31 research outputs found
Optimisation of Accelerated Solvent Extraction of Antioxidant Compounds from Rosemary (Rosmarinus officinalis L.), Marjoram (Origanum majorana L.) and Oregano (Origanum vulgare L.) Using Response Surface Methodology
The present study optimised the accelerated solvent extraction (ASE) conditions (Dionex ASE® 200, USA) to maximise the antioxidant capacity of the extracts from three spices of Lamiaceae family; rosemary, oregano and marjoram. Optimised conditions with regard to extraction temperature (66–129 °C) and solvent concentration (32–88% methanol) were identified using response surface methodology (RSM). For all three spices results showed that 129 °C was the optimum temperature in order to obtain extracts with high antioxidant activity. Optimal methanol concentrations with respect to the antioxidant activity of rosemary and marjoram extracts were 56% and 57% respectively. Oregano showed a different response to the effect of methanol concentration and was optimally extracted at 33%. The antioxidant activity yields of the optimal ASE extracts were significantly (p \u3c 0.05) higher than solid/liquid extracts. The predicted models were highly significant (p \u3c 0.05) for both total phenol (TP) and ferric reducing antioxidant property (FRAP) values in all the spices with high regression coefficients (R2) ranging from 0.952 to 0.999
Antioxidant Activity of Spice Extracts and Phenolics in Comparison to Synthetic Antioxidants
The antioxidant capacity of 30 spices used frequently in ready meals and a selection of key compounds from spices were investigated in the current study using ferric reducing antioxidant properties (FRAP), 2,2\u27-azinobis(3-ethylebenzothiaziline-6-sulfonate) (ABTS) and microsomal lipid peroxidation (MLP) assays. Antioxidant capacities of the spice extracts were compared to 5 popular synthetic antioxidants [buylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), tert-butylated hydroquinone (TBHQ), propyl gallate (PG) and octyl gallate (OG)]. Results showed that clove extracts had the highest antioxidant capacity as measured by FRAP, ABTS and MLP assays. Extracts from garlic powder were the lowest ranked of all the spices examined. Synthetic antioxidants were ranked in the following decreasing order of antioxidant activity PG \u3e BHA \u3e TBHQ \u3e OG \u3e BHT. Rosmarinic acid, a polyphenol commonly found in lamiaceae spices and eugenol from clove had higher antioxidant capacities than that of all synthetic antioxidants investigated. Antioxidant capacities of kaempferol from apiaceae spices, capsaicin from chilli, curcumin from turmeric, thymol from thyme and gingerol from ginger were also comparable to most of the synthetic antioxidants
Characterization of Phenolics Composition in Lamiaceae Spices by LC-ESI-MS/MS
A total of 38 phenolic compounds in the solid/liquid extracts of five Lamiaceae spices such as rosemary, oregano, sage, basil and thyme were identified in the present study using LC-ESI-MS/MS. These compounds were distributed in four major categories namely hydroxycinnamic acid derivatives, hydroxybenzoic acid derivatives, flavonoids and phenolic terpenes. Among them, the category of flavonoids was the largest with 17 compounds. Identification of the phenolic compounds was carried out by comparing retention times and mass spectra with those of authentic standards. In case of unavailability of standards, phenolic compounds were identified based on accurate mass of pseudomolecular [M-H]- ions and tandem mass spectrometry (MS/MS) data. The results of accurate mass measurements fitted well with the elemental composition of the compounds. The diagnostic fragmentation patterns of the compounds during collision induced dissociation (CID) elucidated structural information of the compounds analysed
Optimization of Ultrasound Assisted Extraction of Antioxidant Compounds from Marjoram (Origanum majorana L.) Using Response Surface Methodology
The present study optimized the ultrasound assisted extraction (UAE) conditions to maximize the antioxidant activity [Ferric ion Reducing Antioxidant Power (FRAP)], total phenol content (TP) and content of individual polyphenols of extracts from marjoram. Optimal conditions with regard to amplitude of sonication (24.4–61.0 μm) and extraction temperature (15–35 °C) and extraction time (5–15 min) were identified using response surface methodology (RSM). The results showed that the combined treatment conditions of 61 μm, 35 °C and 15 min were optimal for maximizing TP, FRAP, rosmarinic acid, luteolin-7-O-glucoside, apigenin-7-O-glucoside, caffeic acid, carnosic acid and carnosol values of the extracts. The predicted values from the developed quadratic polynomial equation were in close agreement with the actual experimental values with low average mean deviations (E%) ranging from 0.45% to 1.55%. The extraction yields of the optimal UAE were significantly (p \u3c 0.05) higher than solid/liquid extracts. Predicted models were highly significant (p \u3c 0.05) for all the parameters studied with high regression coefficients (R2) ranging from 0.58 to 0.98
High pressure processing on microbial inactivation, quality parameters and nutritional quality indices of mackerel fillets
peer-reviewedThe objective of this study was to investigate the effect of high pressure processing (HPP) (100, 300 or 500 MPa for 2 or 5 min) on microbial inactivation, quality parameters and nutritional quality indices of mackerel fillets. A significant reduction in TVC and H2S-producing bacteria was detected at 300 MPa for 5 min and 500 MPa for 2 or 5 min. Lightness (L*) increased and redness (a*) decreased at the highest treatment intensities. Hardness, chewiness and springiness increased with the most intense treatments but neither cohesiveness nor TBARS values were affected by pressurization. HPP significantly decreased levels of EPA, PUFAs, HUFAs, DHA, CLAs and increased MUFAs and SFAs. TI significantly increased at the highest pressurization intensities and AI was affected when HPP was held for 5 min. However, the ratio PUFA/SFA above 0.45 in pressurized mackerel fillets indicated that HPP did not compromise the nutritional value of this pelagic fish. Industrial relevanceThe potential of HPP to inhibit spoilage and increase the shelf-life of mackerel fillets, while maintaining its quality and healthy attributes, could help the fish processing industry to ensure better quality raw material for further processing, thereby enabling the development of new, value-added products with extended shelf- life. The reduction in the processing time with the subsequent saving of energy compared to conventional thermal methods makes HPP a relatively energy efficient and suitable preservation treatment for the fish industry
Sexual dimorphism in the meiotic requirement for PRDM9: A mammalian evolutionary safeguard.
In many mammals, genomic sites for recombination are determined by the histone methyltransferase PRMD9. Some mouse strains lacking PRDM9 are infertile, but instances of fertility or semifertility in the absence of PRDM9 have been reported in mice, canines, and a human female. Such findings raise the question of how the loss of PRDM9 is circumvented to maintain fertility. We show that genetic background and sex-specific modifiers can obviate the requirement for PRDM9 in mice. Specifically, the meiotic DNA damage checkpoint protein CHK2 acts as a modifier allowing female-specific fertility in the absence of PRDM9. We also report that, in the absence of PRDM9, a PRDM9-independent recombination system is compatible with female meiosis and fertility, suggesting sex-specific regulation of meiotic recombination, a finding with implications for speciation
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A systematic review of computer-based softwares for educating patients with coronary heart disease
Objective: To evaluate the use of computer-based softwares for educating patients with coronary heart disease.
Methods: A systematic electronic search for randomised controlled trials and comparison studies published from 1999 to the end of 2005 using the MEDLINE (1999–2005), EMBASE (1999–2005) and CINAHL (1999–2005) was carried out. Articles including the reference lists in the following journals were hand-searched: Patient Education and Counselling and Patient Counselling and Health Education.
Results: A total of 487 articles were identified. Based on a review of abstracts, five studies fulfilled the inclusion criteria of the review. A scoring sheet was used to assess the papers’ quality. All studies reported significantly increased knowledge in patients using the educational software when compared to standard education. The difference in knowledge between the intervention and control groups remained high even at 6 months follow up. Furthermore, patients reported high satisfaction with the educational programs.
Conclusion: Despite there only being five studies that met the inclusion criteria, this review supports the successful use of computer software to increase knowledge in patients with coronary heart disease. The reviewed articles reveal that computer-based education has an important role in increasing patients’ knowledge about their condition.
Practical implications: It is commonly reported that patients want more information about their illness. This study shows that computerbased education can be a useful, acceptable to patients and effective way to deliver education about coronary heart disease
Multi-omics analysis identifies drivers of protein phosphorylation.
BACKGROUND: Phosphorylation of proteins is a key step in the regulation of many cellular processes including activation of enzymes and signaling cascades. The abundance of a phosphorylated peptide (phosphopeptide) is determined by the abundance of its parent protein and the proportion of target sites that are phosphorylated.
RESULTS: We quantified phosphopeptides, proteins, and transcripts in heart, liver, and kidney tissue samples of mice from 58 strains of the Collaborative Cross strain panel. We mapped ~700 phosphorylation quantitative trait loci (phQTL) across the three tissues and applied genetic mediation analysis to identify causal drivers of phosphorylation. We identified kinases, phosphatases, cytokines, and other factors, including both known and potentially novel interactions between target proteins and genes that regulate site-specific phosphorylation. Our analysis highlights multiple targets of pyruvate dehydrogenase kinase 1 (PDK1), a regulator of mitochondrial function that shows reduced activity in the NZO/HILtJ mouse, a polygenic model of obesity and type 2 diabetes.
CONCLUSIONS: Together, this integrative multi-omics analysis in genetically diverse CC strains provides a powerful tool to identify regulators of protein phosphorylation. The data generated in this study provides a resource for further exploration
The chromatin remodeler p400 ATPase facilitates Rad51-mediated repair of DNA double-strand breaks
DNA damage signaling and repair take place in a chromatin context. Consequently, chromatin-modifying enzymes, including adenosine triphosphate–dependent chromatin remodeling enzymes, play an important role in the management of DNA double-strand breaks (DSBs). Here, we show that the p400 ATPase is required for DNA repair by homologous recombination (HR). Indeed, although p400 is not required for DNA damage signaling, DNA DSB repair is defective in the absence of p400. We demonstrate that p400 is important for HR-dependent processes, such as recruitment of Rad51 to DSB (a key component of HR), homology-directed repair, and survival after DNA damage. Strikingly, p400 and Rad51 are present in the same complex and both favor chromatin remodeling around DSBs. Altogether, our data provide a direct molecular link between Rad51 and a chromatin remodeling enzyme involved in chromatin decompaction around DNA DSBs
Global prevalence and genotype distribution of hepatitis C virus infection in 2015 : A modelling study
Publisher Copyright: © 2017 Elsevier LtdBackground The 69th World Health Assembly approved the Global Health Sector Strategy to eliminate hepatitis C virus (HCV) infection by 2030, which can become a reality with the recent launch of direct acting antiviral therapies. Reliable disease burden estimates are required for national strategies. This analysis estimates the global prevalence of viraemic HCV at the end of 2015, an update of—and expansion on—the 2014 analysis, which reported 80 million (95% CI 64–103) viraemic infections in 2013. Methods We developed country-level disease burden models following a systematic review of HCV prevalence (number of studies, n=6754) and genotype (n=11 342) studies published after 2013. A Delphi process was used to gain country expert consensus and validate inputs. Published estimates alone were used for countries where expert panel meetings could not be scheduled. Global prevalence was estimated using regional averages for countries without data. Findings Models were built for 100 countries, 59 of which were approved by country experts, with the remaining 41 estimated using published data alone. The remaining countries had insufficient data to create a model. The global prevalence of viraemic HCV is estimated to be 1·0% (95% uncertainty interval 0·8–1·1) in 2015, corresponding to 71·1 million (62·5–79·4) viraemic infections. Genotypes 1 and 3 were the most common cause of infections (44% and 25%, respectively). Interpretation The global estimate of viraemic infections is lower than previous estimates, largely due to more recent (lower) prevalence estimates in Africa. Additionally, increased mortality due to liver-related causes and an ageing population may have contributed to a reduction in infections. Funding John C Martin Foundation.publishersversionPeer reviewe