Antibacterial effects of 18 medicinal plants used by the Khyang tribe in Bangladesh

Context: The resistance of bacteria to antibiotics is raising serious concern globally. Asian medicinal plants could improve the current treatment strategies for bacterial infections. The antibacterial properties of medicinal plants used by the Khyang tribe in Bangladesh have not been investigated.

Objective: The present study examines the antibacterial properties of 18 medicinal plants used by the Khyang tribe in day-to-day practice against human pathogenic bacteria.

Materials and methods: Leaves, bark, fruits, seeds, roots and rhizomes from collected plants were successively extracted with hexane, ethyl acetate and ethanol. The corresponding 54 extracts were tested against six human pathogenic bacteria by broth microdilution assay. The antibacterial mode of actions of phytoconstituents and their synergistic effect with vancomycin and cefotaxime towards MRSA was determined by time-killing assay and synergistic interaction assay, respectively.

Results and discussion: Hexane extract of bark of Cinnamomum cassia (L.) J. Presl. (Lauraceae) inhibited the growth of MRSA, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii with MIC values below 100 µg/mL. From this plant, cinnamaldehyde evoked at 4?×?MIC in 1?h an irreversible decrease of MRSA count Log10 (CFU/mL) from 6 to 0, and was synergistic with vancomycin for MRSA with fractional inhibitory concentration index of 0.3.

Conclusions: Our study provides evidence that the medicinal plants in Bangladesh have high potential to improve the current treatment strategies for bacterial infection.     

Ethnobotanical research of medicinal plants in Mihalgazi (Eskişehir,Turkey)

Context: Human beings have long utilized plants for medicinal purposes. Investigation of these plants has led to the discovery of several modern drugs.

Objective: This paper documents and evaluates traditional knowledge on medicinal plants used by the local people of Mihalgazi district of Eski?ehir, Turkey.

Materials and methods: Six villages of the study area were visited between February 2014 and April 2015 to collect the data. One hundred and eighty-nine informants were interviewed by the survey method and face to face semi-structured interviews. Taxonomic identification, the most commonly used plant parts, preparation and administration methods were evaluated. Ethnomedicinal data were analyzed quantitatively with relative importance (RI) and the informant consensus factor (FIC).

Results: This paper reported a total of 52 medicinal plants (37 wild, 15 cultivated) belonging to 34 families. Some uses of 22 plants were not found in the literature and are reported for the first time in this study. Furthermore, one of the plants, Calamagrostis arundinacea (L.) Roth (Poaceae), was reported for the first time as being used within the scope of traditional therapies.

Discussion and conclusion: This study recorded traditional knowledge on medicinal plants used in Mihalgazi, Turkey. This paper provides a basis for further investigations to discover efficient pharmaceuticals.     

The use of medicinal herbs in gynecological and pregnancy-related disorders by Jordanian women: a review of folkloric practice vs. evidence-based pharmacology

Context National statistical reports in Jordan indicate a decrease in the total fertility rate along with a parallel increase in contraceptive use. The folkloric use of medicinal herbs in gynecological disorders has been growing in Jordan, despite of deficient reports on the evidence-based safety and efficacy of these practices.

Objective The aim of this comprehensive article is to review medicinal plants with claimed ethnonpharmacological usage in various gynecological and pregnancy-related issues in Jordan, and to assess their evidence-based pharmacological studies as well as their phytochemistry.

Methods The published literature was surveyed using Google Scholar entering the terms “ethnopharmacology AND Jordan AND infertility AND gynecology OR gestation”. We included ethnopharmacological surveys in Jordan with available full-text.

Results Twelve articles were reviewed. Plant species which are commonly used for female gynecological issues such as Artemisia monosperma Del. and A. herba-alba Asso. (Asteraceae) have been found to exert an antifertility effect. Ricinus communis L. (Euphorbiaceae) and Citrullus colocynthis (L.) Schrad. (Cucurbitaceae) had antifertility effects in male rats, but Nigella sativa oil L. (Ranunculaceae) and Cinnamon zeylanicum J. Presl (Lauraceae) were found to enhance it.

Conclusion Using plants for gynecological disorders is a common practice in Jordan. Many of them, whether utilised for gynecological or non-gynecological conditions equally, were found to have detrimental effects on female or male fertility. Thus, couples planning pregnancy should be discouraged from the consumption of these herbs. Further local studies are warranted to confirm the appreciable beneficial pharmacological effects and safety of these plants.     

Chemical composition and biological activities of Helicteres vegae and Heliopsis sinaloensis

Context: Helicteres vegae Cristóbal (Sterculiaceae) (Hv) and Heliopsis sinaloensis B.L. Turner (Asteraceae) (Hs) are endangered and poorly studied plant species; related plants have been used against chronic-degenerative and infectious diseases. Therefore, Hv and Hs could be sources of bioactive compounds against these illnesses.

Objective: To determine the chemical composition and biological activities (antioxidant, antimutagenic and antimicrobial) of Hv and Hs leaves (L) and stems (S).

Materials and methods: Methanol extracts (ME) of each plant/tissue were evaluated for their phytochemicals; phenolics (HPLC-DAD-ESI-MS); antioxidant activity (AA) (0.125–4?mg/mL) (DPPH, ABTS, ORAC and β-carotene discoloration); antimutagenicity (0.5 and 1?mg/plate) (Ames assay, tester strain Salmonella enterica serovar Typhimurium YG1024, 1-nitropyrene as mutagen); activity against human pathogens (1?mg/mL); and toxicity (0.01–2?mg/mL) (Artemia salina assay).

Results: All ME showed flavonoids and triterpenes/steroids. The ME-SHv had the highest content of total phenolics (TP) (2245.82?±?21.45?mg GAE/100?g d.w.) and condensed tannins (603.71?±?1.115?mg CE/100?g d.w.). The compounds identified were flavonoids (kaempferol 7-O-coumaroylhexoside, and two kaempferol 7-O-rhamnosylhexosides) and phenolics [rosmarinic acid, and 3′-O-(8″-Z-caffeoyl) rosmarinic acid]. The ME-LHs showed the highest content of flavonoids (357.88?mg RE/g d.w.) and phenolic acids (238.58?mg CAE/g d.w.) by HPLC. The ME-SHv showed the highest AA. All ME were strong antimutagens (63.3-85.7%). Only the Hs extracts were toxic (ME-LHs, LC₅₀?=?94.9?±?1.7?μg/mL; ME-SHs, LC₅₀?=?89.03?±?4.42?μg/mL).

Discussion and conclusions: Both Hv and Hs are potential sources of preventive and therapeutic agents against chronic-degenerative diseases.     

Essential oil from fruit of Xylopia langsdorffiana: antitumour activity and toxicity

Context: The genus Xylopia L. (Annonaceae) includes aromatic plants that have both nutritional and medicinal uses. Essential oils of Xylopia species have antitumour effects. However, the efficacy of the essential oil from the fruit of Xylopia langsdorffiana St. Hil & Tul. (EOX) has not been examined.

Objective: EOX was evaluated to determine its chemical composition, antitumour activity and toxicity.

Materials and methods: EOX was obtained from fresh fruits of X. langsdorffiana subjected to hydrodistillation, and gas chromatography-mass spectrometry was used to characterize the chemical composition of EOX. The toxicity of EOX was evaluated using haemolysis, acute toxicity and micronucleus assays. The in vitro antitumour activity of EOX was investigated using the sulforhodamine B assay. The sarcoma 180 murine tumour model was used to evaluate the in vivo antitumour activity and toxicity of EOX (50 and 100?mg/kg) after 7 d of treatment.

Results: The major components of EOX were α-pinene (34.57%) and limonene (31.75%). The HC₅₀ (concentration producing 50% haemolysis) was 293.6?μg/ml. EOX showed greater selectivity for the leukaemia cell line K562, with total growth inhibition (TGI) (concentration producing TGI) of 1.8?μg/ml, and for multidrug-resistant ovarian tumour cell line NCI/ADR-RES (TGI of 45.4?μg/ml). The LD₅₀ was approximately 351.09?mg/kg. At doses of 50 and 100?mg/kg, EOX inhibited the in vivo growth of sarcoma 180 by 38.67 and 54.32%, respectively. EOX displayed minor hepatic alterations characteristic of acute hepatitis and induced no genotoxicity.

Conclusion: EOX showed in vitro and in vivo antitumour activity and low toxicity, which warrants further pharmacological studies.     

Plants used to treat skin diseases in northern Maputaland,South Africa: antimicrobial activity and in vitro permeability studies

Context: Ethnobotanical claims of medicinal plants used in northern Maputaland are limited.

Objectives To establish scientific validity for a selection of the plants used in Maputaland to treat skin diseases.

Materials and methods: Aqueous and dichloromethane–methanol extracts were prepared from 37 plant species which were collected from four rural communities in Maputaland. Antimicrobial screening was performed on extracts against 12 dermatological relevant pathogens using the micro-titre plate dilution assay. Their combined effect was evaluated by determining the sum of the fractional inhibitory concentrations (ΣFICs). Chemical analysis was undertaken using reverse-phase high-performance liquid chromatography (RP-HPLC) and investigated in vitro across excised intact porcine skin using the ILC07 automated system.

Results: The organic extract of Garcinia livingstonei T. Anderson (Clusiaceae) was found to be the most antimicrobially active displaying an average broad-spectrum MIC value of 270?μg/mL. The combination of Sclerocarya birrea (A. Rich.) Hotsch. (Anacardaceae) with Syzygium cordatum Hochst. ex C. Krauss (Myrtaceae) displayed synergistic effects. The four antimicrobially active organic extracts were found to possess mainly anthraquinones, flavonoids, tannins and saponins. The organic extracts of Kigelia africana (Lam.) Benth. (Bignoniaceae) and S. cordatum were found to have more compounds capable of permeating intact skin after 10?min of exposure.

Conclusion: More than 80% of the organic extracts tested displayed a correlation between the antimicrobial efficacy and the reported traditional uses of the plants. Furthermore, the traditional use of topically applied plant preparations is validated as some compounds from the active plants are capable of permeating the skin in vitro.     

To what extent are medicinal plants shared between country home gardens and urban ones? A case study from Misiones,Argentina

Context Worldwide ethnobotanical research has shown the importance of home gardens as sources of medicinal plants. These resources are worthy of further study in the Argentinean Atlantic Forest due to the richness of medicinal flora and their importance for local people.

Objective We studied richness, composition, cultural importance and medicinal uses of plants in home gardens of rural, semirural and urban areas in the Iguazú Department (Misiones, Argentina). Our hypothesis claims that people living in different environments have a similar array of medicinal plants in their gardens and they use them in a similar way.

Materials and methods The analysis was based on 76 interviews and plant inventories of home gardens. During guided walks in gardens, voucher specimens were collected. To analyse composition, Simpson similarity index was applied and a new index was proposed to measure culturally salient species.

Results All the environments had similar species composition with species differing in less than 30% of them. The most culturally salient taxa were Mentha spicata L. (Lamiaceae), in rural, Artemisia absinthium L. (Asteraceae), in semirural, and Aloe maculata All. (Xanthorrhoeaceae), in urban areas. The body systems treated with medicinal plants were similar across study sites.

Discussion The results suggest a “core repertoire” of medicinal plants and a widespread exchange of plants among local population. The cultural importance index informs us about plant adaptability, based on the efficacy and the versatility of medicinal resources.

Conclusion In this changing context where mobility and migrations constitute everyday life, medicinal plants in home gardens are part of local healthcare sovereignty.     

Antifungal Activity of Some Plant Extracts Against Fungal Pathogens of Tea (Camellia sinensis.)

Abstract

In an approach toward the development of ecofriendly antifungal compounds for controlling major foliar fungal diseases of tea, ethanol and aqueous extracts of 30 plants belonging to 20 different families collected from sub-Himalayan West Bengal (India) were tested against the pathogens Pestalotiopsis theae. (Saw.) Stey., Colletotrichum camelliae. Mess., Curvularia eragrostidis. (P. Hennings) Meyer, and Botryodiplodia theobromae. Patouiilard. Spore germination technique was followed for evaluation of antifungal properties. Results showed that ethanol and aqueous extracts of Allium sativum. L., Datura metel. L., Dryopteris filix-mas. (L.) Schott, Zingiber officinale. Rosc., Smilax zeylanica. L., Azadirachta indica., A. Joss. and Curcuma longa. L. recorded 100% inhibition of spore germination. The antifungal component from these plants may be used in developing novel fungicides for tea gardens.     

Botany of Tylophora indica (Burm. f.) Merr

Abstract

Tylophora indica (Burm. f.) Merr. is gaining importance in India, due to its anti-asthmatic properties. A short history of its introduction as an anti-asthmatic drug with important bibliography and citations, cultural trial and the botany of the cultured plants and the distribution are included. It is established that T. indica could easily be propogated by stem cutting and grown in the northern part of India.     

Evaluation of Antibacterial Activities of Medicinal Plants Widely Used Among AIDS Patients in Thailand

Abstract

Antibacterial activity of 12 selected Thai medicinal plants used as self-medication by HIV/AIDS patients in Thailand was studied. Thirty-nine chloroform, methanol, and aqueous extracts from these plants were investigated for their antibacterial activity against important pathogenic bacteria commonly associated with AIDS infection. These included Staphylococcus aureus., methicillin-resistant Staphylococcus aureus. (MRSA), Streptococcus mutans., and Salmonella typhi.. Inhibition of growth was tested using paper disk agar diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined by agar microdilution method and agar dilution method in Petri dishes with millipore filters. The Gram-positive bacteria were proved to be susceptible to the chloroform extracts of Alpinia galanga. (L.) Willd., Boesenbergia rotunda. Mansf. (L.), Piper betle. (L.), Spilanthes acmella. (L.) Murray, and Zingiber zerumbet. (L.) Roscoe ex Sm. and the methanol extract of Boesenbergia rotunda.. Chloroform extract of Alpinia galanga. demonstrated the greatest inhibition zones of 29.1 and 23.7 mm against Staphylococcus aureus. and MRSA, respectively. The MIC values of this extract against Staphylococcus aureus. and MRSA were 128 and 256 µg/ml and the MBC values were 256 and 256 µg/ml, respectively. An active compound, 1′-acetoxy-chavicol acetate, was identified with MIC values against MRSA and Staphylococcus aureus. of 64 and 128 µg/ml, respectively.     

Progress and prospects in the management of bacterial infections and developments in Phytotherapeutic modalities

The advent of antibiotics revolutionized medical care resulting in significantly reduced mortality and morbidity caused by infectious diseases. However, excessive use of antibiotics has led to the development of antibiotic resistance and indeed, the incidence of multidrug-resistant pathogens is considered as a major disadvantage in medication strategy, which has led the scholar's attention towards innovative antibiotic sources in recent years. Medicinal plants contain a variety of secondary metabolites with a wide range of therapeutic potential against the resistant microbes. Therefore, the aim of this review is to explore the antibacterial potential of traditional herbal medicine against bacterial infections. More than 200 published research articles reporting the therapeutic potential of medicinal plants against drug-resistant microbial infections were searched using different databases such as Google Scholar, Science Direct, PubMed and the Directory of Open Access Journals (DOAJ), etc., with various keywords like medicinal plants having antibacterial activities, antimicrobial potentials, phytotherapy of bacterial infection, etc. Articles were selected related to the efficacious herbs easily available to local populations addressing common pathogens. Various plants such as Artocarpus communis, Rheum emodi, Gentiana lutea L., Cassia fistula L., Rosemarinus officinalis, Argemone maxicana L, Hydrastis canadensis, Citrus aurantifolia, Cymbopogon citrates, Carica papaya, Euphorbia hirta, etc, were found to have significant antibacterial activities. Although herbal preparations have promising potential in the treatment of multidrug-resistant bacterial infection, still more research is required to isolate phytoconstituents, their mechanism of action as well as to find their impacts on the human body.     

Anti-Helicobactor pylori activity of some Jordanian medicinal plants

Context: Natural flora are considered a major source of new agents for the treatment of Helicobactor pylori. The plants used in this study were selected based on previous traditional use.

Objective: In this study, we evaluated the effect of extracts of 16 medicinal plants grown in Jordan against clinical isolates of H. pylori.

Materials and methods: Tested plant extracts included Aloysia triphylla (L'Her.) Britton (Verbenaceae), Anethum graveolens L. (Apiaceae), Artemisia inculata Delile (Asteraceae), Capparis spinosa L. (Capparaceae), Crataegus aronia (L.) Bosc ex. DC. (Rosaceae), Inula viscose (L.) Ait (Asteraceae), Lavandula officinalis Chaix. (Lamiaceae), Lepidium sativum L. (Cruciferae), Origanum syriaca L. (Lamiaceae), Paronychia argentea Lam. (Caryophyllaceae), Passiflora incarnate L. (Passifloraceae), Psidium guajava L. (Myrtaceae), Sarcopoterium spinosum (L.) Spach (Rosaceae), Sesamum indicum L. (Pedaliaceae), Urtica urens L. (Urticaceae) and Varthemia iphionoids Boiss (Asteraceae). Clinical isolates of H. pylori were tested in vitro for susceptibility to each of the above plant crude extracts using disk diffusion method, and the MIC value was determined for each plant extract using the serial dilution method.

Results: Results showed that ethanol extracts of most medicinal plants exerted cytotoxiciy against H. pylori isolates. Among the tested plant extracts, A. triphylla (MIC: 90?µg/mL, MBC: 125?µg/mL) and I. viscosa (MIC: 83?µg/mL, MBC: 104?µg/mL) showed the strongest activity against both isolates of H. pylori.

Discussion and conclusion: Jordanian medicinal plants might be valuable sources of starting materials for the synthesis of new antibacterial agents against H. pylori.     

三桠苦枝叶化学成分的分离、鉴定

目的 研究三桠苦[Evodia lepta（Spreng.）Merr.]枝叶的化学成分,为三桠苦的进一步研究奠定物质基础。方法 对三桠苦无水乙醇提取物的乙酸乙酯萃取物采用硅胶柱层析分离纯化,得到单体化合物,经波谱分析鉴定其化合物结构。结果 从三桠苦乙酸乙酯萃取物中分离得到6个单体化合物,分别为异吴茱萸酮酚（化合物1）、异吴茱萸酮酚甲醚（化合物2）、3,5-二羟基-4-乙氧基-6-乙酰基-7-甲氧基-2,2-二甲基苯并二氢吡喃（化合物3）、（cis）-3,4,5-三羟基-6-乙酰基-7-甲氧基-2,2-二甲基色烷（化合物4）和（trans）-3,4-二羟基-5-甲氧基-6-乙酰基-7-甲氧基-2,2-二甲基色烷（化合物5）和对羟基苯甲酸丁酯（化合物6）。结论 化合物1~6均为首次从三桠苦植物的枝叶中分离得到。     

Potent anti-proliferative effects against oral and cervical cancers of Thai medicinal plants selected from the Thai/Lanna medicinal plant recipe database “MANOSROI III”

Abstract

Context: Thai/Lanna medicinal plant recipes have been used for the treatment of several diseases including oral and cervical cancers.

Objective: To investigate anti-proliferative activity on human cervical (HeLa) and oral (KB) cancer cell lines of medicinal plants selected from Thai/Lanna medicinal plant recipe database “MANOSROI III”.

Materials and methods: Twenty-three methanolic plant crude extracts were tested for phytochemicals and anti-proliferative activity on HeLa and KB cell lines for 24?h by the sulforhodamine B (SRB) assay at the doses of 1?×?10¹–1?×?10^?6?mg/ml. The nine extracts with the concentrations giving 50% growth inhibition (GI₅₀) lower than 100?µg/ml were further semi-purified by liquid/liquid partition in order to evaluate and enhance the anti-proliferative potency.

Results: All extracts contained steroids/triterpenoids, but not xanthones. The methanolic extracts of Gloriosa superba L. (Colchinaceae) root and Albizia chinensis (Osbeck) Merr. (Leguminosae–Mimosoideae) wood gave the highest anti-proliferative activity on HeLa and KB cell lines with the GI₅₀ values of 0.91 (6.0- and 0.31-fold of cisplatin and doxorubicin) and 0.16?µg/ml (28.78- and 82.29-fold of cisplatin and doxorubicin), respectively. Hexane and methanol–water fractions of G. superba exhibited the highest anti-proliferative activity on HeLa and KB cell lines with the GI₅₀ values of 0.15 (37- and 1.9-fold of cisplatin and doxorubicin) and 0.058?µg/ml (77.45- and 221.46-fold of cisplatin and doxorubicin), respectively.

Discussion and conclusion: This study has demonstrated the potential of plants selected from MANOSROI III database especially G. superba and A. chinensis for further development as anti-oral and cervical cancer agents.     

Sesquiterpene lactones: Adverse health effects and toxicity mechanisms

Abstract

Sesquiterpene lactones (STLs) present a wide range of biological activities, mostly based on their alkylating capabilities, which underlie their therapeutic potential. These compounds are the active constituents of a variety of plants, frequently used as herbal remedies. STLs such as artemisinin and its derivatives are in use as first-line antimalarials while others, such as parthenolide, have recently reached cancer clinical trials. However, the toxicological profile of these compounds must be thoroughly characterized, since the same properties that make STL useful medicines can also cause severe toxicity. STL-containing plants have long been known to induce a contact dermatitis in exposed farm workers, and also to cause several toxic syndromes in farm animals. More recently, concerns are been raised regarding the genotoxic potential of these compounds and the embryotoxicity of artemisinins. A growing number of STLs are being reported to be mutagenic in different in vitro and in vivo assays. As yet no systematic studies have been published, but the genotoxicity of STLs seems to depend not so much on direct DNA alkylation as on oxidative DNA damage and other partially elucidated mechanisms. As the medicinal use of these compounds increases, further studies of their toxic potential are needed, especially those focusing on the structural determinants of genotoxicity and embryotoxicity.     

Selection of chemical markers for the quality control of medicinal plants of the genus Cecropia

Context: Several Cecropia (Cecropiaceae) species are traditionally used in Latin America for the treatment of a variety of diseases including diabetes, arterial hypertension, asthma, bronchitis, anxiety, and inflammation. At present, a number of commercial products based on these plants have been introduced into the market with very little information on methods for guaranteeing their quality and safety.

Objective: This work proposes potential chemical markers for the quality control of the raw materials of Cecropia obtusifolia Bertol., Cecropia peltata L., Cecropia glaziovii Snethl., Cecropia pachystachya Trécul, and Cecropia hololeuca Miq.

Methods: The Herbal Chemical Marker Ranking System (Herb MaRS) developed by the National Institute of Complementary Medicine (NICM) at the University of Western Sydney was used for selecting chemical markers for the quality control of selected medicinal species of Cecropia. This review covers the period from 1982 to 2016.

Results: Chlorogenic acid, flavonoidal glycosides (orientin, isoorientin, vitexin, isovitexin, and rutin), catechin, epicatechin, procyanidins (B2, B5, and C1), steroids (β-sitosterol), and triterpenoids (α-amyrin, pomolic, tormentic and ursolic acids) were selected as chemical markers for the quality control of the leaves.

Conclusion: It is necessary to establish comprehensive standards for guaranteeing quality, safety and efficacy of herbal drugs. The selection of adequate chemical markers for quality control purposes requires a good knowledge about the chemical composition of medicinal plants and their associated biological properties. To the best of our knowledge this review article is the first to address the identification and quantitative determination of the chemical markers for the genus Cecropia.     

中药青风藤的生药学研究

本文对中药青风藤的植物来源及生药鉴别等进行了较系统的研究。经实地调查与从全国收集标本分析,青风藤主要来源于3科7种植物,其中大多数地区所用均为防己科植物青藤Sinomenium acutum (Thunb.) Rehd. et Wils. 与毛青藤S. acutum (Thunb. )Kehd. et Wils. var. cinereum (Diels)Rehd. et Wils. 的藤茎。其它种应视为混淆品。并对青藤与毛青藤进行了原植物形态、生药性状、组织构造、理化鉴别,总生物碱含量等的比较研究,对青风藤其它数种混淆品进行了生药性状鉴别。     

Genotoxicity assessment through the Ames test of medicinal plants commonly used in Brazil

Ten medicinal herbs commonly used as popular medicine in Brazil—Bauhinia forficata L., Bauhinia variegata L., Cymbopogon citratus D.C. Stapf, Echinodorus macrophyllum (Kunth) Micheli, Hidrocotyle asiatica L, Matricaria chamomila L., Pfaffia iresinoides (Kunth) Sprengel, Plaffia paniculata (Martius) Kuntze, Phyllanthus tenellus Roxb, and Solidago microglossa D.C.—were tested for mutagenicity by the Ames test using Salmonella typhimurium TA 97a, TA 98, TA 100, and TA 104 strains, with and without metabolic activation. The genotoxicity assessment of these medicinal plants was performed in aqueous extracts 1:5. Seventy percent of these herbs presented mutagenic effects with at least one of the Ames strains used in this study. Bauhinia variegata L., E. macrophyllum K., and M. chamomilla L. showed no mutagenic activity. The mutagenic effects were detected mainly with the strains TA 98 related to frameshift mutations. The higher mutagenicity ratio was obtained with S. microglossa D.C. (known as arnica-do-Brazil) when TA 98 strain was used with metabolic activation (MR = 6.55) and with TA 97a strain with and without the addition of S9. Medicinal plants are now used by all the segments of the population, more intensively in the last years. These results indicate the need to establish rules to assess the safety of the use of medicinal herbs. © 1994 by John Wiley & Sons, Inc..     

Screening of Native Plants from Yucatan for Anti–Giardia lamblia. Activity

Abstract

The in vitro. activity of 10 methanol extracts prepared from native plants collected in the Yucatan Peninsula [Byrsonima crassifolia. (L.) Kunth, Cupania dentata. DC., Diphysa carthagenensis. Jacq., Dorstenia contrajerva. L., Gliricidia sepium. (Jacq.) Kunth ex Walp., Justicia spicigera. Schldl., Pluchea odorata. (L.) Cass., Spigelia anthelmia. L., Tridax procumbens. L., and Triumfetta semitriloba. Jacq.] was evaluated against Giardia lamblia. trophozoites. All the extracts showed activity against G. lamblia. trophozoites. T. procumbens. was most active, with an IC₅₀ of 6.34 µg/ml, followed by C. dentata., 7.59 µg/ml, D. carthagenensis., 11.53 µg/ml, and B. crassifolia., 15.55 µg/ml.     

Screening of plants of Amaryllidaceae and related families from Panama as sources of acetylcholinesterase inhibitors

Context: This is the first comprehensive study of the acetylcholinesterase (AChE) inhibitory activity of species of the family Amaryllidaceae and 13 related families from Panama.

Objective: Exploration of the potential sources of AChE inhibitors with radical scavenging activity from Amaryllidaceae and 13 related families from Panama.

Materials and methods: The studied plants were screened with anti-acetylcholinesterase bioautographic and DPPH free radical scavenging assays.

Results: From the 57 plants studied, eight (14%) showed strong inhibition of AChE, and 29 (51%) plants showed moderate inhibition of AChE.

Discussion and conclusion: Sagittaria lancifolia L. (Alismataceae), Crinum jagus (Thomps.) (Amaryllidaceae), Crinum x amabile Donn (Amaryllidaceae), Crinum zeylanicum (L.) L. (Amaryllidaceae), Crocosmia x crocosmiiflora (Lemoine ex Anonymous) N.E. Br. (Iridaceae), Sisyrinchium tinctorium Kunth (Iridaceae), Agapanthus praecox subsp. orientalis (F.M. Leight.) F.M. Leight. (Liliaceae), and Xyris jupicai Rich. (Xyridaceae) were the most active plants, inhibiting AChE at 100 μg on the TLC bioautographic method for the detection of acetylcholinesterase inhibitors. Out of the eight most active plants, two plants, Crinum zeylanicum (L.) L. and Xyris jupicai Rich., showed antioxidant activity.