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Plants (Basel) ; 11(11)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35684186


At least 59 maize races (Zea mays L.) have been registered in Mexico. The feeding damage caused by insects and mites to maize crops generates up to ~30% of maize yield losses. Spider-mite-resistant plants are needed. The red spider mite, Tetranychus merganser Boudreaux (Acari: Tetranychidae), is distributed in the United States, China, Mexico, and Thailand. It is considered a potential pest in Mexican agriculture. The aim of this study was to evaluate the resistance mechanisms (antixenosis and antibiosis) of 11 native maize populations, representative of each race of maize grown in Tamaulipas, Mexico, to T. merganser under laboratory conditions. The aim was also to obtain information on the chemical composition and some morphological characteristics of these maize races and to identify resistant maize races for incorporation into a breeding program. Antixenosis was assessed by non-preference for oviposition and feeding. Antibiosis was measured by growth rate (ri). The presence of secondary metabolites in the 11 maize races were different. In the 11 maize races, quantitative analysis of total phenol concentration, total flavonoid concentration, and antioxidant capacity were significantly different. The multivariate analysis of variance showed that there is evidence of antixenosis noted by maize race differences in egg laying and percentage feeding damage but not of antibiosis noted by growth rate. Red spider mites laid significantly more eggs on the Celaya (24 h: 25.67 ± 17.04, 48 h: 42.67 ± 26.86, 72 h: 49.33 ± 28.54) race than on Raton (24 h: 7.00 ± 5.00, 48 h: 12.67 ± 8.02, 72 h: 14.67 ± 9.29) and Elotes Occidentales × Tuxpeño (24 h: 9.67 ± 5.85, 48 h: 15.33 ± 10.69, 72 h: 17.67 ± 10.97) races. However, the growth rate and mortality of T. merganser in the 11 corn races were similar. The Vandeño (24 h: 11.67 ± 2.89, 48 h: 27.67 ± 7.64, 72 h: 30.00 ± 18.03) and Tabloncillo × Tuxpeño (24 h: 18.33 ± 7.64, 48 h: 25.00 ± 8.66, 72 h: 25.00 ± 8.66) races were the most resistant to red spider mite damage, whereas the most susceptible race was Celaya (24 h: 26.67 ± 15.28, 48 h: 48.33 ± 29.30, 72 h: 65.00 ± 30.00). Further analysis by PCA at 24, 48, and 72 h found the Celaya race positively correlated to growth rate and oviposition of T. merganser and to a lesser extent with the percentage of feeding damage, suggesting that the Celaya race was most susceptible to T. merganser. At 24 h, the Vandeño race was most resistant, given a negative correlation to growth rate and oviposition by T. merganser. The PCA at 48 and 72 h noted the Elotes Occidentales × Tuxpeño race was most resistant to red spider mite, with negative relationships to growth rate and oviposition and, to a lesser extent, to feeding damage. This resistance is due to the differences in both its morphological characteristics and the secondary metabolites present in their leaves.

CienciaUAT ; 15(2): 156-168, ene.-jun. 2021. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1285899


Resumen Capsicum annuum var. glabriusculum presenta adaptaciones locales a distintas dinámicas antropocéntricas y ecológicas, por lo que ampliar sus usos alimenticios a partir de su potencial antioxidante permitirá contribuir al conocimiento para fortalecer cadenas de valor, robustecer su aprovechamiento y el consumo de plantas comestibles silvestres locales. El objetivo de este trabajo fue suplementar con chile piquín un aceite comestible comercial de cártamo y evaluar su capacidad antioxidante, a través de la determinación del contenido de compuestos fenólicos y mediante ensayos de captación de radicales libres ABTS+ y DPPH·, evaluados en: 1) la muestra de chile piquín a través de dos solventes de extracción y 2) en el aceite suplementado y sin suplementar a los 0 d, 7 d, 14 d, 21 d y 28 d posteriores a la preparación (DPP). El chile piquín presentó altos valores antioxidantes, el análisis de varianza (ANOVA) indicó que el extracto acuoso superó al hidroalcohólico. El ANOVA factorial mostró diferencias significativas en los tres parámetros antioxidantes evaluados. Estas disimilitudes se asociaron a la suplementación, tiempo (DPP) y la combinación de la suplementación y DPP. La suplementación del aceite de cártamo con C. annuum var. glabriusculum enriqueció 66 % su valor antioxidante. La comparación de medias mostró diferencias significativas en la combinación de tratamientos y DPP. La combinación de aceite suplementado y los DPP presentó variabilidad en los datos de polifenoles totales y habilidad contra ABTS+. Se observó una relación inversa entre los DPP y compuestos fenólicos totales y capacidad contra ABTS+, contrario a la prueba para DPPH·. Los resultados obtenidos validan que la adición de chile piquín incrementa la biofuncionalidad del aceite de cártamo y puede ser alternativa de fuente de antioxidantes naturales.

Abstract Capsicum annuum var. glabriusculum presents local adaptations to different anthropocentric and ecological dynamics. Therefore, expanding its food uses based on its antioxidant potential will contribute to knowledge about ways to strengthen value chains, enhance their use and encourage the consumption of local wild edible plants. The aim of this work was to evaluate the antioxidant capacity of commercial edible safflower oil supplemented with piquín chili by determining the content of phenolic compounds and by assays of free radical scavenging in ABTS+ and DPPH·. The evaluation included: 1) the piquín chili sample through two extraction solvents and 2) the supplemented and unsupplemented oil at 0 d,7 d, 14 d, 21 d and 28 d after preparation (DPP). The piquín chili presented high antioxidant values. The analysis of variance (ANOVA) indicated that the aqueous extract surpassed the hydroalcoholic extract. The factorial ANOVA showed significant differences in the three antioxidant parameters evaluated. These dissimilarities were associated with supplementation, time (DPP) and the combination of supplementation and DPP. Safflower oil supplementation with C. annuum var. glabriusculum enriched 66 % more its antioxidant value. The comparison of means showed significant differences in the combination of treatments and DPP. The combination of supplemented oil and DPP showed variability in total polyphenol data and ability against ABTS +. An inverse relationship was observed between DPP and total phenolic compounds, and capacity against ABTS +, contrary to the test for DPPH·. The results obtained validate the argument that the addition of piquín chili increases the biofunctionality of safflower oil and can be an alternative source of natural antioxidants.

J Insect Sci ; 19(5)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606745


The Central American locust, Schistocerca piceifrons piceifrons (Walker) is a major agricultural pest in Mexico and Central America. Control measures against this pest have generated much environmental damage and substantial financial costs because chemical insecticides are used. Yet various Orthoptera species also appear to be a potential source of nutrients and a source of bioactive metabolites. Here, we studied the presence of secondary metabolites in the adult stage of S. p. piceifrons by applying different colorimetric techniques. Adults were collected from the southern region of Tamaulipas, Mexico, during September-December 2017. These samples were subjected to sequential processes of eviscerating, drying, pulverizing, extracting, and detecting of metabolites. Extractions were carried out in water, 50% ethanol, and absolute ethanol. The presence of phenolic compounds, alkaloids, tannins, saponins, flavonoids, and quantity of antioxidants against the DPPH (2, 2-diphenyl-1-picrylhydrazyl) and ABTS (2, 2'-azino-bis, 3-ethylbenzothiazoline-6-sulfonic acid) radicals were determined and reported. Proximate analysis showed that S. p. piceifrons has a high protein content (80.26%), low fat content (6.21%), and fiber content (12.56%) similar to other Orthoptera species. Chitin and chitosan contents of S. p. piceifrons were 11.88 and 9.11%, respectively; the recovery percentage of chitosan from chitin was 76.71%. Among the Orthoptera, the protein content of this pest is among the highest while its contents of chitin and chitosan are similar to those of other insect species (e.g., Bombix mori Linnaeus [Lepidoptera: Bombycidae]). Our results suggest this pest species is a potential source of bioactive compounds of biotechnological interest for use by pharmaceutical and food industries.

Gafanhotos/química , Animais , Antioxidantes/análise , Quitina/análise , Quitosana/análise , Proteínas de Insetos/análise , México , Peptídeo Hidrolases/análise , Fenóis/análise
Chem Biodivers ; 16(10): e1900381, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31403756


The variability in the phytochemical concentrations of Capsicum annuum var. glabriusculum has not been extensively analyzed among wild populations and ecologic niches in its phylogeographic area. This study aimed to determine the variations in the phytochemical and antioxidant contents of the wild Piquin chili. The total flavonoid content of hydroalcoholic extracts (0.06 to 0.70 mg equivalent of quercetin per gram of dry weight (mg QE/g DW)), free radical-scavenging capacity for 2,2-diphenyl-1-picrylhydrazyl (DPPH. ) radicals (0.55 to 8.55 mm TE/g DW), amount of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+ ) in aqueous extracts (18.13 to 107.6 mm TE/g DW) and pungency (21,760 to 88,476 Scoville heat units) were highly variable. By analyzing the spatial distribution using the first three principal components, correlations between the phytochemical content and the free radical-scavenging capacity (in both extracts) and flavonoid and phenolic contents (in the hydroalcoholic extract) were observed. Consistent with the statistical analysis, the spatial analysis showed intraregional differences in composition patterns, with an emphasis on central and coastal areas. Flavonoid contents, polyphenol contents and free radical-scavenging activity were the phytochemical components that mainly contributed to the diversity of the population.

Compostos de Bifenilo/antagonistas & inibidores , Capsicum/química , Sequestradores de Radicais Livres/farmacologia , Compostos Fitoquímicos/farmacologia , Picratos/antagonistas & inibidores , Ácidos Sulfônicos/antagonistas & inibidores , Tiazóis/antagonistas & inibidores , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação
Molecules ; 24(13)2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31269738


Rhus pachyrrhachis and Rhus virens are medicinal plant species with important uses in northeastern Mexico. They belong to a complex of Rhus species called "lantriscos", which are used for medicinal applications. The medicinal effects of these species are based on traditional use, however, they require phytochemical research to validate their medicinal properties, as well as structural characterization for their correct identification during the collecting practice and uses. The phytochemical potential of aqueous extracts from R. pachyrrhachis and R. virens was analyzed by the quantification of total phenolic content (TPC), free radical-scavenging potential, and total flavonoids, with a comparison of four drying methods, and some phenolic compounds were identified. Furthermore, the stems and leaves of both species were anatomically characterized to establish a differentiation. R. pachyrrhachis and R. virens showed similar values of phytochemical contents, although the TPC content (0.17 mg of gallic acid equivalent per gram of dry weight, GAE/g DW) was higher in R. virens. The drying method used affected the metabolite contents, and this behavior was related to the species. Regarding the phenolic compounds, shikimic acid, galloylquinic acid, and gallic acid were identified in both species, however, quinic acid was only found in Rhus pachyrrhachis, while vanillic acid O-hexoside was identified only in Rhus virens. At the anatomical level, the pubescence associated with trichomes on the leaves of Rhus pachyrrhachis was highlighted as the main differential characteristic.

Dessecação , Sequestradores de Radicais Livres/química , Medicina Tradicional , Fenóis/química , Rhus/química , Flavonoides/análise , Rhus/citologia
Molecules ; 23(10)2018 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-30332792


The total phenolic compounds content, free radical-scavenging capacity and capsaicinoid content in populations of wild Piquin chili (C. annuum) were studied. Aqueous and hydroalcoholic extracts from nine ecotypes were evaluated. High contents of phenolic compounds and free radical-scavenging capacities were observed for both extracts; however, the values that were found for the hydroalcoholic phase were substantially higher. LC-MS analysis allowed for the detection of 32 compounds, where apigenin-8-C-glucoside followed by vanillic acid 1-O-ß-o-glucopyranosylester (Isomer I or II) and 7-ethoxy-4-methylcoumarin were the most widely distributed; they were found in more than 89% of the ecotypes. The diversity of identified phenolic compounds was different among ecotypes, allowing them to be distinguished by chemical diversity, free radical-scavenging capacities and heat Scoville units. The total capsaicinoid content was higher in Population I (23.5 mg/g DW) than in Populations II and III, which had contents of 15.3 and 10.7 mg/g DW, respectively. This variability could lead to phytochemical exploitation and the conservation of the natural populations of wild chili.

Capsicum/química , Sequestradores de Radicais Livres/isolamento & purificação , Fenóis/isolamento & purificação , Capsaicina , Cromatografia Líquida , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Espectrometria de Massas , Estrutura Molecular , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia
J Food Sci Technol ; 54(13): 4268-4276, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29184233


Moringa oleifera (Moringaceae) is a specie of significant importance because of its multiple nutraceutical properties, that has led to increase in its consumption. The seeds contain a high percentage of protein (37.48%). However, little is known about the bioactive properties of these proteins and peptides, especially those generated by enzymatic hydrolysis. The objective of this study was to evaluate the biofunctional properties of total hydrolysates (TH) and peptide fractions from protein isolates of moringa seeds. Isoelectric protein isolates were prepared and TH were obtained by digestion with trypsin, chymotrypsin and pepsin-trypsin for 2.5 and 5 h. TH were fractioned by ultrafiltration (UF) with a 10 kDa membrane to generate the peptide fractions. In all treatments, the antioxidant capacity was significantly higher in peptide fractions > 10 kDa with 5 h of hydrolysis. The results showed that the fraction > 10 kDa of pepsin-trypsin digested for 5 h presented a better Angiotensin Converting Enzyme inhibition (ACE-I) activity with an IC50 of 0.224 µg/µl. Also, antidiabetic activity was enhanced in pepsin-trypsin treatment with 5 h of hydrolysis showing an IC50 of 0.123 µg/µl. Finally, this study showed that hydrolysates of moringa seed proteins had excellent in vitro nutraceutical potential.

Asian Pac J Trop Med ; 10(2): 121-125, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28237475


OBJECTIVE: To evaluate differences in yield and composition of the essential oil and antioxidant contents in Turnera diffusa plants from localities in central region of Tamaulipas. METHODS: Samples were collected in Tamaulipas, Mexico in the arid zone. Essential oil was obtained through steam distillation and analyzed using GC-MS. Polyphenol contents, antioxidant activities using ABTS and ferric reducing antioxidant power (FRAP) methods also were evaluated. RESULTS: A total of 21 compounds were identified in the essential oils; nevertheless, only Eucalyptol, 1,4-Methanocycloocta[d]pyridazine, 1,4,4a,5,6,9,10,10a-octahydro-11,11-dimethyl-, (1à,4à,4aà,10aà) y Ethanone, 1-(1,3-dimethyl-3-cyclohexen-1-yl) were detected in the three sites. Highest contents were registered in the sample from Padrón y Juárez with phenolic content of 33.85 mg GAE/g of dry material and antioxidant activities with ABTS 72.32% and with FRAP 21.33 mg GAE/g of dry material. Statistical differences were observed in essential oil, phenolics and antioxidants contents between populations. CONCLUSIONS: Results suggest that climatic differences and origin influence the phytochemicals in the medicinal plant Turnera diffusa, and thus, it is worth to consider such effects for industrial and medicinal purposes.

Electron. j. biotechnol ; 18(3): 161-168, May 2015. ilus, tab
Artigo em Inglês | LILACS | ID: lil-750642


Background The high capacity of chloroplast genome response to integrate and express transgenes at high levels makes this technology a good option to produce proteins of interest. This report presents the stable expression of Pectin lyase (PelA gene) and the first stable expression of manganese peroxidase (MnP-2 gene) from the chloroplast genome. Results pES4 and pES5 vectors were derived from pPV111A plasmid and contain the PelA and MnP-2 synthetic genes, respectively. Both genes are flanked by a synthetic rrn16S promoter and the 3'UTR from rbcL gene. Efficient gene integration into both inverted repeats of the intergenic region between rrn16S and 3'rps'12 was confirmed by Southern blot. Stable processing and expression of the RNA were confirmed by Northern blot analysis. Enzymatic activity was evaluated to detect expression and functionality of both enzymes. In general, mature plants showed more activity than young transplastomic plants. Compared to wild type plants, transplastomic events expressing pectin lyase exhibited enzymatic activity above 58.5% of total soluble protein at neutral pH and 60°C. In contrast, MnP-2 showed high activity at pH 6 with optimum temperature at 65°C. Neither transplastomic plant exhibited an abnormal phenotype. Conclusion This study demonstrated that hydrolytic genes PelA and MnP-2 could be integrated and expressed correctly from the chloroplast genome of tobacco plants. A whole plant, having ~ 470 g of biomass could feasibly yield 66,676.25 units of pectin or 21,715.46 units of manganese peroxidase. Also, this study provides new information about methods and strategies for the expression of enzymes with industrial value.

Poligalacturonase/genética , Poligalacturonase/metabolismo , Tabaco , Cloroplastos/genética , Peroxidase/genética , Peroxidase/metabolismo , Temperatura , Bactérias/enzimologia , Transformação Genética , Parede Celular , Southern Blotting , Reação em Cadeia da Polimerase , Fungos/enzimologia , Concentração de Íons de Hidrogênio , Hidrolases