Lupenyl Acetate Research Articles

Economic analysis of the supercritical fluid extraction of lupane-triterpenoids from Acacia dealbata Link bark

The supercritical fluid extraction of Acacia dealbata Link. bark was performed with carbon dioxide at different pressures (10–30 MPa), temperatures (40–80 °C), and cosolvents contents (0–10 wt% of ethyl acetate or ethanol) to analyse their effect on various performance indicators whose best values were: total extraction yield of 1.57 wt%; lupenyl acetate (LA) and lupenone (Lu) extraction yields of 777.5 mg kgbark-1 and 679.8 mg kgbark-1; and LA and Lu extract concentrations of 15.8 wt% and 12.8 wt%. Two extraction curves were measured, and an economic analysis was accomplished. The impact of pressure, temperature, cosolvent content, and extraction time on the cost of manufacturing (COM) and productivity were evaluated, reaching a minimum of 52.3 € kgextract-1. A sensitivity analysis showed that the electricity price is the most impactful variable on the COM. Overall, the increase of pressure, temperature and cosolvents content favoured the productivity, decreasing the production cost.

Allelopathic Activity of Canadian Goldenrod (Solidago canadensis L.) Extracts on Seed Germination and Growth of Lettuce (Lactuca sativa L.) and Garden Pepper Cress (Lepidium sativum L.).

Native to N. America, Canadian goldenrod (Solidago canadensis L.) was introduced to Europe as an ornamental plant and quickly spread here and in other parts of the world. The rapid spread of the plant is due to several reasons: phenotypic plasticity, broad climatic tolerance, propagation via underground rhizomes and seeds that mature in large numbers, etc. Additionally, the success of Canadian goldenrod's invasion is determined by its allelochemicals that affect seed germination, root formation and whole growth of nearby plants. Allelopathy of various extracts and essential oils (EOs) of S. canadensis on seed germination and growth of lettuce (Lactuca sativa L.) and garden pepper cress (Lepidium sativum L.) was evaluated and compared with other Solidago species (S. virgaurea, S. × niederederi) collected from the same growing locality in Lithuania. Soil characteristics (conductivity, pH and major elements) of the collecting site were determined. Aqueous flower extracts of all studied Solidago species showed the highest inhibitory effect on model plants. Canadian goldenrod leaf water/diethyl ether extract showed highest inhibitory effect in all relative concentrations (1.0; 0.1; 0.01) suppressing growth of L. sativa (from 0 to 2.3 mm compared with 22.7 mm for control samples) and L. sativum (from 0.5 to 16.8 mm compared with 35.3 mm in control). It was noticed that garden pepper cress was more susceptible to Solidago spp. inhibitory effects than lettuce. S. canadensis root EOs comprised mainly of limonene (35.0%) and β-pinene (26.2%) and inflorescence oils containing α-pinene (21.6%), germacrene D (15.1%), limonene (10.2%) and lupenyl acetate (9.8%) exhibited the highest inhibitory effect on lettuce and garden pepper cress growth. Relative germination and vigor index of model plants was conducted. Chemical composition of extracts and EOs was determined by HPLC/DAD/TOF and GC/MS techniques.

In Vitro Anticancer Activity on 3T3, PC3, and HeLa Cell Line and GC-MS Assay of Oil Fractions of Alstonia Scholaris Flower Obtained by Column Chromatography

Several plant-derived compounds are currently successfully employed in cancer treatment. Various studies have demonstrated the anticancer or cytotoxic potential of different extracts of Alstonia scholaris at the highest doses. This study aimed to analyze the anticancer potential of oil fractions obtained from Alstonia scholaris flower isolation. The oil fractions were characterized using gas chromatography–mass spectrometry (GC-MS) assay. The (3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyl-tetrazolium bromide) (MTT) colorimetric assay was used for 3T3, PC3, and HeLa cell line cytotoxic potential of oil fractions. The results showed no cytotoxic activity of oil fractions, i.e., Oil I and Oil II were at a minimum dose of 30 μg/ml. However, the GC-MS assay depicted saturated (palmitic acid, ethyl ester, caproic acid, stearic acid, ethyl ester, octacosanoic acid, etc.), unsaturated (oleic acid, 3-(octadecyloxy)propyl ester, ethyl oleate and some other hydrocarbons such as betulin, ethyl iso-allocholate, lupenyl acetate, phthalic anhydride, phytol, etc. Thus, the reported chemical constituents showed no significant anticancer effect in the scientific literature. This research suggested that Alstonia has no potential as an anticancer agent. The findings of this study provide insight into maintaining the optimum data for future aspects of plant-derived phytoconstituents with potential cytotoxic effects on 3T3, PC3, and HeLa cell lines.

Molecular Docking Analysis of Ficus religiosa Active Compound with Anti-Inflammatory Activity by Targeting Tumour Necrosis Factor Alpha and Vascular Endothelial Growth Factor Receptor in Diabetic Wound Healing

BACKGROUND: Diabetes mellitus contributes to the delayed healing of wounds causes disturbance of inflammatory cytokine. Tumour necrosis factor alpha (TNF-alpha) and Vascular Endothelial Growth Factor Receptor (VEGFR) both have a role in the persistent inflammation associated with diabetic wounds. Ficus religiosa has developed a reputation as a traditional wound healer among some java people in Indonesia. AIM: Our study aims to discover the molecular interaction between the active constituents of F. religiosa with TNF-alpha and VEGFR. MATERIALS AND METHODS: This research was conducted in computerized molecular docking using Protein database, Pymol, Discovery studio, and Pyrex software. A thorough literature search was conducted to identify the potential compound and molecular target for diabetic wounds. Analysis of its anti-inflammatory properties was also carried out using a passonline webserver. Pharmacokinetic analysis was performed using the Lipinski Rule of Five websites and the PreADMET website. RESULTS: Each of the study’s active compounds has a good pharmacokinetic profile. The predictions of the compound’s structure indicate that it has a strong anti-inflammatory impact. Lupenyl acetate and Lanosterol bind more strongly to the TNF-alpha than the natural ligand, but Piperine binds more strongly to VEGFR. CONCLUSIONS: Lupenyl acetate, Lanosterol, and Piperine compounds have anti-inflammatory effects through inhibition of TNF-alpha and VEGFR. In addition, this compound has potential to become a drug because it has good pharmacokinetics. Future studies are required to determine the effectiveness and toxicity of Lupenyl acetate, Lanosterol, and Piperine as potential treatment in diabetic wounds.

Lupane-type triterpenoids from Acacia dealbata bark extracted by different methods

The management of invasive species generates large amounts of biomass which end up in low value applications. However, these residues can potentially contain compounds with important bioactive properties. In this study the bark of Acacia dealbata Link (Fabaceae) was extracted by different methods targeting triterpenoids content and bulk product. Batch solid-liquid extraction (SLE-batch), Soxhlet extraction (n-hexane, dichloromethane, ethyl acetate and ethanol) and supercritical fluid extraction (SFE) (CO2 with/without ethanol or ethyl acetate) were performed under different pressure and/or temperature conditions in order to assess total extraction yield (ηTotal), extract concentrations and yields of lupenyl acetate and lupenone. The extracts composition was analysed by gas chromatography coupled to mass spectroscopy. Summarily: (i) the highest values of ηTotal were achieved with ethanol by both Soxhlet and SLE-batch, and by SFE at 300 bar, 80 ⁰C with 5 wt.% ethanol; (ii) the highest concentrations of triterpenoids were obtained with n-hexane by Soxhlet and SLE-batch and, and by SFE at 200 bar, 40 °C with 5 wt.% ethyl acetate; (iii) the maximum individual yields were achieved with ethanol by both Soxhlet and SLE-batch, and by SFE at 200 bar, 40 °C with 5 wt.% ethyl acetate. The solubilities of lupenyl acetate, lupenone, tetracosanoic acid and hexacosan-1-ol in the various solvents were theoretically estimated, providing important insights for the interpretation of the experimental results.

An In-silico and In-vitro Comparative Study of Compounds from Phoenix sylvestris Roxb. For Alpha-Amylase Enzyme Inhibition Involved in Diabetes Mellitus

Identification of potential phytocompound from Phoenix sylvestris RoxB. For anti-diabetic potential and its validation through computational methods. Partially purified fraction evaluated for Alpha-amylase enzyme inhibition and GC-MS identified fraction validated compounds for potential anti-diabetic activity by Auto docking method. The phytocompounds investigation revealed maximum abundance of total phenol (31.55±0.55 μg/mg equivalent to Gallic acid) and flavonoid (52.90±0.08 μg/mg equivalent to quercetin) content in ethyl acetate extract. Ethyl acetate extract interestingly showed maximum alpha-amylase inhibition (71.15 %, IC50- 98.50±0.10 μg/ml), which was a mixed type of inhibition as compared to acarbose (78.64%, IC50- 88.61±0.50 μg/ml), which showed a competitive type of inhibition analyzed by Line weaver-Burk double reciprocal plot versus 1/v and 1/s. The docking study illustrated that Lupenyl acetate compound was the most active compound that showed maximum binding free energy (-7.16 Kcal/mol) and interacted with the Val64, Asn88, Gly90, Asn87, Arg87, Arg10, Gly9, Gln7, Gln5, Thr5, Trp221, Phe222, Asn5, Pro223, Ser3, Ser226, Lys227 and Gly225 amino acid residues which inhibited the alpha-amylase more efficiently than acarbose (binding energy -4.71 Kcal/mol). The present study concluded that the components of ethyl acetate extract had Alpha enzyme inhibition with reducing potential, and it may be due to the synergistic effect. The study suggested ethyl acetate extract as a natural promising therapeutic compound for the treatment of diabetes.

The study of Calotropis Gigantea leaf metabolites from Ie Brouk geothermal area Lamteuba-Aceh Besar using molecular docking

Analysis of Analysis of the metabolite contents of C. gigantea leaf from the Ie Brouk geothermal area has been done. The metabolites were determined by Gas Chromatography Mass Spectrometry and proteins from Main Protease (6LU7) and Spike Glycoprotein (6VXX) was studied by molecular docking. The leaf sample was prepared by extraction procedure using 96% ethanol solvent. The yield obtained was analyzed by using Gas Chromatography Mass Spectrometry. Molecular docking between metabolite and proteins showed strong interactions from Urs-12-en-24-oic acid 3-oxo methyl ester, Lupenyl Acetate, Beta Amyrenyl Acetate with high binding affinity of -15.1, -14.3, and -14.1 kcal/mole to 6VXX, and -12.3, -11.1, and -11.6 kcal/mole to 6LU7, respectively. The visualization of the interaction between metabolite to an amino acid proteins showed well pocket number. The pocket number in 6LU7 were higher than 6VXX, which was contributed from a compact state structure of 6VXX. The results showed that the ethanol extract of C. gigantea from the Ie Brouk geothermal area has an enormous potential to be further developed.

Phytochemical Composition and Biological Activities of Wild Scolymus maculatus L.

Background: The wild population of spotted golden thistle, Scolymus maculatus, which belongs to the Compositae family, is believed to be one of the multi-curative wild plants mentioned in Flora Palaestina. This study aims to disclose the phytochemical composition, antioxidant potential, and antimicrobial activity of wild S. maculatus collected from the farms of Kabul, a village in northwest Galilee, for the first time. Methods: The phytochemical components of crude S. maculatus extracts from methanol, ethyl acetate, and n-hexane solvents were separated and identified using gas chromatography-mass spectrometry (GC-MS) in the electron impact (EI) mode. The free radical scavenging of the plant extracts was measured by DPPH assay. The microdilution test was used to determine the minimum inhibitory concentrations (MICs) of different S. maculatus extracts and to evaluate their antimicrobial activities. Results: Thirty-two phytochemicals were found in S. maculatus extracts including stigmasterol, γ-sitosterol, lupeol, lupeol acetate, and β-amyrin. Phytochemicals, such as 2-linoleoylglycerol, γ-sitosterol, β-amyrin, lupeol, (3α)-12-oleanen-3-yl acetate, and lupenyl acetate, were found to dominate the methanol extract. Most of these compounds were also observed in ethyl acetate and n-hexane extracts, but at different levels, in addition to some other minor compounds. The various extracts were investigated for their antioxidant and antimicrobial activity. The ethanolic and the methanolic extracts were shown to exhibit the highest free radical scavenging by DPPH assay with a half-maximally effective concentration (EC50) of 0.37 and 0.65 mg/mL respectively, while the other three extracts (aqueous, ethyl acetate and n-hexane) were less active and their EC50 (effective concentration at which DPPH radical was scavenged by 50%) were above 1.0 mg/mL. Moreover, MICs were determined to be effective against Staphylococcus aureus, Salmonella typhimurium, and Candida albicans microorganisms. Ethyl acetate and the ethanolic extracts are active against the three types of microorganisms at a minimum inhibitory concentration (MIC) of 0.5 mg/mL, while aqueous and the n-hexane extracts are inactive against Salmonella typhimurium. Conclusions: The results show that S. maculatus extracts are a rich source of compounds that can play an important role in human health, and in a broader context, in the treatment of various diseases, such antimicrobial and antioxidant-related ailments.

Secondary metabolite Constituents, Antimicrobial Activity and Gas chromatography-Mass spectroscopy Profile of Bombax buonopozense P. Beauv.(Bombacaceae) Stem bark Extract

This study evaluated the phytochemical constituents, antimicrobial activity and structural characteristics using GC-MS of bioactive constituents from the stem bark extract of Bombax buonopozense. Secondary metabolite constituents was assayed using standard procedures. The antimicrobial activity was carried out using agar diffusion method to determine the susceptibility of these microorganisms: (Staphylococcus aureus (ATCC 29213), Streptococcus faecials, Bacillus subtilis (ATCC 8263), Escherichia coli (ATCC 25922), Salmonella tiphi, Pseudomonas aeruginosa (ATCC 27853), Candida albican (ATCC 90029), Aspergillusniger and Phytophera megakarya. EtOAc fraction was chromatographed on silica column to afford oil isolate and its chemical structures were proven with the employment of GC-MS. Phytochemical screening revealed the presence of saponins, flavonoids, reducing sugars, steroids, terpenoids, anthraquinone, phenols and alkaloids. The antimicrobial sensitivity test showed higher activity on Candida albican, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus, moderate to little activity on the rest organisms. The GC-MS of the stem bark oil extract revealed the main constituents as: 1, 2 Benzenedicarboxylic acid 4.10%, Diisobutyl phthalate 1.18%, Dibutyl phthalate 0.72%, Lupenone 0.62%, Lupeol 4.93%, Lupenyl acetate 86.28%, Testosterone decanoate 0.87% and 3-O-Acetyl-6-methylcycloartenol 0.67%. The findings indicate stem bark extract has bioactive compounds which may be effective in the treatment of infection diseases.

Chemical Composition and Cytotoxic Activity of Methanol Extract and its Fractions of Streblus asper Leaves on Human Cancer Cell Lines.

Background:Streblus asper, family Moraceae is well-known important medicinal plant used in the Indian system of medicine. In Ayurveda, stem bark of S. asper is recommended against elephantiasis for which there is still no any other effective medicine in the modern system of medicine.Objectives:In the present work, methanol extract (SAM) and its fractions of S. asper leave tested for in vitro anticancer activity against cancer cell lines (MCF-7, A-549, Hep-G2, and K-562) which claims its folklore importance in cancer and gas chromatography-mass spectrometry identification of extracts was also performed.Materials and Methods:Shade dried plant material was extracted with methanol and fractionated sequentially with hexane, chloroform, and butanol.Results:All tested extracts found highly effective against human lung cancer cell line (A-549) with IC50 <10 μg/mL. On Hep-G2 cancer cell line, only chloroform fraction are highly active with IC50 <10 μg/mL. Methanol and hexane fraction showed potent anticancer activity on K-562 cancer cell line with IC50 <10 μg/mL.Conclusion:Qualitative phytochemical analysis confirmed the presence of fatty acids, phytosterol, triterpenoids, polyol, sugar acid, aldehyde, diterpene, terpene, carboxylic compounds, acid and sugar in S. asper leaves extract. Topmost abundant compounds in SAM are α-D-glucopyranoside (10.60%), glycerol (7.96%), myo-inositol (4.90%), and butanedioic acid (3.30%). Hexane consists of the higher amount of hexadecanoic acid (18.07%), octadecanoic acid (7.39%), β-sitosterol (4.50%), and α-D-glucopyranoside (4.03%). Higher component in chloroform extract is lupenyl acetate (11.25%).SUMMARY All extracts of Streblus asper found potential anticancer activity against lung cancer cell line (A-549)Chloroform fraction is highly active on hepatoma cancer cell line (Hep-G2) whereas methanolic, and hexane fractions have highly cytotoxic potency against leukemia cancer cell line (K-562)Methanolic extract of S. asper is rich source of glycosides, fatty acids, and phytosterolIn Gas chromatography-mass spectrometry evaluation of S. asper β-stigmasterol, β-sitosterol, lycopene, and lupeol identified as an anticancer agent from previously reported literature. Abbreviations used: SRB: Sulforhodamine B assay; SAM: Methanol extract; SAH: Hexane extract; SAC: Chloroform extract.

The Oils from Stems, Leaves and Roots of Elephantopus scaber Linn.

The oil from stems, leaves and roots of Elephantopus scaber Linn. were extracted by solvent macerationtechnique. The percentage yield oil from stems, leaves and roots are 0.001%, 0.003% and 0.04%, respectively.The stem oil gives major constituents of pentacosane (12.3%), lupenyl acetate (11.7%) and fern-7-en-3β-ol(11.0%), while the leaf oil contains isooctyl phthalate (19.2%), hexadecanoic acid (15.0%) and α-linolenic acid(5.0%) as the major components. The major constituents identified in the root oil are hemellitol (11.6%), octylphthalate (6.0%), 1-nonadecanol (5.6%) and 1-octadecanol (5.5%). There were only three compounds detectedand identified in all three parts of the plant, namely decanedioic acid, bis-(2-ethylhexyl)ester, dotriacontane andpentacosane. The oils were analysed by gas chromatography-mass spectrometer and the compounds wereidentified by comparison with the mass spectral fragmentation pattern database.

Studies on chemical constituents from Psychotria straminea

The chemical consituents from Psychotria straminea were separated and purified by column chromatographies on silica gel, Sephadex LH-20, ODS and RP-HPLC. The strictures of the isolated compounds were identified on the basis of physicochemical properties and spectroscopic analysis, as well as comparisons with the data in literature. Sixteen compounds were isolated and elucidated as tectochrysin (1), apigenin (2), kaempferol (3), luteolin (4), diosmetin (5), quercetin (6), kaempferol-4'-O-methylether (7), rhamnetin (8), 7-hydroxycoumarin (9), 7-methoxycoumarin (10), scopoletin (11), lupeol (12), 30-oxo-lupeol (13), lupenyl acetate (14), α-amyrin (15), and ursolic acid (16). This is the first study on the chemical composition of P. Straminea, and all compounds were isolated from P. straminea for the first time. In addition to compounds 6 and 9, the other compounds were isolated from the genus Psychotria for the first time.

Evaluation of nigerian ethnomedical plants for anti-infective and antidiabetic properties

There is need for more scientific justifications for many African plants used ethnomedically in treating infections and diabetes. Extracts and ashes of some of them were evaluated for these activities using standard methods while their active constituents were identified using spectroscopy. Leaves of Jatropha tanjorensis, Eugenia uniflora, Bauhinia monandra, Stachytarpheta cayennensis, Gongronema latifolium stem and root, and Clausena lansium stem bark had antihyperglycaemic actions that were due to insulin release. Insulin stimulation was reported as an unreported mechanism of their actions. Insulinotropic quercetin, isoverbascoside, 1:1 mixture of α- and β-amyrin cinnamates, and chalepin and imperatorin were the active constituents of the last four plants. HPLC confirmed their relative proportions in the active fractions, while synergism in some of the constituents and active fractions were also observed. Rutin from B. monandra was a pro-drug. Murraya koenigii was slow acting due to its insulin inhibitory carbazoles. The various plants may help in the management of either type 2 diabetes due to insulin resistance or its insufficiency. Six plants with higher activities than glibenclamide gave the hope of discovering new templates for drug development. Ashes containing “antidiabetic” trace elements had better activities than their extracts, which were attributable to their insulinotropic effects. The most active antiplasmodial compound of G. latifolium was lupenyl acetate. Larvicidal plants may complement anti-malarial activities in malarial control. Absence of toxic elements may confirm the safety of these herbal drugs. Their additional hepatoprotective, anti-microbial, -trichomonal, -inflammatory and trypanocidal properties may account for reduced death of African sufferers using herbal drugs singly or co-administered with orthodox drugs. Implications of these results in the management of diabetes will be presented.

Evaluation of Ethnomedical Claim III: Anti‐hyperglycemic activities of Gongronema latifolium root and stem (民族药物需求评估III：Gongronema latifolium根与茎的降糖活性)

AbstractBackgroundThe insulinotropic activity of the combined root and stem of Gongronema latifolium (Asclepiadaceae) was evaluated to justify its African ethnomedicinal use in the management of diabetes.MethodsA methanolic extract and its chromatographic fractions (A1–A6) were tested for glucose‐reducing and in vitro insulin‐stimulating abilities using glucose‐loaded rats and INS‐1 cells, respectively. In vivo insulin‐releasing activities for the significantly (P &lt; 0.05) active antihyperglycemic A5 and A6 and in vitro insulinotropic activity of the C1 fraction and its isolated constituents were also similarly determined.ResultsThe extract (100 mg/kg) had higher in vivo antihyperglycemic activity than the individual A1–A6, indicating a synergistic effect of the plant constituents. Higher in vivo insulin release in response to A5 (100 mg/kg) than A6, agreed with their in vivo antihyperglycemic activities and confirmed insulin release as a mechanism of action of the plant. Compared with 5.6 mmol/L glucose (negative control), the extract and the A3, A6, and C1 (all at 100.0 μg/mL) elicited significantly higher in vitro insulin release that was similar to that of glibenclamide (1.0 μg/mL; P &gt; 0.05). Fraction C1 yielded a 1:1 mixture of α‐amyrin and β‐amyrin cinnamates (1a:1b), lupenyl cinnamate (2), lupenyl acetate (3), and two unidentified triterpenoids, Y and Z. The 1a:1b mixture (100.0 μg/mL) demonstrated the highest insulinotropic activity that was comparable (P &gt; 0.05) to that of glibenclamide (1.0 μg/mL).ConclusionsThe results confirm pancreatic activity as a mechanism underlying the antidiabetic action of G. latifolium and justify its ethnomedical use.

Evaluation of Ethnomedical Claims II: Antimalarial Activities of Gongronema latifolium Root and Stem

Methanolic extract and chromatographic fractions of Gongronema latifolium were tested against clinical isolates of Plasmodium falciparum-, P. yoelii nigeriensis-infected mice, chloroquine-sensitive (D6) and chloroquine-resistant (W2) P. falciparum clones. The isolates, characterized as a 1:1 mixture of α-amyrin and β-amyrin cinnamates (1a/1b), lupenyl cinnamate (2) and lupenyl acetate (3), were assayed using the clones. Extract, most active vacuum liquid and column chromatographic fractions had respective ED50 values of 120.85, 32.03, 25.62 mg.kg-1 and IC50 of 36.27, 9.45, 7.05 μg.mL-1, against W2 clones. Lupenyl acetate had 18.96 μg.mL-1, indicating synergistic action of the constituents. Results justified its ethnomedical use for treating malaria.

P 28: Some contributions to the evaluation of ethnomedical antidiabetic claims of African medicinal plants

Plants with ethnomedicinal claims in Africa have continued to play a key role in the management of diabetes. Some of these plants were evaluated to justify these claims, using normal, glucose- and alloxan-induced hyperglycaemic rats, and in vitro insulin secreting cell line (INS-1) models. Glibenclamide was the standard drug. Activity of Clausena lansium stem bark was attributed to the insulinotropic chalepin and imperatorin while that of Stachytarpheta cayennensis leaf was suggested to be mainly due to isoverbascoside. This was confirmed by the relative proportions of these constituents in the active fractions, as indicated by HPLC. The insulinotropic activities of Jatropha tanjorensis and Eugenia uniflora leaves were limited to their ethylacetate and n-hexane fractions, respectively. Quercetin and its glycoside (rutin), with in vitro insulinotropic and insulin inhibitory activities, respectively, were the respective major and minor constituents of the anti-hyperglycaemic Bauhinia monandra leaf fraction. In vivo, the two compounds were insulin stimulating, as rutin has been reported to be metabolised in the gut to quercetin. A 1:1 mixture of α-amyrin and β-amyrin cinnamates (1a/1b) was identified as the main insulinotropic constituent of Gongronema latifolium stem and root while contributions of lupenyl cinnamate (2), lupenyl acetate (3) and an unidentified triterpenoid Z confirmed the synergistic nature of the constituents. Also, insulin stimulation was reported as a hitherto unreported mechanism of action of this plant. The identification of these plants’ insulinotropic active constituents, comparable (p > 0.05) to glibenclamide, conclusively justified their antidiabetic claims. Additional six medicinal plants with better antihyperglycaemic activities than glibenclamide gave the hope of discovery of new templates for drug development. Antidiabetic activity of Murraya koenigii leaf was slow acting and suggested best for type 2 diabetes of insulin resistant aetiology, due to the insulin inhibitory activity of its extract and constituents. Murrayaquinone-A was the most active constituent with significant contributions from girinimbine and koenimbine. This shows that plants may help better in the management of type 2 diabetes due to insulin resistant or its insufficiency. The co-occurrence of antihyperglycaemic and hyperglycaemic, insulinotropic and insulin inhibiting fractions and constituents in these plants may confirm the safety margins of herbal drugs and the need to identify the active constituents. Additional hepatoprotective, anti-microbial, -parasitic, -infective, -hypertensive, -inflammatory and -malarial, etc properties of these herbs may account for the reduced death of the African diabetic patients using herbal drugs singly or co-administered with orthodox drugs. Stem and root juices of Musa paradisiaca “prevented/delayed” onset of diabetes in glucose loaded rats. Implications of these results in the management of diabetes and drug development will be presented.

P 29: Insulinotropic constituents and evaluation of ethnomedical claim of gongronema latifolium root and stem

Background and aims The insulinotropic activity of the combined root and stem of Gongronema latifolium was evaluated to justify its African ethnomedicinal use in the management of diabetes. Materials and Methods A methanolic extract of the combined root and stem and its vacuum liquid chromatographic fractions (A1–A6) were tested for glucose reducing and in vitro insulin stimulating abilities, using glucose loaded rats and INS-1 cells, respectively. In vivo insulin releasing activities for the significantly in vivo anti-hyperglycaemic active A5 and A6 were similarly determined, using glucose loaded rats. In vitro insulin stimulating potentials of column chromatographic fraction C1 and its isolated constituents were also determined. Results The extract (100 mg/kg) had higher in vivo anti-hyperglycaemic activity than A1-A6, indicating a synergistic effect of the plant constituents. Higher in vivo insulin release given by A5 (100 mg/kg) than that of A6, agreed with their in vivo anti-hyperglycaemic activities and confirmed insulin as a hitherto unreported mechanism of action of the plant. Extract, A3, A6 and C1 (100.0 μg/ml) elicited significantly high in vitro insulin release similar (p > 0.05) to glibenclamide (1.0 μg/ml). Fraction C1 gave a 1:1 mixture of α-amyrin and β-amyrin cinnamates (1a/1b), lupenyl cinnamate (2), lupenyl acetate (3) as well as two unidentified triterpenoids, Y and Z. The 1a/1b was an addition to the chemistry of the plant. The highest insulinotropic activity of 178.3% given by 1a/1b (100.0 μg/ml) was similar (p > 0.05) to that of glibenclamide (1.0 μg/ml). The 1a/1b, with contributions from 2, 3 and Z were the insulinotropic constituents. Some fractions and isolates demonstrated synergistic activity. Conclusion The results confirmed pancreatic activity as a mechanism of antidiabetic action of G. latifolium and justified this ethnomedical use.

Identification of Triterpenes from Milkweed (Asclepias syriaca)

The chloroform extract of Asclepias syriaca stem were investigated. Three triterpenes were isolated by TLC, VLC, and preparative chromatography, and their structures established by one and two-dimensional NMR spectroscopy. Lupenyl acetate has been isolated for the first time from A. syriaca; this is thefirst representative of a triterpene bearing a lupane skeleton in this species. In addition, alpha-amyrin acetate and alpha-amyrin butyrate were isolated.

Triterpenes and flavonoids from the roots of Mauritia flexuosa

Mauritia flexuosa L. f., Arecaceae, is an endemic species of South America. This species was studied with the intent to isolate the constituents of its roots. After the fractionation of the n-hexane and methanolic extracts from the roots of M. flexuosa, six triterpenes were obtained: friedelin, taraxerone, lupenyl acetate, lupenone, betulin and betulinic acid, along with three flavonoids: rutin, quercitrin and quercetin. All the compounds were identified by analysis of NMR and MS data and comparison with the literature. All those compounds are been reported for the first time in Mauritia, and the chemosystematic significance of the flavonoids isolated in this genus is discussed.

Triterpenoids from Vernonia auriculifera Hiern exhibit antimicrobial activity

Phytochemical investigation of Vernonia auriculifera afforded farnesylamine, a sesquiterpene amine that has not been found previously in plant species, together with lupenyl acetate, oleanolic acid, β-amyrin acetate, β-amyrin, friedelanone, friedelin acetate, α-amyrin and β-sitosterol. The compounds were characterized using nuclear magnetic resonace (NMR) spectroscopy and comparison with literature values. The isolated triterpenoids exhibited moderate antibacterial activity; α and β-amyrin had minimum inhibitory concentration (MIC) of 0.25 mg/ml against Staphylococcus aureus,Bacillus subtilis, Enterococcus faecium and Staphylococcus saprophyticus while lupenyl acetate and oleanolic acid exhibited MIC of 0.25 mg/ml againstStenotrophomonas maltophilia. Sub-MIC exposure of β-amyrin acetate was effective in decreasing adhesion of S. aureus, Klebsiella pneumonia and E. faecium while oleanolic acid decreased adhesion of K. pneumonia and Pseudomonas aeruginosasignificantly at sub-MIC. These compounds show potential for synergistic coupling with antimicrobial agents to improve therapeutic efficiency, in the face of rising bacterial resistance. Key words: Vernonia auriculifera, triterpenoids, farnesylamine, antibacterial activity.