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This review describes an Indigenous-led project run by Q'eqchi' Maya Healers of Belize meant to strengthen and improve traditional botanical healing. The goals of this project were to conserve medicinal plant knowledge by way of ethnobotanical studies, and to conserve the plants themselves by creating a community ethnobotanical garden. A total of 169 medicinal species were collected in the ethnobotanical survey, which provided unique knowledge on many rainforest species of the wet lowland forest of southern Belize, not found in neighbouring Indigenous cultures. Consensus on plant uses by the Healers was high, indicating a well-conserved, codified oral history. After horticultural experimentation by the Healers, the Indigenous botanical garden provided a habitat for and conservation of 102 medicinal species including many epiphytes that were rescued from forested areas. Ethnopharmacological studies by the university partners showed a pharmacological basis for, and active principles of, plants used for epilepsy and anxiety, for inflammatory conditions such as arthritis, for dermatological mycoses, and for type 2 diabetes complications. Overall, the project has provided a model for Indigenous empowerment and First Nation's science, as well as establishing traditional medicine as an important, unified healing practice that can safely and effectively provide primary health care in its cultural context. Key words: ethnobotany, ethnopharmacology, Q'eqchi' Maya, Mesoamerican flora, Belize. Cette revue décrit un projet mené par des guérisseurs mayas Q'eqchi' de Xna'ajeb' aj Ralch'o'och' (Belize) pour renforcer et améliorer la médecine botanique traditionnelle. Les objectifs du projet étaient de conserver les connaissances sur les plantes médicinales, ce qui a conduit à des études ethnobotaniques, et de conserver les plantes elles-mêmes, en créant un jardin ethnobotanique dirigé par la communauté. Au total, 169 espèces médicinales ont été collectées dans le cadre de l'ethnobotanique, ce qui a permis d'acquérir des connaissances uniques sur de nombreuses espèces de la forêt pluviale des basses terres humides du sud du Belize, que l'on ne trouve pas dans les cultures indigènes voisines. Le consensus sur l'utilisation des plantes par les guérisseurs était élevé, ce qui indique une histoire orale codifiée bien conservée. Après l'expérimentation horticole des guérisseurs, le jardin botanique indigène a permis d'abriter et de conserver 102 espèces médicinales, dont de nombreux épiphytes provenant de zones forestières. Des études ethnopharmacologiques menées par les partenaires universitaires ont mis en évidence la base pharmacologique et les principes actifs de plantes utilisées pour traiter l'épilepsie et l'anxiété, les états inflammatoires tels que l'arthrite, les mycoses dermatologiques et les complications du diabète de type 2. Dans l'ensemble, le projet a fourni un modèle pour l'autonomisation des autochtones et la science des Premières nations, tout en établissant cette médecine traditionnelle comme une pratique de guérison importante et unifiée, qui peut fournir en toute sécurité et efficacement des soins de santé primaires dans son contexte culturel. Mots-clés : ethnobotanique, ethnopharmacologie, Mayas Q'eqchi', flore mésoaméricaine, Belize., B'antyox re loq'lajChoxaa ut li loqlajCh'och' jo'kanajwi' naqab'antyoxireheb' li qasqitz'inhaneb' xmuhileb' wankchikcho'oqIq', ha', kutanitch'o'ocheb' chikhaneb'eb chikajK'amalb'eheb' re qachab'iltyuham... Thanks to the Hearth of Heaven and Hearth of Earth and to [...]

The Marcgraviaceae is a neotropical plant family of lianas and shrubs distributed throughout Central and South America, mainly in evergreen and semi-evergreen tropical forests. In this study, extracts of 12 Marcgraviaceae species were assessed for inhibition of bacterial quorum sensing (QS) in Chromobacterium violaceum, bacterial biofilm formation in Pseudomonas aeruginosa PA14, and fungal growth in Saccharomyces cerevisiae. Six species showed promising inhibitory activities in at least one of the three bioassays (Marcgravia nervosa Triana & Planch., Marcgravia polyantha Delp., Marcgravia schippii Standl., Marcgraviastrum subsessile (Benth.) Bedell, Schwartzia brasiliensis (Choisy) Bedell ex Gir-Canas, and Schwartzia costaricensis (Gilg.) Bedell). Analyses of the crude extract of the leaves of Marcgravia nervosa using HPLC-APCI-MS showed the presence of five pentacyclic triterpenes: ursolic acid (2), betulinic acid (3), [alpha]-amyrin (4), [beta]-amyrin (5), lupeol (6). Bioassay-guided fractionation of this plant resulted in the isolation and identification of 2-methoxy-1,4-naphthoquinone (1) as the active principle with a minimum inhibitory concentration (MIC) of 85-100 [micro]mol x [L.sup.-1] against Saccharomyces cerevisiae BY4741 (haploid) and BY4743 (diploid). Key words: Marcgraviaceae, Marcgravia nervosa, quorum sensing, biofilm, antifungal, naphthoquinone. Les Marcgraviaceae constituent une famille neotropicale de lianes et d'arbustes distribuee a travers l'Amerique Centrale et l'Amerique du Sud, principalement dans les forets tropicales sempervirentes et semi-sempervirentes. Dans cette etude, des extraits de 12 especes de Marcgraviaceae ont ete evalues quant a leur activite inhibitrice de detection de quorum (DQ) bacterien chez Chromobacterium violaceum, de la formation de biofilm chez Pseudomonas aeruginosa PA14 et de la croissance fongique chez Saccharomyces cerevisiae. Six especes ont montre des activites inhibitrices prometteuses dans au moins un des trois essais biologiques (Marcgravia nervosa Triana & Planch., Marcgravia polyantha Delp., Marcgravia schippii Standl., Marcgraviastrum subsessile (Benth.) Bedell, Schwartzia brasiliensis (Choisy) Bedell ex Gir-Canas et Schwartzia costaricensis (Gilg.) Bedell). Des analyses d'extraits bruts de feuilles de Marcgravia nervosa par HPLC-APCI-MS ont montre la presence de cinq triterpenes pentacycliques : l'acide ursolique (2), l'acide betulinique (3), l'[alpha]-amyrine (4), la [beta]-amyrine (5) et le lupeol (6). Le fractionnement de cette plante guide par les essais biologiques a resulte en l'isolement et l'identification de la 2-methoxy-1,4-naphthoquinone (1) comme principe actif possedant une concentration inhibitrice minimale (CIM) de 85-100 [micro]mol x [L.sup.-1] envers Saccharomyces cerevisiae BY4741 (haploide) et BY4743 (diploide). [Traduit par la Redaction] Mots-cles : Marcgraviaceae, Marcgravia nervosa, detection de quorum, biofilm, antifongique, naphthoquinone., Introduction The Marcgraviaceae is a neotropical plant family of lianas and shrubs consisting of seven genera and 130 species distributed throughout Central and South America, mainly in evergreen and semi-evergreen [...]

Microbial biofilms readily form on many surfaces in nature including plant surfaces. In order to coordinate the formation of these biofilms, microorganisms use a cell-to-cell communication system called quorum sensing (QS). As formation of biofilms on vascular plants may not be advantageous to the hosts, plants have developed inhibitors to interfere with these processes. In this mini review, research papers published on plant-derived molecules that have microbial biofilm or quorum sensing inhibition are reviewed with the objectives of determining the biosynthetic classes of active compounds, their biological activity in assays, and their families of occurrence and range. The main findings are the identification of plant phenolics, including benzoates, phenyl propanoids, stilbenes, flavonoids, gallotannins, proanthocyanidins and coumarins as important inhibitors with both activities. Some terpenes including monoterpenes, sesquiterpenes, diterpenes and triterpenes also have anti-QS and anti-biofilm activities. Relatively few alkaloids were reported. Quinones and organosulfur compounds, especially from garlic, were also active. A common feature is the polar nature of these compounds. Phytochemicals with these activities are widespread in Angiosperms in temperate and tropical regions, but gymnosperms, bryophytes and pteridophytes were not represented.

Bacterial biofilms are responsible for many persistent infections by many clinically relevant pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa. Biofilms are much more resistant to conventional antibiotics than their planktonic counterparts. Quorum sensing, an intercellular communication system, controls pathogenesis and biofilm formation in most bacterial species. Quorum sensing provides an important pharmacological target since its inhibition does not provide a selective pressure for resistance. In this study, we investigated the quorum sensing and biofilm inhibitory activities of 126 plant extracts from 71 species collected from neotropical rainforests in Costa Rica. Quorum sensing and biofilm interference were assessed using a modified disc diffusion bioassay with Chromobacterium violaceum ATCC 12,472 and a spectrophotometric bioassay with Pseudomonas aeruginosa PA14, respectively. Species with significant anti-quorum sensing and/or anti-biofilm activities belonged to the Meliaceae, Melastomataceae, Lepidobotryaceae, Sapindaceae, and Simaroubaceae families. IC50 values ranged from 45 to 266 µg/mL. Extracts of these active species could lead to future development of botanical treatments for biofilm-associated infections., (Georg Thieme Verlag KG Stuttgart · New York.)

Here we show for the first time that components of pulp and paper mill effluents contain neuroactive substances that may impair fish reproduction. Grab samples of primary and secondary effluent were obtained from a representative pulp and paper mill in Eastern Canada. Effluents were fractionated using classic polarity and polyphenolic extraction methods into solvents of selected polarities (water, ethanol, ethyl acetate, and hexane). By means of in vitro, competitive assays on goldfish (Carassius auratus) brain tissues, the extracts were screened for their ability to interact with enzymes and receptors involved in gamma-aminobutyric acid (GABA), dopamine, glutamate, and acetylcholine-dependent neurotransmission. These neurotransmission pathways have essential regulatory roles in fish reproduction. Radioligand binding to the following neurotransmitter receptors were significantly impacted following in vitro incubations with extracts (percentage change from controls indicated in brackets): dopamine-2 (D2; 21-48% increase), GABA(A) receptor binding (65-67% decrease and 189% increase), N-methyl-o-aspartic acid (NMDA; 26-75% decrease), and muscarinic cholinergic (mACh; 42% increase). Activities of the following neurotransmitter-related enzymeswere significantly impacted: monoamine oxidase (MAO; 14-48% decrease), GABA-transaminase activity (33% decrease and 21-69% increase), and acetylcholinesterase (AChE; 21-50% decrease). No changes in glutamic acid decarboxylase (GAD) activity were detected. These findings provide a novel and plausible mechanism by which pulp and paper mills effluents impair fish reproduction by interacting with neurotransmitter systems. Furtherwork is required to identify the active compounds and explore whether these changes occur in vivo.

Diabetic hyperglycaemia promotes the production of advanced glycation end-products (AGEs), which play a significant role in the development of complications associated with type 2 diabetes mellitus. Vaccinium angustifolium, a medicinal plant used for the treatment of diabetes, produces a variety of phenolic metabolites with putative anti-diabetic activities. To assess optimal cultivation time, seasonal changes in the concentration of six phenolic compounds in leaves and twelve compounds in stems were examined using HPLC-DAD and examined in relation to seasonal changes in AGE inhibition activity, assessed with a fluorescence-based assay. A seasonal decline occurred in the concentration of chlorogenic acid, rutin, and quercetin 3-arabinoside in leaves and chlorogenic acid in stems. The concentration of (+)-catechin, and (-)-epicatechin in stems declined within two weeks before rising and fluctuating insignificantly. AGE inhibition activity of leaves was significantly greater at the final compared to the initial collection date whereas the activity of stems did not change significantly. Relative to the leaf extract, the stem was a more potent inhibitor of AGE formation, which could be a result of the unique phytochemistry of stems. Together, these results revealed significant seasonal variation in the phenolic profile and anti-glycation effects of V. angustifolium extracts and indicated late summer as the collection time yielding optimal activity.

Gas chromatography analysis of the essential oils of leaves and bark collected from the newly discovered tree Pleodendron costaricense identified alpha-pinene, beta-pinene, beta-myrcene, beta-thujene, and beta-caryophyllene as their major constituents. Phytochemical analysis of P. costaricense parts led to the isolation and identification of delta-tocotrienol, beta-sitosterol, four known drimane-type sesquiterpenes, cinnamodial (1), cinnamosmolide (2), polygodial (3), and mukaadial (4), and two new compounds, a drimane-type sesquiterpene, parritadial (5), and an eremophilane-type sesquiterpene, pleodendione (6). Antifungal assays with the two major compounds, 1 and 2, were carried out, and results showed a high activity of 1 against Alternaria alternata (MIC = 3.9 microg/mL), Candida albicans azole-resistant strain D10, and Wangiella dermatitides (MICs = 15.6 microg/mL). Compound 2 showed less potent antifungal activities than 1 but was more effective against Candida albicans azole-resistant strain CN1A (MIC = 23.4 microg/mL) and Pseudallescheria boydii (MIC = 78.1 microg/mL). A combination of the dialdehyde sesquiterpenes with dillapiol showed a synergistic antifungal effect with 1 and an additive effect with 4 and 5.