The influence of ripening stage and cultivation system on the total antioxidant activity and total phenolic compounds of yellow passion fruit pulp

BACKGROUND: This work aimed to investigate the influence of both ripening stage and cultivation system on the total phenolic compounds (TPC) and total antioxidant activity (TAA) of passion fruit pulp. TPC extraction was optimized using a 2³ central composed design. The variables were fruit pulp volume, methanol volume and extraction solution volume. TPC was determined using the Folin–Ciocalteu reaction, and TAA using the ABTS radical reaction. RESULTS: The conditions to extract TPC were 2 mL passion fruit pulp and 9 mL extraction solution containing 40% methanol:water (v/v). TPC values increased in the passion fruit pulp during ripening for both cultivation systems, ranging from 281.8 to 361.9 mg gallic acid L^?1 (P?0.05) for the organic pulp and from 291.0 to 338.6 mg gallic acid L^?1 (P?0.05) for the conventional pulp. CONCLUSION: TPC values increased during ripening for both organic and conventional passion fruit. The same was true for TAA values for conventional passion fruit. For organic passion fruit, however, TAA values were highest at the initial ripening stages. These results suggest that antioxidant compounds exert strong influence on the initial ripening stages for organic passion fruit, when TPC still did not reach its maximum level. Copyright © 2012 Society of Chemical Industry     

Assessment of chemical mixtures and groundwater effects on Daphnia magna transcriptomics

Small organisms can be used as biomonitoring tools to assess chemicals in the environment. Chemical stressors are especially hard to assess and monitor when present as complex mixtures. Here, fifteen polymerase chain reaction assays targeting Daphnia magna genes were calibrated to responses elicited in D. magna exposed for 24 h to five different doses each of the munitions constituents 2,4,6-trinitrotoluene, 2,4-dinitrotoluene, 2,6-dinitrotoluene, trinitrobenzene, dinitrobenzene, or 1,3,5-trinitro-1,3,5-triazacyclohexane. A piecewise-linear model for log-fold expression changes in gene assays was used to predict response to munitions mixtures and contaminated groundwater under the assumption that chemical effects were additive. The correlations of model predictions with actual expression changes ranged from 0.12 to 0.78 with an average of 0.5. To better understand possible mixture effects, gene expression changes from all treatments were compared using high-density microarrays. Whereas mixtures and groundwater exposures had genes and gene functions in common with single chemical exposures, unique functions were also affected, which was consistent with the nonadditivity of chemical effects in these mixtures. These results suggest that, while gene behavior in response to chemical exposure can be partially predicted based on chemical exposure, estimation of the composition of mixtures from chemical responses is difficult without further understanding of gene behavior in mixtures. Future work will need to examine additive and nonadditive mixture effects using a much greater range of different chemical classes in order to clarify the behavior and predictability of complex mixtures.     

Poly(lactic acid) biocomposites with mango waste and organo-montmorillonite for packaging

Poly(lactic acid) (PLA) is a biodegradable polymer used in packaging, but its properties can be improved by manufacturing composite matrixes. The combination of PLA, starch, and nano-montmorillonite leads to materials with superior mechanical properties. Mango lump is rich in cellulose and starch. The goal of this study is to develop and characterize biocomposites based on PLA, mango waste, and nano-organo-montmorillonite for packaging. The samples were microstructurally, morphologically, and mechanically characterized. Physical interaction between the phases was observed. The mango components displaced the PLA X-ray diffraction peaks and the clays altered their intensity, by interfering with chain packing. The addition of single components to PLA increased the samples’ transition temperatures, but the addition of multiple components diminished them. PLA showed adhesiveness to cellulose fibers and nonadhesiveness to starch granules. Thicker samples presented better mechanical properties. PLA–mango–“chocolate clay” samples are relatively stable materials, while PLA–mango–“bofe clay” samples could represent promising highly biodegradable materials. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47512.     

Effect of vitamin A supplementation on iron status in humans: A systematic review and meta-analysis

Anemia is a worldwide public health problem that can be related to many causes, including vitamin A deficiency. The aim of this study was to assess and estimate the effect of vitamin A supplementation (VAS) on iron status biomarkers and anemia in humans. Six databases, including Cochrane, EMBASE, LILACS, Pubmed, Scopus and Web of Science, were searched for clinical trials and cohort studies that investigated the effect of vitamin A supplementation alone on iron status and anemia, without time-restriction. The search yielded 23 eligible studies, 21 clinical trials and 2 cohort studies, with children, teenagers, pregnant or lactating women. The meta-analysis of the clinical trials showed that VAS reduces the risk of anemia by 26% and raises hemoglobin levels, compared to non-treated group, independent of the life stage. VAS did not alter the prevalence of iron deficiency among the clinical trials conducted with children and teenagers (RR 0.82, 95% CI 0.60 to 1.12, p = 0.204), whereas a significant increase in serum ferritin levels was observed in trials conducted with pregnant and lactating women (WMD 6.61 μg/L; 95% CI 6.00 to 7.21 μg/L; p < 0.001). Therefore, vitamin A supplementation alone may reduce the risk of anemia, by improving hemoglobin and ferritin levels in individuals with low serum retinol levels.     

Mechanisms of manganese bioremediation by microbes: an overview

Although an important micronutrient for many living organisms, manganese (Mn) can become a health and environmental problem at high concentrations. The element is usually found in wastewaters and drainages of different industrial sectors and its removal is notoriously difficult because of the high stability of the Mn (II) ion in aqueous solutions. The treatment of Mn‐laden wastewaters may include microorganisms that catalyze Mn oxidation by either enzymatic or non‐enzymatic pathways. In this context, this mini‐review discusses the mechanisms by which fungi and bacteria promote Mn bioremediation. © 2016 Society of Chemical Industry     

Toward persistent autonomous intervention in a subsea panel

Intervention autonomous underwater vehicles (I-AUVs) have the potential to open new avenues for the maintenance and monitoring of offshore subsea facilities in a cost-effective way. However, this requires challenging intervention operations to be carried out persistently, thus minimizing human supervision and ensuring a reliable vehicle behaviour under unexpected perturbances and failures. This paper describes a system to perform autonomous intervention—in particular valve-turning—using the concept of persistent autonomy. To achieve this goal, we build a framework that integrates different disciplines, involving mechatronics, localization, control, machine learning and planning techniques, bearing in mind robustness in the implementation of all of them. We present experiments in a water tank, conducted with Girona 500 I-AUV in the context of a multiple intervention mission. Results show how the vehicle sets several valve panel configurations throughout the experiment while handling different errors, either spontaneous or induced. Finally, we report the insights gained from our experience and we discuss the main aspects that must be matured and refined in order to promote the future development of intervention autonomous vehicles that can operate, persistently, in subsea facilities.