Influencia de la edad en el contenido de fenoles y ligninas en Gmelina arborea (Lamiaceae) / The influence of age on the phenolic contents and lignins of Gmelina arborea (Lamiaceae)

Resumen Introducción: La melina (Gmelina arborea), es una especie de gran interés por su madera y propiedades medicinales. En Costa Rica, existen clones genéticamente superiores que se propagan sin el conocimiento de la edad ontogénica y fisiológica de los materiales. Objetivo: Evaluar la relación del contenido de fenoles y ligninas en hojas, peciolos, tallos y raíces de plantas con diferentes edades. Métodos: Los contenidos de fenoles y ligninas totales se determinaron mediante el método colorimétrico de Folin-Ciocalteu y el método de extracción alcalina, respectivamente. Para la investigación se eligieron plantas in vitro "año cero" y árboles de año y medio, cuatro, siete y 20 años. El muestreo se realizó en marzo y abril del 2021. Resultados: Se demostró que todas las partes de la planta analizadas contienen compuestos fenólicos y ligninas, independientemente de su edad. No hubo una correlación positiva entre la edad con el contenido de fenoles y ligninas para ninguna condición de desarrollo, pues los valores más altos no se obtuvieron en los árboles más longevos. Los extractos de hojas de las plantas in vitro y los árboles de siete años mostraron, respectivamente, los contenidos más altos de fenoles y ligninas para todas las condiciones (P < 0.05). Los valores promedio más bajos de compuestos fenólicos para todas las condiciones se obtuvieron en los árboles de cuatro años. Respecto a las ligninas, el contenido más bajo se presentó en las raíces más longevas, aunque la tendencia no se mantuvo para el resto de las partes de la planta. Conclusiones: La investigación muestra los primeros resultados del contenido de compuestos fenólicos y ligninas presentes en diferentes tejidos de una especie forestal de edades diferentes. Por lo tanto, son los primeros valores de referencia acerca del compromiso bioquímico para la síntesis fenólica según la edad y el estado de desarrollo específico de una planta leñosa.

Abstract Introduction: Melina (Gmelina arborea) is a tree species of great interest for its wood and medicinal properties. In Costa Rica, there are genetically superior clones that are propagated without knowledge of the ontogenic and physiological age of the materials. Objective: To evaluate how age influences the content of phenols and lignins in leaves, petioles, stems, and roots of melina plants. Methods: The total phenolic and lignins contents were determined using Folin-Ciocalteu colorimetric method and alkaline extraction method, respectively. Plants of five different ages were chosen for the investigation (in vitro plants "year 0" and trees of a year and a half, four, seven and 20 years). Sampling was done in March and April 2021. Results: All parts of the plant analyzed contain phenolic compounds and lignins, regardless of their age. There was no positive correlation between age and phenol and lignin content for any development condition, since the highest values were not obtained in the oldest trees. Leaf extracts from in vitro plants and seven-year-old trees showed, respectively, the highest phenol and lignin contents for all conditions (P < 0.05). The lowest average values of phenolic compounds for all conditions were obtained in four-year-old trees. Regarding lignins, the lowest content occurred in the oldest roots, although the trend was not maintained for the rest of the plant parts. Conclusions: This study provides the first results of the content of phenolic compounds and lignins present in different tissues of a forest species of different ages. Therefore, they are the first reference values about the biochemical commitment for phenolic synthesis according to the age and the specific developmental stage of a woody plant.

Phytochemical and antimicrobial evaluation of Miconia burchellii Triana (Melastomataceae).

Four novel triterpenoid saponins, 1α,3ß,23-trihydroxy-olean-12-en-28-oic acid 28-O-ß-glycopyranoside ester (1), 1α,3ß,23-trihydroxy-urs-12-en-28-oic acid 28-O-ß-glycopyranoside ester (2), 3-O-ß-galloyl-1α,23-dihydroxy-olean-12-en-28-oic acid 28-O-ß-glycopyranoside ester (3) and 3-O-ß-galloyl-1α,23-dihydroxy-urs-12-en-28-oic acid 28-O-ß-glycopyranoside ester (4) and two new pentacyclic triterpenoids, 3-O-ß-trans-p-coumaroyl-1α-hydroxy-urs-12-en-28-oic acid (5) and 3-O-ß-cis-p-coumaroyl-1α-hydroxy-urs-12-en-28-oic acid (6), together with six known compounds were isolated from the ethanolic extracts of Miconia burchellii leaves and stem bark. Their structures were established by HR-MS, 1D and 2D NMR and comparison with literature data. Additionally, the antimicrobial activity of the leaves and stem bark extracts and fractions was evaluated using the micro broth dilution technique. The crude extract, the ethyl acetate and methanol fractions of the stem bark were the most active against the tested bacteria, showing growth inhibition of both Gram-positive (Staphylococcus aureus and Staphylococcus epidermidis) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa). To the best of our knowledge, this is the first study to report on the antimicrobial activity of M. burchellii.

Secondary metabolites with antimicrobial activity produced by thermophilic bacteria from a high-altitude hydrothermal system.

Thermophilic microorganisms possess several adaptations to thrive in high temperature, which is reflected as biosynthesis of proteins and thermostable molecules, isolation and culture represent a great methodological challenge, therefore High throughput sequencing enables screening of the whole bacterial genome for functional potential, providing rapid and cost-effective information to guide targeted cultures for the identification and characterization of novel natural products. In this study, we isolated two thermophilic bacterial strains corresponding to Bacillus LB7 and Streptomyces LB8, from the microbial mats in the Atacama Desert. By combining genome mining, targeted cultures and biochemical characterization, we aimed to identify their capacity to synthesize bioactive compounds with antimicrobial properties. Additionally, we determined the capability to produce bioactive compounds under controlled in vitro assays and detected by determining their masses by Thin-Layer Chromatography/Mass Spectrometry (TLC/MS). Overall, both isolates can produce antimicrobial (e.g., Myxalamide C by-product) and antioxidants (e.g. Dihydroxymandelic Acid, Amide biotine and Flavone by-products) compounds. Bacillus LB7 strain possesses a more diverse repertoire with 51.95% of total metabolites unmatched, while Streptomyces LB8 favors mainly antioxidants, but has over 70% of unclassified compounds, highlighting the necessity to study and elucidate the structure of novel compounds. Based on these results, we postulate that the uncultured or rare cultured thermophiles inhabiting high-altitude hydrothermal ecosystems in the Atacama Desert offer a promising opportunity to the study of novel microbial bioactive compounds.

Impact of External Sources of Indole Acetic Acid and 2,3,5-Triiodobenzoic Acid on Alkaloid Production and Their Relationships with Primary Metabolism and Antioxidant Activity in Annona emarginata (Schltdl.) H. Rainer.

Annona emarginata is a native Brazilian species capable of producing at least ten alkaloids of ecological, agronomic, and pharmacological importance. Some studies have explored the effect of external phytoregulators on the production of alkaloids, including the effect of auxins, which, like alkaloids, derive from the shikimic acid pathway. Thus, this study aimed to evaluate how indole acetic acid (IAA) and its inhibitor 2,3,5-triiodobenzoic acid (TIBA) impact the production of alkaloids and the primary metabolism of A. emarginata, which brings advances in the understanding of the mechanisms of alkaloid synthesis and can aid in the bioprospection of molecules of interest in Annonaceae. The design was completely randomized, with three treatments (control, IAA [10-6 M] and TIBA [10-6 M]) and five collection times (12, 36, 84, 156, and 324 h). The following variables were analyzed: total alkaloids, alkaloid profile, nitrate reductase activity, gas exchange in photosynthesis, chlorophyll a fluorescence, sugars, starch, and antioxidant activity. Of the twelve alkaloids analyzed, discretine and xylopine were not detected in the control plants; however, both were detected when IAA was applied (in roots and leaves) and xylopine (in roots) when the inhibitor was applied. The alkaloid asimilobine was not detected with the use of TIBA. Variations in alkaloid concentrations occurred in a punctual manner, without significant variations in photosynthesis and nitrate reductase activity, but with variations in the antioxidant system and sugar concentrations, mainly at 156 h, when the highest alkaloid concentrations were observed with the use of TIBA. It could be concluded that IAA is capable of selectively modulating the production of alkaloids in A. emarginata, either due to an external source or by the application of its inhibitor (TIBA).

Exploration of diverse secondary metabolites from Penicillium brasilianum by co-culturing with Armillaria mellea.

Bioinformatic analysis revealed that the genomes of ubiquitous Penicillium spp. might carry dozens of biosynthetic gene clusters (BGCs), yet many clusters have remained uncharacterized. In this study, a detailed investigation of co-culture fermentation including the basidiomycete Armillaria mellea CPCC 400891 and the P. brasilianum CGMCC 3.4402 enabled the isolation of five new compounds including two bisabolene-type sesquiterpenes (arpenibisabolanes A and B), two carotane-type sesquiterpenes (arpenicarotanes A and B), and one polyketide (arpenichorismite A) along with seven known compounds. The assignments of their structures were deduced by the extensive analyses of detailed spectroscopic data, electronic circular dichroism spectra, together with delimitation of the biogenesis. Most new compounds were not detected in monocultures under the same fermentation conditions. Arpenibisabolane A represents the first example of a 6/5-fused bicyclic bisabolene. The bioassay of these five new compounds exhibited no cytotoxic activities in vitro against three human cancer cell lines (A549, MCF-7, and HepG2). Moreover, sequence alignments and bioinformatic analysis to other metabolic pathways, two BGCs including Pb-bis and Pb-car, responsible for generating sesquiterpenoids from co-culture were identified, respectively. Furthermore, based on the chemical structures and deduced gene functions of the two clusters, a hypothetic metabolic pathway for biosynthesizing induced sesquiterpenoids was proposed. These results demonstrated that the co-culture approach would facilitate bioprospecting for new metabolites even from the well-studied microbes. Our findings would provide opportunities for further understanding of the biosynthesis of intriguing sesquiterpenoids via metabolic engineering strategies. KEY POINTS: • Penicillium and Armillaria co-culture facilitates the production of diverse secondary metabolites • Arpenibisabolane A represents the first example of 6/5-fused bicyclic bisabolenes • A hypothetic metabolic pathway for biosynthesizing induced sesquiterpenoids was proposed.

Essential oil components interacting with insect odorant-binding proteins: a molecular modelling approach.

Essential oils (EOs) are natural products currently used to control arthropods, and their interaction with insect odorant-binding proteins (OBPs) is fundamental for the discovery of new repellents. This in silico study aimed to predict the potential of EO components to interact with odorant proteins. A total of 684 EO components from PubChem were docked against 23 odorant binding proteins from Protein Data Bank using AutoDock Vina. The ligands and proteins were optimized using Gaussian 09 and Sybyl-X 2.0, respectively. The nature of the protein-ligand interactions was characterized using LigandScout 4.0, and visualization of the binding mode in selected complexes was carried out by Pymol. Additionally, complexes with the best binding energy in molecular docking were subjected to 500 ns molecular dynamics simulations using Gromacs. The best binding affinity values were obtained for the 1DQE-ferutidine (-11 kcal/mol) and 2WCH-kaurene (-11.2 kcal/mol) complexes. Both are natural ligands that dock onto those proteins at the same binding site as DEET, a well-known insect repellent. This study identifies kaurene and ferutidine as possible candidates for natural insect repellents, offering a potential alternative to synthetic chemicals like DEET.

Cupuaçu (Theobroma grandiflorum): A Multifunctional Amazonian Fruit with Extensive Benefits.

The Amazon region is known for its continental dimension, water abundance, and especially for the rich biodiversity that this biome hosts. Among the thousands of plant species in the Amazon, many represent food sources. Among these, cupuaçu (Theobroma grandiflorum (Willd. ex Spreng.) K.Schum.) stands out as an iconic fruit with an exotic flavor, appreciated for its remarkable organoleptic properties. The present review aims to provide a comprehensive description of its biology, agronomical uses, nutritional values, chemical compositions, medicinal properties, and industrial applications. The search based on scientific articles demonstrates T. grandiflorum as a valuable ingredient for the food, cosmetic and pharmaceutical sectors. Data analysis demonstrates that cupuaçu cultivation and processing contribute to the strengthening of local production chains and promotes the development of small communities, and thus the bioeconomy in the Amazon region. In this sense, since the last decade, cultivar improvement has required multidisciplinary efforts, resulting in disease-resistant plants with better productivity. Regarding its chemical composition, T. grandiflorum is a notable source of methylxanthine alkaloids, polyphenols, aroma compounds, and lipids. The presence of these compounds supports the use of cupuaçu in various products and help us to understand the potential health benefits of its consumption. Through the integration of all collected information, key gaps in basic and applied sciences were observed, highlighting the need for more research to uncover novel applications and products of T. grandiflorum. The development of new products based on biodiversity is fundamental to promoting environmental and economic sustainability, which are key steps to the survival of the Amazon rainforest. Therefore, this work summarizes the knowledge on this source and sheds light on a food source that is little known outside of the Amazon borders.

Host Plants and Fertilization Mediated Life History of American Serpentine Leaf Miner, Liriomyza trifolii (Burgess) (Diptera: Agromyzidae).

Herbivorous insects depend on the host plant to optimize their overall reproductive success, and balanced fertilization may alter the plant's quality against herbivory. Life history traits of the Liriomyza trifolii (Burgess) were determined under laboratory conditions using either unfertilized and fertilized plants of bean [Phaseolus vulgaris L. (Fabaceae)], chrysanthemum [Chrysanthemum × morifolium (Asteraceae)], potato [Solanum tuberosum (Solanaceae)], bell pepper [Capsicum annuum (Solanaceae)], and tomato [Solanum lycopersicum (Solanaceae)]. Results indicated that L. trifolii completed development on all studied unfertilized and fertilized plants. Nevertheless, a higher performance of the leaf miner was observed on bean and bell pepper plants compared to the other plants. Furthermore, there was an interaction of the host plant and fertilization with Calcium Aria or Sitam negatively affecting the fitness-related traits of the leaf miner. Application of these fertilizers resulted in delayed immature development of L. trifolii, decreased survival rate, and reduced adult longevity and fecundity. The activity of cinnamyl alcohol dehydrogenase (CAD), peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL) enzymes, as well as phenolic, flavonoid, and lignin content were higher in Calcium Aria + Sitam fertilized plants, intermediate in Calcium Aria and Sitam treated plants, and the lower in unfertilized plants. The development and survival of L. trifolii on different host plants, considering fertilization options, become important for deploying cultural control practices against this important pest species.

Analysis of Maillard reaction precursors and secondary metabolites in Chilean potatoes and neoformed contaminants during frying.

Southern Chile native potatoes are an interesting raw material to produce novel snacks like colored potato chips. These novel products should be comprehensively evaluated for the presence of undesirable compounds such as acrylamide, 5-hydroxymethylfurfural and furan, the main neoformed contaminants in starchy rich fried foods. This study evaluated the neoformed contaminant levels and oil content on chips made from eleven Chilean potato accessions and compared them with commercial samples. The neoformed contaminant contents were related to Maillard reaction precursor levels (reducing sugars and asparagine) and secondary metabolites (phenolic compounds and carotenoids). Neoformed contaminants correlated well among them and were weakly correlated with reducing sugars and asparagine. Acrylamide level in native potato chips ranged from 738.2 to 1998.6 µg kg-1 while from 592.6 to 2390.5 µg kg-1 in commercial samples. Thus, there is need to implement neoformed contaminant mitigation strategies at different steps of the production chain of colored potato chips.

Biofungicides Based on Plant Extracts: On the Road to Organic Farming.

Phytopathogenic fungi are responsible for diseases in commercially important crops and cause major supply problems in the global food chain. Plants were able to protect themselves from disease before humans played an active role in protecting plants. They are known to synthesize a variety of secondary metabolites (SMs), such as terpenes, alkaloids, and phenolic compounds, which can be extracted using conventional and unconventional techniques to formulate biofungicides; plant extracts have antifungal activity and various mechanisms of action against these organisms. In addition, they are considered non-phytotoxic and potentially effective in disease control. They are a sustainable and economically viable alternative for use in agriculture, which is why biofungicides are increasingly recognized as an attractive option to solve the problems caused by synthetic fungicides. Currently, organic farming continues to grow, highlighting the importance of developing environmentally friendly alternatives for crop production. This review provides a compilation of the literature on biosynthesis, mechanisms of action of secondary metabolites against phytopathogens, extraction techniques and formulation of biofungicides, biological activity of plant extracts on phytopathogenic fungi, regulation, advantages, disadvantages and an overview of the current use of biofungicides in agriculture.

An approach to combat multidrug-resistant K. pneumoniae strain using synergistic effects of Ocotea diospyrifolia essential oil in combination with amikacin.

The natural antimicrobial properties of essential oils (EOs) have contributed to the battle against multidrug-resistant microorganisms by providing new ways to develop more effective antibiotic agents. In this study, we investigated the chemical composition of Ocotea diospyrifolia essential oil (OdOE) and its antimicrobial properties combined with amikacin (AMK). Through gas chromatography-mass spectrometry (GCMS) analysis, the primary constituents of OdOE were identified as α-bisabolol (45.8 %), ß-bisabolene (9.4 %), γ-elemene (7.6 %), (Z)- ß-farnesene (5.2 %), spathulenol (3.5 %), (Z)-caryophyllene (3.3 %), and (E)-caryophyllene (3.1 %). In vitro assessments showed that the combined administration of OdOE and AMK exerted a synergistic antibacterial effect on the multidrug-resistant K. pneumoniae strain. This synergistic effect demonstrated bacteriostatic action. OdEO combined with amikacin showed protein extravasation within 2 h of treatment, leading to bacterial death, which was determined by a reduction in viable cell count. The effective concentrations showed hemocompatibility. In vivo assessments using Caenorhabditis elegans as a model showed the survival of 85 % of infected nematodes. Therefore, the combination OdEO combined with amikacin exhibited antimicrobial activity against a multidrug-resistant K. pneumoniae strain. Thus, OdOE is a promising agent that may be considered for development of antimicrobial treatment.

Antibacterial activity and biosynthetic potential of Streptomyces sp. PBR19, isolated from forest rhizosphere soil of Assam.

An Actinomycetia isolate, designated as PBR19, was derived from the rhizosphere soil of Pobitora Wildlife Sanctuary (PWS), Assam, India. The isolate, identified as Streptomyces sp., shares a sequence similarity of 93.96% with its nearest type strain, Streptomyces atrovirens. This finding indicates the potential classification of PBR19 as a new taxon within the Actinomycetota phylum. PBR19 displayed notable antibacterial action against some ESKAPE pathogens. The ethyl acetate extract of PBR19 (EtAc-PBR19) showed the lowest minimum inhibitory concentration (MIC) of ≥ 0.195 µg/mL against Acinetobacter baumannii ATCC BAA-1705. A lower MIC indicates higher potency against the tested pathogen. Scanning electron microscope (SEM) findings revealed significant changes in the cytoplasmic membrane structure of the pathogen. This suggests that the antibacterial activity may be linked to the disruption of the microbial membrane. The predominant chemical compound detected in the EtAc-PBR19 was identified as phenol, 3,5-bis(1,1-dimethylethyl), comprising 48.59% of the area percentage. Additionally, PBR19 was found to contain the type II polyketide synthases (PKS type II) gene associated with antibiotic synthesis. The predicted gene product of PKSII was identified as the macrolide antibiotic Megalomicin A. The taxonomic distinctiveness, potent antibacterial effects, and the presence of a gene associated with antibiotic synthesis suggest that PBR19 could be a valuable candidate for further exploration in drug development and synthetic biology. The study contributes to the broader understanding of microbial diversity and the potential for discovering bioactive compounds in less-explored environments.

Trichoderma and Mycosynthesis of Metal Nanoparticles: Role of Their Secondary Metabolites.

Nanocompounds are widely used in many fields such as environmental, medicine, or agriculture. Nowadays, these nanocompounds are mainly synthesized by chemical methods, causing environmental pollution and potential health problems. Thus, microorganisms have been investigated as potential nanoparticle green biosynthesizers. The main research is focused on the synthesis of nanoparticles (NPs) using algae, yeast, bacteria, and fungi. Among them, fungi have been the most used, due to their simple and effective mycosynthesis. Fungi as well as other organisms involved in green synthesis of NPs use their secondary metabolites (SMs) to mediate and catalyze the reactions to produce metal nanoparticles (MNPs) as well as being able to act as capping agents producing different physicochemical characteristics and biological activities in the MNPs. Among the various fungi used for mycosynthesis are Trichoderma species, which mediate the production of Ag, Cu, CuO, Zn, ZnO, and other MNPs. Here, we review the main SMs from Trichoderma that have been reported or suggested to contribute to synthesize or act as capping agents and their applications, as well as present the main challenges faced by this type of synthesis.

An Introduction to Plant Cell, Tissue, and Organ Culture: Current Status and Perspectives.

Plant cell, tissue, and organ cultures (PCTOC) have been used as experimental systems in basic research, allowing gene function demonstration through gene overexpression or repression and investigating the processes involved in embryogenesis and organogenesis or those related to the potential production of secondary metabolites, among others. On the other hand, PCTOC has also been applied at the commercial level for the vegetative multiplication (micropropagation) of diverse plant species, mainly ornamentals but also horticultural crops such as potato or fruit and tree species, and to produce high-quality disease-free plants. Moreover, PCTOC protocols are important auxiliary systems in crop breeding crops to generate pure lines (homozygous) to produce hybrids for the obtention of polyploid plants with higher yields or better performance. PCTOC has been utilized to preserve and conserve the germplasm of different crops or threatened species. Plant genetic improvement through genetic engineering and genome editing has been only possible thanks to the establishment of efficient in vitro plant regeneration protocols. Different companies currently focus on commercializing plant secondary metabolites with interesting biological activities using in vitro PCTOC. The impact of omics on PCTOC is discussed.

Diversity and potential functional role of phyllosphere-associated actinomycetota isolated from cupuassu (Theobroma grandiflorum) leaves: implications for ecosystem dynamics and plant defense strategies.

Exploring the intricate relationships between plants and their resident microorganisms is crucial not only for developing new methods to improve disease resistance and crop yields but also for understanding their co-evolutionary dynamics. Our research delves into the role of the phyllosphere-associated microbiome, especially Actinomycetota species, in enhancing pathogen resistance in Theobroma grandiflorum, or cupuassu, an agriculturally valuable Amazonian fruit tree vulnerable to witches' broom disease caused by Moniliophthora perniciosa. While breeding resistant cupuassu genotypes is a possible solution, the capacity of the Actinomycetota phylum to produce beneficial metabolites offers an alternative approach yet to be explored in this context. Utilizing advanced long-read sequencing and metagenomic analysis, we examined Actinomycetota from the phyllosphere of a disease-resistant cupuassu genotype, identifying 11 Metagenome-Assembled Genomes across eight genera. Our comparative genomic analysis uncovered 54 Biosynthetic Gene Clusters related to antitumor, antimicrobial, and plant growth-promoting activities, alongside cutinases and type VII secretion system-associated genes. These results indicate the potential of phyllosphere-associated Actinomycetota in cupuassu for inducing resistance or antagonism against pathogens. By integrating our genomic discoveries with the existing knowledge of cupuassu's defense mechanisms, we developed a model hypothesizing the synergistic or antagonistic interactions between plant and identified Actinomycetota during plant-pathogen interactions. This model offers a framework for understanding the intricate dynamics of microbial influence on plant health. In conclusion, this study underscores the significance of the phyllosphere microbiome, particularly Actinomycetota, in the broader context of harnessing microbial interactions for plant health. These findings offer valuable insights for enhancing agricultural productivity and sustainability.

Compounds from Natural Products Candidates to Drug for Chikungunya Virus Infection: A Systematic Review.

INTRODUCTION: Chikungunya fever is a disease caused by infection with the Chikungunya virus, transmitted by Aedes aegypti and Aedes albopictus mosquitoes. Despite its self-limited character, more than 60% of patients have chronic recurrent arthralgia with debilitating pain that lasts for years. AIM: The objective of this review was to gather and analyze evidence from the literature on potential therapeutic strategies with molecules from natural products for the treatment of Chikungunya fever. METHODS: A search was performed for clinical trials, observational studies, in vitro or in vivo, without restriction of the year of publication or language in electronic databases (Medline/PubMed, EMBASE, Google Scholar, The Cochrane Library, LILACS (BVS), clinical trial registries (Clinical Trials.gov), digital libraries from CAPES theses and dissertations (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brazil) and conference abstracts. A quality assessment of the selected studies was performed using the SYRCLE, RoB2 and SciRAP tools. RESULTS: 42 studies were included, which showed molecules with potential antiviral pharmacological activity or with activity in reducing the joint complications caused by CHIKV infection. CONCLUSIONS: Among the molecules found in the survey of references, regarding the class of secondary metabolites, flavonoids stood out and for this reason, the molecules may be promising candidates for future clinical trials. Overall, evidence from in vitro studies was of acceptable quality; in vivo and intervention studies showed a high risk of bias, which is a limitation of these studies.

Effect of the Proximity to the Quintero-Puchuncaví Industrial Zone on Compounds Isolated from Baccharis macraei Hook. & Arn: Their Antioxidant and Cytotoxic Activity.

Baccharis macraei Hook. & Arn (Asteraceae), commonly known as Vautro, is found in the coastal areas of central-southern Chile, including the industrial zone of Quintero-Puchuncaví, known for the contamination of its soils with heavy metals, which together with other factors generate abiotic stress in plant species, against which they present defensive mechanisms. For this reason, the objective was to evaluate the effect of abiotic stress generated by the proximity of B. macraei to the industrial complex by assessing the physiological and metabolic states reported by the extracts and compounds isolated from the species, as well as the photosynthetic capacity, metal content and production, and antioxidant activity and cytotoxicity against tumorigenic cell lines of the phytoconstituents. To this end, B. macraei was collected at two different distances from the industrial complex, observing that the closer the species is, the greater the concentration of copper in the soil, generating a decrease in the rate of electron transport in situ, but an increase in antioxidant activity with low cytotoxicity. This activity could be due to the presence of flavonoids such as Hispidulin, Cirsimaritina, and Isokaempferida, as well as monoterpenes, oxygenated and non-oxygenated sesquiterpenes identified in this study.

Genomic decoding of Theobroma grandiflorum (cupuassu) at chromosomal scale: evolutionary insights for horticultural innovation.

BACKGROUND: Theobroma grandiflorum (Malvaceae), known as cupuassu, is a tree indigenous to the Amazon basin, valued for its large fruits and seed pulp, contributing notably to the Amazonian bioeconomy. The seed pulp is utilized in desserts and beverages, and its seed butter is used in cosmetics. Here, we present the sequenced telomere-to-telomere genome of cupuassu, disclosing its genomic structure, evolutionary features, and phylogenetic relationships within the Malvaceae family. FINDINGS: The cupuassu genome spans 423 Mb, encodes 31,381 genes distributed in 10 chromosomes, and exhibits approximately 65% gene synteny with the Theobroma cacao genome, reflecting a conserved evolutionary history, albeit punctuated with unique genomic variations. The main changes are pronounced by bursts of long-terminal repeat retrotransposons at postspecies divergence, retrocopied and singleton genes, and gene families displaying distinctive patterns of expansion and contraction. Furthermore, positively selected genes are evident, particularly among retained and dispersed tandem and proximal duplicated genes associated with general fruit and seed traits and defense mechanisms, supporting the hypothesis of potential episodes of subfunctionalization and neofunctionalization following duplication, as well as impact from distinct domestication process. These genomic variations may underpin the differences observed in fruit and seed morphology, ripening, and disease resistance between cupuassu and the other Malvaceae species. CONCLUSIONS: The cupuassu genome offers a foundational resource for both breeding improvement and conservation biology, yielding insights into the evolution and diversity within the genus Theobroma.

Carbon-based nanomaterials as inducers of biocompounds in plants: Potential risks and perspectives.

Biocompounds are metabolites synthesized by plants, with clinically proven capacity in preventing and treating degenerative diseases in humans. Carbon-based nanomaterials (CNMs) are atomic structures that assume different hybridization and shape. Due to the reactive property, CNMs can induce the synthesis of metabolites, such as biocompounds in cells and various plant species, by generating reactive oxygen species (ROS). In response, plants positively or negatively regulate the expression of various families of genes and enzymes involved in physiological and metabolomic pathways of plants, such as carbon and nitrogen metabolism, which are directly involved in plant development and growth. Likewise, ROS can modulate the expression of enzymes and genes related to the adaptation of plants to stress, such as the glutathione ascorbate cycle, the shikimic acid, and phenylpropanoid pathways, from which the largest amount of biocompounds in plants are derived. This document exposes the ability of three CNMs (fullerene, graphene, and carbon nanotubes) to positively or negatively regulate the activity of enzymes and genes involved in various plant species' primary and secondary metabolism. The mechanism of action of CNMs on the production of biocompounds and the effect of the translocation of CNMs on the growth and content of primary metabolites in plants are described. Adverse effects of CNMs on plants, prospects, and possible risks involved are also discussed. The use of CNMs as inducers of biocompounds in plants could have implications and relevance for human health, crop quality, and plant adaptation and resistance to biotic and abiotic stress.