Source Of Phenolic Compounds Research Articles

Insights into the 3D In Vitro Permeability and In Vivo Antioxidant Protective Effects of Kiwiberry Leaf Extract: A Step Forward to Human Nutraceutical Use.

Actinidia arguta (Siebold & Zucc.) Planch. ex Miq. (kiwiberry) leaves are a source of phenolic compounds with pro-health biological effects, such as antioxidant and anti-inflammatory activities. Despite the huge number of studies reporting the composition of A. arguta leaves, no in vitro or in vivo studies explore its potential use as nutraceutical ingredient based on these activities. Therefore, this study aims to characterize the safety profile of kiwiberry leaf extracts using in vitro and in vivo approaches through the assessment of intestinal cell viability (Caco-2 and HT29-MTX), 3D intestinal permeation, and, most important, the redox markers, biochemical profile and liver and kidney function effects after the animal assays. Briefly, wistar rats were orally treated for 7 days with kiwiberry leaf extracts (50 and 75 mg/kg bw), water (negative control), or vitamin C (positive control). The cell viability was above 90% at 1000 μg/mL for both cells. Coumaroyl quinic acid and rutin achieved a permeation higher than 25% in the 3D intestinal model. The animal studies confirmed the extracts' ability to increase superoxide dismutase, glutathione peroxidase, and catalase content in animals' livers and kidneys while simultaneously decreasing the triglycerides content. This study highlighted the antioxidant capacity of kiwiberry leaf extracts, ensuring their efficacy and safety as a nutraceutical ingredient.

Biotechnological Potential of Different Organs of Mistletoe (Viscum album L.) Collected from Various Host Tree Species in an Urban Area

From an economic and ecological standpoint, it is crucial to investigate the biologically active compounds of mistletoe plants, which are currently discarded by pruning urban mistletoe-infested trees. In the present study, the content of phenolic compounds, triterpenic and organic acids, as well as the antioxidant activity of the extracts of various mistletoe organs (leaves, stems, and fruits) collected from the most infested tree species were investigated. The mistletoe samples collected from Betula pendula, Acer platanoides, Crataegus monogyna, and Sorbus aucuparia showed the highest content of phenolic acids and flavonoids as well as antioxidant activity, as measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and ferric reducing/antioxidant power (FRAP) assays. The leaves and stems of mistletoe from Tilia cordata were characterized by a high content of triterpenic acids (oleanolic, ursolic, and betulinic). The leaves and fruits of mistletoe plants from Populus nigra and Salix alba contained a high concentration of organic acids, particularly succinic and citric acids. Compared to stem and leaf extracts, the antioxidant activity of the mistletoe fruit extracts was 1.5–3 times higher. The obtained results indicate that mistletoe is a valuable raw material and can be used as a source of phenolic compounds and triterpenic and organic acids, as well as for producing extracts with antioxidant properties.

Modulation of gut microbiota and their metabolites by functional mulberry juice non-thermally pasteurized using microfiltration

Background: Mulberry fruit is a source of phenolic compounds and has biological properties. This study aimed to assess the effects of isomaltooligosaccharide (IMO) added to mulberry juice on prebiotic activity and gut fermentation properties.Objectives: The study aimed to produce mulberry juice supplemented with IMO, which might generate short chain fatty acids (SCFA), and to examine the effects of a prebiotic activity after fecal fermentation.Materials and methods: Functional mulberry juices were prepared with three different levels of isomaltooligosaccharide (IMO), namely 0% (MBI0), 2% (MBI2), and 8% (MBI8). The study tested mulberry juices supplemented with IMO, which generated short-chain fatty acids (SCFA), phenolic metabolites, and favored beneficial gut bacteria, and examined the prebiotic activity after fecal fermentation by the colonic microbiota. A crossflow hollow fiber microfiltration system with a 0.22 μm pore size was employed to deliver permeates considered non-thermally pasteurized juices.Results: The results show that short chain fatty acids (SCFA) included large propionic acid and butyric acid concentrations at 48h. The percent of bifidobacteria significantly increased to 5.03% and 17.53% in 24 hours fermentation of MBI2 and MBI8, respectively. After fecal batch culture fermentation, some anthocyanin metabolites such as 3-(2-hydroxyphenyl) propionic acid, 3,4-dihydroxybenzaldehyde, L-phenylalanine, and aminocaproic acid, were detected. Therefore, IMO can serve as a potential prebiotic ingredient added in mulberry juice for promoting the growth of beneficial gut microbiota.Conclusion: The results show that IMO favored beneficial microorganisms in the gut and contributed to biologically active compounds such as metabolites of polyphenols and anthocyanins in the gut.Keywords: Mulberry, isomaltooligosaccharide, prebiotic, gut microbiota, metabolites

Comparative study on the phenolic composition and in vitro bioactivity of medicinal and aromatic plants from the Lamiaceae family

Medicinal and aromatic plants (MAP) have been described as a source of phenolic compounds with potential as antioxidant, antiproliferative and antimicrobial agents. MAP from the Lamiaceae family (Origanum vulgare L., Thymus vulgaris L., Ocimum basilicum L., Salvia officinalis L., Melissa officinalis L., and MatricariachamomillaL.) were selected to perform a phytochemical and biological screening for their further exploitation as natural bioactive ingredients. The total content of phenolic compounds varied from 184.02 mg/g extract in M. officinalis to 17.97 mg/g extract in M. chamomilla. Caffeic and rosmarinic acids were the main phenolic acids found in the respective hydroalcoholic extracts. The extracts showed a promising antioxidant activity in vitro, being related the phenolic compositions of the extracts, furthermore, all extracts being able to combat lipid peroxidation in TBARS assays with an IC50 under 26 μg/mL, moreover all the plant extract has prevented the oxidative haemolysis in OxHLIA assays at concentrations below 67 μg/mL in a Δt 60 min and under 118 μg/mL for a Δt 120 min. Regarding to the bactericidal and fungicidal action the plant extracts were able to inhibit growth against bacteria associated with food hazards, such as Salmonella typhimurium (MIC < 1) and Listeria monocytogenes (MIC < 1), regarding to fungicidal activity it can be highlighted the MIC values under to 0.25 for Aspergillus versicolor and Trichoderma viride. Overall, the selected Lamiaceae plants stood out as a source of active phytochemicals that can be used by different industries, such as food and cosmetics.

Pomegranate (Punica granatum L.) Peel Extracts as Antimicrobial and Antioxidant Additives Used in Alfalfa Sprouts.

Aqueous and ethanolic pomegranate peel extracts (PPE) were studied as a source of phenolic compounds with antimicrobial, anti-quorum sensing, and antioxidant properties. The aqueous extract showed higher total phenolic and flavonoid content (153.43 mg GAE/g and 45.74, respectively) and antioxidant capacity (DPPH radical inhibition: 86.12%, ABTS radical scavenging capacity: 958.21 mg TE/dw) compared to the ethanolic extract. The main phenolic compounds identified by UPLC-DAD were chlorogenic and gallic acids. The aqueous PPE extract showed antimicrobial activity against Listeria monocytogenes, Salmonella Typhimurium, Candida tropicalis (MICs 19–30 mg/mL), and anti-quorum sensing activity expressed as inhibition of Chromobacterium violaceum violacein production (%). The aqueous PPE extracts at 25 mg/mL applied on alfalfa sprouts reduced psychrophilic bacteria (1.12 Log CFU/100 g) and total coliforms (1.23 Log CFU/100 g) and increased the antioxidant capacity of the treated sprouts (55.13 µmol TE/100 g (DPPH) and 126.56 µmol TE/100 g (ABTS)) compared to untreated alfalfa. This study emphasizes PPE’s antioxidant and antimicrobial activities in alfalfa sprouts preservation.

Wine residues extracts modulating in vitro metabolic syndrome

Metabolic syndrome is considered a worldwide epidemic health problem. The manifestations include obesity, dyslipidemias, elevation of arterial blood pressure, and insulin resistance. The wine waste is composed mainly of skin, seed and grape pomace, and is a source of phenolic compounds. Previous studies have demonstrated that grape phenolic compounds have antioxidants and anti-inflammatory properties, acting directly in the pathogenic process of several diseases. In order to improve the bioavailability and bioactivity of these compounds, enzymatic biotransformation reactions were developed.The aimed of this work was to evaluate whether phenolic extracts produced with wine waste by biotransformation with Tannase (tannin acyl hydrolase), were able to attenuate the metabolic syndrome manifestations like oxidative stress and reduce the inflammatory parameters in vitro assays.Four different extracts were produced and the non-citotoxic concentrations of samples used (100, 200 and 500 μg/mL) were determined by MTT assay. The inflammatory response was induced in macrophages (RAW 264.7) culture using LPS (Lipopolysaccharide). The biotransformed extracts were able to reduce the TNF-α cell culture supernatant concentration by about 44%; and the IL-6 secretion was reduced by 82%. All the extracts demonstrate efficacy in reduction of intracellular reactive oxygen species (ROS) production and the same was observed for NO (nitric oxide) concentration in the cell culture supernatant after the administration of extracts. These results indicated the strong potential of employing phenolic wine waste extracts on the modulation of metabolic syndrome parameters, use that also brings environmental and socioeconomic advantages, since it brings an alternative for the use of residues.

Phenolic Profile and Antioxidant, Anticholinergic, and Antibacterial Properties of Corn Tassel.

Corn tassel (CT) is a waste part of the corn plant. It is a good co-product and rich in terms of bioactive compounds and phytochemicals. This research tried to show the phenolic profile, antioxidants, anticholinergic activities, and antibacterial properties of CT ethanol extract. The phenolic content analysis of the CT was determined quantitatively by LC-MS/MS, and the antioxidant capacity was measured using ABTS, DPPH, Cu2+–Cu+, and Fe3+–Fe2+ reducing methods. The anticholinergic measurements of CT were detected by inhibition of acetylcholinesterase (AChE). The antibacterial activity was determined by MIC and disc diffusion methods. Many phenolic compounds such as vanillic acid, caffeic acid, fumaric acid, acetohydroxamic acid, butein, myricetin, resveratrol, catechin hydrate, and 4-hydroxybenzoic acid were detected in ethanol extract of CT. The obtained plant ethanol extract had a 7.04% DPPH value, while it showed ABTS activity at 9.45%. Moreover, it had a 0.10 mg/mL inhibition effect on the AChE in terms of IC50 values. The ethanol extract of the CT had an antibacterial property on the investigated bacteria at different ratios. In conclusion, this research aims to consider CT as a source of phenolic compounds and to reveal its bioactive properties and its effects on the treatment of some diseases.

Winemaking by-products as a source of phenolic compounds: Comparative study of dehydration processes

The circular bioeconomy for the production of high-value products has gained attention due to new policies for the reuse and sustainable valorisation of locally available underutilised raw material in several countries. This study is focused to explore the potential of the by-products of winemaking through direct dehydration processes. The phenolic composition (anthocyanins and uncolored phenols) and their quantitative pattern in the skin, seeds and stems were determined by ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC-QqQ-MS/MS). The results showed that lyophilisation and mainly the Spiral Flash dryer, as the most feasible system for industrial application, could be a promising process for producing high added-value ingredients with retention of bioactive phenolic compounds. The skin fraction is a rich source of anthocyanins. In a complementary way, the seeds are an important source of hydroxybenzoic acids, procyanidins and lignans, a family of phenolic compounds little studied in grapes and wine. Regardless of the dehydration method, the stems are an important source of a wide range of phenolic compounds, mainly proanthocyanidins. The present study established that the winemaking process provides an excellent source of raw materials for the recovery of ingredients rich in valuable phenolic compounds, thus contributing to the circular bioeconomy.

Pomegranate Peels and Seeds as a Source of Phenolic Compounds: Effect of Cultivar, By-Product, and Extraction Solvent.

The nutraceutical properties of Punica granatum L. are not restricted to the edible portion of the fruit but also to the peels and seeds, flowers, leaves, and tree bark. The recovery and valorization of the peel and seeds (ca. 50% of the whole fruit), besides the positive environmental impact, can be viewed as a source of natural bioactive compounds. Thus, the bioactive properties of extracts of pomegranate peel and seeds from Acco and Wonderful known cultivars, as well as of the novel Big Full cultivar, were evaluated. The dried and ground pomegranate by-products were submitted to a conventional solid/liquid extraction with ethanol/water mixtures (0%, 25%, 50%, and 75% of EtOH, v/v). The obtained extracts were characterized in terms of total phenolic compounds (TPC), total flavonoids (TF), and antioxidant activity (AA), determined by the DPPH radical scavenging activity and expressed as IC50 (half maximum inhibitory concentration). With the exception of the Acco cultivar, the extraction yield (EY) was higher for peels, whose extracts showed higher TPC, TF, and IC50 (lower AA). The extracts obtained from the by-products of the Big Full cultivar had a statistically higher overall bioactive potential (TPC: 0.36 mg GAE/mg extract; TF: 0.031 mg CATE/mg extract; IC50: 0.51 mg/mL) compared to the other two studied cultivars. Furthermore, the EY was enhanced by solvents richer in ethanol (50-75%), allowing obtaining extracts richer in TPC and TF with higher AA. Finally, it was shown that EY combined with bioactive data allowed a satisfactory principal component unsupervised differentiation of the pomegranate extracts according to the type of by-product used.

Obtaining green extracts rich in phenolic compounds from underexploited food by-products using natural deep eutectic solvents. Opportunities and challenges

Phenolic compounds have attracted scientific interest due to their bioactive properties. Moreover, the environmental awareness has increased considerably and, with it, research into valorisation processes. Food waste is a source of bioactive compounds, however, the most common methods of extracting these compounds were polluting. Recently, the use of natural deep eutectic solvents (NADES) is being studied as a way to achieve a green extraction process. This article reviews the opportunities offered by some underexploited food by-products (potato peels, grape pomace, beetroot and olive leaves) as sources of phenolic compounds and discusses the possible application of NADES for extraction. The literature reviewed concludes that these by-products are a rich source of polyphenols and that natural solvents are a real alternative for their extraction. However, further research is needed to overcome the drawbacks of NADES, as well as to study the feasibility of the application of the extracts in the food industry.

Salpianthus macrodontus Extracts, a Novel Source of Phenolic Compounds with Antibacterial Activity against Potentially Pathogenic Bacteria Isolated from White Shrimp.

This study aimed to evaluate the antibacterial activity in vitro of Salpianthus macrodontus and Azadirachta indica extracts against potentially pathogenic bacteria for Pacific white shrimp. Furthermore, the extracts with higher inhibitory activity were analyzed to identify compounds responsible for bacterial inhibition and evaluate their effect on motility and biofilm formation. S. macrodontus and A. indica extracts were prepared using methanol, acetone, and hexane by ultrasound. The minimum inhibitory concentration (MIC) of the extracts was determined against Vibrio parahaemolyticus, V. harveyi, Photobacterium damselae and P. leiognathi. The polyphenol profile of those extracts showing the highest bacterial inhibition were determined. Besides, the bacterial swimming and swarming motility and biofilm formation were determined. The highest inhibitory activity against the four pathogens was found with the acetonic extract of S. macrodontus leaf (MIC of 50 mg/mL for Vibrio spp. and 25 mg/mL for Photobacterium spp.) and the methanol extract of S. macrodontus flower (MIC of 50 mg/mL for all pathogens tested). Both extracts affected the swarming and swimming motility and the biofilm formation of the tested bacteria. The main phenolic compounds related to Vibrio bacteria inhibition were naringin, vanillic acid, and rosmarinic acid, whilst hesperidin, kaempferol pentosyl-rutinoside, and rhamnetin were related to Photobacterium bacteria inhibition.

Valorization of Spent Sugarcane Fermentation Broth as a Source of Phenolic Compounds

A methodology based on a solid phase extraction (SPE) was optimized for the recovery of phenolic compounds from the spent fermentation broth generated from Biofene® (trans-β-farnesene) production. For this purpose, two resins (XAD-2 and HP-20) and three desorption solutions (water, 50/50 ethanol/water, and ethanol) were tested. The most efficient resin revealed to be the HP-20, using ethanol as desorption solution, reaching an overall total phenolic compound recovery of ca. 80% when 6 BV (bed volume) of both feed and ethanol were applied. The optimization of the resin’s process cycle pointed to 15 BV feed to be treated per cycle and using the same volume of ethanol in the desorption step, with no need for an extra resin regeneration step, stably yielding 48% total phenolic compound recovery from the spent broth for at least 4 cycles, translating into 60 BV of feed being treated per BV of resin, and with the resin being still perfectly active. The extract was characterized using LC−ESI−UHR−QqTOF−MS, and a total of 82 and 15 compounds were identified, in negative and positive ionization modes, respectively. Organic acids were the main class of compounds identified in the phenolic-rich extract, followed by phenolic compounds, saccharides, peptides or amino acids and vitamins. Additionally, the extract revealed a significant antioxidant capacity (914.1 ± 51.6 and 2764.5 ± 142.8 µmol Trolox equivalents/g-dw, respectively, with ABTS and ORAC methodologies), which might be interesting for a wide variety of applications.

Grape and Grape-Based Product Polyphenols: A Systematic Review of Health Properties, Bioavailability, and Gut Microbiota Interactions

Grapevine-derived products have been widely studied for their reported benefits, especially those related to the prevention of cardiovascular diseases. However, in recent years, the interest in the study of grapes and their non-fermented derivatives (grape juices) has gained prominence over the well-known interest in red wine, since grapes and grape juices seem to be widely related to the beneficial effects associated with the Mediterranean diet, and consequently to the presence of phenolic compounds. The focus of this systematic review was the phenolic profiles of grape, juice, and wine, as well as the possible beneficial effects of their consumption on the human microbiota through a systematic literature review. PubMed and Scopus were accessed during April 2021 and the PRISMA methodological protocol was followed. To the best of our knowledge, this is the first time that the PRISMA methodology has been applied to this systematic knowledge. This methodology allowed for a scientific description of: (a) the comparison between grapes and their derived products as source of phenolic compounds, (b) great possibilities for working on a new line of investigation based on the synergy between polyphenol consumption and microbiota, and (c) the urgent need for strategies to improve the bioavailability of these compounds.

Inhibitory potential of phenolic compounds of Thai colored rice (Oryza sativa L.) against α-glucosidase and α-amylase through in vitro and in silico studies.

This study investigated the inhibitory efficiency of phenolic compounds content methyl vanillate, syringic acid and vanillic acid against α-glucosidase and α-amylase. The phenolic compound contents of 10 Thai colored rice cultivars were also determined, and the relationship between the inhibitory efficiency of colored rice extract with methyl vanillate, syringic acid and vanillic acid was evaluated. The results revealed that the inhibition efficiency of methyl vanillate, syringic acid and vanillic acid was higher against α-glucosidase than against α-amylase. Inhibitory activity of vanillic acid against α-glucosidase and α-amylase was highest, with IC50 of 0.100 ± 0.01 and 0.130 ± 0.02 mmol L-1 , respectively. Docking study showed strong binding by three hydrogen bonds and four hydrogen bonds between vanillic acid with the amino acid in the binding site of α-glucosidase and α-amylase, respectively. Inhibition modes of these phenolic compounds were defined as a mixed type inhibition against α-glucosidase. Highest phenolic compound contents of methyl vanillate, syringic acid and vanillic acid were obtained from methanol extracts of all rice cultivars. The methanol extracts of all colored rice cultivars such as Khao Leum Pua also showed the highest inhibition potential against α-glucosidase and α-amylase. The results indicated that these phenolic compound contents were closely related to the inhibition potential of colored rice extracts against α-glucosidase and α-amylase. Our results suggest that rice, especially colored rice cultivars, has the source of phenolic compounds. Moreover, the phenolic compounds had the greatest source of natural inhibitor against α-glucosidase and α-amylase. © 2022 Society of Chemical Industry.

Development and Box-Behnken design optimization of a green extraction method natural deep eutectic solvent-based for phenolic compounds from barley malt rootlets.

In recent years, attention has been turned finding new sources of phenolic compounds, antioxidant molecules, main by-products from the agri-food chain like barley malt rootlets (BMRs). Traditionally, phenolic compounds are extracted from food matrices using different procedures, for example, solid-liquid, liquid-liquid, or solid-phase extraction techniques employing organic solvents. With the advent of green chemistry, attention has been paid to the search for green, nontoxic, inexpensive, and nonflammable solvents and the natural deep eutectic solvents (NADESs) respect these characteristics. The aim of this project was to develop and optimize an environmentally friendly, inexpensive, and rapid extraction method for phenolic compounds from BMRs using natural DESs as extractive solvents. Several natural DESs were tested as extractive solvents and, among them, the best results in terms of total phenolic content were obtained using a choline chloride-malic acid (1:2 molar ratio)-based mixture. Box-Behnken experimental design guaranteed the extraction of 9.51 ± 0.83 gallic acid equivalent/g of BMRs, under the following optimal extraction conditions: 1:21 solid-to-liquid ratio, 80°C as extraction temperature, 43min as the time of extraction, and 29% as a percentage of added water in the NADESs. Phenolic acids and flavonoids were detected in the BMRs extract through HPLC-PDA/MS analysis.

HPLC-DAD assay of phenols profile in Antennaria dioica (L.) Gaertn

Antennaria dioica (Asteraceae family) – is a perennial herb, commonly found in dry grasslands and sandy or stony places from Eurasian areas. It is known in traditional medicine as antioxidant, diuretic, choleretic and anti-inflammatory remedy. This species should be reconsidered as possible sources of phenols, mainly flavonoids and hydroxycinnamic acids. Thus, the aim of this study was to validate a chromatographic method for detection of phenols and their identification in A. dioica herb. HPLC-DAD method was evaluated in terms of linearity, precision, repeatability, accuracy, LOD and LOQ. The calibration curves of thirteen reference substances were linear (R2 &amp;gt; 0.99) over the range of 5–400 µg/mL, the LODs and the LOQs were in the range of 0.1–0.3 µg/mL and 0.2–1.0 µg/mL, respectively. During HPLC-DAD assay two flavones – luteolin, apigenin; flavonol – quercetin and three its glycosides – rutin, hyperoside and isoquercitrin; coumarins: coumarin and umbelliferone; five hydroxycinnamic acids – chlorogenic, caffeic, p-coumaric, trans-ferulic and rosmarinic were identified in A. dioica herb. This phytochemical study of A. dioica confirms that this plant material is a rich source of phenolic compounds.

Polyphenolic extract from Punica granatum peel causes cytoskeleton-related damage on Giardia lamblia trophozoites in vitro.

BackgroundDiarrheal diseases caused by protozoa have a great impact on human health around the world. Giardia lamblia is one of the most common flagellates in the intestinal tract. Factors such as adverse effects to first-line drugs or the appearance of drug-resistant strains, make it necessary to identify new treatment alternatives. Agroindustry waste, like pomegranate peel, are a source of phenolic compounds, which possess antiparasitic activities. In vivo studies demonstrated antigiardiasic potential by reducing cyst shedding and protecting intestinal cells; however, they did not identify the compounds or elucidate any mechanism of action in the parasite. The objective of this study is to identify potential molecular targets and to test the in vitro effects of polyphenols from Punica granatum on Giardia lamblia.MethodsThe in vitro antigiardial potential of polyphenolic extract from pomegranate peel (Punica granatum L.) obtained using microwave-ultrasound methodology was evaluated on Giardia lamblia trophozoites. Extract phytochemical identification was performed by HPLC/MS analysis. The effect of polyphenolic extract on growth and adhesion capacity was determined by parasite kinetics; morphological damage was evaluated by SEM, alteration on α-tubulin expression and distribution were analyzed by western blot and immunofluorescence, respectively.ResultsThe pomegranate peel extract showed the presence of ellagitannins (punicalin and punicalagin, galloyl-dihexahydroxydiphenoyl-hexoside), flavones (luteolin), and ellagic acid, that caused an inhibitory effect on growth and adhesion capacity, particularly on cells treated with 200 µg/mL, where growth inhibition of 74.36%, trophozoite adherence inhibition of 46.8% and IC50 of 179 µg/mL at 48 h were demonstrated. The most important findings were that the extract alters α-tubulin expression and distribution in Giardia trophozoites in a concentration-independent manner. Also, an increase in α-tubulin expression at 200 µg/mL was observed in western blot and diffuse or incomplete immunolabeling pattern, especially in ventral disk. In addition, the extract caused elongation, disturbance of normal shape, irregularities in the membrane, and flagella abnormalities.DiscussionThe pomegranate peel extract affects Giardia trophozoites in vitro. The damage is related to the cytoskeleton, due to expression and distribution alterations in α-tubulin, particularly in the ventral disk, a primordial structure for adhesion and pathogenesis. Microtubule impairment could explain morphological changes, and inhibition of adhesion capacity and growth. Besides, this is the first report that suggests that ellagic acid, punicalin, punicalagin and luteolin could be interactioning with the rich-tubulin cytoskeleton of Giardia. Further investigations are needed in order to elucidate the mechanisms of action of the isolated compounds and propose a potential drug alternative for the giardiasis treatment.

Tea Infusions as a Source of Phenolic Compounds in the Human Diet

Phenolic compounds are components with proven beneficial effects on the human body, primarily due to their antioxidant activity. In view of the high consumption of tea and the numerous factors that affect the nutritional value of its infusions, the aim of this study was to identify the effects of tea type and duration of leaf extraction with water on the levels of phenolic compounds and other components that determine biological activity (oxalates, Ca, Na, Cu, and Mn). Based on assays, infusions of red tea prepared for 20 min were found to be the best source of phenolics (202.9 mg/100 mL), whereas the lowest level of these compounds was determined in infusions of black tea extracted from leaves for 30 min (46.9 mg/100 mL). The highest degree of increase in polyphenol content (by approx. 50%) was noted in red and green tea infused for between 10 and 20 min, whereas for black tea, polyphenol levels decreased with time. The biological activity of tea infusions appears to be determined to the greatest extent by the interactions between phenolic compounds and oxalates (r = 0.6209), calcium (r = 0.8516), and sodium (0.8045). A daily intake of three to four mugs (1 L) of tea infusions provides the human body the entire amount of phenolics recommended for health reasons (as regards red tea, this is possible at 1/3 of the volume) and covers the daily requirement for manganese, as well as (partially) copper.

Current Options in the Valorisation of Vine Pruning Residue for the Production of Biofuels, Biopolymers, Antioxidants, and Bio-Composites following the Concept of Biorefinery: A Review.

Europe is considered the largest producer of wine worldwide, showing a high market potential. Several wastes are generated at the different stages of the wine production process, namely, vine pruning, stalks, and grape marc. Typically, these residues are not used and are commonly discarded. Portugal generates annually approximately 178 thousand metric tons of wine production waste. In this context, the interest in redirecting the use of these residues has increased due to overproduction, great availability, and low costs. The utilization of these lignocellulosic biomasses derived from the wine industry would economically benefit the producers, while mitigating impacts on the environment. These by-products can be submitted to pre-treatments (physical, chemical, and biological) for the separation of different compounds with high industrial interest, reducing the waste of agro-industrial activities and increasing industrial profitability. Particularly, vine-pruning residue, besides being a source of sugar, has high nutritional value and may serve as a source of phenolic compounds. These compounds can be obtained by bioconversion, following a concept of biorefinery. In this framework, the current routes of the valorisation of the pruning residues will be addressed and put into a circular economy context.

Physical and chemical characterization of Corchorus olitorius leaves dried by different drying techniques

Molokhia, Corchorus olitorius, is a popular leafy vegetable, known in many world regions as a good source of nutritional and medicinal properties. Due to its short shelf life and the limited harvesting time, processing such as drying techniques permit to preserve and provide it throughout the year. In the present study, it was attempted to reveal the main physical and chemical characteristics of molokhia leaves. Also, three drying techniques, shade drying (SHD), convective drying (COD), and microwave drying (MID), have been applied to study the kinetics and their main physical and chemical effects. The analysis demonstrated that molokhia leaves are a good source of phenolic compounds, flavonoids, and chlorophylls pigments. Those bioactive compounds have provided the leaves with considerable antiradical scavenging and reducing capacities. Drying time decreased from days, in the case of SHD, to some hours when using COD, and less than 20 min when using MID. Increasing drying temperature and power input have increased the drying rate. Modelling of drying kinetics of MID three power inputs (350, 500 and 750 W) and COD at 60 °C exhibited a high fitting for most empirical models (R2 > 0.980). SHD was less deleterious on leaves colour. Also, it preserved the content of phenolics, flavonoids, and thus the antioxidant activity of leaves. On the contrary, COD at 80 °C had a detrimental effect on previous components and their activity. Vega-Gálvez model can be presented as the best-fitted model to describe the rehydration kinetics of dried leaves. Rheological analysis of the aqueous extracts of the leaves demonstrated the effect of time and grinding on the increase of mucilage diffusion. The obtained results could help industrials to choose the convenient drying method and more analysis on the subject are recommended.