-glycosides. Linkages were determined of the partly methylated, partly acetylated alditol acetates obtained after a process including reduction, methylation, hydrolysis, reduction and acetylation followed by GC-MS. Effects on the complement system and the macrophages were determined using specific methods aimed for studying those activities., Results: The polysaccharide fractions isolated from the leaves of Opilia celtidifolia has high complement fixing activity and induce nitrite oxide release from macrophages in a dose dependent manner. The fractions had an ICH50 of 0.5 and 0.9 microg/ml respectively in the complement fixing assay. They induced the release of 7.2 and 7.3 microM of nitrite oxide from macrophages respectively at a dose of 100 microg/ml. The monosaccharide composition in Oc50A1 and Oc50A2, analysed, showed the presence of arabinose (26.7 and 13.2%), galactose (31.5 and 28%) and galacturonic acid (5.3 and 7.8%) respectively. The Yariv test confirmed the presence of arabinogalactan type II in both fractions. Structural analyses did also show the presence of terminal and 1-4 linked galacturonic acid and terminal and 1-2 linked rhamnose. Endo-polygalacturonanase treatment was performed to isolate the heavily substituted parts of the polysaccharides. These parts contained the same monosaccharides in similar proportion, and showed stronger dose dependent complement fixing activity and also stimulated macrophages to release nitrite oxide., Conclusions: The leaves of Opilia celtidifola contains polysaccharides of pectic type that have both complement fixing and macrophage stimulating activity.

A prospective, dose-escalating, quasi-experimental clinical trial was conducted with a traditional healer using a decoction of Argemone mexicana for the treatment of malaria in Mali. The remedy was prescribed in three regimens: once daily for 3 days (Group A; n=23); twice daily for 7 days (Group B; n=40); and four times daily for the first 4 days followed by twice daily for 3 days (Group C; n=17). Thus, 80 patients were included, of whom 80% were aged<5 years and 25% were aged<1 year. All presented to the traditional healer with symptoms of malaria and had a Plasmodium falciparum parasitaemia>2000/microl but no signs of severe malaria. The proportions of adequate clinical response (ACR) at Day 14 were 35%, 73% and 65% in Groups A, B and C, respectively (P=0.011). At Day 14, overall proportions of ACR were lower in children aged<1 year (45%) and higher in patients aged>5 years (81%) (P=0.027). Very few patients had complete parasite clearance, but at Day 14, 67% of patients with ACR had a parasitaemia<2000/microl. No patient needed referral for severe disease. Only minor side effects were observed. Further research should determine whether this local resource could represent a first-aid home treatment in remote areas.

The aim of this paper was to further elucidate the structure and the immunomodulating properties of the pectic polymer GOA2, previously isolated from Glinus oppositifolius. Enzymatic treatment of GOA2 by endo-alpha-d-(1 --> 4)-polygalacturonase led to the isolation of three pectic subunits, GOA2-I, GOA2-II, and GOA2-III, in addition to oligogalacturonides. GOA2-I was shown to consist of 1,2-linked Rhap and 1,4-linked GalpA in an approximately 1:1 ratio, and NMR-analysis showed that the monomers were linked together in a strictly alternating manner. The galactose units in GOA2-I were found as terminal-, 1,3-, 1,6-, 1,4-, 1,3,4-, and 1,3,6-linked residues, while the arabinofuranosyl existed mainly as terminal- and 1,5-linked units. A rhamnogalacturonan-I type structure was suggested being the predominant part of GOA2-I. According to linkage analysis GOA2-II and GOA2-III contained glycosidic linkages characteristic for rhamnogalacturonan-II type structures. GOA2 was shown by sedimentation velocity in the analytical ultracentrifuge, to have a broad degree of polydispersity with a mode s(20,w) value of approximately 1.9 S, results reinforced by atomic force microscopy measurements. The polydispersity, as manifested by the proportion of material with s(20,w) > 3 S, decreased significantly with enzyme treatment. The abilities of GOA2, GOA2-I, GOA2-II, and GOA2-III to induce the proliferation of B cells, and to exhibit complement fixing activities were tested. In both test systems, GOA2-I showed significantly greater effects compared to its native pectin GOA2. GOA2-I was in addition shown to exhibit a more potent intestinal immune stimulating activity compared to GOA2. The ability of GOA2 to induce secretion of proinflammatory cytokines was examined. Marked upregulations in mRNA for IL-1beta from rat macrophages and IFN-gamma from NK cells were found.

In material-resource poor countries like Mali, traditional practices incorporate the use of plants for medicinal purposes. Ethnobotanical research has documented traditional uses of plants, while concomitant studies by natural product chemists, ethnobotanists, and microbiologists have verified the efficacy of using traditional medicinal plants that have proven antimicrobial activity. These plants may also be used to protect agricultural crops pre-harvest and post-harvest from insect herbivory. In Mali, subsistence farmers, regional scientists, and extension specialists rely on local plants for many medicinal needs and are amenable to using traditional plant materials for insect pest management. The goal of this research was to develop Integrated Pest Management (IPM) strategies using Malian traditional medicine as a discovery lead. The discovery premise was based on identifying plants through a matrix approach utilizing agricultural scientists, traditional practitioners, and subsistence farmers. We hypothesized that plants used in traditional medicine with antimicrobial activity lead to potential insect pest management agents. To test our hypothesis, we developed a four-step process for selecting Malian plant species. Seven criteria were selected to create a systematic matrix to identify the most promising plant materials for practical, affordable, ecologically-sound insect management by Malian farmers. In the first step of the process, we developed a list of 294 medicinal Malian plant species which were evaluated using the matrix. Sixty-seven plant species met our main criteria. After the environmental soundness of these species was evaluated using four minor criteria, 50 species emerged from this pre-chemical, pre-bioassay process for further consideration in IPM programs in Mali.

Sixty-four extracts issued from twenty-one plants used in the Malian traditional medicine--several of them as antiparasitic drugs--were assayed for their antileishmanial effects against both extracellular and intracellular forms of Leishmania major. Seven extracts from six different plants--Sarcocephalus latifolius, Zanthoxylum zanthoxyloides, Entada africana, Bobgunnia madagascarensis, Pseudocedrela kotschyi and Psorospermum guineense--were found to be significantly active against the intracellular form of the parasite.

The survey has been carried out in the context of the project "Traditional Practices and Primary Health Care", developed by the Traditional Medicine Department (DMT) of the INRSP and the Swiss Ngo Antenna Technologies, with the support of Aidemet Ngo. The objective was to evaluate the knowledge, attitudes and practices of traditional healers on uncomplicated and severe malaria, in the perspective of collaboration between traditional and modern medicine for the optimal care of the critical cases. The investigation has been conducted from January to February 2003 in the health areas of Kendié (Bandiagara District, Mopti Region) and Finkolo (Sikasso District and Region). The interviews concerned in total 79 traditional healers, 9 of which were women. The survey showed that the traditional healers have a good knowledge of the symptomatology of uncomplicated and severe malaria, and their diagnosis corresponds with that of the health workers who do not have access to laboratory analyses. On the other hand, the traditional etiology doesn't always correspond with the modern one, even if the traditional healers mention, among the causes of malaria, the mosquito bites. Most treatments were based on plant substances. We identified 66 medicinal species in total. The majority of them had already been studied for anti-plasmodial activity. We therefore investigated 8 of these plants, which had not previously been thoroughly studied. Extracts of different parts of these plants were tested on standard chloroquine-resistant strains of Plasmodium falciparum; the most active plants were Argemone mexicana, Securinega virosa, Spondias mombin and Opilia celtidifolia, with IC50 ranging from 1.00 to 4.01 microg/ml.

Extracts form 10 different Malian medicinal plants with a traditional use against schistosomiasis were investigated for their possible content of proteolytic activity. The proteolytic activity was studied by measuring the hydrolysis of two synthetic peptide substrates Z-Ala-Ala-Asn-NHMec and Z-Phe-Arg-NHMec. Legumain- and papain-like activities were found in all tested crude extracts except those from Entada africana, with the papain-like activity being the strongest. Cissus quadrangularis, Securidaca longepedunculata and Stylosanthes erecta extracts showed high proteolytic activities towards both substrates. After gel filtration the proteolytic activity towards the substrate Z-Ala-Ala-Asn-NHMec in root extract of Securidaca longepedunculata appeared to have Mr of 30 and 97kDa, while the activity in extracts from Cissus quadrangularis was at 39kDa. Enzymatic activity cleaving the substrate Z-Phe-Arg-NHMec showed apparent Mr of 97 and 26kDa in extracts from roots and leaves of Securidaca longepedunculata, while in Cissus quadrangularis extracts the activity eluted at 39 and 20kDa, with the highest activity in the latter. All Z-Phe-Arg-NHMec activities were inhibited by E-64 but unaffected by PMSF. The legumain activity was unaffected by E-64 and PMSF. The SDS-PAGE analysis exhibited five distinct gelatinolytic bands for Cissus quadrangularis extracts (115, 59, 31, 22 and 20kDa), while two bands (59 and 30kDa) were detected in Securidaca longepedunculata extracts. The inhibition profile of the gelatinolytic bands and that of the hydrolysis of the synthetic substrates indicate the cysteine protease class of the proteolytic activities. Several cysteine protease activities with different molecular weights along with a strong variability of these activities between species as well as between plant parts from the same species were observed.

Use of official health services often remains low despite great efforts to improve quality of care. Are informal treatments responsible for keeping a number of patients away from standard care, and if so, why? Through a questionnaire survey with proportional cluster samples, we studied the case histories of 952 children in Bandiagara and Sikasso areas of Mali. Most children with reported uncomplicated malaria were first treated at home (87%) with modern medicines alone (40%), a mixture of modern and traditional treatments (33%), or traditional treatment alone (27%). For severe episodes (224 cases), a traditional treatment alone was used in 50% of the cases. Clinical recovery after uncomplicated malaria was above 98% with any type of treatment. For presumed severe malaria, the global mortality rate was 17%; it was not correlated with the type of treatment used (traditional or modern, at home or elsewhere). In the study areas, informal treatments divert a high proportion of patients away from official health services. Patients' experience that outcome after standard therapeutic itineraries is not better than after alternative care may help to explain low use of official health services. We need to study whether some traditional treatments available in remote villages should be considered real, recommendable first aid.

In Mali the use of traditional medicine is a wide spread phenomenon, not only because of its cultural importance, but also as the majority of people cannot afford the western drugs or medicines. In Mali, the Office du Niger area constitutes the main zone of schistosomiasis transmission where both Schistosoma mansoni and Schistosoma haematobium are encountered. An ethnopharmacological survey, using questionnaire, was conducted in the Office du Niger area of the Niono District to determine the plants used against schistosomiasis amongst traditional healers. Forty healers from 21 villages of six different health areas were interviewed. All interviewed healers knew about urinary schistosomiasis, while only six knew about the intestinal form. The presence of blood in urine was reported as the main symptom of urinary schistosomiasis. Fifty-five plants belonging to 30 families were reported to be used alone for treating urinary and intestinal schistosomiasis, while nine combinations of plants were used against the urinary form of the disease. Cissus quadrangularis and Stylosanthes erecta were the plants most frequently used and were reported for the first time, to be used against schistosomiasis in Mali.

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.

Water, methanol and dichloromethane extracts prepared from various parts of 40 medicinal plant species from Mali were investigated for their trypanocidal activity against Trypanosoma brucei brucei. Of a total of 165 extracts tested in vitro in the Low Inoculation Long Incubation Test (LILIT), 24 extracts showed a high trypanocidal activity. Using the Long-Term Viability Assay (LtVA) for corroboration of the results of the 24 extracts, it was found that 15 samples had minimum inhibitory concentration (MIC) values > 10 microg/ml, eight MIC values of 100 microg/ml and one MIC values of 50-100 microg/ml. So far, four extracts with MIC values < or = 100 microg/ml were tested for antitrypanosomal activity in mice, experimentally infected with Trypanosoma brucei brucei. Only, the aqueous extracts of the leaves of Terminalia avicennioides Guill. and Perr. (Combretaceae) and the stem bark of Ceiba pentandra (L.) Gaertn. (Bombacaceae) were able to reduce the parasitaemia in animals treated at the dose of 100 mg/kg b.w. (intraperitoneally, two times daily for 3 days) and of 150 mg/kg b.w. (per os, two times daily for 3 days), respectively. The reduction of parasitaemia was, however, statistically significant (p=0.002) only in case of treatment with Terminalia avicennioides.

Structures of three pectic arabinogalactans, one from Vernonia kotschyana (Vk2a) and two from Cochlospermum tinctorium (Ct50A1 and Ct50A2), and their complement fixation and induction of B cell proliferation in vitro were compared. The polysaccharide Vk2a expressed potent biological activity in both assays compared with Ct50A1 and Ct50A2. Vk2a possessed a very high molecular weight (1150 +/- 20 kDa) compared with Ct50A1 and Ct50A2 which both showed a polydisperse nature with the highest molecular weight polymers in each fraction estimated at approximately 105 kDa (Ct1a) and 640 +/- 100 kDa (Ct2a), respectively. The HMW polymers showed complement fixation in the same range as the native fractions. The arabinogalactan II content was low in Vk2a (2%) compared with that in Ct50A1 (23%) and Ct50A2 (12%). The high molecular weight polymers were subjected to digestion with a beta-d-(1, 3)-galactanase-rich fraction from Driselase, oligomers were isolated by HPAEC, and their finer structures were determined by MALDI- and ES-qoToF-MS, linkage, and monosaccharide composition analyses. Vk2a consists of both a galacturonan core and a rhamnogalacturonan core rich in neutral side chains. The backbones of both Ct-polysaccharides consist mainly of RG-I regions with numerous neutral side chains dominated by galactosyl residues, whereas the homogalacturonan regions seem to be small. Differences in the chain lengths of the 6-linked galacto-oligosaccharides attached to the 3-linked galactan core could not be related to the differences in the potencies of the biological activities observed.

Biophytum petersianum Klotzsch (syn. Biophytum sensitivum (L.) DC) is a medicinal plant having a traditional use, among others, as a wound healing remedy in Mali and other countries. As a water extract of the aerial parts of the plant is a frequently used preparation, we decided to look for a bioactive polysaccharide in this extract. One of the obtained polysaccharide fractions, BP100 III, isolated from a 100 degrees C water extract from the aerial parts of B. petersianum and having a monosaccharide composition typical for pectic substances, was shown to exhibit potent dose-dependent complement fixating activity. The BP100 III fraction was subjected to degradation by endo-alpha-d-(1-->4)-polygalacturonase, and three fractions were obtained by gel filtration. The highest molecular weight fraction, BP100 III.1, had a more potent activity in the complement test system than the native polymer, while the two lower molecular weight fractions were less active than the native polymer. The major part of BP100 III.1 consists of galacturonic acid and rhamnose, with branches being present on both the rhamnose and galacturonic acid residues. Arabinogalactan type II is also present in the polymer, indicating that BP100 III.1 has a structure typical of the hairy region of pectins. The major part of the two other fractions is a galacturonan, containing a strikingly high number of branch points, some to which xylose is attached. These results indicate that the pectic substance in B. petersianum contains both rhamnogalacturonan and xylogalacturonan regions.

Glinus oppositifolius (L.) Aug. DC. (Aizoaceae) is a Malian medicinal plant used against various types of illnesses related to the immune response, like joint pains, inflammations, fever, malaria and wounds. Two pectin type polysaccharides, GOA1 and GOA2, being isolated from a 50 degrees C water extract from the aerial parts of Glinus oppositifolius were investigated for their activity towards the complement system and different leukocyte subsets because of the assumed effects on conditions related to the immune system. The polysaccharide polymer in GOA1 was shown to contain considerable amounts of the neutral sugars arabinose (26.4 mol%) and galactose (42.9 mol%), and methylation analysis indicated the presence of arabinogalactans type I (AG-I) and type II (AG-II). GOA2 was rich in galacturonic acid (68.3 mol%), along with rhamnose, arabinose and galactose. Structural studies indicated that rhamnose and galacturonic acid might constitute a rhamnogalacturonan backbone, often found in pectic substances, with side chains consisting of arabinose and galactose. Both GOA1 and GOA2 were shown to exhibit potent dose-dependent complement fixating activities, and induced chemotaxis of macrophages, T cells and NK cells.

Structure and immunological characteristics of the pectic arabinogalactan Vk2a (previously reported as Vk100A2a) from the roots of Vernonia kotschyana Sch. Bip. ex Walp. were investigated after enzymatic digestion of the galacturonan moiety and the side chains of the rhamnogalacturonan structure of Vk2a. endo-alpha-D-(1-->4)-Polygalacturonase digestion released the high molecular weight 'hairy region' (Vk2a-HR) and oligogalacturonides. Vk2a-HR consisted of GalA (4-linked) and Rha (2- or 2,4-linked) in a 1:1 ratio, with 60% of Rha branched at C-4. The Rha located in the rhamnogalacturonan core was branched randomly by Gal units. Vk2a-HR was rich in neutral sugars such as Araf 5- (12.2%) and 3,5-substituted (12.8%) and terminally- (14.1%) linked and Gal 4- (13.0%), 3- (0.9%), 6- (2.2%) and 3,6- (1.1%) substituted. Arabinans with chain lengths up to 11 units were identified. Araf residues were attached to C-3 of alpha-L-(1-->5)-Araf chains and to C-4 of Gal residues. Single Gal units and chains of beta-D-(1-->6)-linked galacto di- to penta-saccharides were attached to a beta-D-(1-->3)-galactan core. All the enzyme resistant fractions expressed potent complement fixation and induction of B-cell mitogenic activity, and the present study indicates that there may be several and possibly structurally different active sites involved in the bioactivity of Vk2a. The bioactive sites may be located both in the more peripheral parts of the molecule but also in the inner core of the 'hairy region' or in larger enzyme-resistant chains.

Two polysaccharides, a pectin (Vk100A2b) and a pectic arabinogalactan (Vk100A2a) with mean Mw 2 x 10(4) and 1.15 x 10(6)Da, respectively, were isolated from the dried powdered roots of Vernonia kotschyana Sch. Bip. ex Walp. by hot water extraction followed by fractionation on DEAE-Sepharose fast flow and Sephacryl S-400 HR. The pectin showed low-complement fixation activity and no influence on proliferation of B or T cells, while the pectic arabinogalactan showed a potent, dose-dependent complement fixation activity and a T cell independent induction of B-cell proliferation. Both polysaccharides induced chemotaxis of human macrophages, T cells and NK cells. exo-alpha-L-arabinofuranosidase and exo-beta-D-galactosidase digestion followed by component sugar and methylation analysis indicated that Vk100A2a consisted of a highly branched rhamnogalacturonan core with approximately 50% of the rhamnose 1,2,4-substituted, side chains rich in terminal-, 1,5-linked and 1,3,5-branched arabinose and terminal-, 1,4-, 1,6-linked and 1,3,6-branched galactose. The enzyme resistant part of Vk100A2a still showed strong complement fixating activity, suggesting that this activity may at least in part be expressed by carbohydrate structures present in the enzyme resistant, inner portion of the polymer.

Bioassay-directed fractionation of an anti-inflammatory CHCl(3)-MeOH (9:1) extract of leaves of Vernonia colorata, using a carrageenan-induced rat paw model, led to the isolation of six new compounds (1-6). These were assigned as two new androst-8-en glycosides, 3-O-[beta-d-galactopyranosyl-(1-2)-[beta-d-glucopyranosyl-(1-->6)]-beta-d-glucopyranoside]-5alpha,14alpha-androst-8-ene (1) and 3-O-[beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranoside]-5alpha,14alpha-androst-8-ene (2), two new stigmastane-type glycosides, 3beta,21,24-trihydroxy-21,23;22,28;26,28-triepoxy-5alpha-stigmasta-8(9),14(15)-dien-3-O-beta-d-galactopyranosyl-(1-->2)-beta-d-glucopyranoside (3) and 3beta,21,24-trihydroxy-21,23;22,28;26,28-triepoxy-5alpha-stigmasta-8(9),14(15)-dien-3-O-beta-d-galactopyranosyl-(1-->2)-beta-d-(6-acetyl)glucopyranoside (4), and two new stigmastane-type steroids, 3beta,25,29-trihydroxy-5alpha-stigmasta-8(9),14(15),24Z(28)-triene (5) and 3beta,23,25-trihydroxy-24,28-epoxy-5alpha-stigmasta-8(9),14(15)-diene (6). The structures of 1-6 were elucidated by spectral and chemical studies. Compounds 1-6 were tested for the anti-inflammatory activity, but all were inactive or weakly inactive as anti-inflammatory agents.