Combining eutectic solvents and pressurized liquid extraction coupled in-line with solid-phase extraction to recover, purify and stabilize anthocyanins from Brazilian berry waste

Pressurized techniques are straightforward for high-scale applications and highly controllable, which seems an excellent strategy for recovering unstable natural compounds. In this work, the main advance was the development of a platform based on the pressurized liquid extraction coupled in-line with a solid-phase extraction step (PLE-SPE) combined with the use of eutectic mixtures as solvents to promote an efficient extraction and purification of natural pigments from food wastes. Eutectic mixtures, conventionally known as (deep) eutectic solvents – (D)ES, are combinations of two or more substances with a lower melting point than any of their components. (D)ES are often referred as “green solvents” because they can potentially be more environmentally friendly than other solvents, especially volatile organic solvents (VOSs). Overall, (D)ES have the potential to contribute to the achievement of several of the SDGs (especially 3, 13, and 14) through their positive impacts on health, environment, and sustainable production and consumption practices. Thus, in this work, (D)ES were used as solvents to valorize Brazilian berry waste (Plinia cauliflora). Anthocyanins are the biomass's main compounds of commercial interest, mainly for food and cosmetic applications. However, there are several technological issues regarding color control due to their high sensitivity to light, heat, oxygen, and pH variations. Thus, the data achieved in this work highlighted the high efficiency and low environmental footprint of the PLE-SPE-(D)ES platform developed. The success of the downstream process here developed was proved by the high extraction efficiency and the purity level of the anthocyanins obtained. Besides, thermal stability analysis was evaluated, demonstrating that (D)ES are not only solvents but also stabilizing agents, improving the shelf-life of the extracted colorants.publishe

Potential application for antimicrobial and antileukemic therapy of a flavonoid-rich fraction of Camellia sinensis

The antimicrobial and antileukemic effect of a purified fraction of flavonoids from the leaves of Camellia sinensis was evaluated. An extraction yield of 9.77 mg.g-1 total flavonoids was recovered through a pressurized liquid extraction associated with solid-phase extraction. This fraction was tested against pathogenic microorganisms (Staphylococcus, Salmonella, and Enterococcus), considering the minimum inhibitory concentration. In addition, the human monocyte cell line THP-1, derived from a patient with acute monocytic leukemia, was used for the antitumor assay. The results show that the flavonoid-rich fraction obtained by coupling a Pressurized Liquids Extraction in-line with a Solid Phase Extraction (PLE-SPE) has a high antimicrobial effect and resulted in cell cycle blockage G0 / G1, increased DNA fragmentation, and altered leukemic cell morphology. These results suggest that a flavonoid-rich fraction obtained from Camellia sinensis can be applied as potential adjuvants in chemotherapy treatment to mitigate the side effects caused by chemotherapy or even as a supplement to cancer therapy9 página

Mechanistic aspects of glycerol electrooxidation on Pt(111) electrode in alkaline media

Glycerol electrooxidation reaction (GEOR) in alkaline media was studied on the Pt(111) electrode with in situ FTIR and electrochemical methods. Cyclic voltammogram profiles display strong electrode deactivation after the first potential scan. Chronoamperometric pulses demonstrate that the deactivation is a result of the reaction intermediates yielded during the faradaic process. In situ FTIR shows evidence that the strongly adsorbed intermediate formed during GEOR is an acyl species which remains present on the surface within the potential window studied.This work was supported by CNPq (projects 474590/2013-5 and 456758/2014-3), FAPESP (project 2013/13749-0) and Capes for the financial support

Seroprevalence of Kaposi Sarcoma–associated Herpesvirus and Other Serologic Markers in the Brazilian Amazon

To determine the presence of Kaposi sarcoma–associated herpesvirus (KSHV) and other serologic markers, we tested serum specimens of 339 Amerindians, 181 rural non-Amerindians, and 1,133 urban blood donors (13 Amerindians) in the Brazilian Amazon. High KSHV seroprevalence in children and inverse association with herpes simplex virus type 2 indicates predominant nonsexual transmission among Amerindians

[Covid-19 in the Northeast of Brazil: from lockdown to the relaxation of social distancing measures].

Even in the period when the Covid-19 pandemic was on the rise in the Northeast of Brazil, the relaxation of social distancing measures was introduced. The scope of the study is to assess, in the light of the epidemiological-sanitary situation in the region, the suitability of relaxation of social distancing measures. Based on the WHO guidelines for relaxation of social distancing, operational indicators were created and analyzed for each guideline in the context of the Northeast. To analyze the behavior of the epidemic, according to selected indicators, Joinpoint trend analysis techniques, heat maps, rate ratios and time trends between capitals and the state interior were compared. The weekly growth peak of the epidemic occurred in May-July 2020 (epidemiological weeks 19 to 31). In most capitals, there was no simultaneous downward trend in the number of cases and deaths in the 14 days prior to flexibilization. In all states the number of tests performed was insufficient. In epidemiological week 24, the state percentages of ICU/Covid-19 bed occupancy were close to or above 70%. The epidemiological situation of the nine Northeastern state capitals analyzed here did not meet criteria and parameters recommended by the World Health Organization for the relaxation of social distancing measures

Glucose- but Not Rice-Based Oral Rehydration Therapy Enhances the Production of Virulence Determinants in the Human Pathogen Vibrio cholerae

Despite major attempts to prevent cholera transmission, millions of people worldwide still must address this devastating disease. Cholera research has so far mainly focused on the causative agent, the bacterium Vibrio cholerae, or on disease treatment, but rarely were results from both fields interconnected. Indeed, the treatment of this severe diarrheal disease is mostly accomplished by oral rehydration therapy (ORT), whereby water and electrolytes are replenished. Commonly distributed oral rehydration salts also contain glucose. Here, we analyzed the effects of glucose and alternative carbon sources on the production of virulence determinants in the causative agent of cholera, the bacterium Vibrio cholerae during in vitro experimentation. We demonstrate that virulence gene expression and the production of cholera toxin are enhanced in the presence of glucose or similarly transported sugars in a ToxR-, TcpP- and ToxT-dependent manner. The virulence genes were significantly less expressed if alternative non-PTS carbon sources, including rice-based starch, were utilized. Notably, even though glucose-based ORT is commonly used, field studies indicated that rice-based ORT performs better. We therefore used a spatially explicit epidemiological model to demonstrate that the better performing rice-based ORT could have a significant impact on epidemic progression based on the recent outbreak of cholera in Haiti. Our results strongly support a change of carbon source for the treatment of cholera, especially in epidemic settings