Publications by authors named "Laiza Canielas Krause"

7 Publications

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Studies related to the chemical composition, biological activities and toxicity of methanolic extracts of noni () fruits and leaves.

Nat Prod Res 2022 Jan 23:1-4. Epub 2022 Jan 23.

Post Graduate Program in Industrial Biotechnology (PBI), Tiradentes University (UNIT), Aracaju, Sergipe, Brazil.

is a plant that grows in Brazilian northeast and presented a wide range of therapeutic, industrial and technological applications. Based on this, the aim of this work was to study the chemical composition, main biological activities and potential toxicity of its extracts, aiming their industrial application. Important compounds were identified in the methanolic extracts obtained by ultrasonic and Soxhlet extractions from leaves and fruits. GC × GC allowed for the identification of phytosterols, fatty acids and methyl esters, besides others (scopoletin, hydrocarbons, alcohols, terpenes). By HPLC-DAD, compounds like catechin, rutin, quercetin could be also identified and quantified. Their content of polyphenols and flavonoids was considered between the international standards. The extracts showed high antioxidant activities (EC ∼ 300 μg mL, using DPPH assay) compared with those from the literature. The extracts did not show toxicity or mutagenicity, but presented cytotoxicity, which can indicate their use safely in phytotherapic or nutritional applications.
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http://dx.doi.org/10.1080/14786419.2021.2021199DOI Listing
January 2022

Enhanced HCB removal using bacteria from mangrove as post-treatment after electrochemical oxidation using a laser-prepared Ti/RuO-IrO-TiO anode.

Chemosphere 2021 Sep 18;279:130875. Epub 2021 May 18.

Molecular Biology Laboratory, Research and Technology Institute - ITP, Aracaju, SE, Brazil; Industrial Biotechnology Graduation, Universidade Tiradentes, 49032-490, Aracaju, Brazil.

The environmental persistence of hexachlorobenzene (HCB) is a challenge that promotes studies for efficient treatment alternatives to minimize its environmental impact. Here, we evaluated the HCB removal by electrochemical, biological, and combined approaches. The electrochemical treatment of 4 μM HCB solutions was performed using a synthesized Ti/RuO-IrO-TiO anode, while the biological treatment using mangrove-isolated bacteria was at 24, 48, and 72 h. The HCB degradability was assessed by analyzing chemical oxygen demand (COD), microbial growth capacity in media supplemented with HCB as the only carbon source, gas chromatography, and ecotoxicity assay after treatments. The synthesized anode showed a high voltammetric charge and catalytic activity, favoring the HCB biodegradability. All bacterial isolates exhibited the ability to metabolize HCB, especially Bacillus sp. and Micrococcus luteus. The HCB degradation efficiency of the combined electrochemical-biological treatment was evidenced by a high COD removal percentage, the non-HCB detection by gas chromatography, and a decrease in ecotoxicity tested with lettuce seeds. The combination of electrochemical pretreatment with microorganism degradation was efficient to remove HCB, thereby opening up prospects for in situ studies of areas contaminated by this recalcitrant compound.
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http://dx.doi.org/10.1016/j.chemosphere.2021.130875DOI Listing
September 2021

Brazilian Red Propolis: Extracts Production, Physicochemical Characterization, and Cytotoxicity Profile for Antitumor Activity.

Biomolecules 2020 05 6;10(5). Epub 2020 May 6.

Tiradentes University (UNIT), Av. Murilo Dantas, 300, Aracaju 49010-390, Brazil.

Brazilian red propolis has been proposed as a new source of compounds with cytotoxic activity. Red propolis is a resinous material of vegetal origin, synthesized from the bees of the Appis mellifera family, with recognized biological properties. To obtain actives of low polarity and high cytotoxic profile from red propolis, in this work, we proposed a new solvent accelerated extraction method. A complete 2 factorial design was carried out to evaluate the influence of the independent variables or factors (e.g., temperature, number of cycles, and extraction time) on the dependent variable or response (i.e., yield of production). The extracts were analyzed by gas chromatography coupled with mass spectrometry for the identification of chemical compounds. Gas chromatography analysis revealed the presence of hydrocarbons, alcohols, ketones, ethers, and terpenes, such as lupeol, lupenone, and lupeol acetate, in most of the obtained extracts. To evaluate the cytotoxicity profile of the obtained bioactives, the 3-(4,5-dimethyl-2-thiazole)-2,5-diphenyl-2--tetrazolium bromide colorimetric assay was performed in different tumor cell lines (HCT116 and PC3). The results show that the extract obtained from 70 °C and one cycle of extraction of 10 min exhibited the highest cytotoxic activity against the tested cell lines. The highest yield, however, did not indicate the highest cytotoxic activity, but the optimal extraction conditions were indeed dependent on the temperature (i.e., 70 °C).
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http://dx.doi.org/10.3390/biom10050726DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7277404PMC
May 2020

The impact of anthropogenic activity at the tropical Sergipe-Poxim estuarine system, Northeast Brazil: Fecal indicators.

Mar Pollut Bull 2020 May 24;154:111067. Epub 2020 Mar 24.

Federal University of Sergipe, Chemistry Department, São Cristóvão, Sergipe 49100-000, Brazil.

The individual concentrations and sources of sterols in sediments samples collected in two periods 2017 (dry period /March and rainy period/August) were determined along with the Sergipe-Poxim estuarine system, Aracaju, Brazil. The individual sterols concentration ranged from 135 to 21,746 ng g (March) and 191 to 144,748 ng g (August) and the distribution was mainly dominated by β-sitosterol in both periods with 37.2% (March) and 70.8% (August) of the total sterols found. In all the sampling sites, the coprostanol levels were higher than 100 ng g (March) and 500 ng g (August), indicating sewage contamination. Diagnostic ratios between sterols suggested the predominance of sewage sources. Pearson correlation assessed a correlation significant (March) and negligible (August) between coprostanol concentration levels and organic matter. The principal component analysis (PCA) showed that the sterols levels influenced strongly C1, as well as C2 distinguished between the plant sterols and from sewage.
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http://dx.doi.org/10.1016/j.marpolbul.2020.111067DOI Listing
May 2020

Physicochemical and sensory profile of Beauregard sweet potato beer.

Food Chem 2020 May 24;312:126087. Epub 2019 Dec 24.

Institute of Technology and Research (ITP), Av. Murilo Dantas, 300, Aracaju, Sergipe CEP 49032-490, Brazil; Tiradentes University (UNIT), Av. Murilo Dantas, 300, Aracaju, Sergipe CEP 49032-490, Brazil.

Beer has been one of the most consumed alcoholic beverages worldwide. However, the incorporation of adjuncts in the beer can add new organoleptic and functional characteristics to the beverage. For this, Beauregard sweet potato shows high potential due to being a rich source of starch and many bioactive compounds. The aim of this study was to develop the best process condition to produce a Sweet potato beer with enhanced nutritional and antioxidant properties and good sensory characteristics. Beer samples showed increased antioxidant activity especially due to β-carotene and their total phenolic content. The phytochemical profile of sweet potato biocompounds demonstrated a direct effect of this adjunct on sensory and functional characteristics of the finished beer. In conclusion, it was found that Beauregard sweet potato is a promising adjunct for beer brewing with nutraceutical properties due to its rich composition of bioactive compounds.
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http://dx.doi.org/10.1016/j.foodchem.2019.126087DOI Listing
May 2020

Influence of drying methods and agronomic variables on the chemical composition of mate tea leaves (Ilex paraguariensis A. St.-Hil) obtained from high-pressure CO2 extraction.

J Agric Food Chem 2007 Dec 7;55(25):10081-5. Epub 2007 Nov 7.

Universidade Federal do Pampa, 96412-420 Bagé, RS, Brazil.

The main objective of this work is to assess the influence of two drying methods (microwave and vacuum oven) and some agronomic variables (plant fertilization conditions and sunlight intensity) on the characteristics of mate tea (Ilex paraguariensis) leaves extracts obtained from high-pressure carbon dioxide extractions performed in the temperature range from 20 to 40 degrees C and from 100 to 250 bar. Samples of mate were collected in an experiment conducted under agronomic control at Ervateira Barão LTDA, Brazil. Chemical distribution of the extracts was evaluated by gas chromatography coupled with a mass spectrometer detector (GC/MS). In addition to extraction variables, results showed that both sample drying methods and agronomic conditions exert a pronounced influence on the extraction yield and on the chemical distribution of the extracts.
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http://dx.doi.org/10.1021/jf071544oDOI Listing
December 2007

Chemical composition and extraction yield of the extract of Origanum vulgare obtained from sub- and supercritical CO2.

J Agric Food Chem 2004 May;52(10):3042-7

Department of Organic Chemistry, Institute of Chemistry and Geosciences, Federal University of Pelotas, Campus Universitário-Capão do Leão, s/no., Caixa Postal 354, CEP 96010-900 Pelotas, RS, Brazil.

In this work sub- and supercritical CO(2) were used to obtain extracts from two origanum samples, one commercial, and another cultivated under agronomic control. The experiments were performed in the temperature range of 293-313 K and from 100 to 200 bar in pressure, employing around 26 g of origanum samples. Results show that the commercial sample provides a higher yield of extract if compared to the other sample. It is also achieved that a raise in temperature at constant pressure leads to an increase in the extraction yield despite solvent density changes. Chemical analyses were carried out in a GC-MSD, allowing the identification of around 24 compounds by use of the library of spectra of the equipment and injection of some standard compounds for both commercial and cultivated origanum samples. It was also found that the distribution of chemical components as a function of extraction time differs appreciably between the origanum species. The chromatographic analysis permitted the identification of thymol and cis-sabinene hydrate as the most prominent compounds present in commercial oregano sample and carvacrol and cis-sabinene hydrate in the cultivated Origanum vulgare.
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http://dx.doi.org/10.1021/jf030575qDOI Listing
May 2004
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