Control sustentable poscosecha: extractos de Larrea cuneifolia mediados por nades frente a Botrytis cinerea

Botrytis cinerea es un hongo ubicuo que ocasiona la podredumbre gris, una de las principales enfermedades de fruta en poscosecha, siendo responsable de pérdidas económicas. Debido a la creciente preocupación por los efectos adversos del uso de pesticidas, la búsqueda de alternativas se presenta como una meta prioritaria. En este contexto, los extractos de plantas representan una rica fuente de biocompuestos con atractivas propiedades antimicrobianas. Recientemente, los solventes eutécticos naturales (NADES) se han propuesto como agentes extractantes sustentables de compuestos bioactivos a partir de plantas. En el presente estudio, se evaluó un bioextracto de L. cuneifolia basado en NADES hacia B. cinerea. Para este propósito, se usó un NADES compuesto por ácido láctico, glucosa y agua (LGH) como agente de extracción y se comparó con solventes tradicionales en términos de capacidad antioxidante y contenido fenólico total. Además, la actividad antimicrobiana del bioextracto se evaluó in vitro e in vivo en uvas inoculadas artificialmente. A una concentración del 2% el bioextracto fue capaz de inhibir el crecimiento miceliar de B. cinerea en un 92%. Interesantemente, L. cuneifolia mostró un excelente rendimiento para el control de la podredumbre gris en uvas, demostrando su potencial como alternativa sustentable a los fungicidas sintéticos.Botrytis cinerea is a ubiquitous fungus causing gray mold, the main postharvest disease in fruit, which implies important economic losses in agriculture. With growing concern over health and environmental effects of pesticides, the search for eco-friendly alternatives is a clear priority. Plant extracts represent a rich source of biocompounds with attractive antimicrobial properties. In the last decade, Natural Deep Eutectic Solvents (NADES) has emerged as an auspicious green extraction media to achieve bioextract for a sustainable postharvest control. In the present study, a novel L. cuneifolia NADES-based bioextract was evaluated against B. cinerea. To this purpose, a NADES composed by lactic acid, glucose and water (LGH) was used as extracting agent and compared with traditional solvents in terms of antioxidant capacity and total phenolic content. Furthermore, the bioextract antifungal activity was tested in vitro and also in vivo on artificially inoculated grapes, in order to obtain preliminary data about the efficacy on gray mold development. The antimicrobial activity of the bioextract was assessed using agar diffusion method against B. cinerea, inhibition of 92% was achieved with the bioextract at 2%. Notably, L. cuneifolia bioextract showed an excellent performance for gray mold control on grapes, supporting their potential as alter-native green fungicide.Fil: Boiteux, Joana Jaqueline. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Espino, Magdalena Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Fernández, María de Los Ángeles. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Pizzuolo, Pablo Humberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Silva, María Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentin

Effects of pulsed electric fields (PEF) on vitamin C and its antioxidant properties

In this study, pulsed electric fields (PEF) treatments and their effects on the structure of vitamin C (VIT-C) were estimated by fluorescence and Fourier transform infrared (FT-IR) spectroscopy, the relative content of VIT-C was measured by HPLC and the antioxidant properties of treated VIT-C by DPPH radical scavenging as well as reducing power tests. The fluorescence intensity of treated VIT-C increased slightly compared to the untreated VIT-C. Moreover, the effect of PEF on the structure of VIT-C was observed using the FT-IR spectra. These phenomena indicated that the PEF affected the conformation of VIT-C, which promoted the VIT-C isomer transformed enol-form into keto-form. In addition, the PEF treatments did not suffer the damage to VIT-C and could slow down the oxidation process in involving of experimental conditions by HPLC. The antioxidant properties of the treated VIT-C were enhanced, which was proved by radical scavenging and also the reducing power tests

Antioxidant Capacity Of Frangipani (Plumeria Alba) Powder Extract

This research aimed to identify the antioxidant capacity, vitamin C (ascorbic acid), and total phenolic compounds of frangipani flower powder. The powder was extracted using ethanol, methanol, acetic acid, and water (aquadest). Antioxidant capacity of each extract were determined using 2,2-diphenyl-1-picrylhydrazyl radical scavenging method, vitamin C were determined using 2,4 Dinitrophenylhydrazine, and total phenolic compounds were determined using Folin Ciocalteu reagent. All of parameters were measured by spectrofotometer. The result shows that the highest value of antioxidant capacity was ethanolic extract (18.19%) and the lowest value was acetic acid extract (12.74%). The highest value of vitamin C was aqueous extract (3.49 mg/100g) and the lowest value was acetic acid extract (3.02 mg/100g). The highest value of total phenolic content was aqueous extract (25.49 mg GAE/g) and the lowest value was acetic acid extract (22.74 mg GAE/g). In conclusion, the higher antioxidant capacity was not always followed by the higher of vitamin C and total phenolic compounds

QSAR studies on di(hetero)arylamines derivatives of benzo[b]thiophenes as free radical scavengers

Synthetic antioxidants are widely used in food industry y, but because of toxic and carcinogenic effects revealed by some compounds such as BHA and BHT, their use is being restricted. The pursuit for novel compounds with antioxidant properties gained higher significance, since these compounds may contribute for the prevention of diseases in which free radicals are implicated

Fully-Unintegrated Parton Distribution and Fragmentation Functions at Perturbative k_T

We define and study the properties of generalized beam functions (BFs) and fragmenting jet functions (FJFs), which are fully-unintegrated parton distribution functions (PDFs) and fragmentation functions (FFs) for perturbative k_T. We calculate at one loop the coefficients for matching them onto standard PDFs and FFs, correcting previous results for the BFs in the literature. Technical subtleties when measuring transverse momentum in dimensional regularization are clarified, and this enables us to renormalize in momentum space. Generalized BFs describe the distribution in the full four-momentum k_mu of a colliding parton taken out of an initial-state hadron, and therefore characterize the collinear initial-state radiation. We illustrate their importance through a factorization theorem for pp -> l^+ l^- + 0 jets, where the transverse momentum of the lepton pair is measured. Generalized FJFs are relevant for the analysis of semi-inclusive processes where the full momentum of a hadron, fragmenting from a jet with constrained invariant mass, is measured. Their significance is shown for the example of e^+ e^- -> dijet+h, where the perpendicular momentum of the fragmenting hadron with respect to the thrust axis is measured.Comment: Journal versio

Gingival Recession, Oral Hygiene and Associated Factors Among Tanzanian Women.

Females are generally more motivated with regard to oral hygiene practices and thus brush their teeth more frequently than males. To determine the prevalence of gingival recession, oral hygiene status, oral hygiene practices and associated factors in women attending a maternity ward in Tanzania. Cross-sectional descriptive study. Maternity ward of Muhimbili National Hospital, Tanzania. Four hundred and forty six women were interviewed on oral hygiene practices and maternal factors, and a full-mouth examination was done to determine the presence of plaque, calculus, gingival bleeding and gingival recession at six sites per tooth. The prevalence of gingival recession (GR) > or =1 mm was 33.6%, calculus 99.3%, plaque 100%, and gingival bleeding 100%. Oral hygiene practices included toothbrushing (98.9%), brushing frequency > or =2 times/day (61.2%), horizontal brushing method (98%), and using a plastic toothbrush (97.8%). Factors that were significantly associated with gingival recession were age (OR = 2.0, 95% CI = 1.3-3.2), presence of calculus (OR(a) = 3.8, 95% CI=2.5-7.1), and gingival bleeding on probing (OR = 4.2, 95% CI = 2.5-7.1). Tooth cleaning practices and maternal factors, especially the number of pregnancies or deliveries were not significantly associated with gingival recession. In this study population, oral hygiene was poor and gingival recession was associated with age, calculus and gingival inflammation rather than with tooth cleaning practices

Thermoelectric and Seebeck coefficients of granular metals

In this work we present a detailed study and derivation of the thermopower and thermoelectric coefficient of nano-granular metals at large tunneling conductance between the grains, g_T>> 1. An important criterion for the performance of a thermoelectric device is the thermodynamic figure of merit which is derived using the kinetic coefficients of granular metals. All results are valid at intermediate temperatures, E_c>>T/g_T>\delta, where \delta is the mean energy level spacing for a single grain and E_c its charging energy. We show that the electron-electron interaction leads to an increase of the thermopower with decreasing grain size and discuss our results in the light of future generation thermoelectric materials for low temperature applications. The behavior of the figure of merit depending on system parameters like grain size, tunneling conductance, and temperature is presented.Comment: 27 pages, 10 figures, revtex

Agreement between mothers and children with malocclusion in rating children's oral health-related quality of life

Introduction: The aim of this study was to compare the assessment of oral health-related quality of life (OH-QoL) between children with malocclusion and their mothers, by using responses to the child perceptions questionnaire and the parental-caregivers perceptions questionnaire. Methods: The study was conducted in 90 children, aged 11 to 14 years, with a malocclusion grade of 4 or 5 according to the index of orthodontic treatement need dental health component. The children and their mothers completed the questionnaires independently. Results: The mean ratings were similar for total scores (children, 20.4; mothers, 20.1), oral symptoms (children, 5.2; mothers, 4.7), and social well-being (children, 4.3; mothers, 4.8). However, the mothers group had a lower mean score for functional limitations (children, 5.3; mothers, 3.6) and a higher mean score for emotional well-being (children, 5.6; mothers, 7.1). The correlations between children's and mothers' responses ranged from rs = 0.545 for total score and emotional well-being to rs = 0.357 for functional limitations. There were good correlations between their responses to global (rs = 0.466) and life overall (rs = 0.427) questions, but poor correlations between the 2 questions, suggesting that these concepts were considered differently. Conclusions: Maternal opinions were similar to those of their children for the overall impact on OH-QoL of malocclusion, but mothers were more dissatisfied with the appearance of their children's teeth and overestimated the emotional impact of malocclusion. It would be useful to develop a specific measure to assess OH-QoL in children with malocclusion. (Am J Orthod Dentofacial Orthop 2010;137:631-8

A study of the antioxidant capacity of oak wood used in wine ageing and the correlation with polyphenol composition

The antioxidant capacity of oak wood used in the ageing of wine was studied by four different methods: measurement of scavenging capacity against a given radical (ABTS, DPPH), oxygen radical absorbance capacity (ORAC) and the ferric reducing antioxidant power (FRAP). Although, the four methods tested gave comparable results for the antioxidant capacity measured in oak wood extracts, the ORAC method gave results with some differences from the other methods. Non-toasted oak wood samples displayed more antioxidant power than toasted ones due to differences in the polyphenol compositon. A correlation analysis revealed that ellagitannins were the compounds mainly responsible for the antioxidant capacity of oak wood. Some phenolic acids, mainly gallic acid, also showed a significant correlation with antioxidant capacity