Folin-Ciocalteu Reaction Alternatives for Higher Polyphenol Quantitation in Colombian Passion Fruits.

Passiflora edulis Flavicarpa, Passiflora edulis Sims, and Passiflora ligularis Juss are Colombian fruits (passion fruits) of important exportation value. They act efficiently as antioxidants, antifungal, and antimicrobial compounds due to their high polyphenol content. Polyphenols can be quantified by the Folin-Ciocalteu (F-C) reaction. Food matrices, solvent polarity, and several different reacting conditions are critical for the optimum extraction and quantification of polyphenols. Chromatographic identification and quantitation are satisfactory with access to a vast number of reference standards considering the availability of abundant phenolic compounds in crude extracts. The purpose of this study was to evaluate alternatives and specific F-C reacting conditions aiming at determining the highest total phenolic content (TPC) in three Colombian Passifloras. Among optimum reacting conditions, reduced reaction time and diluted alkali conditions yielded desirable positive results highlighting lower working time and minimum reagent waste production. For higher extraction yield, acetone 70% was the best solvent to capture more phenolics from the seedless pulp of these Colombian passion fruits.

Multi-residue analysis of pesticides in blood plasma using hollow fiber solvent bar microextraction and gas chromatography with a flame ionization detector.

The challenges faced on pesticide extraction from biological samples are finding a method that allows a multi-residue extraction, pre-concentration, clean-up, and isolation of analytes in just one step. In this sense, the hollow fiber - liquid phase microextraction method (HF- LPME) in the "solvent bar" mode was used to optimize and validate a method for pesticide multi-residue analysis in blood plasma at trace levels, through gas chromatography coupled with a flame ionization detector (GC-FID). Hollow fiber solvent bar microextraction HF-SBME was carried out with octanol immobilized into the pores of hydrophobic polypropylene fiber and disposed within a matrix of blood plasma, spiked with a mixture of pesticides (monocrotophos, lindane, aldrin, methyl parathion, endosulfan, dieldrin, DDD, DDT, and endrin). The optimization parameters evaluated were: extraction temperature and time, stirring speed, and salt concentration. A principal component analysis was performed to visualize the analytes' behaviour based on their explained variance, and then, a Box-Behnken analysis was generated to identify the optimum parameters. According to the PCA, all pesticides showed similar responses to the extraction method and the response of dieldrin exhibit the lowest variance. Moreover, the stationary points selected from the Box-Behnken analysis were 25.5 °C for the extraction temperature, 870 rpm for stirring speed, 16 min for extraction time, and 8.3 % w/v of salt concentration. Moreover, the validation results proved that HF-SBME is an alternative technique for pesticide multi-residue extraction in blood plasma. The analytes were able to concentrate, reaching 46 fold enrichment. The solvent type, sample and solvent volume were narrowed down without changing the method's precision or accuracy. The relative standard deviation was under 10 %, and the recovery was between 55 % and 105 % for the different analytes excepting lindane, which had lower recovery (27 %). The detection limits were 0.02 until 0.13 µg mL-1 for most of the pesticides used. Finally, HF-SBME is a good alternative for pesticide multi-residue extraction in complex matrices like plasma.

Physicochemical treatments for the reduction of aflatoxins and Aspergillus niger in corn grains (Zea mays).

BACKGROUND: Corn grains are commonly contaminated with mycotoxins and fungi. The purpose of this study was to evaluate the reduction of aflatoxins B1 , B2 , G1 , and G2 and the inhibition of Aspergillus niger in corn grains using ultrasound, ultraviolet (UV) radiation, electrolyzed water, and sodium bicarbonate. The determination of aflatoxins was performed by high-performance liquid chromatography with fluorescence detection and postcolumn derivatization, and analysis of A. niger was performed by evaluating mycelial growth in potato dextrose agar. The best treatment for reducing aflatoxins and inhibiting mycelial growth was evaluated in corn contaminated with A. niger. RESULTS: The results show a significant reduction in aflatoxins in the following order: sodium bicarbonate > ultrasound > UV > electrolyzed water for aflatoxins B1 , B2 , and G2 . For aflatoxin G1 , the order of reduction was sodium bicarbonate > ultrasound > electrolyzed water > UV, with maximum values between 70.50% and 87.03% reached with sodium bicarbonate; for the other treatments, the reduction was between 51.51% and 65.44%. Regarding the fungus, the order of inhibition in the control of mycelial growth was sodium bicarbonate > ultrasound > electrolyzed water > UV in corn grains, and inhibition of mycelial growth was obtained at a sodium bicarbonate concentration of 3.0 g L-1 . CONCLUSION: Sodium bicarbonate, electrolyzed water, ultrasound, and UV radiation inhibited the growth of A. niger on potato dextrose agar and reduced the contents of aflatoxins B1 , B2 , G1 , and G2 in vitro. Sodium bicarbonate showed an ability to inhibit mycelial growth in corn grains. © 2020 Society of Chemical Industry.

Volatilome study of the feijoa fruit [Acca sellowiana (O. Berg) Burret.] with headspace solid phase microextraction and gas chromatography coupled with mass spectrometry.

Feijoa is a subtropical bush of the Myrtaceae family. It has unique fruit with organoleptic properties that make it an exotic fruit. Head space solid phase microextraction (HS-SPME) with a 65 µm divinylbenzene/polydimethylsiloxane (DVB/PDMS) fiber and gas chromatography coupled to mass spectrophotometry (GC-MS) was used to study the volatile fraction of feijoa fruit cultured in Caldas, Colombia. The profile analyzed included 134 volatile organic compounds (VOCs). 127 VOCs were classified based on the functional group using the spectral and structural networks correlation analysis. Methyl, ethyl and (Z)-3-hexenyl benzoate with 50% of the volatile composition, were the main compounds. Biosynthesis of the volatilome of feijoa fruit was associated with five main metabolic pathways. This study represents the first analysis of feijoa fruit commercialized in the region. This is an innovator view in elucidation of metabolic pathways that represent the biochemistry of the aroma of this fruit.

Polyphenol Extracts from Three Colombian Passifloras (Passion Fruits) Prevent Inflammation-Induced Barrier Dysfunction of Caco-2 Cells.

Chronic intestinal inflammation is associated with pathophysiology of obesity and inflammatory bowel diseases. Gastrointestinal inflammation increases barrier dysfunction exacerbating the immune response and perpetuating chronic inflammation. Anti-inflammatory flavonoids may prevent this intestinal barrier dysfunction. The purpose of this study was to evaluate the polyphenol composition of Colombian Passiflora edulis var. Flavicarpa (Maracuyá), Passiflora edulis var. Sims (Gulupa), and Passiflora ligularis var. Juss (Granadilla) (passion fruits) and to evaluate their ability to inhibit disruption of intestinal barrier dysfunction of Caco-2 (colorectal adenocarcinoma) cells by an inflammatory cocktail (IC). Polyphenols (flavan-3-ols, phenolic acids, flavonols), xanthenes, and a terpene were identified in passion fruits. Cyanidin 3-rutinoside, (+)-catechin and ferulic acid were the most abundant phenolics in P. edulis var. Flavicarpa, P. edulis var. Sims, and P. ligularis var. Juss, respectively. Fruit extracts prevented loss of transepithelial electrical resistance in Caco-2 cells treated with the IC. Among the extracts, P. ligularis var. Juss was most effective at maintaining Caco-2 transepithelial electrical resistance (TEER) with ~73% relative to the IC-treated cells with about 43% of initial TEER values. This fruit had cyanidin-3-rutinoside, (+)-catechin, (-)-epicatechin, and ferulic acid in its phenolic profile. Results of this work support the hypothesis that consumption of passion fruit extracts could benefit intestinal health.

Identification of volatile compound markers during the ripening and senescence of lulo (Solanum quitoense Lam.).

Lulo (Solanum quitoense Lam.) is an exotic fruit cultivated in Colombia. During ripening and senescence, this climactic fruit undergoes biochemical processes that produce the volatiles responsible for its aroma. This study aimed to evaluate the changes in the volatile content during the ripening and senescence of lulo. Analysis of the volatile composition of lulo harvested in each of its five ripening stages and during its senescence time when stored at 18 ± 2 °C was performed using HS-SPME with GC-MS. Throughout ripening, the most notable change was the transformation of alcohols such as (Z)-3-hexen-1-ol and 1-penten-3-ol to afford esters such as (Z)-3-hexenyl acetate and ketones such as 1-penten-3-one. Some acids reacted with alcohols to produce acetate and hexanoate esters, concentrations which increased more than sixfold between stage one and five. Moreover, all the major compounds were C6 straight chain compounds related to the lipoxygenase pathway. During senescence, majority of compounds were methyl esters, which increased in concentration consistently until day eight. Remarkably, the content of methyl butanoate increased from 0.9% of the total amount of volatiles on day two up to 76.4% on day eight. Some of these volatiles are probably contributors to the "off flavor" during senescence.

Synergistic integration of sonochemical and electrochemical disinfection with DSA anodes.

This work focuses on the disinfection actual urban wastewater by the combination of ultrasound (US) irradiation and electrodisinfection with Dimensionally Stable Anodes (DSA). First, the inactivation of Escherichia coli (E. coli) during the sonochemical disinfection was studied at increasing ultrasound power. Results showed that it was not possible to achieve a complete disinfection, even at the highest US power (200 W) dosed by the experimental device used. Next, the electrodisinfection with DSA anodes at different current densities was studied, finding that it was necessary a minimum current density of 11.46 A m(-2) to reach the complete disinfection. Finally, an integrated sonoelectrodisinfection process was studied. Results showed a synergistic effect when coupling US irradiation with DSA electrodisinfection, with a synergy coefficient higher than 200% of the disinfection rate attained for the highest US power applied. In this process, hypochlorite and chloramines were identified as the main reagents for the disinfection process (neither chlorate nor perchlorate were detected), and the presence of trihalomethanes was far below acceptable values. Confirming this synergistic effect with DSA anodes opens the door to novel efficient disinfection processes, limiting the occurrence of hazardous disinfection by-products.

Determinación de residuos de oxitetraciclina en muestras de carne bovina / Determiation of oxytetracycline residues in samples of boviee meat

El objetivo de este estudio fue determinar la presencia de residuos de oxitetraciclina (OTC) en 149 muestras de músculo diafragmático de bovinos de carne, en una planta de sacrificio comercial en Antioquia (Colombia). Las muestras fueron procesadas y purificadas mediante un sistema de extracción en fase sólida. La detección de OTC se realizó usando cromatografía líquida de alta eficiencia (HPLC), se usó como referencia el Límite Máximo de Residuos (LMR) de la Unión Europea (LMR > 100 ppb). El 49% de las muestras (n = 73) presentaron residuos de OTC; el 8% (n = 12) de las muestras contenían cantidades de OCT superiores al LMR. La edad, la raza y la procedencia no estuvieron asociadas con la presencia de residuos de oxitetraciclina (p > 0,05). Las hembras presentaron una prevalencia más alta de residuos que los machos (p = 0,06). Se concluye que a pesar de que la prevalencia de residuos de OTC en la carne bovina evaluada fue baja, es evidente que se debe fortalecer la implementación de buenas prácticas ganaderas, un sistema de vigilancia epidemiológica y programas de entrenamiento para profesionales, ganaderos y personal responsable de los animales, a fin de garantizar un alimento inocuo al consumidor.

The aim of this study was to determine the presence of oxytetracycline (OTC) residues in 149 samples of diaphragm muscle of beef cattle, in a commercial slaughterhouse in Antioquia (Colombia). The samples were processed and purified through solid phase extraction. OTC detection was performed using high performance liquid chromatography (HPLC), the Maximum Residue Limits (MRL) of the European Union was used as reference (MRL > 100 ppb). Forty-nine percent of the samples (n = 73) presented OTC residues, 8% (n = 12) of samples contained amounts of OTC beyond the MRL. Age, breed and origin were not associated with the presence of oxytetracycline residues (p > 0.05). Prevalence of residues is higher among female than male (p = 0.06). It is concluded that although the prevalence of OTC residues in bovine meat evaluated was low, it is clear that the implementation of good farming practices, a system of epidemiological surveillance and training programs for professionals, livestock producers, and staff responsible for the animals should be strengthened, in order to guarantee safe food to consumers.

Human intestinal mucus proteins isolated by transanal irrigation and proctosigmoidoscopy / Proteínas del moco intestinal humano aislado por irrigación transanal y rectosigmoidoscopia / Proteinas do muco intestinal humano isolado por irrigação transanal e retossigmoidoscopia

Human intestinal mucus essentially consists of a network of Mucin2 glycoproteins embedded in many lower molecular weight proteins. This paper contributes to the proteomic study of human intestinal mucus by comparing two sample collection methods (transanal irrigation and brush cytology during proctosigmoidoscopy) and analysis techniques (electrophoresis and digestion in solution). The entire sample collection and treatment process is explained, including protein extraction, digestion and desalination and peptide characterisation using a nanoAcquity UPLC chromatograph coupled to an HDMS spectrometer equipped with a nanoESI source. Collecting mucus via transanal irrigation provided a larger sample volume and protein concentration from a single patient. The proctosigmoidoscopy sample could be analysed via digestion in solution after depleting albumin. The analysis indicates that a simple mucus lysis method can evaluate the electrophoresis and digestion in solution techniques. Studying human intestinal mucus complexes is important because they perform two essential survival functions for humans as the first biochemical and physical defences for the gastrointestinal tract and a habitat for intestinal microbiota, which are primarily hosted in the colon and exceeds the human genetic information and cell number 100- and 10-fold (1).

El moco intestinal humano está formado, esencialmente, por una red de la glicoproteína Mucina2, en la cual se encuentran inmersas muchas otras proteínas de menor peso molecular. El objetivo principal del presente trabajo es realizar una contribución al estudio proteómico del moco intestinal humano, mediante la comparación de dos métodos de recolección de muestra (irrigación transanal y cepillos de citología durante rectosigmoidoscopia) y de dos técnicas de análisis (electroforesis y digestión en solución). Se explica todo el proceso de recolección y tratamiento de la muestra para extraer las proteínas, la digestión y desalinización de las mismas, hasta llegar a la caracterización de los péptidos en un cromatógrafo nanoAcquity UPLC acoplado a un espectrómetro HDMS, equipado con una fuente nanoESI. La recolección del moco por irrigación transanal aportó mayor volumen de muestra de un solo paciente y mayor concentración de proteínas. La muestra obtenida por rectosigmoidoscopia se pudo analizar por digestión en solución, previa depleción de albúmina. El análisis indica que una metodología sencilla de lisis del moco puede ser utilizada para evaluación por las técnicas de electroforesis y de digestión en solución. El estudio del complejo moco intestinal humano es importante por las dos funciones primordiales que cumple para la supervivencia del ser humano: como la primera línea de defensa bioquímica y física del tracto gastrointestinal, y como el hábitat de la microbiota intestinal, la cual se hospeda principalmente en el colon, y supera en información genética hasta 100x la del humano y en 10x su número de células (1).

O muco intestinal humano está formado essencialmente por uma rede da glicoproteína Mucin2, constituída por outras proteínas de menor massa molecular. O objetivo principal deste trabalho é contribuir ao estudo proteômico do muco mediante a comparação de dois métodos de amostragem (irrigação transanal e escovas de citologia durante retossigmoidoscopia) e dois técnicas de análise (e digestão em solução). São descritos os processos de amostragem, extração, digestão e dessalinização de proteínas até chegar na caracterização dos peptídeos digeridos em um cromatógrafo nanoAcquity UPLC acoplado a um espectrómetro HDMS, equipado com uma fonte nanoESI. A coleta do muco por irrigação transanal forneceu um volume maior de amostra por pessoa e maior concentração de proteínas. As amostras obtidas por retossigmoidoscopia foram analisadas por digestão em solução, após a depleção de albumina. As análises mostraram que uma metodologia simples de lise do muco pode ser utilizada para avaliação mediante as técnicas eletroforese e digestão em solução. O estudo do complexo MIH é importante pelas suas duas funções fundamentais na sobrevivência humana, sendo a primeira linha de defesa bioquimica e física do trato gastrointestinal, e o habitat da microbiota intestinal, hospedada principalmente no cólon e que contem informação genética até 100 X superior à do humano e 10 X seu número de células (1).