scholarly journals Enzymatic oxidation of phenolic compounds in coffee processing wastewater

2015 ◽  
Vol 73 (1) ◽  
pp. 39-50 ◽  
Author(s):  
Juliana Arriel Torres ◽  
Pricila Maria Batista Chagas ◽  
Maria Cristina Silva ◽  
Custódio Donizete dos Santos ◽  
Angelita Duarte Corrêa

Peroxidases can be used in the treatment of wastewater containing phenolic compounds. The effluent from the wet processing of coffee fruits contains high content of these pollutants and although some studies propose treatments for this wastewater, none targets specifically the removal of these recalcitrant compounds. This study evaluates the potential use of different peroxidase sources in the oxidation of caffeic acid and of total phenolic compounds in coffee processing wastewater (CPW). The identification and quantification of phenolic compounds in CPW was performed and caffeic acid was found to be the major phenolic compound. Some factors, such as reaction time, pH, amount of H2O2 and enzyme were evaluated, in order to determine the optimum conditions for the enzyme performance for maximum oxidation of caffeic acid. The turnip peroxidase (TPE) proved efficient in the removal of caffeic acid, reaching an oxidation of 51.05% in just 15 minutes of reaction. However, in the bioremediation of the CPW, the horseradish peroxidase (HRP) was more efficient with 32.70% ± 0.16 of oxidation, followed by TPE with 18.25% ± 0.11. The treatment proposed in this work has potential as a complementary technology, since the efficiency of the existing process is intimately conditioned to the presence of these pollutants.

2011 ◽  
Vol 78 (2) ◽  
pp. 97-103 ◽  
Author(s):  
Stanisław Weidner ◽  
Monika Karolak ◽  
Magdalena Karamać ◽  
Ryszard Amarowicz

Grapevine seedlings<em> Vitis vinifera</em> were grown in a greenhouse under optimum conditions (soil moisture ca 70%) and under drought stress (soil moisture ca 35%). In addition, some of the plants subjected to drought underwent subsequent regeneration under optimum conditions. Drought stress caused accumulation of total phenolic compounds in grapevine roots, which may indicate that these compounds play an important role in the adaptation of roots to growth under stress conditions. Phenolic acids found in the roots occurred in the ester-bound form only. p-coumaric acid was present in the highest concentrations (6.2 to 10.5 µg/g fresh matter). The content of ferulic acid was lower, ranging from 2.4 to 4.6 µg/g fresh matter. The lowest concentration in grapevine roots was achieved by caffeic acid (2.4 to 2.9 µg/g fresh matter). The levels of p-coumaric and ferulic acids in roots rose significantly under the drought stress, while the concentration of caffeic acid increased during the post-drought recovery period. This may suggest that some of the phenolic acids protect plants under stress conditions. All the extracts from grapevine roots had antioxidative properties, but the antiradical activity of the extracts obtained from roots subjected to drought stress was inferior to the control. The same extracts were also characterised by depressed reducing power. The results imply that tolerance of grapevine to soil drought may be associated with the value of antioxidative potential in root tissues of these plants.


2020 ◽  
Vol 3 (1) ◽  
pp. 47
Author(s):  
Nadezhda Petkova ◽  
Manol Ognyanov ◽  
Blaga Inyutin ◽  
Petar Zhelev ◽  
Panteley Denev

Crab apple (Malus baccata (L.) Borkh.) was mainly distributed in Europe as an ornamental plant, but the nutritional properties of its edible fruits were not fully revealed. The aim of the current study was to characterize the phytochemical composition of ripen carb apple fruits and to evaluate their nutritional and antioxidant potentials. The fruits were assayed for moisture and ash content, proteins, lipids, carbohydrates, titratable acidity (TA), pH, total phenolic compounds and natural pigments. Among the analyzed carbohydrates cellulose was found in the highest content (6% dw), followed by sugars (sucrose, glucose and fructose) and 1.8 % dw uronic acids. The total chlorophylls and carotenoids contents in their fruits were 6.51 and 4.80 μg/g fw, respectively. Total monomeric anthocyanins were not detected. The highest content of total phenolic compounds (2.67 mg GAE/g fw) was found in 95 % ethanol extract from fruits, while the total flavonoids were relatively low – 0.1 mg QE/g fw. DPPH assay (17.27 mM TE/g fw) and FRAP assay (14.34 mM TE/g fw) demonstrated in vitro antioxidant activities of crabapple. Malus baccata fruits were evaluated as a rich source of dietary fibers and phenolic compounds with significant antioxidant potential that could be used in human nutrition.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1810
Author(s):  
Monika Kędzierska-Matysek ◽  
Małgorzata Stryjecka ◽  
Anna Teter ◽  
Piotr Skałecki ◽  
Piotr Domaradzki ◽  
...  

The study compared the content of eight phenolic acids and four flavonoids and the antioxidant activity of six Polish varietal honeys. An attempt was also made to determine the correlations between the antioxidant parameters of the honeys and their polyphenol profile using principal component analysis. Total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (ABTS) and reduction capacity (FRAP) were determined spectrophotometrically, and the phenolic compounds were determined using high-performance liquid chromatography (HPLC). The buckwheat honeys showed the strongest antioxidant activity, most likely because they had the highest concentrations of total phenols, total flavonoids, p-hydroxybenzoic acid, caffeic acid, p-coumaric acid, vanillic acid and chrysin. The principal component analysis (PCA) of the data showed significant relationships between the botanic origin of the honey, the total content of phenolic compounds and flavonoids and the antioxidant activity of the six Polish varietal honeys. The strongest, significant correlations were shown for parameters of antioxidant activity and TPC, TFC, p-hydroxybenzoic acid, caffeic acid and p-coumaric acid. Analysis of four principal components (explaining 86.9% of the total variance), as a classification tool, confirmed the distinctiveness of the Polish honeys in terms of their antioxidant activity and content of phenolic compounds.


Antioxidants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 398
Author(s):  
Muneera D. F. AlKahtani ◽  
Yaser M. Hafez ◽  
Kotb Attia ◽  
Emadeldeen Rashwan ◽  
Latifa Al Husnain ◽  
...  

Drought stress deleteriously affects growth, development and productivity in plants. So, we examined the silicon effect (2 mmol) and proline (10 mmol) individually or the combination (Si + proline) in alleviating the harmful effect of drought on total phenolic compounds, reactive oxygen species (ROS), chlorophyll concentration and antioxidant enzymes as well as yield parameters of drought-stressed sugar beet plants during 2018/2019 and 2019/2020 seasons. Our findings indicated that the root diameter and length (cm), root and shoot fresh weights (g plant−1) as well as root and sugar yield significantly decreased in sugar beet plants under drought. Relative water content (RWC), nitrogen (N), phosphorus (P) and potassium (K) contents and chlorophyll (Chl) concentration considerably reduced in stressed sugar beet plants that compared with control in both seasons. Nonetheless, lipid peroxidation (MDA), electrolyte leakage (EL), hydrogen peroxide (H2O2) and superoxide (O2●−) considerably elevated as signals of drought. Drought-stressed sugar beet plants showed an increase in proline accumulation, total phenolic compounds and up-regulation of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD) activity to mitigate drought effects. Si and proline individually or the combination Si + proline considerably increased root and sugar yield, sucrose%, Chl concentration and RWC, MDA and EL were remarkably reduced. The treatments led to adjust proline and total phenolic compounds as well as CAT and SOD activity in stressed sugar beet plants. We concluded that application of Si + proline under drought stress led to improve the resistance of sugar beet by regulating of proline, antioxidant enzymes, phenolic compounds and improving RWC, Chl concentration and Nitrogen, Phosphorus and Potassium (NPK) contents as well as yield parameters.


2021 ◽  
pp. 1-10
Author(s):  
Leandro Marcolino Vieira ◽  
Renata de Almeida Maggioni ◽  
Jéssica de Cássia Tomasi ◽  
Erik Nunes Gomes ◽  
Ivar Wendling ◽  
...  

Abstract Ilex paraguariensis, commonly known as yerba mate, is a tree species native to South America. Its commercial value is due to the manufacturing of teas, with potential also in the pharmacological and cosmetic industries. Vegetative propagation of yerba mate is considered an innovation to the traditional production systems based on sexual propagation. The present study aimed to evaluate the rhizogenic potential and chemical attributes of mini-cuttings from 15 yerba mate genotypes, as well as to verify the correlation between phytochemical and rooting-related variables. Mini-cuttings were collected from a pre-existing mini-clonal hedge and the experimental design was completely randomized, with 15 treatments (genotypes), four replications and 10 mini-cuttings per plot. After 120 days, mini-cuttings were assessed regarding rooting, mortality, callogenesis and leaf retention percentages, percentage of mini-cuttings with both calluses and roots, number of roots and average root length. At the time of collection, subsamples from each plot were used for phytochemical analyses including total phenolic compounds, protein, caffeine and theobromine contents and antioxidant activity. Rooting percentages ranged from 5 to 72.5%, with significant variation among genotypes. Adventitious rooting and phytochemical profile of yerba mate mini-cuttings are genotype-dependent. Leaf retention is a relevant factor in the rooting of yerba mate mini-cuttings and the levels of total phenolic compounds, antioxidants and theobromine present in mini-cuttings are negatively correlated components to Ilex paraguariensis adventitious rooting.


Fermentation ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 137
Author(s):  
Luis F. Castro ◽  
Abigail D. Affonso ◽  
Renata M. Lehman

Specialty malts are commonly used in brewing to provide flavor, aroma, and color to wort and beer. The use of specialty malts contributes to the variety of beer products; therefore, it is important to understand their effect on the characteristics of wort and beer. This study investigates the impact of various specialty malts on wort and beer properties. A control beer was prepared with 100% base malt, and four beer treatments were prepared with the addition of kilned, roasted, and caramel specialty malts. For each treatment, 20% of the base malt was substituted with the various specialty malts when preparing the wort. The fermentable sugars and free amino nitrogen (FAN) content for each wort were analyzed. Alcohol by volume (ABV), international bitterness units (IBU), diacetyl, and polyphenol content of each prepared beers were subsequently analyzed. Results showed that wort prepared with the addition of roasted and caramel malts contained a lower concentration of fermentable sugars and FAN than wort prepared with the base and kilned malts. Beers prepared with the addition of roasted and caramel malts exhibited the lowest levels of ABV, as well as the lowest levels of diacetyl. These beers also exhibited higher levels of total phenolic compounds compared to the other beer samples. No change was observed in IBU levels as a result of brewing with the different specialty malts. This study illustrates how the use of specialty malts impacts wort and beer properties, providing useful information to aid in the production of quality beer products.


Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 46
Author(s):  
Mariana de Oliveira Silva ◽  
John Nonvignon Bossis Honfoga ◽  
Lorena Lucena de Medeiros ◽  
Marta Suely Madruga ◽  
Taliana Kênia Alencar Bezerra

Coffee husks (Coffea arabica L.) are characterized by exhibiting secondary metabolites such as phenolic compounds, which can be used as raw material for obtaining bioactive compounds of interest in food. The objective of this study is to evaluate different methods for obtaining the raw material and extracting solutions of bioactive compounds from coffee husks. Water bath and ultrasound-assisted extraction methods were used, using water (100%) or ethanol (100%) or a mixture of both (1:1) as extracting solutions and the form of the raw material was in natura and dehydrated. The extracts were evaluated by their antioxidant potential using DPPH radicals, ABTS, and iron reduction (ferric reducing antioxidant power (FRAP)), and later total phenolic compounds, total flavonoids, and condensed tannins were quantified the phenolic majority compounds were identified. It was verified that the mixture of water and ethanol (1:1) showed better extraction capacity of the compounds with antioxidant activity and that both conventional (water bath) or unconventional (ultrasound) methods showed satisfactory results. Finally, a satisfactory amount of bioactive compounds was observed in evaluating the chemical composition (total phenolic compounds, total flavonoids, condensed tannins, as well as the analysis of the phenolic profile) of these extracts. Corroborating with the results of the antioxidant activities, the best extracting solution was generally the water and ethanol mixture (1:1) using a dehydrated husk and water bath as the best method, presenting higher levels of the bioactive compounds in question, with an emphasis on chlorogenic acid. Thus, it can be concluded that the use of coffee husk as raw material to obtain extracts of bioactive compounds is promising. Last, the conventional method (water bath) and the water and ethanol mixture (1:1) stood out among the methods and extracting solutions used for the dehydrated coffee husk.


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