Characterization of the complete chloroplast genome sequence of Agave durangensis (Asparagales: Asparagaceae: Agavoideae).

Agave durangensis commonly known as agave cenizo, is an endemic Agave species in Mexico used for mescal production, yet its taxonomic delimitation is still controversial. This study aimed to enhance taxonomic clarity by characterizing its chloroplast genome. Chloroplast DNA was isolated from 2-year-old A. durangensis leaves. The complete chloroplast genome size was 156,441 bp, comprising a large single-copy region (LSC), a pair of inverted repeat regions (IR), and a small single-copy region (SSC). Annotation revealed 87 protein-coding genes, 38 tRNAs, and 8 rRNAs, with notable gene inversions. Phylogenetic analysis suggests, A. durangensis forms a separate lineage within the Agave genus.

Synthesis of Chitosan Microparticles Encapsulating Bacterial Cell-Free Supernatants and Indole Acetic Acid, and Their Effects on Germination and Seedling Growth in Tomato (Solanum lycopersicum).

Encapsulation of biostimulant metabolites has gained popularity as it increases their shelf life and improves their absorption, being considered a good alternative for the manufacture of products that stimulate plant growth and fruit production. Cell-free supernatants (CFS) were obtained from nine indole-3-acetic acid (IAA) producing bacterial strains. Stenotrophomonas maltophilia (PT53T) produced the highest concentration of IAA (15.88 µg/mL) after 48 h of incubation. CFS from this strain, as well as an IAA standard were separately encapsulated in chitosan microparticles (CS-MP) using the ionic gelation method. The CS-MP were analyzed by Fourier transform infrared spectroscopy (FTIR), showing absorption bands at 1641, 1547, and 1218 cm-1, associated with the vibrations of the carbonyl C=O, the N-H amine, and the bond between chitosan (CHI) and sodium tripolyphosphate (TPP). The effects of unencapsulated CFS, encapsulated CFS (EN-CFS), and encapsulated IAA standard (EN-IAA) on germination and growth of seven-day-old tomato (Solanum lycopersicum) seedlings were studied. Results showed that both EN-CFS and EN-IAA significantly (p < 0.05) increased seed germination rates by 77.5 and 80.8%, respectively. Both CFS and EN-IAA produced the greatest increase in aerial part length and fresh weight with respect to the treatment-free test. Therefore, it was concluded that the application of EN-CFS or EN-IAA could be a good option to improve the germination and growth of tomato seedlings.

Comparison of the phenolic contents and epigenetic and genetic variability of wild and cultivated watercress (Rorippa nasturtium var. aquaticum L.)

Background: Epigenetic modifications are key factors modulating the expression of genes involved in the synthesis of phytochemicals. The knowledge of plant epigenetic and genetic variations can contribute to enhance the production of bioactive compounds. These issues have been little explored thus far in Rorippa nasturtium var. aquaticum L. (watercress), an edible and medicinal plant. The aim of the current study was to determine and compare the phenolic composition and epigenetic and genetic variations between wild and cultivated watercress. Results: Significant differences were found in the quantitative phenolic composition between wild and cultivated watercress. The eight primer combinations used in the methylation-sensitive amplification polymorphism (MSAP) method revealed different epigenetic status for each watercress type, the cultivated one being the most epigenetically variable. The genetic variability revealed by the EcoRI/MspI amplification profile and also by eight inter-simple sequence repeat (ISSR) primers was different between the two types of watercress. The results of the Mantel test showed that the correlation between genetic and epigenetic variations has diminished in the cultivated type. Cluster analyses showed that the epigenetic and genetic characterizations clearly discriminated between wild and cultivated watercress. Conclusions: Relevant chemical, epigenetic, and genetic differences have emerged between wild and cultivated watercress. These differences can contribute to fingerprint and develop quality control tools for the integral and safety use and the commercialization of watercress. The richness of epialleles could support the development of tools to manipulate the watercress epigenome to develop high bioproduct­producing cultivars

Phenolic constituents and antioxidant properties of five wild species of Physalis (Solanaceae).

BACKGROUND: Fruits of wild species of the genus Physalis are consumed as food and calyces and leaves are used in traditional medicine. The phenolic composition of the species of this genus have been scarcely studied. To contribute to a better knowledge for the use of all the potential of these wild species of plants, leaves, fruits, and calyces of five wild species of the genus were analyzed for their phenolic composition and antioxidant properties. RESULTS: Important tissue- and species-dependent variations were found. Calyces of Physalis subulata showed the highest contents of phenolics (176.58 mg of gallic acid equivalents/g dry tissue), flavonoids (39.63 mg/g dry tissue), and phenolic acids (50.57 mg of quercitrin equivalents/g dry tissue), and its leaves displayed the highest total antioxidant capacity (3.59 mg of ascorbic acid equivalents/mL) and one of the highest reduction powers (0.54 µg of ascorbic acid equivalents/mL). A high performance liquid chromatography with photodiode array detection analysis revealed a total of 28 phenolic compounds in foliar tissues (mainly kaempferol-3-O-glycosides), 16 in fruits (mainly phenolic acids), and 16 in calyces (mainly kaempferol-3-O-glycosides); the profiles of these compounds in the three types of tissue were species-specific. CONCLUSIONS: The studied species of Physalis are important sources of phenolics with relevant antioxidant activity. The current results indicate that phenolic profiles are valuable specific chemical markers and can be relevant as food tracing and authenticity indicators for plant-based preparations involving species of Physalis.

Evaluation of foliar phenols of 25 Mexican varieties of common bean (Phaseolus vulgaris L.) as antioxidants and varietal markers.

The antioxidant properties and the foliar phenol composition of 25 Mexican varieties of Phaseolus vulgaris L. (common bean) were evaluated. Phaseolus coccineus was analysed with comparative aims. The high performance liquid chromatography with photodiode array detection analysis revealed 27 phenolics in the leaves of P. vulgaris (13 quercetin-3-O-glycosides, 8 kaempferol-3-O-glycosides, 2 myricetin glycosides and 4 phenolic acids) and 5 in P. coccineus (2 kaempferol-3-O-glycoside, 2 apigenin-7-O-glycoside and 1 luteolin-7-O-glycoside). All extracts showed high levels of phenols and flavonoids (0.964-5.601 mg g⁻¹ dry tissue, and 0.287-1.418 mg g⁻¹ dry tissue, respectively) and relevant antioxidant properties, suggesting that the leaves of the varieties of P. vulgaris are a significant source of natural antioxidants. The foliar phenol profiles were species-specific and, besides, the qualitative variation allowed discriminating among varieties of P. vulgaris. These profiles can represent an important varietal authenticity proof.

Variability of antioxidant activity among honeybee-collected pollen of different botanical origin

Se determinaron las actividades antioxidantes de los extractos crudos de una mezcla de polen apícola y de cada uno de los seis polen constituyentes que formaban esa mezcla. Las determinaciones se hicieron por el método de sustancias reactivas al ácido tiobarbitúrico (TBARS) en preparaciones microsomales de hígado y por el método del bloqueo del radical libre 2,2-difenil-1-picrilhidracilo (DPPH*). Las actividades se compararon con la composición de flavonoles y ácidos fenólicos y con los contenidos de flavonoles en el polen. Todos los extractos mostraron actividades antioxidantes. Éstas fueron diferentes para cada especie y no estuvieron claramente asociadas al contenido de flavonoles en el polen. El polen de Amarathus hybridus mostró una alta capacidad inhibidora de la oxidación lipídica. El de la mezcla entera y el de Tagetes sp. fueron efectivos bloqueadores de radicales libres.

The antioxidant activities of total extracts of a mixture of honeybee-collected pollen and its six constituent pollens were determined by lipid peroxidation assay by the thiobarbituric acid reactive substances (TBARS) test on hepatic microsomal preparations and by free radical scavenging (2,2-diphenyl-1-picrylhydrazyl; DPPH*) method. Activities were compared to the flavonol and phenolic acid compositions and flavonol contents in pollen. All extracts showed antioxidant activities as radical scavenger substances and as inhibitors of lipid peroxidation. Antioxidant activities were different for each species and were not clearly associated to the flavonol content in pollen. Pollen of Amaranthus hybridus was a potent lipid oxidation inhibitor, and that of Tagetes sp. and the whole mixture were effective antiradical substances.

Determinaram-se as atividades antioxidantes dos extratos crus de uma mescla de pólen apícola e de cada um dos seis polens constituintes que formavam essa mescla. As determinações se fizeram pelo método de substâncias reativas ao ácido tiobarbitúrico (TBARS) em preparações microssomais de fígado e pelo método do bloqueio do radical livre 2,2-difenil-1-picrilhidracilo (DPPH*). As atividades se compararam com a composição de flavonóis e ácidos fenólicos e com os conteúdos de flavonóis no pólen. Todos os extratos mostraram atividades antioxidantes. Estas foram diferentes para cada espécie e não estiveram claramente associadas ao conteúdo de flavonóis no pólen. O pólen de Amarathus hybridus mostrou uma alta capacidade inibidora da oxidação lipídica. O da mescla inteira e o de Tagetes sp. foram efetivos bloqueadores de radicais livres.

Efectos letal y subletal de lactonas sobre la garrapata del ganado Boophilus annulatus Say / Lethal and sublethal effects of lactones on the cattle tick Boophilus annulatus Say

En este trabajo se evaluó el efecto letal y subletal de cinco lactonas obtenidas de un cultivo líquido de Streptomyces sp, sobre la garrapata del ganado (Boophilus annulatus Say) y la cantidad y calidad de su ovoposición. Los resultados se compararon con los producidos por un fármaco comercial a base de ivermectina. La lactona 3 povocó 30 por ciento de mortalidad, el más alto de las lactonas en experimentación y un descenso mayor en la eclosión de la puesta que el causado por el fármaco comercial usado, lo que le confiere un uso potencial como insecticida