•Distinctive antioxidant profiles of hydrolysates were discovered by latent profile analysis.•Influence on antioxidant profiles of peptides–phenolic compounds interaction was assessed.•Higher ...cellular antioxidant activity was achieved when phenolics are present along with peptides.•Relationship between the composition of hydrolysates and their antioxidant profile was studied.•Cationic amino acids and hydrolysis degree were directly related to antioxidant cell protection.
The role of the peptides–phenolic compounds (PC) interaction on the antioxidant capacity profile (ACP) of protein hydrolysates from rapeseed (Brassica napus) was studied in 36 hydrolysates obtained from a PC-rich and PC-reduced protein substrate. The latent profile analysis (LPA), with data of seven in vitro methods and one assay for cellular antioxidant activity (CAA), allowed identifying five distinctive groups of hydrolysates, each one with distinctive ACP. The interaction of peptides with naturally present PC diminished in vitro antioxidant activity in comparison with their PC-reduced counterparts. However, CAA increased when peptides–PC interaction occurred. The profile with the highest average CAA (62.41±1.48%), shown by hydrolysates obtained by using alcalase, shared typical values of Cu2+-catalysed β-carotene oxidation (62.41±0.43%), β-carotene bleaching inhibition (91.75±0.22%) and Cu2+-chelating activity (74.53±0.58%). The possibilities for a sample to exhibit ACP with higher CAA increased with each unit of positively charged amino acids, according to multinomial logistic regression analysis.
•Nanofiltration allows purification of free Arg from high molecular weight components.•Arg is purified from nanofiltrated permeate by absorbing to Amberlite IR-120 resin.•Amberlite desorbed Arg is ...finally purified by precipitation or crystallization.
Chickpea is a grain legume widely consumed in the Mediterranean region and other parts of the world. Chickpea seeds are rich in proteins but they also contain a substantial amount of free amino acids, especially arginine. Hence chickpea may represent a useful source of free amino acids for nutritional or pharmaceutical purposes. Arginine is receiving great attention in recent years because it is the substrate for the synthesis of nitric oxide, an important signaling molecule involved in numerous physiological and pathological processes in mammals. In this work we describe a simple procedure for the purification of arginine from chickpea seeds, using nanofiltration technology and an ion-exchange resin, Amberlite IR-120. Arginine was finally purified by precipitation or crystallization, yielding preparations with purities of 91% and 100%, respectively. Chickpea may represent an affordable green source of arginine, and a useful alternative to production by fermentation or protein hydrolysis.
Vicia seeds represent an underutilized source of nutritional and functional components. Besides being rich in proteins, they are also rich in polyphenols, free amino acids, and lectins. These ...components are enriched in a by‐product of the production of protein isolates, a pH 4 soluble extract. Extracts from six Vicia have been analyzed, and NO radical scavenging and antiproliferative activities have been determined. Canavanine was the main free amino acid, while gallic acid derivatives were the most abundant of polyphenols. Fractionation of the extracts by ultrafiltration rendered a lectin‐free fraction that exhibited nitric oxide radical scavenging activity. Based on this activity, and in the presence of high levels of polyphenols and canavanine that are inhibitors of inducible nitric oxide synthase, it is proposed that these extracts may have an immunomodulatory effect. In addition, some extracts inhibited proliferation of cancerous Caco‐2 cells, further supporting the potential of Vicia extracts as functional components.
Practical applications
During the production of Vicia protein isolates an aqueous soluble fraction, considered a by‐product, is generated which is rich in polar polyphenols, free amino acids, and water soluble proteins that are of interest from a functional point of view. In six Vicia species this aqueous fraction showed NO radical scavenging and cell antiproliferative activity. Hence, these fractions usually considered as a by‐product, could be exploited as a source of functional compounds with potential health promoting properties. This could result in the revalorization of Vicia seeds and decrease in the generation of by‐products from the process of Vicia protein isolate productions.
Virus-host interactions determine an infection outcome. The Asian lineage of Zika virus (ZIKV), responsible for the recent epidemics, has fixed a mutation in the NS1 gene after 2012 that enhances ...mosquito infection. Here we report that the same mutation confers NS1 to inhibit interferon-β induction. This mutation enables NS1 binding to TBK1 and reduces TBK1 phosphorylation. Engineering the mutation into a pre-epidemic ZIKV strain debilitates the virus for interferon-β induction; reversing the mutation in an epidemic ZIKV strain invigorates the virus for interferon-β induction; these mutational effects are lost in IRF3-knockout cells. Additionally, ZIKV NS2A, NS2B, NS4A, NS4B, and NS5 can also suppress interferon-β production through targeting distinct components of the RIG-I pathway; however, for these proteins, no antagonistic difference is observed among various ZIKV strains. Our results support the mechanism that ZIKV has accumulated mutation(s) that increases the ability to evade immune response and potentiates infection and epidemics.
The innate antiviral response is integral in protecting the host against virus infection. Many proteins regulate these signaling pathways including ubiquitin enzymes. The ubiquitin-activating (E1), ...-conjugating (E2), and -ligating (E3) enzymes work together to link ubiquitin, a small protein, onto other ubiquitin molecules or target proteins to mediate various effector functions. The tripartite motif (TRIM) protein family is a group of E3 ligases implicated in the regulation of a variety of cellular functions including cell cycle progression, autophagy, and innate immunity. Many antiviral signaling pathways, including type-I interferon and NF-κB, are TRIM-regulated, thus influencing the course of infection. Additionally, several TRIMs directly restrict viral replication either through proteasome-mediated degradation of viral proteins or by interfering with different steps of the viral replication cycle. In addition, new studies suggest that TRIMs can exert their effector functions via the synthesis of unconventional polyubiquitin chains, including unanchored (non-covalently attached) polyubiquitin chains. TRIM-conferred viral inhibition has selected for viruses that encode direct and indirect TRIM antagonists. Furthermore, new evidence suggests that the same antagonists encoded by viruses may hijack TRIM proteins to directly promote virus replication. Here, we describe numerous virus-TRIM interactions and novel roles of TRIMs during virus infections.
A method for determination of the non-protein amino acid l-α-amino-γ-(guanidinooxy)-n-butyric acid (l-canavanine) and other free amino acids in Vicia disperma is presented. Seed extracts were ...derivatized by reaction with diethyl ethoxymethylenemalonate and analyzed by reverse-phase high-performance liquid chromatography. Calibration curves showed very good linearity of the response. The limit of detection and quantification were 0.15 and 0.50μM, respectively. The method has a high intra- (RSD=0.35%) and inter-repeatability (RSD=2.86%), and a remarkable accuracy with a 99% recovery in spiked samples. The method is very easy to carry out and allows for ready analysis of large number of samples using very basic HPLC equipment because the derivatized samples are very stable and have very good chromatographic properties.
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•Determination of l-canavanine by reverse phase HPLC of DEEMM derivative.•Other free amino acids are also determined.•DEEMM derivatives are stable and have very good chromatographic properties.•Precision, accuracy, and repeatability are excellent in a large linear range.•Analysis of l-canavanine and free amino acids in V. disperma has been carried out.
Malaria vector species in Colombia: a review Montoya-Lerma, James; Solarte, Yezid A; Giraldo-Calderón, Gloria Isabel ...
Memórias do Instituto Oswaldo Cruz
106 Suppl 1, Issue:
suppl 1
Journal Article
Peer reviewed
Open access
Here we present a comprehensive review of the literature on the vectorial importance of the major Anopheles malaria vectors in Colombia. We provide basic information on the geographical distribution, ...altitudinal range, immature habitats, adult behaviour, feeding preferences and anthropophily, endophily and infectivity rates. We additionally review information on the life cycle, longevity and population fluctuation of Colombian Anopheles species. Emphasis was placed on the primary vectors that have been epidemiologically incriminated in malaria transmission: Anopheles darlingi, Anopheles albimanus and Anopheles nuneztovari. The role of a selection of local, regional or secondary vectors (e.g., Anopheles pseudopunctipennis and Anopheles neivai) is also discussed. We highlight the importance of combining biological, morphological and molecular data for the correct taxonomical determination of a given species, particularly for members of the species complexes. We likewise emphasise the importance of studying the bionomics of primary and secondary vectors along with an examination of the local conditions affecting the transmission of malaria. The presence and spread of the major vectors and the emergence of secondary species capable of transmitting human Plasmodia are of great interest. When selecting control measures, the anopheline diversity in the region must be considered. Variation in macroclimate conditions over a species' geographical range must be well understood and targeted to plan effective control measures based on the population dynamics of the local Anopheles species.
El presente artículo describe una propuesta de aula desarrollada en el curso de Historia del diseño de la Fundación Universitaria Bellas Artes y el Instituto Tecnológico Metropolitano, dos ...universidades de Medellín, Colombia. La propuesta recurre al concepto de educación y currículo expandido para llevar a cabo un ejercicio que busca generar nuevos sentidos de apropiación de lo patrimonial a través de narrativas visuales, articulando las redes sociales, las tecnologías digitales simples y el patrimonio fotográfico de la ciudad para el reconocimiento del espacio urbano como generador y constructor de memoria colectiva. Se concluye que la fotografía patrimonial tiene la capacidad de ilustrar la vida de las pequeñas historias que componen una memoria colectiva y una historia no lineal, lo que produce en los estudiantes relaciones significativas con el pasado de su ciudad, además de cautivarlos en el ejercicio investigativo.
•Chickpea protein concentrates are potential sources of healthy isoflavones.•Protein concentrates are enriched in isoflavones as compared to the original flour.•Derivatives of biochanin A represent ...90% w/w isoflavones in flour (9 µg/g).•Biochanin A aglycone represents 93% w/w isoflavones in concentrates (31 µg/g).•Formononetin and genistein were also present at much lower concentration.
The isoflavones in chickpea concentrates were analysed and compared to the original flour. Protein concentrates were prepared by alkaline extraction and precipitation of protein at the isoelectric pH. HPLC analysis revealed that the concentrates were enriched in isoflavones. The concentration of total isoflavones was 45 and 10 µg/g in concentrates and flour, respectively. Isoflavones in flour were hydrolyzed to the corresponding aglycones during alkaline extraction. While hydrolyzable derivatives of biochanin A represent 90% (w/w) total isoflavones in flour (9 µg/g), biochanin A aglycone was the major isoflavone in concentrates (31 µg/g). Minor components were formononetin, genistein, and the flavonol kaempferol. Thus, chickpea protein concentrates represent an even better source of health-promoting isoflavones than the original chickpea.
Annona montana Macfad is a fruit species of the Annonaceae family. In this study, the phytochemical potential of A. montana seeds was investigated. Ethanol and hexane extracts from seeds were ...evaluated for cytotoxicity and insecticidal activity, phenolic content, and antioxidant capacity. The latter being related to free radical scavenging activity assay (DPPH) and ferric reducing power (FRAP). Exposing Artemia salina to both seed extract types reveled their high toxicity with a median lethal concentration (LC50) of < 10 μg mL-1. Further A. montana seed insecticidal activity was evaluated against Thrips tabaci L., revealing that the most promising treatments were observed for a concentration of 100 mg L-1 in both extracts. The ethanol extract resulted in a mortality of 67.5 % and the hexane extract in a 53.3 % mortality. The ethanolic extract of A. montana seeds showed the highest total phenolic content: 297.38 mg GAE/100 g of dried extract and 192.66 mg TE/100 g, and 385.46 mg TE/100 g for DPPH and FRAP, respectively. The chemical characterization of both extracts by high performance liquid chromatography (HPLC) revealed the presence of acetogenins. The results obtained idicate that the A. montana extracts are a promising source of compounds with insecticidal activity.
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