Antibacterial Activity and Untargeted Metabolomics Profiling of Acalypha arvensis Poepp.

The search for potent antimicrobial compounds is critical in the face of growing antibiotic resistance. This study explores Acalypha arvensis Poepp. (A. arvensis), a Caribbean plant traditionally used for disease treatment. The dried plant powder was subjected to successive extractions using different solvents: hexane (F1), dichloromethane (F2), methanol (F3), a 50:50 mixture of methanol and water (F4), and water (F5). Additionally, a parallel extraction was conducted using a 50:50 mixture of methanol and chloroform (F6). All the fractions were evaluated for their antimicrobial activity, and the F6 fraction was characterized using untargeted metabolomics using SPME-GC×GC-TOFMS. The extracts of A. arvensis F3, F4, and F5 showed antibacterial activity against Staphylococcus aureus ATCC 25923 (5 mg/mL), MRSA BA22038 (5 mg/mL), and Pseudomonas aeruginosa ATCC 27853 (10 mg/mL), and fraction F6 showed antibacterial activity against Staphylococcus aureus ATCC 29213 (2 mg/mL), Escherichia coli ATCC 25922 (20 mg/mL), Pseudomonas aeruginosa ATCC 27853 (10 mg/mL), Enterococcus faecalis ATCC 29212 (10 mg/mL), Staphylococcus aureus 024 (2 mg/mL), and Staphylococcus aureus 003 (2 mg/mL). Metabolomic analysis of F6 revealed 2861 peaks with 58 identified compounds through SPME and 3654 peaks with 29 identified compounds through derivatization. The compounds included methyl ester fatty acids, ethyl ester fatty acids, terpenes, ketones, sugars, amino acids, and fatty acids. This study represents the first exploration of A. arvensis metabolomics and its antimicrobial potential, providing valuable insights for plant classification, phytochemical research, and drug discovery.

Phytochemical and Biological Study of Trophic Interaction between Pseudosphinx Tetrio L. Larvae and Allamanda Cathartica L.

In this article, we propose to explore the chemical interaction between Pseudosphinx tetrio L. and Allamanda cathartica L. using different analytical methods, including an innovative electrochemical approach (called electrochemical ecology) and multivariate analysis, and we investigate the potential antimicrobial effects (antibacterial and antifungal activities) of this interaction in order to gain a better understanding of their specific interaction. The analytical study presents a similar chemical profile between the leaves of healthy and herbivorous A. cathartica and the excretions of the caterpillars. The similar analytical profile of the leaves of A. cathartica and the excretions of P. tetrio, and the difference with the caterpillar bodies, suggests a selective excretion of compounds by the caterpillar. The measured antimicrobial activities support the physicochemical tests. The natural products found selectively in the excretions (rather than in the body) could explain the ability of P. tetrio to feed on this toxic Apocynaceae species.

Medicinal Plants and Plant-Based Remedies in Grande-Terre: An Ethnopharmacological Approach.

The island of Grande-Terre is a French overseas region that belongs to the Guadeloupean archipelago, a biodiversity hotspot with unique flora. Herbal medicine is widely used in the island for therapeutical purposes; however, there is a significant knowledge gap in the records relating to medicinal plants and their associated uses. Ethnobotanical survey methodology using quantitative parameters (informant consensus factor, species use value, relative frequency of citation, frequency use of a treatment and plant for an ailment) provided insights into the traditional medicinal use of a given plant. Ninety-six different plant species distributed among 56 families were identified and 523 remedies were documented in the survey. After data filtering, 22 plants species were associated with 182 remedies. The most frequent plant families were Poaceae, Myrtaceae, Cucurbitaceae and Rubiaceae. Aerial parts of these plants were the most common parts of the plant used for the remedies and the most frequent mode of administration was oral ingestion. This study highlights a valuable traditional knowledge of folklore medicine and helps to document and preserve the association of a plant with-and its use frequency for-a given ailment. These findings might be the starting point for the identification of biologically active phytocompounds to fight common health debilities.

The Metabolomic Profile of the Essential Oil from Zanthoxylum caribaeum (syn. chiloperone) Growing in Guadeloupe FWI using GC × GC-TOFMS.

The essential oil (EO) from the leaves of Zanthoxylum caribaeum (syn. Chiloperone) (Rutaceae) was studied previously for its acaricidal, antimicrobial, antioxidant, and insecticidal properties. In prior studies, the most abundant compound class found in leaf oils from Brazil, Costa Rica, and Paraguay was terpenoids. Herein, essential oil from the leaves of Zanthoxylum caribaeum (prickly yellow, bois chandelle blanc (FWI), peñas Blancas (Costa Rica), and tembetary hu (Paraguay)) growing in Guadeloupe was analyzed with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC × GC-TOFMS), and thirty molecules were identified. A comparison with previously published leaf EO compositions of the same species growing in Brazil, Costa Rica, and Paraguay revealed a number of molecules in common such as ß-myrcene, limonene, ß-caryophyllene, α-humulene, and spathulenol. Some molecules identified in Zanthoxylum caribaeum from Guadeloupe showed some antimetabolic effects on enzymes; the in-depth study of this plant and its essential oil with regard to metabolic diseases merits further exploration.

Antidiabetic Potential of Plants from the Caribbean Basin.

Diabetes mellitus (DM) is a group of metabolic disorders characterized by hyperglycemia, insulin insufficiency or insulin resistance, and many issues, including vascular complications, glycative stress and lipid metabolism dysregulation. Natural products from plants with antihyperglycemic, hypolipidemic, pancreatic protective, antioxidative, and insulin-like properties complement conventional treatments. Throughout this review, we summarize the current status of knowledge of plants from the Caribbean basin traditionally used to manage DM and treat its sequelae. Seven plants were chosen due to their use in Caribbean folk medicine. We summarize the antidiabetic properties of each species, exploring the pharmacological mechanisms related to their antidiabetic effect reported in vitro and in vivo. We propose the Caribbean flora as a source of innovative bioactive phytocompounds to treat and prevent DM and DM-associated complications.

Spectroscopic, Electrochemical, and Biological Assays of Copper-Binding Molecules for Screening of Different Drugs and Plant Extracts against Neurodegenerative Disorders.

Neurodegenerative disorders, caused by prone-to-aggregation proteins, such as Alzheimer disease or Huntington disease, share other traits such as disrupted homeostasis of essential metal ions, like copper. In this context, in an attempt to identify Cu2+ chelating agents, we study several organic compounds (ethylenediaminetetraacetic acid, phenylenediamine, metformin, salicylate, and trehalose) and organic extracts obtained from Bacopa monnieri L., which has been used in Ayurvedic therapies and presented a broad spectrum of biological properties. For this purpose, UV-visible spectroscopy analysis and electrochemical measurements were performed. Further, biological assays were performed in Caenorhabditis elegans models of polyQ toxicity, in an attempt to obtain better insights on neurodegenerative disorders.

Plant-Derived Pesticides as an Alternative to Pest Management and Sustainable Agricultural Production: Prospects, Applications and Challenges.

Pests and diseases are responsible for most of the losses related to agricultural crops, either in the field or in storage. Moreover, due to indiscriminate use of synthetic pesticides over the years, several issues have come along, such as pest resistance and contamination of important planet sources, such as water, air and soil. Therefore, in order to improve efficiency of crop production and reduce food crisis in a sustainable manner, while preserving consumer's health, plant-derived pesticides may be a green alternative to synthetic ones. They are cheap, biodegradable, ecofriendly and act by several mechanisms of action in a more specific way, suggesting that they are less of a hazard to humans and the environment. Natural plant products with bioactivity toward insects include several classes of molecules, for example: terpenes, flavonoids, alkaloids, polyphenols, cyanogenic glucosides, quinones, amides, aldehydes, thiophenes, amino acids, saccharides and polyketides (which is not an exhaustive list of insecticidal substances). In general, those compounds have important ecological activities in nature, such as: antifeedant, attractant, nematicide, fungicide, repellent, insecticide, insect growth regulator and allelopathic agents, acting as a promising source for novel pest control agents or biopesticides. However, several factors appear to limit their commercialization. In this critical review, a compilation of plant-derived metabolites, along with their corresponding toxicology and mechanisms of action, will be approached, as well as the different strategies developed in order to meet the required commercial standards through more efficient methods.

The essential oil of Populus balsamifera buds: its chemical composition and cytotoxic activity.

The chemical composition of Populus balsamifera essential oils obtained from spring buds, fall buds, and young leaves were determined by GC and GC-MS analyses. The major constituent, (+)-alpha-bisabolol, a rare sesquiterpene, was isolated from spring oil using reverse-phase preparative HPLC. The cytotoxic activity of balsam poplar oils and isolated (+)-alpha-bisabolol was assessed in vitro against human lung carcinoma (A549) and colorectal adenocarcinoma (DLD-1) cell lines. Essential oils were cytotoxic with IC50 ranging from 35 to 50 microg/mL. (+)-alpha-Bisabolol exhibited pronounced activity (IC50 14 microg/mL) against both cancer cell lines. It also exhibited interesting cytotoxic activity (IC50 23 microg/mL) against human glioma (U251), higher than the one observed for (-)-alpha-bisabolol (IC50 34 microg/mL), which is known for its apoptosis-inducing effect against glioma cells.

Composition and cytotoxic activity of the leaf essential oil of Comptonia peregrina (L.) Coulter.

Comptonia peregrina (L.) Coulter, a native plant from Canada used in traditional medicine against cancer, was extracted by hydrodistillation. Two fractions were collected, one over 0-30 min and one over 30-60 min, to assess the influence of time of hydrodistillation on the composition of essential oil. The chemical composition of these two extracts was determined by GC and GC-MS analyses. Fifty five components were identified: beta-caryophyllene (23.69% and 15.16%) and alpha-humulene (9.67% and 7.43%) were the major components in the 0-30 min and 30-60 min fractions, respectively, while beta-myrcene was detected in a higher amount in the 0-30 min fraction (12.58%) than in the 30-60 min fraction (0.15%). The cytotoxic activities of these fractions were assessed against human lung carcinoma cell line A-549 and human colon adenocarcinoma cell line DLD-1. Only the 30-60 min fraction was found to be active against both tumor cell lines, with GI(50) values of 66 +/- 12 microg/mL for A-549 and of 46 +/- 7 microg/mL for DLD-1. Two sesquiterpenes present in the oil, alpha-humulene and (E)-nerolidol, have been found to be cytotoxic against both tumor cell lines.

Ketosteroids and hydroxyketosteroids, minor metabolites of sugarcane wax.

Besides beta-sitosterol and stigmasterol, the major steroids of sugarcane, the following minor steroids have been isolated and identified from sugarcane wax: 3,6-diketosteroids, Delta(4)-3-keto steroids, and Delta(4)-6-hydroxy-3-keto steroids. Their structures were established by spectroscopic techniques and chemical correlations.

Essential oil analysis and anticancer activity of leaf essential oil of Croton flavens L. from Guadeloupe.

The leaf essential oil of Croton flavens L., a native plant from the Caribbean area used in traditional medicine, was extracted by hydrodistillation. The composition of the volatile fraction of this essential oil was determined by GC and GC-MS analyses. We have identified 47 compounds, of which viridiflorene (12.22%), germacrone (5.27%), (E)-gamma-bisabolene (5.25%) and beta-caryophyllene (4.95%) are the main components. The anticancer activity of this extract was tested on human lung carcinoma cell line A-549 and human colon adenocarcinoma cell line DLD-1. Croton flavens leaf essential oil was found to be very active against both tumor cell lines, with a GI(50) of 27 +/- 4 microg/ml for A-549 and 28 +/- 3 microg/ml for DLD-1. Three compounds identified in the leaf essential oil, alpha-cadinol (3.97%), beta-elemene (1.53%) and alpha-humulene (1.06%) are cytotoxic against tumor cell lines.