Degradation Of Polyphenols Research Articles

Emerging natural and high-phenolic sweet substances: A review

Emerging high-phenolic sweeteners impart a sweet taste to foods and beverages, and are desirable sugar alternatives. Most refined sugars have a low antioxidant content due to polyphenol degradation occurring during sugar refining. Natural sweeteners such as honey, molasses, and dark brown sugar possess moderate to high phenolic content. Other phytochemicals found in natural sweeteners are carotenoids, organic acids, and terpenoids. Additionally, molasses and syrups synthesised from anthocyanin-rich fruits and roots contain anthocyanins apart from flavonoids. Non-nutritive sweeteners, such as sugar alcohols, are low in calories besides their sweet taste. Sweet proteins, dihydrochalcones, phenolics, and terpenoid derivatives are emerging sweeteners. These sweet substances are effective antioxidants that could help reduce oxidative stress in the human body although the amount ingested is usually low. The present review emphasised specific natural, high-phenolic, and other sweet compounds, and examined the antioxidative characteristics of these sweeteners. The risk of excessive ingestion of these sweet substances is yet to be proven.

The effects of mulberry polyphenols on the digestibility and absorption properties of pork myofibrillar protein in vitro

The objective of the present study was to explore the effect of mulberry polyphenols on the digestibility and absorption properties of myofibrillar protein (MP) in vitro. MP was extracted from the Longissimus et thoracis muscle of 18 different pig carcasses and the MP-mulberry polyphenols complex was prepared. The antioxidant activity of digestive juice, degradation of both MP and polyphenols, and the metabolism of MP and the MP-polyphenols complex by intestinal microbial activity during digestion and fermentation in vitro were compared. The results showed that mulberry polyphenols significantly affect the digestibility of MP and the antioxidant activity of digestive juices during digestion (P < 0.05). After the modification of the polyphenols, the hydrolysis of MP increased from 55.4% to 64.0%, and the molecular weight of protein digestion product significantly decreased (P < 0.05). The scavenging rates of 2, 2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl in the final digestive juice were 350.1 μmol Trolox/mg protein and 34.0%, respectively, which were 0.34 and 0.47-fold higher than those of the control (P < 0.05). Furthermore, the release and degradation of phenolic compounds mainly occurred during intestinal digestion, and polyphenols that reached the colon after digestion, through the fermentation of intestinal microorganisms in vitro, enriched Lactobacillus and promoted the production of short-chain fatty acids which has obvious potential to improve intestinal health.

Application of mathematical techniques to study the moisture loss kinetics and polyphenol degradation kinetics of mango (Mangifera indica L.) slices during heat pump drying by pilot equipment

In this study, mathematical technique was applied to evaluate the moisture loss and polyphenol compound degradation during the heat pump drying of mango slices. The experiment was carried out in two steps. First, the samples were dried at 20, 30, 40 and 50 °C; the data was subsequently inserted into the regression equations to evaluate the kinetics of the process. The results showed that selected Weibull model was the most suitable for describing mango slices' moisture loss during the drying process with the highest R2; the lowest χ2 and constant drying rate (k) varied from 7.91 to 4.07 min−1 in the temperature range of 20–50 °C. In addition, the Deff coefficients and the activation energy required for the moisture loss process were also calculated. During the drying process, polyphenols were considered an indicator of the quality of dried mango slices. The degradation of polyphenols was described according to first-order kinetics with R2 peaking at 0.9662. The nature of the drying, general methods for modeling the drying mechanism, and optimization of the processes were also discussed, providing insight into the overall drying process in terms of quantity and quality.

Comparative analysis of β-glucosidase activity in non-conventional yeasts.

The objective of this study was to evaluate the β-glucosidase activity in the non-conventional yeasts under cellulose, glucose and sucrose substrates. The participation of the enzyme β-glucosidase and its contribution to the enzymatic degradation of tannins is known. Within the classification of tannins are ellagitannins, molecules of gallic acid and ellagic acid, which are considered as nutraceutical compounds due to the properties that they present and that they can be used in the design of food and new drugs, synthesis of materials with antimicrobial capacity. The extracellular β-glucosidase activity was mainly presented in the Candida and Pichia strains, being the glucose and sucrose media the most capable for inducing the activity that showed maximum values with P. pastoris in glucose (0.1682±0.00 µmol/min mg protein), and C. utilis in cellulose (0.1129±0.1349 µmol/min mg of protein), and sucrose (0.0657±0.0214 µmol/min mg protein). Additionally, I. terricola and P. kluyvery stood out in a qualitative cellulose degradation approach measured by Congo red method (9.60±0.04 mm and 9.20±0.05 mm respectively). These indicate that P. pastoris and C. utilis have potential as β-glucosidase producers, especially when growing under complex carbon sources for biomass conversion, new biofuels production and polyphenol degradation with more manageable bioreactor process.

Treatment of High-Polyphenol-Content Waters Using Biotechnological Approaches: The Latest Update.

Polyphenols and their intermediate metabolites are natural compounds that are spread worldwide. Polyphenols are antioxidant agents beneficial for human health, but exposure to some of these compounds can be harmful to humans and the environment. A number of industries produce and discharge polyphenols in water effluents. These emissions pose serious environmental issues, causing the pollution of surface or groundwater (which are used to provide drinking water) or harming wildlife in the receiving ecosystems. The treatment of high-polyphenol-content waters is mandatory for many industries. Nowadays, biotechnological approaches are gaining relevance for their low footprint, high efficiency, low cost, and versatility in pollutant removal. Biotreatments exploit the diversity of microbial metabolisms in relation to the different characteristics of the polluted water, modifying the design and the operational conditions of the technologies. Microbial metabolic features have been used for full or partial polyphenol degradation since several decades ago. Nowadays, the comprehensive use of biotreatments combined with physical-chemical treatments has enhanced the removal rates to provide safe and high-quality effluents. In this review, the evolution of the biotechnological processes for treating high-polyphenol-content water is described. A particular emphasis is given to providing a general concept, indicating which bioprocess might be adopted considering the water composition and the economic/environmental requirements. The use of effective technologies for environmental phenol removal could help in reducing/avoiding the detrimental effects of these chemicals. In addition, some of them could be employed for the recovery of beneficial ones.

Extrusion-blown starch/PBAT biodegradable active films incorporated with high retentions of tea polyphenols and the release kinetics into food simulants

To reduce thermal degradation of tea polyphenols (TP) in final active packaging materials, poly(butylene adipate-co-terephthalate) (PBAT), starch, plasticizer, and TP were directly synthesized into masterbatches by one-pot method in this study without pre-dispersion, and then blown into active films. TP interacted with starch through hydrogen bonds, with little interaction with PBAT. Barrier properties were improved by incorporating TP into the films, whereas mechanical properties slightly decreased. Blending starch into PBAT greatly accelerated the degradation of the film. And the incorporation of TP slowed down the short-term degradation of the starch/PBAT film, but accelerated the long-term degradation. The initial total polyphenol content in the active film was positively related to the TP loading, whereas the initial retention rate remained above 95 % regardless of TP loadings. The retention rate of TP in active films decreased with storage time, but it was still above 80 % after 12 months, with a favorable stability. TP-loaded films displayed efficient antioxidant and antimicrobial activities with strong dose dependence. The release of TP into food simulants was mainly induced by random diffusion, with little effect from polymer swelling. The short-term release kinetics was well described by Fick's second law. This work has demonstrated the feasibility of TP being incorporated into the active films with high retention through high-throughput fabrication, which provides formula and technical options for the industrial development of active packaging materials.

Kinetic Model of Moisture Loss and Polyphenol Degradation during Heat Pump Drying of Soursop Fruit (Annona muricata L.)

The aim of this study is to investigate the impact of time and temperature of the heat pump drying process of soursop slices at different levels on moisture content and total polyphenol content (TPC). Twelve types of classical kinetic models have been used in this work to describe the suitability of experimental data with models. The conformity is assessed based on statistical values (e.g., coefficient of determination (R2), Chi–square value (X2), etc.). The loss of moisture in the material is described in accordance with Fick’s diffusion law. Value of moisture rate (MR), and effective moisture diffusivities (Deff) have been identified. Experimental results show that MR value depends on the time and drying temperature, Deff increases when increasing the drying temperature from 20–50 °C with values of 1.24 × 10−9, 1.85 × 10−8, 7.69 × 10−8, and 5.54 × 10−7 m/s2. The Singh et al. model is the best option to describe the moisture of the sliced soursop drying process at 30 °C (R2 = 0.97815). The largest TPC decomposition occurs at a temperature of 50 °C. The ability to decompose TPC is proportional to the drying temperature. The TPC decomposition dynamic model follows a first–order reaction when drying at 20 °C with a determinant coefficient R2 = 0.9693.

Micronization enhanced extractability of polyphenols and anthocyanins in tart cherry puree

Tart cherries (Prunus cerasus L.) are the richest in phenolic compounds, among all the members of drupe family of fruits. To reduce the inherent sourness of the cherries, thermal processing or filtration steps are used. These processes lead to changes in pH, and exposure to temperature enhances oxidation leading to degradation of polyphenols. In the present study, Megatron® and high-pressure homogenization (HPH) were employed to produce micronized puree, which was analyzed for polyphenolic, flavonoid and anthocyanin contents using various assays. Both methods of micronization lead to breakage of cell wall structure facilitating enhanced release of bioactives from the cellular matrix and thus higher antioxidant release. The presence of functional groups was corroborated by FTIR spectrophotometric analysis, and reversed phase HPLC for the presence and relative amounts of various polyphenols and anthocyanins. There was a significant increase (p<0.05) of in the extractability of polyphenols with HPH (285.05 GAE μg/g) in comparison with the non-micronized samples (166.80 GAE μg/g). The changes in anthocyanins and flavonoids were also significant (p<0.05), thus confirming the impact of micronization on the antioxidant release in tart cherries.

Hydrothermal treatment improves xanthine oxidase inhibitory activity and affects the polyphenol profile of Flos Sophorae Immaturus.

Flos Sophorae Immaturus (FSI) is rich in polyphenols and a potential uric acid-lowering food. However, the processing of FSI is greatly restricted due to the heat sensitivity and low solubility of polyphenols. In this study, hydrothermal treatment - an effective strategy - was applied to FSI processing. The variation of xanthine oxidase (XO) inhibitory effect and polyphenol composition of FSI during hydrothermal treatment were recorded. The XO inhibition rate of FSI increased from 32.42% to 89.00% after hydrothermal treatment at 220 °C for 30 min, as well as total polyphenols (from 0.66 to 1.11 mg mL-1 ) and flavonoids (from 1.21 to 1.58 mg mL-1 ). However, high thermal temperature (>160 °C) and extended thermal time (>90 min) caused the degradation of polyphenols. Rutin, kaempferol-3-O-rutinoside and narcissoside rapidly degraded and converted to quercetin, kaempferol and isorhamnetin when the temperature exceeded 160 °C. The maximum yields of quercetin, kaempferol and isorhamnetin were at 220 °C for 30 min, 90 min and 90 min, respectively. Meanwhile, the conversion kinetics conformed to the first-order model. Interestingly, these newly formed polyphenols possessed better XO inhibitory effects than their derivatives with 3-O-rutinoside. Polyphenol conversion during hydrothermal treatment was the main reason for enhancing XO inhibitory activity. Therefore, hydrothermal treatment is an appropriate method for improving the XO inhibitory effect of FSI. © 2022 Society of Chemical Industry.

Stability of bioactive components in smoothies within an extended period of one year

The aim of the study was the colourimetric determination of polyphenols and antioxidative capacity in blueberry- and cranberry smoothies monthly over one year with high-throughput methods, i.e., total polyphenols (PPm) and total antioxidant capacity (TAC). The main interest was directed to the smoothie storability in terms of light and temperature effects to prevent the consumption of antioxidants and the degradation of polyphenols. In this respect, smoothies from the same batch were stored under four conditions, i.e., room temperature (22 °C ± 2 °C) and light, fridge temperature (4 ± 2 °C) and light, room temperature (22 °C ± 2 °C) in the dark (glass bottles encased with tin foil) and fridge temperature (4 ± 2 °C) in the dark. Results showed a significant temperature-dependent effect in favour of fridge temperature (4 ± 2 °C) compared to room temperature (22 °C ± 2 °C). Thus, optimal storage conditions for the shelf life of blueberry- and cranberry smoothies were observed at fridge temperature (4 ± 2 °C). At the same time, the exclusion of light had a minor impact in the case of antioxidants. Regarding polyphenols, the low temperature was also a key factor preventing degradation in contrast to dimming, which did not provide additional benefit. Health-promoting bioactive phytochemicals and antioxidants might be well preserved in smoothies for almost an entire year, superior at fridge temperature (4 ± 2 °C) and exclusion of light.

Recent advances on the stability of dietary polyphenols

Recent advances on the stability of dietary polyphenols

Structure dependent stability and antioxidant capacity of strawberry polyphenols in the presence of canola protein

Polyphenol stability in processed food affects sensorial and health-promoting properties. Thus, understanding the effects of various food components on polyphenols degradation, as a function of their chemical structure, can contribute to optimal product engineering. The current study focuses on the impact of polyphenol structure on polyphenol-protein interactions in correlation with their stability and total antioxidant capacity (TAC) during shelf-life. A strawberry polyphenol extract (SPE) and canola protein extract (CPE) were used as multicomponent polyphenol and plant-based protein models. A non-covalent interaction of SPE and CPE was observed at pH = 3. Among CPE proteins cruciferin was the most involved in interactions, and the polyphenols with the highest relative binding were flavonols (45 ± 3%–68 ± 2%), while anthocyanins presented lower values (0 ± 0.4%–27 ± 1%). The presence of the proteins enhanced mostly the anthocyanins’ stability, yet the extent of the impact was not correlated with the relative binding. TAC was not better preserved by the presence of CPE.

Sensory and Physicochemical Characteristics of Two Common Roast Defects in Robusta Coffee

Roasting is an important coffee processing step to generate coffee aroma and flavor. Because roasting is time-temperature dependent, the variation of time and temperature applied may influence the structural properties, visual appearance, and chemistry of coffee. Improper roasting creates roast defects that reduce coffee quality and acceptance. Despite this importance, studies on coffee roast defects, particularly in Robusta coffee is limited. This study aims to characterize two common roast defects, i.e., underdeveloped and overdeveloped, compared with medium roast in Robusta coffee. Sensory evaluation by trained panelists and physicochemical evaluation reveal that the two common roast defect in Robusta coffee can be distinguished clearly through differences in sensory (aroma defect) characteristics as well as physicochemical properties. The overdeveloped roast defect produced darker coffee with the highest pH and total dissolve solids (TDS), and can be characterized by pyridine, furan, phenol and pyrrole derivatives. The carbony and ashy notes of the overdeveloped coffee were potentially contributed by phenol and polyphenol derivatives. In contrast to the overdeveloped coffee, the underdeveloped coffee is markedly characterized by higher concentration of aliphatic acids and higher concentration of pyrazines that contributes to raw nut-like notes. The combination of time and temperature during roasting influences the breakdown of chemical compounds through complex mechanisms involving proteins, carbohydrates and polyphenols degradation. Thus, roasting process variations that determine coffee cup quality and in turn drive consumer acceptance should be controlled.

Microbial Community Succession and Organic Pollutants Removal During Olive Mill Waste Sludge and Green Waste Co-composting.

Olive mill wastewater sludge (OMWS) is the main by-product of the olive industry. OMWS is usually dumped in landfills without prior treatment and may cause several eco-environmental hazards due to its high toxicity, which is mainly attributed to polyphenols and lipids. OMWS is rich in valuable biocompounds, which makes it highly desirable for valorization by composting. However, there is a need to understand how microbial communities evolve during OMWS composting with respect to physicochemical changes and the dynamics of pollutant degradation. In this study, we addressed the relationship between microbial community, physicochemical variations and pollutants degradation during the co-composting of OMWS and green wastes using metagenomic- and culture-dependent approaches. The results showed that in raw OMWS, Pichia was the most represented genus with almost 53% of the total identified fungal population. Moreover, the bacteria that dominated were Zymobacter palmae (20%) and Pseudomonas sp. (19%). The addition of green waste to OMWS improved the actinobacterial diversity of the mixture and enhanced the degradation of lipids (81.3%) and polyphenols (84.54%). Correlation analysis revealed that Actinobacteria and fungi (Candida sp., Galactomyces sp., and Pichia manshurica) were the microorganisms that had the greatest influence on the composting process. Overall, these findings provide for the first time some novel insights into the microbial dynamics during OMWS composting and may contribute to the development of tailored inoculum for process optimization.

Effect of Temperatures on Polyphenols during Extraction

Background: Polyphenols are a set of bioactive compounds commonly found in plants. These compounds are of great interest, as they have shown high antioxidant power and are correlated to many health benefits. Hence, traditional methods of extraction such as solvent extraction, Soxhlet extraction and novel extraction technologies such as ultrasound-assisted extraction and subcritical water extraction (SWE) have been investigated for the extraction of polyphenols. Scope and Approach: Generally, for traditional extractions, the total phenolic content (TPC) is highest at an extraction temperature of 60–80 °C. For this reason, polyphenols are regularly regarded as heat-labile compounds. However, in many studies that investigated the optimal temperature for subcritical water extraction (SWE), temperatures as high as 100–200 °C have been reported. These SWE extractions showed extremely high yields and antioxidant capacities at these temperatures. This paper aimed to examine the relevant literature to identify and understand the mechanisms behind this discrepancy. Results: Thermal degradation is the most common explanation for the degradation of polyphenols. This may be the case for specific or sub-groups of phenolic acids. The different extraction temperatures may have also impacted the types of polyphenols extracted. At high extraction temperatures, the formation of new compounds known as Maillard reaction products may also influence the extracted polyphenols. The selection of source material for extraction, i.e., the plant matrix, and the effect of extraction conditions, i.e., oxidation and light exposure, are also discussed. The overestimation of total phenolic content by the Folin–Ciocâlteu assay is also discussed. There is also a lack of consensus in TPC’s correlation to antioxidant activity.

Thermal Stability and Inhibitory Action of Red Grape Skin Phytochemicals against Enzymes Associated with Metabolic Syndrome

The present study focuses on heat-induced structural changes and the degradation kinetics of phytochemicals and antioxidant activity of red grape skin extract. The thermal degradation of anthocyanins, flavonoids, polyphenols, and antioxidant activity followed a first-order kinetic model, increasing with temperature due to the intensification of the degradation process. The activation energy (Ea) highlighted this phenomenon. Likewise, the kinetic and thermodynamic parameters certified the irreversible degradation of the bioactive compounds from the skin of the Băbească neagră grape variety. Both temperature and duration of heating had a significant impact on the content of bioactive compounds. In addition, the red grape skin extract inhibited certain enzymes such as α-amylase, α-glucosidase, lipase, and lipoxygenase, which are associated with metabolic syndrome and inflammation. Further knowledge on the possible inhibition mechanisms exerted by the major anthocyanins found in red grape skin extract on the metabolic syndrome-associated enzymes was gathered upon running molecular docking tests. Detailed analysis of the resulting molecular models revealed that malvidin 3-O-glucoside binds in the vicinity of the catalytic site of α-amylase and lipase, whereas no direct contact with catalytic amino acids was identified in the case of α-glucosidase and lipoxygenase.

Photocatalytic Degradation of Polyphenols and Polyaromatic Amines in Textile Industry Wastewaters by Nano-Cerium Dioxide Doped Titanium Dioxide and the Evaluation of Acute Toxicity Assays with Microtox and Daphnia magna

In this study, nano-cerium dioxide doped titanium-dioxide (CeO2 -TiO2 ) Nanocomposites (NCs) was used for the photocatalytic degradation of pollutant parameters (color, polyphenols, polyaromatics) from a textile industry wastewater (TI ww) treatment plant located in Izmir, Turkey, at different operational conditions such as at increasing photocatalytic time (0, 10, 15, 20, 30, 60, 90 and 120 min), at different CeO2 -TiO2 mass ratios (1%, 3%, 5%, 10%, 15%, 16%, 25%, 30%, 50%), at the different amounts of CeO2 (1, 3, 5, 8, 10, 15, 20 and 25 mg/L) under 130 W Ultraviolet (UV) and 35 W sun lights irradiations, respectively. Color, polyphenols (quercetin, fi setin, ellargic acid, carminic acid, luteolin, and curcumin) and polyaromatics [2,6-dimethylaniline (2,6-DMA), 2-aminoanisole (MOA), 2,4-toluenediamine (TDA), 2-naphthylamine (NA), 4,40-thiobisbenzenamine (TOA), 3,3-dichlorobenzidine (DCB) and 3,30-dimethoxybenzidine (DMOB)] removal effi ciencies were observed between 78% and 99% during photocatalytic experiments, under ¬130 W UV light, at 15% CeO2 -TiO2 NCs, at 21° C, after 30 min irradiation time. 15% CeO2 -TiO2 NCs shows the highest photodegradation yield of color under both UV and visible-light irradiation, with maximum photodegradation rates of 99% and 98.5%, respectively, after 30 min irradiation time. 94.44% maximum Microtox acute toxicity yield was found in CeO2 -TiO2 NCs = 20 mg/L, at 5% CeO2 mass ratio, after 150 min photodegradation time at 60o C. 90% maximum Daphnia magna acute toxicity removal was obtained in CeO2 -TiO2 NCs = 20 mg/L, at 5% CeO2 mass ratio, after 150 min photodegradation time at 60° C. The results show that the CeO2 -TiO2 NCs has a high photocatalytic activity to remove the pollutants from TI ww.

Stability of polyphenols in food processing.

In recent years, polyphenols have attracted considerable attention due to their diverse potential health-beneficial effects on humans. Polyphenols are widely distributed in natural plants, and therefore play an important role in human food. Thermal processing, irradiation, fermentation, high pressure, microwave, and drying are several popular food processing methods. However, polyphenols are instable in food processing, which easily degrade and react with other components because of their polyhydroxy characteristic. Traditional and advanced technologies have been used to characterize the stability of polyphenols. The main influence factors of stability of polyphenols such as pH, temperature, light, oxygen, enzymes, metal ions, as well as macromolecules, are summarized. Besides, thermal processing greatly promoted the degradation of polyphenols. Thermal degradation mechanisms and products of some polyphenols, such as quercetin and rutin, have been intensively demonstrated. Nevertheless, the structural changes of polyphenols caused by food processing, may lead to different bioactivities from the obtained results based on unprocessed polyphenols. Therefore, to maximize the beneficial effects of polyphenols ingested by human from processed food, the stability of polyphenols in food processing must be thoroughly investigated to assess their real bioactivities. In addition, some available technologies for improving the stability of polyphenols in food processing have been proposed.

Revealing microbial species diversity using sequence capture by hybridization.

Targeting small parts of the 16S rDNA phylogenetic marker by metabarcoding reveals microorganisms of interest but cannot achieve a taxonomic resolution at the species level, precluding further precise characterizations. To identify species behind operational taxonomic units (OTUs) of interest, even in the rare biosphere, we developed an innovative strategy using gene capture by hybridization. From three OTU sequences detected upon polyphenol supplementation and belonging to the rare biosphere of the human gut microbiota, we revealed 59 nearly full-length 16S rRNA genes, highlighting high bacterial diversity hidden behind OTUs while evidencing novel taxa. Inside each OTU, revealed 16S rDNA sequences could be highly distant from each other with similarities down to 85 %. We identified one new family belonging to the order Clostridiales , 39 new genera and 52 novel species. Related bacteria potentially involved in polyphenol degradation have also been identified through genome mining and our results suggest that the human gut microbiota could be much more diverse than previously thought.

Bacterial Degradation of Bacteriostatic Polyphenols, Tannins

Tannin degradation by bacteria has not been studied much as tannins are commonly known to be bacteriostatic due to enzyme inhibition, substrate deprivation, and the enzyme activity on the bacterial cell wall. However, about a handful of bacteria have been found to tolerate certain concentrations of tannin. This study focuses on isolating and identifying bacteria from decaying portions of tree bark for tannase production and effective catalysis of ester bond hydrolysis in tannins. Different concentrations of commercial tannic acid were used as the sole carbon source on mineral salt medium (MSM) agar plates, to test the maximum tolerable concentrations (MTCs) by the isolates. Tannin degradation was confirmed by a visual reading method and bacterial tannase activity and the biodegradation percentage were determined. One particular isolate was identified to have 50 g/L MTC of tannin, with a tannase activity of 51.61 U/mL that is optimum after 96 hours of incubation. The 16s rRNA sequencing results showed that the isolate belonged to Bacillus genus and the resulting bacterial strain isolate was found to be a new strain of Bacillus subtilis which was submitted to GenBank under the accession number MH330408.