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1.
Molecules ; 28(20)2023 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-37894564

RESUMEN

Sustainable development goals require a reduction in the existing heavy reliance on fossil resources. Forestry can be considered a key resource for the bioeconomy, providing timber, energy, chemicals (including fine chemicals), and various other products. Besides the main product, timber, forestry generates significant amounts of different biomass side streams. Considering the unique and highly complex chemical composition of coniferous needle/greenery biomass, biorefinery strategies can be considered as prospective possibilities to address top segments of the bio-based value pyramid, addressing coniferous biomass side streams as a source of diverse chemical substances with applications as the replacement of fossil material-based chemicals, building blocks, food, and feed and applications as fine chemicals. This study reviews biorefinery methods for coniferous tree forestry biomass side streams, exploring the production of value-added products. Additionally, it discusses the potential for developing further biorefinery strategies to obtain products with enhanced value.


Asunto(s)
Agricultura Forestal , Ríos , Estudios Prospectivos , Biocombustibles , Alimentos , Biomasa
2.
Plants (Basel) ; 11(24)2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36559628

RESUMEN

Procyanidins are a polyphenolic group that can be found in a variety of foods such as chocolate, tea, cranberries and others. Type A procyanidins can be found in a handful of sources and one of the richest sources are American cranberries. These compounds possess antioxidative, anticancer and anti-inflammatory activities and are most widely used as prevention for urinary tract infections. Cranberries are utilized for jam and juice production, and the latter produces industrial food waste press residues. Press residues contain free and bound procyanidins which can be extracted for use as nutraceuticals. In this study, the extraction of cranberry press residues has been optimized using RSM and the resulting extracts have been purified and fractionated. The obtained procyanidin fractions have been investigated for their antioxidative potential and analyzed using LC-ESI-FTICR-HRMS to determine individual procyanidins. The optimization showed that the optimal extraction can be conducted using acetone in a concentration of 53% without the addition of an acidifying agent. Strong correlation was observed for procyanidin contents and their antioxidative activity using DPPH, ABTS and FRAP methods. The purified fractions contained 78 individual (65 Type A) procyanidins with the degree of polymerization of up to 9.

3.
Front Plant Sci ; 13: 980427, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36204062

RESUMEN

Cuticle is the first layer protecting plants against external biotic and abiotic factors and is responsive to climatic factors as well as determined by genetic adaptations. In this study, the chemical composition of bilberry fruit cuticular wax was investigated through a latitudinal gradient from Latvia (56°N 24°E) through Finland (65°N 25°E) to northern Norway (69°N 18°E) in two seasons 2018 and 2019. Changes in the major cuticular wax compounds, including triterpenoids, fatty acids, alkanes, aldehydes, ketones, and primary alcohols, were detected by GC-MS analysis. Generally, a decreasing trend in the proportion of triterpenoids from southern to northern latitudes, accompanied with an increase in proportion of fatty acids, aldehydes, and alkanes, in bilberry fruit cuticular wax was observed. A correlation analysis between climatic factors with proportion of wax compounds indicated that temperature was the main factor affecting the cuticular wax composition in bilberries. A controlled phytotron experiment with southern and northern bilberry ecotypes confirmed the major effect of temperature on bilberry fruit cuticular wax load and composition. Elevated temperature increased wax load most in berries of northern ecotypes. The level of triterpenoids was higher, while levels of fatty acids and alkanes were lower, in wax of bilberry fruits ripened at 18°C compared to 12°C in both northern and southern ecotypes. Based on our results, it can be postulated that the predicted increase in temperature due to climate change leads to alterations in fruit cuticular wax load and composition. In northern ecotypes, the alterations were especially evident.

4.
World J Microbiol Biotechnol ; 38(7): 117, 2022 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-35597812

RESUMEN

Microplastics are one of the major contaminants of aquatic nature where they can interact with organic and inorganic pollutants, including trace metals, and adsorb them. At the same time, after the microplastics have entered the aquatic environments, they are quickly covered with a biofilm - microorganisms which are able to produce extracellular polymeric substances (EPS) that can facilitate sorption of trace metals from surrounding water. The microbial community of biofilm contains bacteria which synthesizes EPS with antimicrobial activity making them more competitive than other microbial inhabitants. The trace metal trapping by bacterial EPS can inhibit the development of certain microorganisms, therefore, a single microparticle participates in complex interactions of the diverse elements surrounding it. The presented review aims to consider the variety of interactions associated with the adsorption of trace metal ions on the surface of microplastics covered with biofilm, the fate of such microplastics and the ever-increasing risk to the environment caused by the combination of these large-scale pollutants - microplastics and trace metals. Since aquatic pollution problems affect the entire planet, strict regulation of the production, use, and disposal of plastic materials is needed to mitigate the effects of this emerging pollutant and its complexes could have on the environment and human health.


Asunto(s)
Contaminantes Ambientales , Oligoelementos , Contaminantes Químicos del Agua , Biopelículas , Humanos , Microplásticos , Plásticos , Contaminantes Químicos del Agua/análisis
5.
J Environ Manage ; 304: 114261, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34923410

RESUMEN

The European Union is currently in the process of transformation toward a circular economy model in which different areas of activity should be integrated for more efficient management of raw materials and waste. The wastewater sector has a great potential in this regard and therefore is an important element of the transformation process to the circular economy model. The targets of the circular economy policy framework such as resource recovery are tightly connected with the wastewater treatment processes and sewage sludge management. With this in view, the present study aims to review existing indicators on resource recovery that can enable efficient monitoring of the sustainable and circular solutions implemented in the wastewater sector. Within the reviewed indicators, most of them were focused on technological aspects of resource recovery processes such as nutrient removal efficiency, sewage sludge processing methods and environmental aspects as the pollutant share in the sewage sludge or its ashes. Moreover, other wide-scope indicators such as the wastewater service coverage or the production of bio-based fertilizers and hydrochar within the wastewater sector were analyzed. The results were used for the development of recommendations for improving the resources recovery monitoring framework in the wastewater sector and a proposal of a circularity indicator for a wastewater treatment plant highlighting new challenges for further researches and wastewater professionals.


Asunto(s)
Aguas Residuales , Purificación del Agua , Fertilizantes , Fósforo , Aguas del Alcantarillado , Eliminación de Residuos Líquidos
6.
Environ Sci Eur ; 33(1): 109, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34603904

RESUMEN

BACKGROUND: Climate change is a problem which is global in nature, and whose effects go across a wide range of disciplines. It is therefore important that this theme is taken into account as part of universities´ teaching and research programs. METHODS: A three-tiered approach was used, consisting of a bibliometric analysis, an online survey and a set of case studies, which allow a profile to be built, as to how a sample of universities from 45 countries handle climate change as part of their teaching programs. RESULTS: This paper reports on a study which aimed at identifying the extent to which matters related to climate change are addressed within the teaching and research practices at universities, with a focus on the training needs of teaching staff. It consists of a bibliometric analysis, combined with an online worldwide survey aimed at ascertaining the degree of involvement from universities in reducing their own carbon footprint, and the ways they offer training provisions on the topic. This is complemented by a set of 12 case studies from universities round the world, illustrating current trends on how universities handle climate change. Apart from reporting on the outcomes of the study, the paper highlights what some universities are doing to handle climate issues, and discusses the implications of the research. CONCLUSIONS: The paper lists some items via which universities may better educate and train their students on how to handle the many challenges posed by climate change. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12302-021-00552-5.

7.
Compr Rev Food Sci Food Saf ; 20(5): 5197-5225, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34337851

RESUMEN

Berries represent one of the most important and high-valued group of modern-day health-beneficial "superfoods" whose dietary consumption has been recognized to be beneficial for human health for a long time. In addition to being delicious, berries are rich in nutrients, vitamins, and several bioactive compounds, including carotenoids, flavonoids, phenolic acids, and hydrolysable tannins. However, due to their high value, berries and berry-based products are often subject to fraudulent adulteration, commonly for economical gain, but also unintentionally due to misidentification of species. Deliberate adulteration often comprises the substitution of high-value berries with lower value counterparts and mislabeling of product contents. As adulteration is deceptive toward customers and presents a risk for public health, food authentication through different methods is applied as a countermeasure. Although many authentication methods have been developed in terms of fast, sensitive, reliable, and low-cost analysis and have been applied in the authentication of a myriad of food products and species, their application on berries and berry-based products is still limited. The present review provides an overview of the development and application of analytical chemistry methods, such as isotope ratio analysis, liquid and gas chromatography, spectroscopy, as well as DNA-based methods and electronic sensors, for the authentication of berries and berry-based food products. We provide an overview of the earlier use and recent advances of these methods, as well as discuss the advances and drawbacks related to their application.


Asunto(s)
Flavonoides , Frutas , Dieta , Humanos
8.
Data Brief ; 36: 106994, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33889697

RESUMEN

The data presented in this article are related to the research paper "Granulation of fly ash and biochar with organic lake sediments - A way to sustainable utilization of waste from bioenergy production" [1] in the context of waste material investigation and possible valorization instead of disposal. This article provides a comprehensive chemical and physical characterization of wood combustion products - fly ashes, bottom ashes, mixed ashes and biochar. Multiple analytical techniques and methodology were exploited to investigate the composition of wood combustion products, among them a loss on ignition, potentiometry, colorimetry, X-ray diffractometry, X-ray fluorescence spectrometry, inductively coupled plasma optical emission spectrometry, gas chromatography. General parameters detected were the content of dry matter, gravimetric water, volatile matter, amount of ash and fixed carbon. The elemental analysis involved determining C, H, N and O. Physical properties were described by bulk density, solid density, total porosity, electric conductivity, specific weight and mass ratio assessment of particle size distribution. The mineralogical composition was described by major crystalline phases of samples and content of oxides. Chemical properties and composition were characterized by pH, the content of ammonium, nitrates, nitrites, exchangeable elements and cation exchange capacity as well as after the 3-step speciation and analytical quantification of trace and major elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sr, Ti, Tl, V and Zn) and detection of polycyclic aromatic hydrocarbons.

9.
Foods ; 10(3)2021 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-33803219

RESUMEN

Vaccinium genus berries-wild bilberries (Vaccinium myrtillus L.) and cultivated highbush blueberries (Vaccinium corymbosum L.)-are consumed worldwide, and their consumption has a trend of stable increase. Thus, considering their wide use in ethnomedicine, for juice and jam production, as functional food, as well as their use in preparations of extracts which have application potential in pharmaceutical and cosmetics industries, studies regarding the composition of these berries are of special importance. The aim of this study is to characterise the elemental and isotopic composition, as well as variation in element concentration in bilberries gathered from different sites in Northern Europe and in commercially available blueberry samples from across the World. Furthermore, our aim was to develop tools for authenticity and quality control of these berries. The elemental composition of berries was analysed using inductively coupled plasma with optical emission detection (ICP-OED), while isotope ratio mass spectrometry (IRMS) was used for the determination of isotope ratio values. The results demonstrated detectable differences between macro- and microelement values in bilberries. IRMS analysis of blueberries revealed significant differences in isotope ratios based on the place of origin, indicating the possibility to use this analytical method for authenticity testing. In none of the samples, pollution was detected, even though there were indications of different growth conditions and geochemical differences affecting bilberry composition.

10.
Food Chem ; 354: 129517, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-33756336

RESUMEN

In this study, cuticular wax load, its chemical composition, and biosynthesis, was studied during development of wild type (WT) bilberry fruit and its natural glossy type (GT) mutant. GT fruit cuticular wax load was comparable with WT fruits. In both, the proportion of triterpenoids decreased during fruit development concomitant with increasing proportions of total aliphatic compounds. In GT fruit, a higher proportion of triterpenoids in cuticular wax was accompanied by a lower proportion of fatty acids and ketones compared to WT fruit as well as lower density of crystalloid structures on berry surfaces. Our results suggest that the glossy phenotype could be caused by the absence of rod-like structures in GT fruit associated with reduction in proportions of ketones and fatty acids in the cuticular wax. Especially CER26-like, FAR2, CER3-like, LTP, MIXTA, and BAS genes showed fruit skin preferential expression patterns indicating their role in cuticular wax biosynthesis and secretion.


Asunto(s)
Antocianinas/química , Vaccinium myrtillus/química , Ceras/química , Ácidos Grasos/análisis , Ácidos Grasos/química , Frutas/química , Frutas/metabolismo , Microscopía Electroquímica de Rastreo , Extractos Vegetales , Vaccinium myrtillus/metabolismo , Vaccinium myrtillus/ultraestructura
11.
Chemosphere ; 263: 128105, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33297100

RESUMEN

Contamination associated with metals is a critical concern related to their toxicity, persistence, and bio-accumulation. Trace elements are partitioned into several chemical forms, which some are more labile during fluctuations in the environment. Studying the distribution of metals between the different chemical fractions contributes to assess their bioavailability and to identify their potential risk of contamination to surrounding environments. This study concerns the speciation of metals (Pb, Cr, Ni, Zn and Fe) from sediments coming out from Malmfjärden bay, Sweden. The aim was to assess the potential risk of metal pollution during present and future dredging as well as while using dredged sediments in beneficial uses. The Tessier speciation procedure was chosen, and the results showed that low concentrations of metals were associated with the exchangeable fraction. In contrast, the major concentrations were linked to the residual part. The risk indexes (contamination factor and risk assessment code) showed that, during dredging activities, there is a low concern of pollution for Cr, Ni and Fe and a medium risk for Pb and Zn. Additionally, in all elements, the sum of non-residual concentrations was below the Swedish limits for using dredged sediments in sensitive lands. The findings suggested that the investigated metals in Malmfjärden sediments are related to low risks of spreading during using in beneficial uses.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados/análisis , Medición de Riesgo , Suecia , Contaminantes Químicos del Agua/análisis
12.
Foods ; 9(5)2020 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-32380739

RESUMEN

The outer-most layer of plant surface, the cuticle, consists of epi- and intra-cuticular wax. It protects the plant from dehydration, extreme temperatures and UV radiation, as well as attacks from pests such as molds and bacteria. Berry cuticular waxes are studied to understand the metabolism character (factors affecting wax layer composition in different berry species) and increase the microbial resistance and shelf life of berries. The aim of this study was analysis of the surface wax composition of nine species of wild and cultivated berries from Northern Europe. Cuticular wax analysis were done using gas chromatography-mass spectrometry. A total of 59 different compounds were identified belonging to nine groups of compounds, namely, alkanes, phytosterols, alcohols, fatty acids, phenolic acids, ketones, aldehydes, esters and tocopherols. The analyzed blueberries had the highest amount of wax present on their surface (0.9 mg berry-1), triterpenoids were the main wax constituent in these berries, with up to 62% wax composition. Berry species and varieties were compared based on their surface wax composition-similarities were found between different blueberry varieties; however, other berries showed differences based on concentration and composition of cuticular wax.

13.
Environ Technol ; 41(1): 29-35, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30794045

RESUMEN

The development of pyro-gasification technologies makes necessary the development of new express analytical methods that are able to deal with the variability of feedstock and problems arising from it. Thermogravimetric proximate analysis of refuse derived fuels is a very fast, cheap and simple method for the determination of proximate and fractional composition. Development of this analytical approach may result in a very cost-effective method to describe wholesome composition and characteristics of feedstock used for pyrolysis and gasification processes in real time. The aim of this study was the development of such analytical method. Refuse derived fuel samples produced in Latvia and Estonia analysed during this study with thermogravimetric proximate analysis and standard methods. Equations for determination of gross calorific value and elemental composition from thermogravimetric proximate analysis were developed. Furthermore, results show that also signals pointing to excessive proportion of chlorine and fluorine can be obtained, using this method. The results obtained during this study can help to develop the automatic feedstock quality control systems for modern thermal processing technologies used in waste management.


Asunto(s)
Residuos de Alimentos , Eliminación de Residuos , Administración de Residuos
14.
Food Chem ; 295: 441-448, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31174780

RESUMEN

Aerial surfaces of plants are covered by a waxy cuticle protecting plants from excessive water loss and UV light. In the present study, composition and morphology of cuticular waxes of northern wild berry species bilberry (Vaccinium myrtillus L.), lingonberry (V. vitis-idaea L.), bog bilberry (V. uliginosum L.) and crowberry (Empetrum nigrum L.) were investigated. Scanning electron microscopy (SEM) revealed differences in epicuticular wax morphology, and gas chromatography-mass spectrometry (GC-MS) analysis confirmed variation in chemical composition of cuticular waxes between the berry species. The dominant compounds in bilberry and lingonberry cuticular waxes were triterpenoids, while fatty acids and alkanes were the dominant ones in bog bilberry and crowberry, respectively. Wax extracted by supercritical fluid extraction (SFE) from industrial press cakes of bilberry and lingonberry contained linoleic acid and γ-linolenic acid as the dominant compounds. Furthermore, in vitro sun protection factor (SPF) of berry waxes depicted good UV-B absorbing capacities.


Asunto(s)
Arándanos Azules (Planta)/química , Vaccinium myrtillus/química , Vaccinium vitis-Idaea/química , Ceras/análisis , Antocianinas , Fraccionamiento Químico/métodos , Ácidos Grasos/análisis , Finlandia , Frutas/química , Cromatografía de Gases y Espectrometría de Masas , Extractos Vegetales , Factor de Protección Solar , Rayos Ultravioleta , Ceras/química , Ceras/aislamiento & purificación
15.
Phytomedicine ; 53: 86-95, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30668416

RESUMEN

BACKGROUND: Anthocyanidins are plant phytochemicals found at high concentrations in berries, vegetables and flowers. Anthocyanidins have been extensively investigated due to their antioxidative, antidiabetic and anti-inflammatory effects. Few studies show that anthocyanidins decrease obesity and improve bone density. However, the effects of anthocyanidins on tissue regeneration have not been sufficiently clarified. Human mesenchymal stem cells (MSCs) are multipotent adult stem cells responsible for the regeneration of fat, bone and cartilage. Although MSCs are often used for screening of biologically active compounds, so far, the effect of anthocyanidins on MSC differentiation has not been addressed. PURPOSE: The aim of this study was to analyse the effect of anthocyanidins malvidin, cyanidin and delphinidin on adipose tissue-derived MSC differentiation into adipocytes, osteocytes and chondrocytes. STUDY DESIGN AND METHODS: Differentiation into adipocytes, osteocytes and chondrocytes was carried out in the defined cell culture conditions in the presence or absence of malvidin, cyanidin and delphinidin. The differentiation was confirmed by cytochemical staining and tissue-specific gene and protein expression. Antiobesity and anti-diabetes drug liraglutide was used as a reference drug in this study. RESULTS: Delphinidin inhibited MSC adipogenesis and downregulated FABP4 and adiponectin genes. Malvidin induced a significantly higher accumulation of calcium deposits in MSCs comparing to untreated MSCs, as well as upregulated the osteocyte-specific gene BMP-2 and Runx-2 expression and induced BMP-2 secretion. Cyanidin and delphinidin demonstrated a chondrogenesis stimulating effect by upregulation of Col2a1 and aggrecan. CONCLUSION: Altogether, our data show that anthocyanidins malvidin, cyanidin and delphinidin exert favourable effects on MSC osteogenesis and chondrogenesis whereas delphinidin inhibits adipogenesis. These results suggest that anthocyanidin effects on tissue regeneration could be further analysed in depth in vivo.


Asunto(s)
Antocianinas/farmacología , Diferenciación Celular/efectos de los fármacos , Células Madre Mesenquimatosas/efectos de los fármacos , Adipocitos/citología , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Adipocitos/fisiología , Adipogénesis/efectos de los fármacos , Tejido Adiposo/metabolismo , Agrecanos/genética , Agrecanos/metabolismo , Fármacos Antiobesidad/farmacología , Diferenciación Celular/fisiología , Células Cultivadas , Condrocitos/citología , Condrocitos/fisiología , Condrogénesis/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Células Madre Mesenquimatosas/citología , Osteocitos/citología , Osteocitos/fisiología , Osteogénesis/efectos de los fármacos
16.
Artículo en Inglés | MEDLINE | ID: mdl-30562630

RESUMEN

Although the wild parsnip (Pastinaca sativa L. s.l.) fruits are known to contain linear and angular furanocoumarins, the individual components of the seeds have not been fully identified and quantitated, and, in the case of immature seeds, reported. In view of this, the main furanocoumarin compounds were extracted using pyridine, and were isolated using semi-preparative high-performance liquid chromatography. The structural elucidation of isolated compounds was done based on detailed spectral analysis conducted by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI/MS), 1H and 13C NMR and, where possible, by gas chromatography-mass spectrometry (GC-MS). The quantitative analysis of furanocoumarin compounds in the wild parsnip was conducted by analytical ultra-performance liquid chromatography (UPLC-DAD), calculated against the standard curves of isolated compounds. The total yields of furanocoumarin compounds from the seeds after extraction with pyridine were 107.2-222.8 mg g-1 (fresh weight) and 50.2-66.4 mg g-1 (soluble dry matter). Thirteen furanocoumarins were identified. The main compounds (percentage in FW) in immature seeds were bergapten (40.8), pimpinellin (10.5), methoxsalen (5.7), isopimpinellin (4.3), imperatorin (3.2), and phellopterin (7.2). Seven constituents previously not described in P. sativa seeds and its products were identified, namely, byakangelicol (14.4), heraclenin (8.5), isobergapten (2.5), byakangelicin (1.3), heraclenol (0.5), psoralen (0.3), and isobyakangelicin (0.8). The latter is a new compound of the Apiaceae family. Extraction of immature seeds using pyridine gave a much higher yield and a greater variety of furanocoumarins. This indicates that the wild parsnip, along with other Apiaceae family plants, may be an important source of bioactive compounds.


Asunto(s)
Furocumarinas/análisis , Furocumarinas/química , Pastinaca/química , Semillas/química , Cromatografía Líquida de Alta Presión , Furocumarinas/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados , Espectrometría de Masa por Ionización de Electrospray
17.
Plants (Basel) ; 7(4)2018 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-30352980

RESUMEN

The amplified production of fruit as well as burgeoning demand for plant-made food products have resulted in a sharp increase of waste. Currently, millions of tons of by-products are either being discarded or utilized rather ineffectively. However, these by-products may be processed and further incorporated as functional ingredients in making high-value food products with many physiological and biochemical effects. The chemical analysis of pomace oils using gas chromatography-mass spectrometry (GC/MS) and reversed-phase-liquid chromatography coupled with fluorescence detector (RP-HPLC/FLD) systems led to the identification and quantification of 56 individual lipophilic compounds including unsaturated, polyunsaturated and saturated fatty acids, as well as phytosterols and four homologs of tocopherol. The oils recovered from by-products of Malus spp. (particularly cv. "Ola") are rich in fatty acids such as linolenic (57.8%), α-linolenic (54.3%), and oleic (25.5%). The concentration of total tocopherols varied among the Malus species and dessert apples investigated, representing the range of 16.8⁻30.9 mg mL-1. The highest content of total tocopherols was found in M. Bernu prieks, followed by M. cv. "Ola", and M. × Soulardii pomace oils. A significantly higher amount of δ-tocopherol was established in the oil of M. Bernu prieks, indicating that this species could be utilized as a natural and cheap source of bioactive molecules. ß-Sitosterol was the prevalent compound determined in all tested pomace oils with a percentage distribution of 10.3⁻94.5%. The main triterpene identified in the oils was lupeol, which varied in the range of 0.1⁻66.3%. A targeted utilization of apple pomace would facilitate management of tons of by-products and benefit the environment and industry.

18.
Water Sci Technol ; 78(12): 2481-2488, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30767913

RESUMEN

Water pollution due to industrial processes has necessitated and spurred robust research into the development of adsorbent materials for remediation. Polyphenylenediamines (PPD) have attracted significant attention because of their dual cationic and redox properties. They are able to reduce Cr(VI) to Cr(III) in solution. Interrogation of the chemical processes involved in the Cr(VI) adsorption on para-PPD was primarily by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) spectroscopy. It was confirmed that the underlying oxidation of the amino groups to imines during the reduction of Cr(VI) to Cr(III) was irreversible. This process occurred at both acidic and alkaline conditions. Reduction was accompanied by Cr(III) chelation on the adsorbent surface. Further, regeneration with dilute aqueous NaOH and HCl extended the polymer's adsorptive capacity beyond exhaustion of its redox potentials.


Asunto(s)
Cromo/química , Fenilendiaminas/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Cromo/análisis , Concentración de Iones de Hidrógeno , Fenilendiaminas/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/análisis
19.
J Hazard Mater ; 304: 553-6, 2016 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-26607871

RESUMEN

Thousands of articles have been devoted to examine different types of biosorbents and their use in cleaning polluted waters. An important objective of some studies has been the identification of the biosorption mechanisms. This type of investigation is not always performed, as it can only be done if scientists are aware of all mechanisms that, at least theoretically, control the removal of the target substances. Mistakes are often made, even in highly cited review articles, where biosorption mechanisms are named and/or grouped. The aim of this article is to highlight errors and inaccuracies as well as to discuss different classification systems of the biosorption mechanisms. This article serves as a guide, as well as a platform for discussion among researchers involved in the investigation of biosorbents, in an effort to avoid reproducing errors in subsequent articles.


Asunto(s)
Metales/química , Contaminantes Químicos del Agua/química , Adsorción , Comunicación , Proyectos de Investigación
20.
Water Sci Technol ; 68(10): 2208-13, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24292469

RESUMEN

The increasing industrial use of thallium has raised the need for removal of this highly toxic element from wastewater. Thallium is more toxic than cadmium, copper, zinc, lead and mercury and as it is easily accumulated in humans, animals and plants, it poses a threat to both the environment and human health. Peat has been used as an effective, relatively cheap and easily available sorbent to treat waters containing heavy metals. In this study, peat was characterized and used as sorbent for the removal of Tl(I) ions from aqueous solution. The effect of initial Tl(I) concentration, pH, contact time, temperature and ionic strength was studied in batch mode. The maximum sorption capacity of peat reached 24.14 mg/g at 20 °C and initial Tl(I) concentration of 500 mg/L. Sorption capacity was found to be pH dependent and maximum uptake occurred at pH 10. Kinetic data revealed that sorption was relatively rapid - 82.8% of Tl(I) ions were sorbed in the first 10 min. The kinetics of sorption was analyzed using pseudo-first order and pseudo-second order models. Results show that peat can be used as an effective sorbent to remove Tl(I) ions from aqueous solutions.


Asunto(s)
Suelo/química , Talio/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Modelos Químicos , Concentración Osmolar , Temperatura , Purificación del Agua
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