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Main conclusion During their domestication process, the species of the genus Opuntia lose their ability to survive in the wild. Presence and concentration of secondary metabolites which play a role in the interaction with their surroundings are modified but without an identifiable pattern. A domestication gradient based on morphological characteristics has been previously described for the species in the Opuntia genus. Secondary metabolites are a diverse group of bioactive compounds that relate to a species evolution, both in their natural and artificial (domestication process) selection environments. In addition, these compounds are associated with plant resistance to stress when growing in the wild. A comprehensive characterization of secondary metabolite profiles in the Opuntia genus that accounts for the genotypic differences related to the degree of domestication has not previously been conducted. This study evaluated the phytochemical composition of young cladodes from fifteen variants, of O. ficus-indica , O. albicarpa Sheinvar, and O. megacantha Salm-Dyck, identified as species with a highly advanced, advanced and intermediate degree of domestication, respectively, and O. hyptiacantha A. Web, and O. streptacantha Lem. identified as wild-intermediate and wild species. Analyses were carried out using a HPLC-diode array detection technique. Out of the 13 identified and quantified phenolic molecules and terpenoids, only the caffeic, ferulic and syringic acids, and the terpenoid β- amyrin were present in all variants. The flavonoid luteolin was absent in all five species. Gallic, vallinic, p -hydroxybenzoic, chlorogenic and p -coumaric acids were only present in 53–87% of variants; flavonoids quercetin, isorhamnetin, rutin and apigenin in 47–87% of the variants. Both, oleanolic acid and peniocerol, were present only in 60% of variants. Isorhamnetin was absent in O. hyptiacantha and quercetin in O. streptacntha . Differences and similarities in the secondary metabolites content showed no recognizable trend relating to the degree of domestication across the species in this genus.

The hybrid Sechium edule H387 07, commonly known as chayote, has shown potential as an antiproliferative, cytotoxic, and pro-apoptotic agent in the murine leukemia cell lines P388 (macrophagic) and J774 (monocytic) and in the myelomonocytic leukemia cell line WEHI-3. However, despite these reported bioactivities, its pharmacokinetic profile remains largely unexplored. Understanding the absorption, distribution, and elimination of this hybrid is critical for addressing unmet therapeutic needs and for advancing the development of natural product-based therapies. These effects are attributed to the presence of phenols, flavonoids, and cucurbitacins in its organic extracts. In this study, the pharmacokinetic parameters of secondary metabolites from methanolic extracts of Sechium H387 07 were evaluated after oral administration in mice, while its segregant H387 M16 was subjected to complementary phytochemical characterization. Methanolic extracts of Sechium edule H387 07 were orally administered to mice at doses of 8, 125, and 250 mg/kg, and plasma, liver, and urine samples were collected at 1, 6, 24, and 48 h post-treatment. High-performance liquid chromatography (HPLC) identified polyphenols and cucurbitacins, notably cucurbitacin B (CuB) and cucurbitacin IIA (CuIIA), in the biological samples, and pharmacokinetic variables such as the maximum plasma concentration (Cmax), time to reach maximum concentration (Tmax), half-life (T1/2), and volume of distribution (Vd) were determined. For instance, CuB exhibited a Cmax of 37.56 µg/mL at 1 h post-dose after oral administration of 125 mg/kg, confirming its rapid absorption and systemic distribution. Notably, the presence of CuIIA in plasma was documented for the first time, along with the pharmacokinetic profiles of apigenin, phloretin, CuB, CuE, and CuI. In parallel, the segregant H387 M16 was characterized via colorimetric assays, thin-layer chromatography (TLC), HPLC, and antioxidant activity tests, which revealed high levels of flavonoids, phenols, and cucurbitacins, with an antioxidant activity of approximately 75% at the highest tested dose (1 mg/mL), supporting its suitability for future bioassays. Overall, these findings not only provide novel pharmacokinetic data for key metabolites of the H387 07 hybrid but also establish the phytochemical and antioxidant profile of its segregant H387 M16. This dual characterization strengthens the evidence of the therapeutic potential of Sechium genotypes and provides a valuable foundation for future studies aiming to develop standardized protocols and explore translational applications in drug development and natural product-based therapies.

The xylem of Cactaceae is a complex system with different types of cells whose main function is to conduct and store water, mostly during the development of primary xylem, which has vessel elements and wide-band tracheids. The anatomy of primary xylem of Cactaceae has been widely studied, but little is known about its chemical composition. The aim of this study was to determine the structural chemical composition of the primary xylem of Cactaceae and to compare it with the anatomy in the group. Seeds from eight cacti species were used, representing the Pereskioideae, Opuntioideae, and Cactoideae subfamilies. Seeds were germinated and grown for 8 months. Subsequently, only the stem of the seedling was selected, dried, milled, and processed following the TAPPI T-222 om-02 norm; lignin was quantified using the Klason method and cellulose with the Kurshner-Höffer method. Using Fourier transform infrared spectroscopy, the percentage of syringyl and guaiacyl in lignin was calculated. Seedlings of each species were fixed, sectioned, and stained for their anatomical description and fluorescence microscopy analysis for the topochemistry of the primary xylem. The results showed that there were significant differences between species ( < 0.05), except in the hemicelluloses. Through a principal component analysis, it was found that the amount of extractive-free stem and hot water-soluble extractives were the variables that separated the species, followed by cellulose and hemicelluloses since the seedlings developed mainly parenchyma cells and the conductive tissue showed vessel elements and wide-band tracheids, both with annular and helical thickenings in secondary walls. The type of lignin with the highest percentage was guaiacyl-type, which is accumulated mainly in the vessels, providing rigidity. Whereas in the wide-band tracheids from metaxylem, syringyl lignin accumulated in the secondary walls S2 and S3, which permits an efficient flow of water and gives the plant the ability to endure difficult conditions during seedling development. Only one species can be considered to have paedomorphosis since the conductive elements had a similar chemistry in primary and secondary xylem.

Background Tepary bean ( Phaseolus acutifolius A. Gray) is one of the five species domesticated from the genus Phaseolus with genetic resistance to biotic and abiotic stress. To understand the mechanisms underlying drought responses in seed storage proteins germinated on water and polyethylene glycol (PEG-6000) at -0.49 MPa, we used a proteomics approach to identify potential molecular target proteins associated with the low water potential stress response. Methods Storage proteins from cotyledons of Tepary bean seeds germinated at 24, 48 and 72 h on water and PEG-6000 at -0.49 MPa were analyzed by one-dimensional electrophoresis (DE) with 2-DE analysis and shotgun mass spectrometry. Using computational database searching and bioinformatics analyses, we performed Gene Ontology (GO) and protein interactome (functional protein association network) String analyses. Results Comparative analysis showed that the effect of PEG-6000 on root growth was parallel to that on germination. Based on the SDS‒PAGE protein banding patterns and 2-DE analysis, ten differentially abundant seed storage proteins showed changes in storage proteins, principally in the phaseolin and lectin fractions. We found many proteins that are recognized as drought stress-responsive proteins, and several of them are predicted to be intrinsically related to abiotic stress. The shotgun analysis searched against UniProt’s legume database, and Gene Ontology (GO) analysis indicated that most of the seed proteins were cytosolic, with catalytic activity and associated with carbohydrate metabolism. The protein‒protein interaction networks from functional enrichment analysis showed that phytohemagglutinin interacts with proteins associated with the degradation of storage proteins in the cotyledons of common bean during germination. Conclusion These findings suggest that Tepary bean seed proteins provide valuable information with the potential to be used in genetic improvement and are part of the drought stress response, making our approach a potentially useful strategy for discovering novel drought-responsive proteins in other plant models.

Agave salmiana Otto ex Salm-Dyck, a crassulacean acid metabolism plant that is adapted to water-limited environments, has great potential for bioenergy production. However, drought stress decreases the requirement for light energy, and if the amount of incident light exceeds energy consumption, the photosynthetic apparatus can be injured, thereby limiting plant growth. The objective of this study was to evaluate the effects of drought and re-watering on the photosynthetic efficiency of A. salmiana seedlings. The leaf relative water content and leaf water potential decreased to 39.6 % and −1.1 MPa, respectively, over 115 days of water withholding and recovered after re-watering. Drought caused a direct effect on photosystem II (PSII) photochemistry in light-acclimated leaves, as indicated by a decrease in the photosynthetic electron transport rate. Additionally, down-regulation of photochemical activity occurred mainly through the inactivation of PSII reaction centres and an increased thermal dissipation capacity of the leaves. Prompt fluorescence kinetics also showed a larger pool of terminal electron acceptors in photosystem I (PSI) as well as an increase in some JIP-test parameters compared to controls, reflecting an enhanced efficiency and specific fluxes for electron transport from the plastoquinone pool to the PSI terminal acceptors. All the above parameters showed similar levels after re-watering. These results suggest that the thermal dissipation of excess energy and the increased energy conservation from photons absorbed by PSII to the reduction of PSI end acceptors may be an important acclimation mechanism to protect the photosynthetic apparatus from over-excitation in Agave plants.

The chayote fruit is a nontraditional vegetable belonging to the Cucurbitaceae family. The fruit has an endocarpic recalcitrant seed that emerges postharvest, drastically shortening its shelf life. In this study, the changes during fruit and seed development before and after harvest (ah) are reported. Additionally, in order to investigate how growth regulators (GRs) affect seed germination, 2-cloroethylphosphonic acid (CPA) (200 µL L−1), gibberellic acid (GA3) (100 and 200 mg L−1), auxin (2,4-D) (0.5 and 1.0 mM), and abscisic acid (ABA) (0.5 and 1.0 mM) were applied after harvest. The results showed that the chayote fruit reached horticultural maturity at 21 days after anthesis, with a sigmoid trend: phase I featured slow growth and high transpiration; in phase II, growth was accelerated and accumulation of endosperm was observed; and in phase III, both growth rate and transpiration were reduced, soluble sugars increased, and the seed showed 25% cotyledon development. At day 13 ah, CPA, GA3, and 2,4-D (0.5 mM) increased seed germination, with values between 10 and 15 mm of the embryonary axis, and the treatments with 2,4-D (1 mM) and ABA (0.5 and 1.0 mM) retarded their growth (2–6 mm). This research allowed us to reveal the phenological phases and the shelf life of the chayote fruit, as well as the results of possible postharvest treatment with GRs; our results suggest that strategies to delay viviparism and prolong the shelf life of the fruit should be applied before 10 days ah, when the embryonic axis of the seed has not developed.

The lulo plant (Solanum quitoense Lamarck) is native to South America. In Mexico, this species shows potential for the conversion of agroecosystems. It is used as food and pharmaceutical sources for metabolites. However, there are few papers related to how this species can grow under conditions outside of the Andean countries (Bolivia, Colombia, Ecuador, and Peru). The objective of this research was to evaluate the development of lulo under cloud forest conditions and the effect of inoculating the plant with mycorrhizae (Funneliformis mosseae (T. H. Nicolson and Gerd.) C. Walker and A. Schüssler, and Entrophospora colombiana Spain and N. C. Schenck) and diammonium phosphate (DAP: NPK 18-46-00) fertilization. The plant growth, leaf area, mycorrhizal colonization, and leaf mineral content were evaluated from transplant to fruit formation. The experiment was conducted under field conditions in volcanic soils (clayey Vertisol) in a cloud forest. The inoculation of E. colombiana was 86.19% of the colonization, and the content of N, K, Ca, Mg, Mn, Cu, Zn, and Fe in the leaves was the higher in these plants. The highest P content was obtained from the DAP treatment and the height of the plant was 11.8% and 12.5% in the treatments using DAP and E. colombiana, respectively. The plant growth was significantly higher in the plants inoculated with E. colombiana followed by DAP. The plants inoculated with F. mosseae registered lower values than the control. Lulo plants grow in the climate and soils of volcanic origin of the cloud forest. The results showed that AMF colonization was beneficial and outperformed the native strains. The results are new for the introduced lulo plants in Mexico and can help reduce the learning path for commercial cultivation.

Chilli CM334 (Capsicum annuum L.) is resistant to Phytophthora capsici Leonian (Pc), but Nacobbus aberrans Thorne and Allen, 1944 (Na) broke down its resistance in plants previously infected by the nematode. Peroxidase (POD) and L-phenylalanine ammonia-lyase (PAL) activity, total soluble phenols (TSP) and chlorogenic acid concentration in CM334 plants inoculated with either or both pathogens (Na-Pc) were compared; also, the toxic effect of some phenolic acids on Na was tested in vitro. The highest POD activity (5.3 μM tetraguaiacol mg⁻¹ protein min⁻¹) was registered in plants inoculated only with Pc, while those inoculated only with Na showed the lowest (3.3 μM) (P ≤ 0.05). PAL activity was 39.9 nM trans-cinnamic acid μg⁻¹ protein min⁻¹ in plants inoculated only with Pc, and it was lower (19.3 nM) and similar in non-inoculated plants or those with Na and with Na-Pc (P ≤ 0.05). Usually, plants inoculated with Pc alone had higher contents of TSP (P ≤ 0.05) (1.9 mg tannic acid g⁻¹ dry matter) and plants inoculated with Na or Na-Pc had lower levels (0.8 and 0.9 mg) than those non-inoculated (1.3 mg). CM334 plants inoculated with Na showed a significant reduction (10-37% and 12-17%, in roots and leaves) in the concentration of chlorogenic acid as compared to the non-inoculated. Vanillic, trans-cinnamic, p-coumaric and syringic acids had greater nematicidal effects (P ≤ 0.05) than chlorogenic acid in vitro. Apparently Na modified the defence responses in CM334 plants as POD and PAL activities and TSP and chlorogenic acid concentrations were reduced.

A gradient of domestication based on morphological characteristics has been observed in species of Opuntia genus; but, a biophysical and physiological gradient have been not described. This study aimed to quantify biophysical and physiological characteristics in nopalitos (edible young cladodes of flat-stemmed spiny cacti) of 15 variants of five Opuntia species in a domestication gradient, including wild (O. streptacantha Lem.), semi-wild (O. hyptiacantha F.A.C. Weber), semi-domesticated (O. megacantha Salm-Dyck), more domesticated (O. albicarpa Scheinvar), and that recognized with the highest degree of domestication [O. ficus-indica (L.) Miller]. We hypothesized that biophysical and physiological characteristics of nopalitos are modified throughout the domestication process and that such changes will be evident when variants with different degree of domestication are grown under drought conditions. Tissue firmness, water potential (ψW), osmotic potential (ψπ), content of total soluble solids (TSS), content of malic acid, and membranes permeability were evaluated in nopalitos harvested from plants after 60 days without watering. A randomized design, with six replications and a plant as experimental unit by treatment, was used. The data were analysed by ANOVA, multiple comparisons of means by Tukey test (P ≤ 0.05) among variants and species, and multivariate analysis of principal components. Firmness (from 4.6 ± 0.082 to 6.8 ± 0.053 kgf/cm²), TSS (from 4.86 ± 0.105 to 6.33 ± 0.142 °Brix), membrane permeability (from 26 ± 0.712 to 31 ± 0.474 (µS cm⁻¹)/g⁻¹) and malic acid content (from 0.61 ± 0.008 to 0.82 ± 0.014 g 100 g⁻¹ wet matter) increased during domestication, and simultaneously ψW and ψS decreased (from −0.85 ± 0.034 to −1.1 ± 0.030 MPa and −1.01 ± 0.011 to −1.15 ± 0.011 MPa). The firmness, SST and ψS are the main characteristics that contributed to separate the Opuntia species on the gradient of domestication. Opuntia species on a domestication gradient based on morphometric characteristics of plants (cladodes, nopalitos and cactus pear fruits) correlate to biophysical and physiological characteristics of nopalitos.

Domestication is an evolutionary process that culminates with the origin of individuals or populations that are morpho-physiologically, chemically and genetically different from their wild, congeneric relatives. The aim of the present study was to quantify the inter- and intra-specific variation in fruit biomass, number of seeds, and physical characteristics of seeds in O. streptacantha Lem., O. hyptiacantha F.A.C. Weber, O. megacantha Salm-Dyck, O. albicarpa Scheinvar and O. ficus - indica (L.) Mill., the least, intermediate, and most highly domesticated species. The hypothesis was that selecting larger fruits with fewer and softer seeds (normal and aborted) during domestication reduced the interspecific variation in fruit biomass, number of seeds, and physical characteristics of seeds in Opuntia spp., Cactaceae. For fruits of 89 variants of the Southern Mexican Plateau, total biomass and biomass of pulp with seeds was quantified; seed length, width, thickness and dehydrated mass were measured, as well as hardness of normal seeds. The total number of seeds was quantified and normal and aborted seeds were counted separately. A randomized design, with 89 treatments (variants) and six replicates and a fruit as experimental unit per treatment was used. The data were analysed by ANOVA, Tukey’s multiple comparison test ( p  ≤ 0.05), multivariate ordination (principal components analysis) and classification (clustering analysis). Inter-specific analysis indicated that fruits of the most highly domesticated variants ( O. albicarpa and O. ficus - indica ) had higher biomass ( p  ≤ 0.05), followed by those of O. hyptiacantha and O. megacantha and wild variants of O. streptacantha , and non-significant differences existed in seed thickness or hardness. Fruit and pulp biomass were positively and significantly correlated with seed biomass. Species with greater domestication clustered according to their larger fruits (≥117.83 g) and the greater number of aborted seeds (≥65). Domestication of Opuntia has also modified seed dimensions and increased the number of aborted seeds per fruit (≤11 to ≥65).