Chemical Fingerprint of 'Oblainska' Sour Cherry (Prunus cerasus L.) Pollen

The aim of this research was to analyze sugars and phenolics of pollen obtained from 15 different 'Oblainska' sour cherry clones and to assess the chemical fingerprint of this cultivar. Carbohydrate analysis was done using high-performance anion-exchange chromatography (HPAEC) with pulsed amperometric detection (PAD), while polyphenols were analyzed by ultra-high-performance liquid chromatography-diode array detector-tandem mass spectrometry (UHPLC-DAD MS/MS) system. Glucose was the most abundant sugar, followed by fructose and sucrose. Some samples had high level of stress sugars, especially trehalose. Rutin was predominantly polyphenol in a quantity up to 181.12 mg/kg (clone III/9), with chlorogenic acid (up to 59.93 mg/kg in clone III/9) and p-coumaric acid (up to 53.99 mg/kg in clone VIII/1) coming after. According to the principal component analysis (PCA), fructose, maltose, maltotriose, sorbitol, and trehalose were the most important sugars in separating pollen samples. PCA showed splitting off clones VIII/1, IV/8, III/9, and V/P according to the quantity of phenolics and dissimilar profiles. Large differences in chemical composition of studied 'Oblainska sour cherry' clone pollen were shown, proving that it is not a cultivar, but population. Finally, due to the highest level of phenolics, clones IV/8, XV/3, and VIII/1 could be singled out as a promising one for producing functional food and/or in medicinal treatments

Variation of the chemical and biochemical responses to salinity during germination and early growth of seedlings of two populations of Agave durangensis Gentry

Agave durangensis (Asparagaceae) sustains a mescal industry in Mexico. The main reproductive strategy of the species is by seeds. The increased demand for agave-based beverages encourages producers to seek new cultivation areas. However, more than half of the territory of the country includes arid and semiarid zones, which are highly affected by salinity. The aim of the current study was to determine if salinity triggers different seed germination potential and variable biochemical and chemical responses in seedlings of two populations of A. durangensis, that might confer different tolerance to salinity. Seeds from each population were irrigated with four salinity treatments. Germination potential, as well as growth parameters and biochemical and chemical attributes of seedlings, were determined. Although with reduced germinability and germination speed, seeds of the two populations were able to germinate even under the strongest NaCl concentration (100 mM) evaluated. Effects in the growth parameters were registered; however, the seedlings of both populations survived throughout the experiments, increasing chlorophyll content and cell viability in most saline treatments. The enzymatic defense mechanism and the accumulation of proline were activated in a salt-dependent manner, which did not occur with the phenolic compounds; however, monomeric anthocyanin accumulation was outstanding under the two strongest NaCl concentrations evaluated. Important interpopulation differences were registered in each type of response, which were differently regulated under variable NaCl concentrations, some of them being more important than others under a particular saline condition. Seeds from the population Durango were more sensitive to salinity

Polyphenolic composition of Lantana camara and Lippia chevalieri, and their Antioxidant and Antimicrobial Activities

In the present study, the antioxidant and antibacterial activities of methanolic extracts of two Verbenaceae (Lantana camara L. and Lippia chevalieri Moldenke: aerial part) were investigated. Their polyphenolic composition in the ethyl acetate and aqueous fractions were characterized by HPLC-DAD. The antioxidant capability of the methanolic extracts was assessed by the Ferric Reducing Antioxidant Power (FRAP) and the scavenging activity of the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). The Minimum Inhibitory Concentrations (MIC) of the methanolic extracts (25 µg mL-1), and the minimum bactericidal concentrations (MBC) (12.5 µg mL-1) against 13 pathogenic bacteria and four serotyped bacteria from the American Type Culture Collection (ATCC) were also determined by the agar-well diffusion method. The results indicated that the L. chevalieri extracts are rich in phenolic compounds (among the 27 polyphenolic compounds detected, 20 belong to L. chevalieri) and showed the highest antioxidant activities, simultaneously on iron (III) to iron (II)-reducing activity and the radical scavenging activity. However, L. camara displayed the best and the broadest antimicrobial spectrum, especially on Shigella flexneri and Pantoea sp. (two Gram-negative strains of bacteria). The nature of polyphenolics compounds detected (phenol acid and flavone) in the L. camara can justify this activity.Key words: Verbenaceae, HPLC-DAD, antioxidant activity, antimicrobial activity, polyphenolic compound

Effect of microencapsulated phenolic compound extracts of Maclura tinctoria (L.) Steud on growth performance and humoral immunity markers of white leg shrimp (Litopenaeus vannamei, Boone, 1931) juveniles

Aim of study: The effect of microencapsulated phenolic compound extracts of Maclura tinctoria (MTBE) on growth performance and humoral immunity markers of the white leg shrimp Litopenaeus vannamei juveniles (0.5 ± 0.2 g initial weight) was studied.Area of study: M. tinctoria was collected from Hampolol, Campeche, and Arroyo del Agua, Culiacan, Sinaloa, Mexico.Material and methods: Three MTBE inclusions (0.5, 1, and 2.5 g MTBE/kg, Purina®) were compared with a control commercial feed (Purina®) during 30 days. Nine phenolic acids, nine flavonols, four dihydro-flavonoids, four flavones, and seven unidentified phenolic compounds were determined fin the MTBE using a Perkin Elmer® HPLC chromatograph and diode array-detection.Main results: The mean concentrations of total phenolic compounds, total flavonoid compounds, and condensed tannins were 198.05 ± 5.59 mg gallic acid equivalent (GAE) g-1 dw, 78.57 ± 1.80 quercetin equivalent g-1, and 28.32 ± 0.33 mg epicatechin equivalent g-1, respectively. The ferric reducing antioxidant power and the total antioxidant capacity, respectively, averaged 28.32 mg GAE mL-1 and 10.9 mg ascorbic acid equivalent mL-1. Survival, weight gain, and specific growth rate of L. vannamei were similar among the experimental diets. The dietary inclusion of MTBE at 0.5 g/kg of food showed significant higher (p < 0.05) plasma hemocyte lysate protein (1.35 ± 0.055 µg mL-1), prophenoloxidase (0.47 ± 0.15, Abs. 492 nm), and superoxide anion (O2.-) activity (0.21 ± 0.07, Abs. 630 nm).Research highlights: The supplementation of MTBE at 0.5 g/kg of food could be considered as a potential alternative additive for L. vannamei diet in the juvenile production, since it improved the response of the humoral immunity markers at post larval life stages, when cultivated shrimp are more susceptible to be infected by pathogens

Variation of the phenolic composition and a-glucosidase inhibition potential of seeds, soaked seeds, and sprouts of four wild forms and four varieties of common bean (Phaseolus vulgaris)

The determination of the changes in the composition of bioactive phenolic compounds of germinating seeds which accumulate high levels of these compounds could contribute to the understanding of the germination mechanism and the development of markers for the selection of plant genotypes. In the current study, the changes in the phenolic composition and a-glucosidase inhibition activity, taking place during the germination of four wild forms and four varieties of common bean (Phaseolus vulgaris L.) from Durango Mexico, were determined. A total of 66 phenolic compounds (19 phenolic acids, 18 isoflavones, 18 flavonol glycosides, 3 flavonol aglycones, 3 flavones, 2 dihydroflavonoids, 2 chalcones and one non-identified type) were found by HPLC-DAD, which were differentially accumulated by the seeds, 24 h-soaked seeds, and 4 day-sprouts of each genotype. The accumulation of the flavonol aglycones, myricetin, quercetin and kaempferol was distinctive of the wild seeds. Soaking not only caused leaching and degradation but also triggered the synthesis of new phenolic compounds whereas germination diversified the composition of isoflavones and flavonol glycosides. The seeds of all genotypes analyzed were important inhibitors of a-glucosidase, improving their potential after soaking and germination. The results suggested that the structure rather than the concentration of the flavonoids and phenolic acids determined the inhibitory potential of a-glucosidase of samples. The principal component analysis and cluster analysis revealed HPLC-DAD phenolic profiles as genotype-specific chemomarkers at any of the states (seeds, soaked seeds, and sprouts). The results have wide implications on agronomy and food quality

α-Glucosidase and α- amylase inhibition potentials of ten wild Mexican species of Verbenaceae

Purpose: To evaluate the inhibitory activity of 10 wild Verbenaceae species from Mexico against α- glucosidase and α-amylase.Methods: Ethanol leaf extracts of 10 Verbenaceae species from Mexico were prepared. The inhibitory activity of the extracts against α-glucosidase and α-amylase was evaluated using enzymatic protocols. At least four serial diluted concentrations of each extract was used to calculate the half-maximal inhibitory concentration (IC50).Results: The 10 evaluated Verbenaceae species showed high α-glucosidase inhibition activity, but a low inhibitory effect on α-amylase. Aloysia gratissima (IC50 = 0.122 mg/mL), Verbena carolina (IC50 = 0.112 mg/mL), Bouchea prismatica (IC50 = 0.122 mg/mL), Verbena menthiflora (IC50 = 0.071mg/mL) and Priva mexicana (IC50 = 0.032 mg/mL) exhibited the strongest inhibitory activities against α- glucosidase.Conclusion: All the Verbenaceae species studied possess α-glucosidase inhibitory effect, with P. mexicana being the one with the strongest activity. These findings demonstrate the highs potential of these species as a source of natural antihyperglycemic agents for type 2 diabetes therapy.Keywords: Hyperglycemic, Diabetes, α-Glucosidase, α-Amylase Verbenaceae, Aloysia gratissima, Bouchea prismatica, Priva mexican

Effect of salinity on DNA methylation and antioxidant phenolic compounds of wild watercress (Rorippa nasturtium aquaticum)

Epigenetic changes are involved in plant responses to stress. Cytosine methylation is one of the most important epigenetic changes, regulating gene expression. In this paper, the MSAP (methylation-sensitive amplification polymorphism) method was used to find out how the watercress (Rorippa nasturtium aquaticum) genome changed in response to 0, 60, 80, and 100 mM NaCl and how that affected phenylalanine ammonium lyase (PAL) activity, phenolic content, and antioxidant capacity. The results showed an inverse correlation between methylation levels and PAL activity and the contents of total phenolics and flavonoids, indicating salt stress-induced reprogramming of the methylation pattern of watercress, which has a negative effect on the synthesis of phenolics. The results revealed a significant decrease in phenolic contents and antioxidant activity under low and moderate salinity compared to control and an increase under strong salinity compared to moderate salinity. The findings of this study contribute to our understanding of the reprogramming of DNA methylation under salinity and its effect on watercress phenolic metabolism

Los fenoles del polen del género Zea

The variability of the pollen phenol composition of 32 populations of Zea mays subsp. mexicana, Zea mays subsp. parviglumis, Zea mays subsp. mays, Zea diploperennis, Zea perennis, and Zea luxurians from Mexico and Guatemala were analyzed. The phenol profiles were assessed by HPLC-DAD, and UPLC-TOF-MS. A total of 23 phenolics (four phenolic acids, 16 flavonols, and three dihydroflavonoids) were found. Quercetin glycosides (seven derivatives besides the quercetin aglycone itself) were the predominant compounds in the pollen of all analyzed species and subspecies. The major compound in all the samples, including the pollen of maize, was identified as quercetin-3,3’-O-diglucoside. The pollen of all the species and subspecies of Zea examined showed very similar patterns of accumulated phenols; however, variation in the minor compounds (phenolic acids and dihydroflavonoids) allowed to discern some inter- and intraspecific variations, although the split of Zea in the sectionsLuxuriantes and Zea was not clearly supported. The low level of variability of the pollen phenol profiles throughout the genus Zea supports the proposal that maize and some teosintes are conspecific groups, and indicates that the pollen phenol composition is highly conserved in the different taxa of Zea.Se analizó la variabilidad de la composición fenólica del polen de 32 poblaciones de Zea mays subsp. mexicana, Zea mays subsp. parviglumis, Zea mays subsp. mays, Zea diploperennis, Zea perennis yZea luxurians de México y Guatemala. Los perfiles se obtuvieron por cromatografía líquida de alta presión con detector de arreglo de diodos (HPLC-DAD) y cromatografía líquida de ultra resolución acoplada a espectrómetro de masas de tiempo de vuelo (UPLC-TOF-MS). Se encontró un total de 23 compuestos fenólicos (cuatro ácidos fenólicos, 16 flavonoles y tres dihidroflavonoides). Los derivados glicósidos de quercetina (siete derivados, además de la quercetina aglicona misma) fueron las substancias predominantes en todos los analisis realizados. El compuesto principal, el más abundante y presente en la totalidad de las muestras, incluido el maíz, se identificó como quercetina-3,3’-O-diglucósido. El polen de todas las especies y subespecies de Zea analizadas mostraron patrones muy similares de fenoles acumulados; sin embargo, diferencias en los compuestos menores (ácidos fenólicos y dihidroflavonoides) permitieron discernir variaciones inter e intraespecíficas, aunque la división del género en las dos secciones Luxuriantes y Zea no fue claramente sustentada. La baja variación de los perfiles fenólicos del polen dentro del género Zea apoya la propuesta de que el maíz y algunos teocintles son grupos conespecíficos, e indica que la composición fenólica del polen fue altamente conservada en los diferentes taxa de Zea a lo largo del tiempo