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Prenylated flavonoids are a special kind of flavonoid derivative possessing one or more prenyl groups in the parent nucleus of the flavonoid. The presence of the prenyl side chain enriched the structural diversity of flavonoids and increased their bioactivity and bioavailability. Prenylated flavonoids show a wide range of biological activities, such as anti-cancer, anti-inflammatory, neuroprotective, anti-diabetic, anti-obesity, cardioprotective effects, and anti-osteoclastogenic activities. In recent years, many compounds with significant activity have been discovered with the continuous excavation of the medicinal value of prenylated flavonoids, and have attracted the extensive attention of pharmacologists. This review summarizes recent progress on research into natural active prenylated flavonoids to promote new discoveries of their medicinal value. [ABSTRACT FROM AUTHOR]

The phytochemical investigation of the methanol extract of the stem bark of Chrysophyllum lacourtianum led to the isolation and characterization of one new secondary metabolite, lacourtianal (1), together with eight known compounds. Compounds 2; 3; 5; 6; 7 and 9 were reported for the first time from Chrysophyllum genus. The structures of compounds 1–9 were elucidated on the basis of 1 D and 2 D NMR spectroscopic and mass spectrometric data as well as comparison with the literature. The antibacterial activity of the methanol extract, fractions and compounds 1–9 were evaluated against bacterial strains. The methanol extract exhibited moderate activity against Staphylococcus aureus NR4674 with MIC values of 500 µg/mL. The n-hexane fraction showed moderate activity against Staphylococcus aureus (ATCC 43300 and ATCC 25923) with MIC values of 125 µg/mL and ursolic acid (5) exhibited strong activity against Enterobacter aerogenes CPC and Escherichia coli ATCC 25322 with MIC values of 7.8 and 3.9 µg/mL respectively. [ABSTRACT FROM AUTHOR]

Oxidative stress (OS) is well established as a major event in Alzheimer's disease (AD) pathology. One of the mostly-researched classes of antioxidants to manage with overwhelming OS include flavonoids. This study was aimed to investigate the protective effect of A. congolensis extract (HEEAC) on AlCl3-mediated AD-like OS and assess the contribution of its antioxidant flavonoid contents. Female Wistar (250–300 g) rats received orally 50 mg/Kg bw of AlCl3, followed one hour later by doses (150 or 300 mg/kg) of HEEAC or vitamin E at 100 mg/kg daily for eight consecutive weeks. OS related biomarkers were evaluated at the end of treatment. To assess the contribution of flavonoid contents to its activity, HEEAC was fractioned using solvent of varying polarities. Flavonoid-rich extracts obtained were tested for their antioxidant capacity. AlCl3 administration significantly lowered antioxidant enzymes (catalase, glutathione peroxidase) and aconitase levels, reduced total thiol and thiol protein levels and increased lipid peroxidation and protein oxidation levels in brain. When co-administrated with HEEAC at 150 mg/kg, all of these OS related biomarkers were significantly moderated. The efficacity of the extract was significantly higher than vitamin E. Flavonoid-rich fractions extracted mainly n-butanol fraction show strong antioxidant activity, which can be considered as the major antioxidant fraction of this plant. HEEAC protect brain cells against oxidative damage induced by AlCl3, specifically through the strong antioxidant property of its n-butanol flavonoid-rich fraction, which may be a promising agent for preventing oxidative damage in AD. [ABSTRACT FROM AUTHOR]

Liver is an important part in human beings and plays a very important and major role in metabolism and excretion of xenobiotics from the body. Further, hepatotoxicity is caused by different types of toxic chemicals, such as antibiotics and chemotherapeutic agents, paracetamol (C8H9NO2), thioacetamide (C2H5NS), carbon tetrachloride (CCl4), silymarin (C25H22O10), ethanol (C2H5OH) and excessive alcohol intake and microbes is well researched. The markedly available synthetic drugs to treat liver sickness in this condition also cause further damage to the liver. Therefore, herbal medicines have become increasingly famous and their utilization is wide-spread. In medicinal plant derived drugs, that have been utilized in the treatment of liver diseases for a long time, the protection of a healthy liver has been essential for the overall well-being of an individual. Liver injury induced by toxins is more common now-a-days. Herbal remedies are focused in the pharmaceutical industry to evolve a safe route for liver disorders and it is very low cost, no side effects compared with synthetic drugs. Therefore, hepatoprotective plants such as Avicennia alba, Anisochilus carnosus, Baliospermum montanum, Centella asiatica, Clitoria ternatea, Eclipta alba, Justicia adhatada, Phyllanthus emblica, Pisonia grandis and Syzgium cumini were reviewed. The present review is aimed at compiling data on promising phytochemicals from medicinal plants that have been tested in hepatotoxicity models using modern scientific system. [ABSTRACT FROM AUTHOR]

Background: A perusal of the literature suggested that Manilkara zapota (L.) P. Royen stem bark (MZSB) is enriched with several bioactive phytoconstituents but had not been yet screened for its in vitro and in vivo antidiabetic potentials. Thus, the present study aimed to investigate the effects of 70% ethanolic extract of Manilkara zapota (L) P. Royen stem bark (EMZSB) in DPPH- and H2O2-scavenging assay, in vitro α-glucosidase inhibition assay, ameliorating diabetes and its complications in alloxan-induced diabetes in Wistar rats. Results: With a maximum extractive yield of 9.16% w/w, EMZSB has shown the presence of various phytochemicals like flavonoids, phenolic compounds, tannins, anthraquinone glycosides, steroids, terpenoids, and alkaloids. EMZSB has elucidated a considerable in vitro free radical scavenging potential by DPPH and H2O2 assays when compared with absolute ethanolic extract of Manilkara zapota (L) P. Royen stem bark (AEMZSB), while ascorbic acid was taken as the standard. Further, EMZSB demonstrated high in vitro α-glucosidase enzyme inhibition potential (IC50 = 119.79 ± 1.52 µg/mL) than AEMZSB (IC50 = 129.92 ± 2.29 µg/mL) with a significant difference (p < 0.01), when acarbose was taken as reference inhibitor (IC50 = 86.43 ± 1.26 µg/mL). During acute toxicity studies EMZSB was safe up to 2000 mg kg−1 doses while, found causing moribund status followed by mortality in mice at 3000 mg kg−1 and above doses. A preliminary antidiabetic study with EMZSB-250 mg kg−1 in normal rats showed no sign of hypoglycemia; however, a dose-dependent antihyperglycemic effects were observed in oral glucose tolerance test in glucose-loaded rats. In vivo assessment with EMZSB-250 mg kg−1 in alloxan-induced rats demonstrated significant blood glucose-lowering effects with perfection in serum lipid profile, body weight enhancement, cardiovascular risk indices, nephroprotective effects, augmentation in liver glycogen content, and histopathological evidence of normal architecture of kidneys with no marks for nephritis. Conclusions: EMZSB-250 showed significant antidiabetic effects and ameliorated diabetic complications by improving glycemic control and accompanying biochemical alteration. [ABSTRACT FROM AUTHOR]

Background: Stingless bees or meliponines (family Apidae, subfamily Meliponinae, tribe Meliponini) are eusocial bees from tropical and subtropical regions. Propolis of Scaptotrigona aff. postica (Latreille, 1807) is used in the state of Maranhão (Northeast Brazil) in ointments to treat tumors and wounds. Samples of propolis of S. aff. postica (Apidae, Meliponini) were collected monthly from an apiary located in Barra do Corda (state of Maranhão, Northeast Brazil). Extracts of the 12 samples were obtained with 80% ethanol. Constituents of the samples were characterized by high performance liquid chromatography coupled to photodiode array detector and electrospray ionization tandem mass spectrometry analysis, amounting to 100 substances. Results: Representatives of several classes of secondary metabolites were characterized, including benzoic and cinnamic acids, flavonoids (chalcones, flavone‐C‐glycosides, flavonol aglycones, and glycosides), alkyl and alkenyl resorcinols, xanthones, diterpenes, cycloartane‐type triterpenoids, pentacyclic triterpenoids, pyrrolizidine alkaloids, and hydroxycinnamic acid amides (HCAAs). Considerable qualitative differences in chemical composition among samples were observed, depending on the year period of collection. Principal Coordinate Analysis recognized three distinct year periods (Jan–Mar, April–Sep, Oct–Dec) according to the corresponding chemical profiles. Conclusion: Compared with previous studies, the present work indicates that considerable differences in chemical composition occur also from year to year. Contrary to most propolis types reported so far, which derive exclusively or mostly from a single botanical source, the propolis from Barra do Corda seemingly depends on several resin sources. It is suggested that chalcones and flavonols stem from Mimosa tenuiflora (Mimosoideae); resorcinols, xanthones, and cycloartane‐type triterpenoids, from fruits of Mangifera indica (Anacardiaceae); pyrrolizidine alkaloids, possibly from some Crotalaria species (Faboideae); HCAAs probably originate from pollen contaminating the propolis samples. The propolis of S. aff. postica poses challenges and possibilities of study for apicultural researchers, chemists, and pharmacologists. [ABSTRACT FROM AUTHOR]

Pseudocedrela kotschyi (Schweinf) Harms (Meliaceae) is an important medicinal plant found in tropical and subtropical countries of Africa. Traditionally, P. kotschyi is used in the treatment of various diseases including diabetes, malaria, abdominal pain and diarrhoea. To provide an overview of traditional medicinal claims, pharmacological properties, and phytochemical principles of P. kotschyi as a basis for its clinical applications and further research and development of new drugs. Through interpreting already published scientific manuscripts retrieved from different scientific search engines, namely, Medline, PubMed, EMBASE, Science Direct and Google scholar databases, an up-to-date review on the medicinal potentials of P. kotschyi from inception until September, 2020 was compiled. 'Pseudocedrela kotschyi', 'traditional uses', 'pharmacological properties' and 'chemical constituents' were used as search words. At present, more than 30 chemical constituents have been isolated and identified from the root and stem bark of P. kotschyi, among which limonoids and triterpenes are the main active constituents. Based on prior research, P. kotschyi has been reported to possess anti-inflammatory, analgesic, antipyretic, anthelminthic, antimalaria, anti-leishmaniasis, anti-trypanosomiasis, hepatoprotective, antioxidant, antidiabetic, antidiarrheal, antimicrobial, and anticancer effects. P. kotschyi is reported to be effective in treating a variety of diseases. Current phytochemical and pharmacological studies mainly focus on antimalaria, anti-leishmaniasis, anti-trypanosomiasis and anticancer potential of the root and stem bark of P. kotschyi. Although experimental data support the beneficial medicinal properties of this plant, there is still a paucity of information on its toxicity profile. Nonetheless, this review provides the basis for future research work. [ABSTRACT FROM AUTHOR]

The present study provides an overview, focusing on the botanical aspects, phytochemistry, ethnopharmacology and biological activities reported for species from the tribe Vismieae (Hypericaceae). These species, traditionally distributed in three genera (Vismia, Psorospermum and Harungana), occur predominantly in tropical areas of South America, mainland Africa and Madagascar, where several of them are used in the traditional medicine mainly as febrifugal, antimalarial and for treating wounds of diverse origin. The phytochemical investigations indicated that the plants produce anthraquinones, anthrones, xanthones, benzophenones, flavonoids and some terpenoids. A number of 221 different compounds were obtained from 32 species of the tribe. Several compounds were investigated for the pharmacological activities, being cytotoxic and antimicrobial the most cited. Nevertheless, a number of pharmacological researches were carried out with extracts and some findings experimentally evidenced the ethnopharmacological usefulness of several species. The distribution of the anthracenic derivatives, xanthones and benzophenone precursors is not uniform in the genera. Thus, the substitution pattern of these compounds was analyzed and the systematic relationship among the taxa is discussed in the light of these features. Of note, more species need chemical investigation in order to make a judgment about the taxonomic significance of the compounds, but it seems that, although the tribe has a certain homogeneity, each genus has particularities. Considering this statement, it is possible to say that in the chemical point of view, Psorospermum is diferent from Harungana and both are diferent from Vismia, which is clearly separate into two distinct groups, the African and the American species. [ABSTRACT FROM AUTHOR]

The objective of this work was to establish a scientific basis for the antibacterial action of chemical constituents isolated from Cordia myxa (Boraginaceae). The isolation and characterization of compounds were carried out respectively by using column chromatography, 1H NMR and 13C NMR, HSQC, HMBC, COSY, and by comparing with literature data. Compound 2 was tested on two gram (-) bacteria, E. coli and Salmonella typhi. in Mueller-Hinton agar and broth. Several classes of antibiotics were tested on the two strains; those with the best results were considered as references and methanol as the negative control. Two new terpenoids were isolated from the roots and branches of Cordia myxa. Compound 1, the 3β-urs-12, 20(30)-dien-28-oic-acid was isolated from the branches and compound 2, the Cordiridoid A which is a bisiridoid, was isolated from the roots. It is for the first time that, these compounds were described from the Cordia myxa and it is the first time that bisiridoids are reported from the Cordia genus. The results revealed the antibacterial activity on the bacterial strains at a dosedependent. However, the larger dose of 40mg/ml had better antibacterial potential on both E. coli (diameter of inhibition zone, DIZ=19±0.1 mm; Minimum inhibition concentration, MIC=40mg/ml; MIC=0.5mg/ml) and Salmonella typhi (DIZ=22±0.1mm; 40mg/ml; MIC=0.28mg/ml) strains. [ABSTRACT FROM AUTHOR]

Background: Antibiotic resistance has contributed to the burden of infectious diseases both in the hospital and community setting, and represents a great threat to public health. Previous studies have revealed the role of reactive oxygen species as intermediate mediators of tissue damage, following antibiotherapies, indicating the need of associating antioxidants to these treatments. Therefore, the present work was designed to study the antibacterial, antifungal and antioxidant activities of extracts and compounds from Rumex abyssinicus Jacq. (Polygonaceae), as well as to investigate the antibacterial mechanisms of action of the most effective agents. Methods: The plant extracts were prepared by maceration in organic solvents followed by column chromatography of the EtOAc fraction and purification of different fractions which led to the isolation and characterization of pure compounds. The antimicrobial activities of the extracts/compounds and their combinations with ciprofloxacin and fluconazole were evaluated using the broth microdilution method by determining the minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC). The effects of the extracts on the bacterial cell membrane and microbial respiratory chain dehydrogenase enzyme activity were determined by spectrophotometric methods. Antioxidant activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and gallic acid equivalent antioxidant capacity (GAEAC) assays. Results: Chrysophanol (1), physcion (2), Ergosta-6,22-diene-3,5,8-triol (3), emodin (4), 6-hydroxyemodin (citreorosein) (5), chrysophanein (6) and physcionin (7) were isolated from EtOAc fraction of R. abyssinicus and displayed different degrees of antimicrobial activities (MIC = 8–256 μg/mL). The MeOH extract and compounds 2 and 4 exhibited synergistic effects with ciprofloxacin and fluconazole. Compounds 1, 2 and the combined mixture of 6 + 7 displayed the highest antioxidant activity (GAEAC = 83.38–106.03 μg/mL). Conclusion: R. abyssinicus is a potential source of antibacterial, antifungal and antioxidant agents. The antibacterial mechanisms of action of the MeOH extract and compound 2 are due to disruption of the cytoplasmic membrane and inhibition of the microbial respiratory chain dehydrogenase enzyme activity. To the best of our knowledge, this is the first report of test samples and ciprofloxacin / fluconazole association against MDR strains. The observed activity of the isolated compounds against bacteria and fungi including MDR strains deserves further exploration. [ABSTRACT FROM AUTHOR]

Copyright of Boletín Latinoamericano y del Caribe de Plantas Medicinales y Aromáticas is the property of Universidad de Santiago de Chile and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Melanoma is the most aggressive type of skin cancer and originates from pigment-containing cells called melanocytes. The incidence of melanoma has been increasing worldwide. In the current study, the cytotoxic and photo-cytotoxic activities of different medicinal plants from Lamiaceae (Salvia cedronella, Salvia chionantha, and Salvia adenophylla), Asteraceae (Klasea kurdica, Klasea bornmuelleri, and Achillea millefolium), Apiaceae (Cuminum cyminum, and Anethum graveolens), and Polygonaceae (Rumex crispus) families were studied against HT 144 (Human malignant melanoma) cancer cell lines. The activities were performed by employing the MTT assay. Moreover, the apoptotic effects of the plant extracts were investigated by flow cytometry with annexin V/PI dual staining technique. The production of intracellular ROS by DCFH-DA technique and the effects of TNF-α secretion on apoptosis were also investigated. All plant extracts exhibited cytotoxic, and photo-cytotoxic effects against HT 144 cancer cells. Salvia species and Klasea species induced apoptosis via intracellular ROS generation secreted by TNF-α. On the other hand, A. millefolium, C. cyminum, A. graveolens, and R. crispus extracts induced apoptosis due to the intracellular generation of ROS, but, via the different pathway. In conclusion, this study indicates that the tested medicinal plant extracts have the potential in the treatment of melanoma. [ABSTRACT FROM AUTHOR]

The dried stem bark (500 g) of I B. maingayi i was ground and extracted exhaustively for 12 h by Soxhlet extraction with hexane followed by dichloromethane (DCM). The hexane extract was separated on a silica gel column using a gradient hexane-DCM to give vanillin ( B 6 b ) (15 mg), vanillic acid ( B 7 b ) (16 mg), -sitosterol ( B 8 b ) (20 mg), -sitostenone ( B 9 b ) (18 mg), and taraxerol ( B 10 b ) (25 mg). The crude alkaloid was submitted to exhaustive column chromatography over silica gel using DCM gradually enriched with methanol to yield 18 fractions. [Extracted from the article]

In this study, the mechanism underlying acetylcholinesterase (AChE) and 5-lipoxygenase (LOX) inhibition by two novel alkaloids, beilschglabrine A and beilschglabrine B, as well as their interaction footprints on the binding pockets were investigated. The results showed that beilschglabrine A and beilschglabrine B inhibit both AChE and LOX in a competitive manner by binding to their active sites thereby interfering with substrate access. The interaction of the alkaloids with the enzymes was favorable and stable with low binding energy values which correlate well with their IC 5 0 . The depicted molecular interaction, structure-energetic pattern and binding conformations confirmed that beilschglabrine A is more potent than beilschglabrine B. The differences in the binding pose and potency of the alkaloids is occasioned by an extra methyl moiety on beilschglabrine B. The chemical scaffold of the alkaloids respected Lipinski's rule of five and may be relevant in the development of new anti-inflammatory and anti-neurodegenerative disease drugs acting via AChE and LOX inhibition. The mechanism underlying acetylcholinesterase (AChE) and 5-lipoxygenase (LOX) inhibition by two novel alkaloids, beilschglabrine A and beilschglabrine B, as well as their interaction footprints on the binding pockets were investigated. The interaction of the alkaloids with the enzymes was favorable and stable with low binding energy values which correlate well with their IC50. The depicted molecular interaction, structure-energetic pattern and binding conformations confirmed that beilschglabrine A is more potent than beilschglabrine B. [ABSTRACT FROM AUTHOR]

Abstract: A novel isoflavone-chromone flavonoid C-O-C dimmer, brevipedicelone D (1), along with one new C-O-C biflavonoid derivative, brevipedicelone E (2), were isolated from the ethyl acetate extract of the leaves of Garcinia brevipedicellata, a medicinal plant used in folk medicine in parts of Cameroon. Their structures were elucidated by extensive spectroscopic techniques, including 1D- and 2D- NMR, MS experiments, as well as comparing their spectral data with those of known analogues. Anti-onchocercal screening of 1 showed moderate inhibition of adult worm motility of Onchocerca ochengi by 60% at the highest concentration (20 µg/mL) and inhibited motility of both the juvenile worms of O. ochengi and Loa loa by 90% at this same concentration.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Background: Although Galanthus nivalis L. (snowdrop) is known for the galanthamine content, used in the treatment of Alzheimer disease, the polyphenolic compounds of Amaryllidaceae species are less studied. Proper understanding of the polyphenolics in these extracts and of their antioxidant and antimicrobial properties may allow a reconsideration of their medicinal uses. Methods: The polyphenolic content of four selected Amaryllidaceae species harvested from Romania ( Galanthus nivalis L., Narcissus pseudonarcissus L., N. poeticus L. and Leucojum vernum L.) was determined by spectrophotometric methods; the identification of phenolic compounds was performed by a HPLC-MS method, in order to establish their polyphenolic fingerprints. For the evaluation of the antioxidant potential the following methods were employed: DPPH radical scavenging, FRAP, hemoglobin ascorbate peroxidase activity inhibition (HAPX), inhibition of lipid peroxidation catalyzed by cytochrome c , and electron paramagnetic resonance (EPR) spectroscopy assays. Antimicrobial activity was assessed using the disc diffusion method. Results: Qualitative and quantitative analyses highlight important amount of polyphenols (over 15 mg/g); the main identified compounds are chlorogenic and p -coumaric acids in all species. Only G. nivalis shows antioxidant activity by all the used methods. G. nivalis and L. vernum strongly inhibits the growth of S. aureus , while N. poeticus shows a very good antifungal activity. Conclusions: The results of this study provide a new approach to the properties and therapeutic uses of some Romanian widespread Amaryllidaceae species that could be considered sources of developing new medicinal products with anti anti-staphylococcal and antifungal activity. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial resistance is a serious threat against humankind and the search for new therapeutics is needed. This study aims to investigate the antimicrobial and antioxidant activities of ethanol extracts and compounds isolated from Dissotis senegambiensis and Amphiblemma monticola, two Cameroonian Melastomataceae species traditionally used for the treatment of fever, malaria and infectious diseases. Methods: The plant extracts were prepared by maceration in ethanol. Standard chromatographic and spectroscopic methods were used to isolate and identify fourteen compounds from the two plant species [1–6 (from D. senegambiensis), 3, 4 and 7–14 (from A. monticola)]. A two-fold serial micro-dilution method was used to determine the minimum inhibitory concentration (MIC) against four bacterial strains including two resistant bacterial strains, methicillin resistant S. aureus (MRSA3) and methicillin resistant S. aureus (MRSA4) and three yeast strains. Results: The fractionation of EtOH extracts afforded fourteen compounds belonging to triterpenoid and phenolic derivatives. The ethanol extracts, compounds 3, 5–8, 10 and the mixture of 10 + 12 were active against all the tested bacterial and fungal species. Compound 7 (MIC = 16–32 μg/mL) and 10 (MIC = 8–16 μg/mL) displayed the largest antibacterial and antifungal activities, respectively. Compounds 7, 10 and the mixture of 10 + 12 showed prominent antibacterial activity against methicillin- resistant S. aureus (MRSA) which is in some cases equal to that of ciprofloxacin used as reference antibacterial drug. Compound 8 also showed high radical-scavenging activities and ferric reducing power when compared with vitamin C and butylated hydroxytoluene used as reference antioxidants. The tested samples were non-toxic to normal cells highlighting their good selectivity. Conclusions: The result of this investigation reveals the potential of D. senegambiensis and A. monticola as well as the most active compounds in the search for new antimicrobial and antioxidant agents. So, further investigations are needed. [ABSTRACT FROM AUTHOR]

In the presence of a CuBr·SMe2 catalytic system, a very simple and efficient approach for the synthesis of the key precursor of the core of endiandric acids starting from the readily and abundantly available 3-butyn-1-ol in five linear steps with an overall yield of 40% was developed. [ABSTRACT FROM AUTHOR]

Background: Cancer still constitutes one of the major health concerns globally, causing serious threats on patients, their families, and the healthcare system. Methods: In this study, the cytotoxicity of the methanol extract of Elephantopus mollis whole plant (EMW), Enantia chlorantha bark (ECB), Kalanchoe crenata leaves (KCL), Lophira alata bark (LAB), Millettia macrophylla leaves (MML) and Phragmanthera capitata leaves (PCL) towards five human solid cancer cell lines and normal CRL2120 fibroblasts, was evaluated. Extracts were subjected to qualitative chemical screening of their secondary metabolite contents using standard methods. The cytotoxicity of samples was evaluated using neutral red uptake (NR) assay meanwhile caspase activation was detected by caspase-Glo assay. Flow cytometry was used to analyze the cell cycle distribution and the mitochondrial membrane potential (MMP) whilst spectrophotometry was used to measure the levels of reactive oxygen species (ROS). Results: Phytochemical analysis revealed the presence of polyphenols, triterpenes and sterols in all extracts. The IC50 values of the best samples ranged from 3.29 µg/mL (towards DLD-1 colorectal adenocarcinoma cells) to 24. 38 µg/mL (against small lung cancer A549 cells) for EMW, from 2.33 µg/mL (mesothelioma SPC212 cells) to 28. 96 µg/mL (HepG2 hepatocarcinoma) for KCL, and from 0.04 µg/mL (towards SPC212 cells) to 0.55 µg/mL (towards A549 cells) for doxorubicin. EMW induced apoptosis in MCF-7 cells mediated by MMP loss and increased ROS production whilst KCL induced apoptosis via ROS production. Conclusion: This study provides evidences of the cytotoxicity of the tested plant extract and highlights the good activity of Elephantopus mollis and Kalanchoe crenata. They deserve more exploration to develop novel cytotoxic drugs. [ABSTRACT FROM AUTHOR]

Free radicals are highly reactive molecules generated during oxidation reactions which in turn initiate chain reactions resulting to cellular damage. There is substantial evidence implicating free radicals especially reactive oxygen species (ROS) in the etiology of more than one hundred degenerative disorders in humans including, arthritis, atherosclerosis, ischemia and reperfusion injury of many tissues, gastritis, diabetics, central nervous system injury, acquired immunodeficiency syndrome (AIDS) and cancer. Scientific evidence postulates that bioactive compounds especially from natural products are capable of providing protection against free radicals. Consequently, few decades have witnessed a surfeit of research geared towards validating the antioxidant and hepatoprotective potential of the natural products. In this review, African natural products whose antioxidants activities were scientifically validated either in their crude extracts and/or derived products have been discussed. A total 1076 plants species representing 287 family, 132 isolated compounds and 7 insect/mollusk secreation were found. The plant species from the following families; Fababceae, Asteraceae, Lamiaceae, Moraceae, Euphorbiaceae, Combretaceae and Malvaceae have received more scientific attention than others. Analysis of the reports revealed that Combretum apiculatum, Telfaria occidentalis, Acalypha racemosa, Garcinia lucida were the most active plant extracts from African flora. The most active ROS-detoxifying phytochemicals were moracin T, U, S and R ( 84- 87), oleanolic acid ( 54), 5,7,4′-trihydroxy-3,8,3′,5′-tetramethoxyflavone ( 89), 5,7,3′-trihydroxy-3,8,4′,5′-trimethoxyflavone ( 88), luteolin (3′,4′,5,7-tetrahydroxy flavone) ( 117) and genistein (4′,5,7-trihydroxyisoflavone) ( 116). The significant antioxidant potential demonstrated by some crude extracts and their constituent compounds render them good candidates for the development of new drugs. Although, the study of the mechanisms of actions as well as clinical validation of some of these isolated compounds is lacking. It is hoped that pertinent scientist and stakeholders will look further into some of these compounds for detailed authentification and subsequent commercialization. [ABSTRACT FROM AUTHOR]

Copyright of Marmara Pharmaceutical Journal is the property of Marmara University, Faculty of Pharmacy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Marmara Pharmaceutical Journal is the property of Marmara University, Faculty of Pharmacy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two new protocols for exploring antioxidant-related chemical composition and reactivity are described: one based on a chronometric variation of a haemoglobin ascorbate peroxidase assay and one based on cytochrome c-induced oxidation of lecithin liposomes. Detailed accounts are given on their design, application, critical correlations with established methods and mechanisms. These assays are proposed to be physiologically relevant and bring new information regarding a real sample, both qualitative and quantitative. The well-known assays used for evaluation of antioxidant (re)activity are revisited and compared with these new methods. Extracts of the Hedera helix L. are examined as test case, with focus on seasonal variation and on leaf, fruit and flower with respect to chromatographic, spectroscopic and reactivity properties. According to the set of assays performed, winter are the most antioxidant, followed by summer leaves, and then by flowers and fruits. [ABSTRACT FROM AUTHOR]

Context: The ethnopharmacological study ofBeilschmiediaindicates that several species are used for the treatment of various ailments. Objective: This is the first study of the chemical composition ofBeilschmiedia pulverulentaKosterm (Lauraceae) essential oil and its antioxidant, antimicrobial, antityrosinase, anti-inflammatory, and anticholinesterase activities. Materials and methods: The antioxidant activities were evaluated by β-carotene, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ferric-reducing antioxidant power (FRAP), and phenolic content at different concentrations. The antimicrobial activities against Gram-positive and Gram-negative bacteria and fungi were revealed by disk diffusion and microdilution. The antityrosinase and anti-inflammatory activities were assayed against mushroom tyrosinase and lipoxygenase enzymes. The anticholinesterase activity was analyzed using acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Results: Forty-two components were detected inB. pulverulentaoil with eugenol (45.3%) being the major component. The oil phenolic content and the FRAP were 660.1 mg gallic acid/g and 604.0 mg ascorbic acid/g, respectively. The oil gave an IC50value of 94.5 µg/mL and an inhibition of 93.9% in DPPH and β-carotene, respectively. The antimicrobial activity showed that the oil had strong activity against all Gram-positive bacteria with an minimum inhibitory concentration (MIC) value each of 62.5 µg/mL and moderate against all fungi with MIC and minimum bactericidal concentration (MBC) values each of 125 µg/mL. The oil showed significant antityrosinase and anti-inflammatory activities with 67.6 and 62.5% inhibition, respectively. In addition, the oil had moderate AChE (56.5%) and BChE (48.2%) activities. Discussion and conclusion: The results show that the oil could potentially be used for nutraceutical industries, food manufactures, and therapeutic agents against various diseases such as inflammation and rheumatism. [ABSTRACT FROM PUBLISHER]

In northern New Zealand,Beilschmiedia tawahas shown recruitment failure in some sites. TheBeilschmiediagenus has been shown to contain allelopathic compounds in its leaves and bark. In addition, the distribution of the main seed disperser for tawa, the kererū (Hemiphaga novaeseelandiae), has declined in recent years. In this study I assessed whetherB. tawaleaf leachate can affect recruitment ofB. tawa, particularly in disturbed sites. I also tested whether simulated endozoochory (removal of mesocarp) had an effect on germination. Results show that under laboratory conditions, leachate can have either a negative or a positive effect, depending on the concentration. At high concentrations (1:1), higher than normally experienced in the field, radicles were shorter than in the less concentrated treatment. At lower concentrations (1:50) there was a 50% higher germination index compared with the control and high concentration (1:1) treatments. Using soils from sites with different levels of anthropogenic disturbance did not have an effect on germination or hypocotyl length. Removal of the mesocarp positively affected germination (1.5-fold). Based on the results of this study, inhibition of germination and growth ofB. tawais unlikely to be caused by phytotoxicity of their own leachate under field conditions. [ABSTRACT FROM AUTHOR]

Background: The present study was designed to investigate the antibacterial activities of the methanol extracts from different parts of Beilschmedia acuta Kosterm (Lauraceae), Clausena anisata (Willd) Hook (Rutaceae), Newbouldia laevis Seem (Bignoniaceae) and Polyscias fulva (Hiern) Harms (Araliaceae) as well as their synergistic effects with antibiotics against a panel of Gram-negative bacteria, including multi-drug resistant (MDR) phenotypes expressing active efflux pumps. Methods: Broth microdilution method was used to determine the minimum inhibitory concentrations (MICs) and the minimum bactericidal concentrations (MBCs) of the extracts, as well as those of antibiotics in association with the most active ones, B. acuta, N. laevis and P. fulva. Results: MIC values obtained indicate that extracts from the bark of B. acuta were active on all the 26 tested Gram-negative bacteria, with MICs ranging from values below 8 to 256 µg/mL. Other samples displayed selective activities, their inhibitory effects being observed on 9 (34.62 %) of the 26 bacterial strains for N. laevis leaves extract, 6 (23.10 %) for both C. anisata leaves and roots extracts, 7 (26.9 %) and 4 (15.4 %) for leaves and roots extracts of P. fulva respectively. Extract from B. actua bark displayed the best antibacterial activity with MIC values below 100 µg/mL against 16 (61.5 %) of the 26 tested microorganisms. The lowest MIC values (below 8 µg/mL) were obtained with this extract against Escherichia coli W3110 and Klebsiella pneumoniae ATCC11296. The MIC values of this extract were lower than those of ciprofloxacin against E. coli W3110, Enterobacter aerogenes ATCC13048, CM64 and Providencia stuartii NAE16. At MIC/2, the best percentages of synergistic effects (100 %), were obtained with B. acuta bark extract and tetracycline (TET) as well as with P. fulva leaves extract and TET and kanamycin (KAN). Conclusion: The overall results of the present study provide information for the possible use of the studied plants and mostly Beilschmedia acuta in the control of bacterial infections including MDR phenotypes. [ABSTRACT FROM AUTHOR]

Background: Due to their genetic proximity, chimpanzees share with human several diseases including bacterial, fungal and viral infections, such as candidiasis, acquired immune deficiency syndrome (AIDS), Ebola virus disease. However, in its natural environment, chimpanzees are tolerant to several pathogens including simian immunodeficiency virus (SIV), virus related to human immunodeficiency virus (HIV) that contribute to the emergence of opportunistic diseases such as microbial infections. Methods: Twenty seven species of plants consumed by chimpanzees were evaluated for their antimicrobial potential against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, Candida tropicalis and Candida glabrata using the agar diffusion technique and micro-dilution in 96-well plates. In total 132 extracts (33 dichloromethane, 33 methanol, 33 ethyl acetate and 33 aqueous) were tested. Results: The results showed that 24 extracts (18 %) showed activity against bacteria and 6 extracts (5 %) were active against yeasts. The minimal inhibitory concentrations (MICs) values of active extracts ranged between 23 and 750 μg/ ml for bacteria and between 188 and 1500 μg/ml for yeasts. Conclusion: Tristemma coronatum was the most promising on the studied microorganisms followed by Beilschmiedia mannii. The extracts of the two plants indicated by chimpanzees have potential for antimicrobial use in human. [ABSTRACT FROM AUTHOR]

Background: Naturally occurring flavonoids have been reported to possess various pharmacological properties. The aim of this study was to evaluate the antimicrobial and antioxidant activities of the MeOH extract and flavonoids from the leaves of Oncoba spinosa, a plant used for the treatment of syphilis, wounds and sexual impotence. Methods: The plant extract was prepared by maceration in methanol and sequentially fractionated by column chromatography. The structures of isolated compounds were elucidated on the basis of spectral studies and comparison with published data. The MeOH extract and its isolated compounds were evaluated for their antibacterial and antifungal activities by broth microdilution method. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) and trolox equivalent antioxidant capacity (TEAC) assays were used to detect the antioxidant activity. The samples were tested spectrophotometrically for their hemolytic properties against human red blood cells. Results: The fractionation of the MeOH extract afforded five known flavonoids including kaempferol (1), quercetin (2), apigenin-7-O-β-D-glucuronopyranoside (3), quercetin 3-O-β-D-galactopyranoside (4) and quercetin 3-O-α-Lrhamnopyranosyl (1→6) β-D-glucopyranoside (5). The MeOH extract displayed weak to moderate antimicrobial activities (MIC = 256-2048 μg/ml). Quercetin 3-O-α-L-rhamnopyranosyl (1→6) β-D-glucopyranoside (5) and quercetin (2) were respectively the most active compounds against bacteria (MIC = 8-64 μg/ml) and fungi (MIC = 64 - 128 μg/ml). These tested samples also showed high radical-scavenging activities (EC50 = 5.08 - 70.56 μg/ml) and gallic acid equivalent antioxidant capacities (TEAC = 53.76 - 89.86 μg/ml) when compared with vitamin C (EC50 = 4.72 μg/ml). The MeOH extract and compounds 2-5 were non-toxic to human red blood cells indicating their high selectivity to be used as antimicrobial and antioxidant drugs. Conclusion: The MeOH extract of O. spinosa as well as compounds 2 - 5 could be a potential source of natural antimicrobial and antioxidant products. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of leaves and stem bark extracts of Clausena anisata monitored by liquid chromatography high-resolution mass spectrometry (LC-HR-MS) analysis led to the isolation and characterization of twenty-one secondary metabolites: four carbazole alkaloids ( 1- 4) including one new name clausamine H ( 1), fourteen coumarins ( 5- 18), two porphyrin derivatives ( 19- 20), and one limonoid ( 21). Crude extracts were analyzed first by LC-HR-MS, and target compounds were isolated by a multi-step separation procedure using column chromatography and preparative high-performance liquid chromatography ( prep-HPLC) monitored by LC-HR-MS analysis. The structures of isolates were determined by means of spectroscopic and spectrometric data, as well as by comparison with literature values. The isolates showed weak to high antibacterial activities with imperatorin ( 14) being the most active one. Cytotoxic activities against HeLa and monkey Vero cells were also investigated, and murrayamine-A ( 4), 3-(1,1-dimethyl allyl) xanthyletin ( 5) gravelliferone ( 7), excavatin D ( 10), 7-[(E)-7-hydroxy-3,7-dimethylocta-2,5-dienyloxyl]-coumarin ( 13), phellopterin ( 15), and 1- O-methylclausenolide ( 21) were found active with LC values ranged from 1.14 to 3.26 µg/mL and a good selectivity index values (SI 38.20-231.58) against the HeLa cells. However, these compounds were non-toxic to normal cells indicating their high potential to be used as anticancer drug. [ABSTRACT FROM AUTHOR]

Background The rapid spread of bacteria expressing multi-drug resistance propels the search for new antibacterial agents. The present study was designed to evaluate the antibacterial activities of the methanol extracts from Beilschmiedia obscura and six other Cameroonian plants against a panel of twenty nine Gram-negative bacteria including Multi-drug resistant (MDR) phenotypes. Methods The phytochemical investigations of the extracts were carried out according to the standard methods and the liquid micro-dilution assay was used for all antibacterial assays. Results Phytochemical analysis showed the presence of alkaloids in all studied extracts. Other chemical classes of secondary metabolites such as anthocyanines, anthraquinones flavonoids, saponins, tannins, sterols and triterpenes were selectively detected in the extracts. The extract from the fruits of Beilschmiedia obscura, Pachypodanthium staudtii leaves and Peperomia fernandopoiana (whole plant) displayed the best spectrum of activity with MIC values ranging from 16 to 1024 μg/mL against at least 65% and above of the tested bacteria. The extract from Beilschmiedia obscura was the most active with MIC values below 100 μg/mL against ten of the tested bacteria. This extract also showed MBC values below 1024 μg/mL against 55.17% of the studied microorganisms. Phenylalanine arginine β-naphthylamide (PAβN) significantly modulated the activities of extracts from the leaves and fruits of Pachypodanthium staudtii and Beilschmiedia obscura respectively, by increasing their inhibitory activity against Klebsiella pneumoniae KP55 strain at least four fold. Conclusion The overall results of the present investigation provide information for the possible use of the methanol extracts of the studied plant species, especially B. obscura to fight infectious diseases caused by Gram-negative bacteria including MDR phenotypes. [ABSTRACT FROM AUTHOR]

From the previous studies of chemical compositions of essential oils of I Beilschmiedia i species and from the above-mentioned results, it can be observed that the major components in the essential oils of I Beilschmiedia i species are varied. In a continuation of our systematic studies on volatile oils from Malaysian I Beilschmiedia i species, we describe in this paper an evaluation of the chemical composition of the essential oil from the leaf of I B. insignis i . Among them are I Ocotea usambarensis i (bark oil: 24.8%) [[9]], I Cryptocarya stocksii i (leaf oil: 23.09%) [[10]], I Lindera erythrocarpa i (leaf oil: 18.73%) [[11]], and I Machilus zuihoensis i (leaf oil: 10.5%) [[12]]. [Extracted from the article]

Gnidia glauca and Dioscorea bulbifera are traditional medicinal plants that can be considered as sources of natural antioxidants. Herein we report the phytochemical analysis and free radical scavenging activity of their sequential extracts. Phenolic and flavonoid content were determined. Scavenging activity was checked against pulse radiolysis generated ABTS•+ and OH radical, in addition to DPPH, superoxide and hydroxyl radicals by biochemical methods followed by principal component analysis. G. glauca leaf extracts were rich in phenolic and flavonoid content. Ethyl acetate extract of D. bulbifera bulbs and methanol extract of G. glauca stem exhibited excellent scavenging of pulse radiolysis generated ABTS•+ radical with a second order rate constant of 2.33×106 and 1.72×106, respectively. Similarly, methanol extract of G. glauca flower and ethyl acetate extract of D. bulbifera bulb with second order rate constants of 4.48×106 and 4.46×106 were found to be potent scavengers of pulse radiolysis generated OH radical. G. glauca leaf and stem showed excellent reducing activity and free radical scavenging activity. HPTLC fingerprinting, carried out in mobile phase, chloroform: toluene: ethanol (4: 4: 1, v/v) showed presence of florescent compound at 366 nm as well as UV active compound at 254 nm. GC-TOF-MS analysis revealed the predominance of diphenyl sulfone as major compound in G. glauca. Significant levels of n-hexadecanoic acid and octadecanoic acid were also present. Diosgenin (C27H42O3) and diosgenin (3á,25R) acetate were present as major phytoconstituents in the extracts of D. bulbifera. G. glauca and D. bulbifera contain significant amounts of phytochemicals with antioxidative properties that can be exploited as a potential source for herbal remedy for oxidative stress induced diseases. These results rationalize further investigation in the potential discovery of new natural bioactive principles from these two important medicinal plants. [ABSTRACT FROM AUTHOR]

Traditional remedies have a long-standing history in Cameroon and continue to provide useful and applicable tools for treating ailments. Here, the anticancer, antimicrobial and antioxidant activities of ten antioxidant-rich Cameroonian medicinal plants and of some of their isolated compounds are evaluated.The plant extracts were prepared by maceration in organic solvents. Fractionation of plant extract was performed by column chromatography and the structures of isolated compounds (emodin, 3-geranyloxyemodin, 2-geranylemodin) were confirmed spectroscopically. The antioxidant activity (AOA) was determined using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) bleaching method, the trolox equivalent antioxidant capacity (TEAC), and the hemoglobin ascorbate peroxidase activity inhibition (HAPX) assays. The anticancer activity was evaluated against A431 squamous epidermal carcinoma, WM35 melanoma, A2780 ovary carcinoma and cisplatin-resistant A2780cis cells, using a direct colorimetric assay. The total phenolic content in the extracts was determined spectrophotometrically by the Folin–Ciocalteu method. Rumex abyssinicus showed the best AOA among the three assays employed. The AOA of emodin was significantly higher than that of 3-geranyloxyemodin and 2-geranylemodin for both TEAC and HAPX methods. The lowest IC50 values (i.e., highest cytotoxicity) were found for the extracts of Vismia laurentii, Psorospermum febrifugum, Pentadesma butyracea and Ficus asperifolia. The Ficus asperifolia and Psorospermum febrifugum extracts are selective against A2780cis ovary cells, a cell line which is resistant to the standard anticancer drug cisplatin. Emodin is more toxic compared to the whole extract, 3-geranyloxyemodin and 2-geranylemodin. Its selectivity against the platinum-resistant A2780cis cell line is highest. All of the extracts display antimicrobial activity, in some cases comparable to that of gentamycin. [ABSTRACT FROM AUTHOR]

Traditional medicine caters for about 80% of the health care needs of many rural populations around the world, especially in developing countries. In addition, plant-derived compounds have played key roles in drug discovery. Malaria is currently a public health concern in many countries in the world due to factors such as chemotherapy faced by resistance, poor hygienic conditions, poorly managed vector control programmes and no approved vaccines. In this review, an attempt has been made to assess the value of African medicinal plants for drug discovery by discussing the anti-malarial virtue of the derived phytochemicals that have been tested by in vitro and in vivo assays. This survey was focused on pure compounds derived from African flora which have exhibited anti-malarial properties with activities ranging from "very active" to "weakly active". However, only the compounds which showed anti-malarial activities from "very active" to "moderately active" are discussed in this review. The activity of 278 compounds, mainly alkaloids, terpenoids, flavonoids, coumarines, phenolics, polyacetylates, xanthones, quinones, steroids, and lignans have been discussed. The first part of this review series covers the activity of 171 compounds belonging to the alkaloid and terpenoid classes.. Data available in the literature indicated that African flora hold an enormous potential for the development of phytomedicines for malaria. [ABSTRACT FROM AUTHOR]

Background: Calothamnus quadrifidus R.Br has many traditional uses and there are few reports about its chemical and biological activities. So our aim is to isolate the triterpenoidal compounds from dichloromethane fraction (DCMF) of Calothamnus quadrifidus R.Br leaves and in addition to evaluate the antibacterial activity of the isolated compounds. Methods: DCMF of C. quadrifidus leaves was subjected to different chromatographic techniques to isolate pure triterpenoidal compounds which were identified using different chemical and spectroscopic techniques. Antibacterial activities of the isolated compounds were evaluated using agar well diffusion method while minimum inhibitory concentration was assessed by microtiter plate assay method. Results: Five compounds were isolated and they were betulinic acid (1), ursolic acid (2), 3-acetyl-23-hydroxy betulinic acid (3), 2,23-dihydroxy betulinic acid (4) and 2,21,23-trihydroxy betulinic acid (5) were isolated from DCMF of C. quadrifidus leaves for the first time. Compounds 4 and 5 showed strong antibacterial activity against S. typhimurium while compound 4, 5 and 3, 4 exhibits moderate effect against E.coli and S. aureus respectively. Conclusion: Pure triterpenoidal compounds isolated from C. quadrifidus leaves showed antibacterial activities in different strengths. [ABSTRACT FROM AUTHOR]