The Profile and Content of Polyphenolic Compounds and Antioxidant and Anti-Glycation Properties of Root Extracts of Selected Medicinal Herbs.

The objective of our study was to analyse the extracts from six medicinal herb roots (marshmallow, dandelion, liquorice, angelica, burdock, and comfrey) in terms of antioxidant capacity (ABTS, DPPH) and inhibition of advanced glycation end product (AGEs) formation. The quantification of phenolic acids and flavonoids was analysed using the UHPLC-DAD-MS method. Fifteen polyphenolic compounds were detected in the studied herbs. The higher number of polyphenols were found in marshmallows (ten polyphenols), while the lowest was in comfrey (five compounds). Liquorice root revealed the highest individual phenolic concentration (382 µg/g dm) with the higher contribution of kaempferol-3-O-rutinoside. Comfrey root extract was characterised by the most abundant TPC (Total Phenolic Content) value (29.79 mg GAE/ g dm). Burdock and comfrey showed the strongest anti-AGE activity studies with the BDA-GLU model. Burdock root was also characterised by the highest anti-AGE activity in the BSA-MGO model. The highest antioxidant capacity was determined by ABTS (72.12 µmol TE/g dw) and DPPH (143.01 µmol TE/g dw) assays for comfrey extract. The p-coumaric acid content was significantly correlated with anti-AGE activity determined by the BSA-MGO model. This research sheds new light on the bioactivity of root herbs, explaining the role of p-coumaric acid in preventing diabetes.

Quality and functional properties of bread containing the addition of probiotically fermented Cicer arietinum.

This study aimed to determine the impact of supplementation with probiotically fermented chickpea (Cicer arietinum L) seeds on the quality parameters and functional characteristics of wheat bread. The addition of chickpea seeds caused significant changes in the chemical composition of the control wheat bread. The legume-supplemented products exhibited higher values of a* and b* color parameters and higher hardness after 24 h of storage than the control. The application of fermented or unfermented chickpeas contributed to an increase in total polyphenol and flavonoid contents, iron chelating capacity, and antioxidant properties of the final product. The variant containing unfermented seeds had the highest riboflavin content (29.53 ± 1.11 µg/100 g d.w.), Trolox equivalent antioxidant capacity (227.02 ± 7.29 µmol·L-1 TX/100 g d.w.), and free radical scavenging activity (71.37 ± 1.30 % DPPH inhibition). The results of this preliminary research have practical importance in the production of innovative bakery products with potential properties of functional food.

Evaluation of Environmental Factor Effects on the Polyphenol and Flavonoid Content in the Leaves of Chrysanthemum indicum L. and Its Habitat Suitability Prediction Mapping.

The leaves of Chrysanthemum indicum L. are known to have various bioactive compounds; however, industrial use is extremely limited. To overcome this situation by producing high-quality leaves with high bioactive content, this study examined the environmental factors affecting the phytochemical content and antioxidant activity using C. indicum leaves collected from 22 sites in Kochi Prefecture, Japan. Total phenolic and flavonoid content in the dry leaves ranged between 15.0 and 64.1 (mg gallic acid g-1) and 2.3 and 11.4 (mg quercetin g-1), while the antioxidant activity (EC50) of the 50% ethanol extracts ranged between 28.0 and 123.2 (µg mL-1) in 1,1-Diphenyl-2-picrylhydrazyl radical scavenging assay. Among the identified compounds, chlorogenic acid and 1,5-dicaffeoylquinic acid were the main constituents in C. indicum leaves. The antioxidant activity demonstrated a positive correlation with 1,5-dicaffeoylquinic acid (R2 = 0.62) and 3,5-dicaffeoylquinic acid (R2 = 0.77). The content of chlorogenic acid and dicaffeoylquinic acid isomers varied significantly according to the effects of exchangeable magnesium, cation exchange capacity, annual temperature, and precipitation, based on analysis of variance. The habitat suitability map using the geographical information system and the MaxEnt model predicted very high and high regions, comprising 3.2% and 10.1% of the total area, respectively. These findings could be used in future cultivation to produce high-quality leaves of C. indicum.

A novel hybrid sensor array based on the polyphenol oxidase and its nanozymes combined with the machine learning based dual output model to identify tea polyphenols and Chinese teas.

A novel sensor array was developed based on the enzyme/nanozyme hybridization for the identification of tea polyphenols (TPs) and Chinese teas. The enzyme/nanozyme with polyphenol oxidase activity can catalyze the reaction between TPs and 4-aminoantipyrine (4-AAP) to produce differences in color, and the sensor array was thus constructed to accurately identify TPs mixed in different species, concentrations, or ratios. In addition, a machine learning based dual output model was further used to effectively predict the classes and concentrations of unknown samples. Therefore, the qualitative and quantitative detection of TPs can be realized continuously and quickly. Furthermore, the sensor array combining the machine learning based dual output model was also utilized for the identification of Chinese teas. The method can distinguish the six teas series in China, and then precisely differentiate the more specific tea varieties. This study provides an efficient and facile strategy for the identification of teas and tea products.

Antioxidant, Anti-Diabetic, and Anti-Inflammation Activity of Garcinia livingstonei Aqueous Leaf Extract: A Preliminary Study.

Diabetes mellitus (DM) is the second leading cause of mortality globally. The increased concern for DM is due to the underlying complications accompanying hyperglycaemia, associated with oxidative stress and consequent inflammation. The investigation of safe and effective treatments for DM is necessary. In the present study, the cytotoxicity, phytochemical analysis, antioxidant capacity, anti-inflammatory, and antidiabetic effects in an aqueous extract of Garcinia livingstonei leaves were assessed. All tested extract concentrations showed no toxicity against C3A hepatocytes. Several phenolic compounds were identified using ultra-high performance liquid chromatography mass spectrometry (UHPLC-MS). The total polyphenol content was 100.9741 mg GAE/g, 16.7712 mg CE/g flavanols, and 2.3548 mg QE/g flavonols. The antioxidant capacity values were 253.4268 mg AAE/g, 192.232 mg TE/g, and 167.8724 mg TE/g for ferric reducing antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC), and 2,2-diphenyl-1-pycrylhydrazyl (DPPH), respectively. The plant extract significantly (p < 0.05) demonstrated anti-inflammatory and hypoglycaemic effects in a dose-dependent manner, with the α-glucosidase inhibition of the extract being higher (p < 0.05) than in the standard conventional drug (acarbose). The findings of this study revealed the potential of the constituents of G. livingstonei aqueous leaf extract in DM treatment. Further studies on the preparation and mechanisms of action of the plant in DM treatment are recommended.

Pharmacognostical studies of Eclipta prostrata (Linn. ) grown in Sri Lanka / Estudios farmacognósticos de Eclipta prostrate (Linn. ) cultivada en Sri Lanka

Eclipta prostrata Linn. is an annual herbaceous plant used in traditional medicine, commonly known as "Trailing Eclipta" or False Daisy in English, ' Keekirindiya ' in Sinhala and ' Kayyantakara' in Tamil. The aim of this study was to conduct a detailed pharmacognostical evaluation of E. prostrata found in Sri Lanka. Anatomical, physicochemical, phytochemical studies, and quantification of phyto - constituents were performed as per WHO guidelines. Whole plant was sequ entially extracted into solvents with different polarities. Phytochemical screening and Thin Layer Chromatography (TLC) fingerprinting were carried out. Anatomical study and powder microscopy revealed useful diagnostic features. Physicochemical parameters such as moisture content, ash values (total, acid insoluble, water soluble) and extractable matter in water and ethanol were evaluated. Phytochemical screening and TLC fingerprinting revealed the presence of different types of phyto - constituents. Alkaloid, tannin, saponin, total flavonoid and total polyphenol contents were quantified. In conclusion, pharmacognostical study aids in establishing the standardization parameters of E. prostrata found in Sri Lanka.

Eclipta prostrata Linn. es una planta herbácea anual utilizada en la medicina tradicional, comúnmente conocida como "Trailing Eclipta" o False Daisy en inglés, 'Keekirindiya' en sinhala y 'Kayyan takara' en tamil. El objetivo de este estudio fue realizar una evaluación farmacognóstica detallada de E. prostrata encontrada en Sri Lanka. Se llevaron a cabo estudios anatómicos, fisicoquímicos, fitoquímicos y cuantificación de fitoconstituyentes según l as directrices de la OMS. Se extrajo secuencialmente la planta entera en solventes con diferentes polaridades. Se realizaron pruebas de tamizaje fitoquímico y huellas dactilares de cromatografía en capa delgada (TLC). El estudio anatómico y la microscopía en polvo revelaron características diagnósticas útiles. Se evaluaron parámetros fisicoquímicos como el contenido de humedad, los valores de ceniza (total, insoluble en ácido, soluble en agua) y la materia extraíble en agua y etanol. Las pruebas de tamizaje fitoquímico y las huellas dactilares de TLC revelaron la presencia de diferentes tipos de fitoconstituyentes. Se cuantificaron los contenidos de alcaloides, taninos, saponinas, flavonoides totales y polifenoles totales. En conclusión, el estudio farmacogn óstico ayuda a establecer los parámetros de estandarización de E. prostrata encontrada en Sri Lanka.

Combined Application of Fluorescence Spectroscopy and Principal Component Analysis in Characterisation of Selected Herbhoneys.

This study reports the use of front-face fluorescence spectroscopy with principal component analysis (PCA) as a tool for the characterisation of selected Polish herbhoneys (raspberry, lemon balm, rose, mint, black current, instant coffee, pine, hawthorn, and nettle). Fluorimetric spectra registered in the ranges ascribed to fluorescence of amino acids, polyphenols, vitamins, and products of Maillard's reaction enabled the comparison of herbhoney compositions. Obtained synchronous spectra combined with PCA were used to investigate potential differences between analysed samples and interactions between compounds present in them. The most substantial influence on the total variance had the intensities of polyphenols fluorescence. These intensities were the main factor differentiated by the analysed products.

Characterization and stability assessment of polyphenols bound to Lycium barbarum polysaccharide: Insights from gastrointestinal digestion and colon fermentation.

Polysaccharides and polyphenols are biologically active components that coexist in Lycium barbarum fruit, and there may be interactions between them that affect the release of each other. In this study, polyphenols bound to L. barbarum polysaccharide (LBP) were characterized, and the stability of bound phenolics (BP) was assessed by gastrointestinal digestion and colon fermentation. The results showed that a total of 65 phytochemicals such as flavonoids, phenolic acids, and coumarins were identified by UPLC-MS/MS. Quantitative analysis revealed that the major phenolic constituents were rutin, p-coumaric acid, catechin, ferulic acid, protocatechuic acid, and gallic acid, and their contents were 58.72, 24.03, 14.24, 13.28, 10.39, and 6.7 mg GAE/100 g DW, respectively. The release of BP by gastric digestion and gastrointestinal digestion was 9.67 % and 19.39 %, respectively. Most polyphenols were greatly affected by gastric digestion, while rutin was released in small intestine. The BP were fully released (49.77 %) and metabolized by gut microorganisms, and a considerable number of intermediates and end-products were detected, such as phloroglucinol, phenylacetic acid, and phenyllactic acid. Microbiomics data emphasized the positive impact of LBP on gut bacteria of Bacteroides, Parabacteroides, and Clostridioides. These findings could deepen our understanding of the bioavailability and biological fate of BP and also provide reference data for nutrient release and utilization of L. barbarum as a whole.

Polyphenol recovery from sorghum bran waste by microwave assisted extraction: Structural transformations as affected by grain phenolic profile.

Sorghum milling waste stream (bran), contains diverse phenolic compounds with bioactive properties. The study determined the potential of microwave assisted extraction (MAE) to recover the bran phenolic compounds. Red, white, and lemon-yellow pericarp sorghum brans were subjected to MAE and phenolic yield and structural transformation vs conventional extraction (control) assessed by UPLC-MS/MS, Folin-Ciocalteu and Trolox equivalent antioxidant capacity methods. Phenols yield increased from 3.7-20.3 to 12.6-75.5 mg/g, while antioxidants capacity increased average 3.3X in MAE extracts vs controls. Hydroxycinnamic acids increased most dramatically (3.0-32X) in MAE extracts (0.08-2.64 to 2.57-8.01 mg/g), largely driven by release of cell-wall derived feruloyl- and coumaroyl-arabinose. MAE hydrolyzed flavonoid glycosides into aglycones, and depolymerized condensed flavonoid heteropolymers into flavanones, flavanols and (deoxy)anthocyanidins. Thus, MAE dramatically enhances yield of valuable phenolics from sorghum bran waste, but also alters the phenolic profile in ways that may influence their chemical and biological properties.

Chemical, sensory and biological variations of black tea under different drying temperatures.

As the final processing step, drying temperature between 90 and 140 â„ƒ is usually applied to terminate enzymatic activities and improve sensory characteristics of black tea. Liquid chromatography tandem mass spectrometry (LC-MS) based non-targeted and targeted metabolomics analyses combined in vitro biological assays were adopted to investigate the chemical and biological variations after drying. Fifty-nine differentially expressed metabolites including several hydroxycinnamic acid derivatives and pyroglutamic acid-glucose Amadori rearrangement products (ARPs) were identified, the latter of which was correspondingly accumulated with increasing temperature. The levels of theaflavins (TFs), thearubigins (TRs), monosaccharides and free amino acids gradually decreased with increasing temperature. Furthermore, the bioassays of black tea showed that drying under 110 â„ƒ provided the highest antioxidant capacities, but the inhibitory effects on α-glucosidase and α-amylase were decreasing along with increasing drying temperature. These results are valuable for optimizing drying process to obtain superior sensory properties and preserve bioactivities of black tea.

Effect of microwave-assisted drying and extraction of 6-Shogaol from Zingiber officinale Roscoe.

Ginger (Zingiber officinale Roscoe, Zingeberaceae) is a medicinal plant widely used as food, spice, or flavoring agent worldwide. 6-Shogaol is a compound of prime interest in exhibiting anti-inflammatory, antioxidant and chemopreventive effects. The objective of the study is to investigate the effect of microwave-assisted drying (MAD) followed by microwave-assisted extraction (MAE) so as to produce 6-Shogaol enriched Ginger with improved therapeutic benefits. Various drying techniques viz. shade drying, tray drying, microwave-assisted drying and osmotic dehydration as a pretreatment were used for drying Ginger rhizomes. The dried rhizomes were extracted by conventional solvent extraction and microwave-assisted extraction techniques and tested for content of 6-Shogaol using the newly developed HPLC method whereas total flavonoid and polyphenol content were determined using the UV spectrophotometric method. Subjecting the microwave dried Ginger to microwave-assisted extraction for 45 min at constant power level of 284 W resulted in a significant rise in the extractability of 6-Shogaol (1.660 ± 0.018), total polyphenols (855.46 ± 5.33) and flavonoids (617.97 ± 6.40) compared to the conventional method of extraction. The proposed Ginger processing method of microwave drying followed by microwave extraction outperforms traditional methods in terms of speed, convenience, and performance thus can be scaled up to industrial levels.

Biological activities, identification, method development, and validation for analysis of polyphenolic compounds in Nymphaea rubra flowers and leaves by UHPLC-Q-cIM-TOF-MS and UHPLC-TQ-MS.

INTRODUCTION: Nymphaea rubra belongs to the Nymphaea family and is regarded as a vegetable used in traditional medicine to cure several ailments. These species are rich in phenolic acid, flavonoids, and hydrolysable tannin. OBJECTIVE: This study aimed to assess the biological activities of Nymphaea rubra flowers (NRF) and leaves (NRL) by identifying and quantifying their polyphenolic compounds using ultra-performance liquid chromatography coupled to quadrupole cyclic ion mobility time-of-flight mass spectrometry (UHPLC-Q-cIM-TOF-MS) and triple quadrupole mass spectrometry (UHPLC-TQ-MS). METHODOLOGY: NRF and NRL powder was extracted with methanol and fractionated using hexane, ethylacetate, and water. Antioxidant and α-glucosidase, and tyrosinase enzyme inhibitory activities were evaluated. The polyphenolic components of NRF and NRL were identified and quantified using UHPLC-Q-cIM-TOF-MS and UHPLC-TQ-MS. The method was validated using linearity, precision, accuracy, limit of detection (LOD), and lower limit of quantification (LLOQ). RESULTS: Bioactive substances and antioxidants were highest in the ethylacetate fraction of flowers and leaves. Principal component analysis showed how solvent and plant components affect N. rubra's bioactivity and bioactive compound extraction. A total of 67 compounds were identified, and among them 21 significant polyphenols were quantified. Each calibration curve had R2 > 0.998. The LOD and LLOQ varied from 0.007 to 0.09 µg/mL and from 0.01 to 0.1 µg/mL, respectively. NRF contained a significant amount of gallic acid (10.1 mg/g), while NRL contained abundant pentagalloylglucose (2.8 mg/g). CONCLUSION: The developed method is simple, rapid, and selective for the identification and quantification of bioactive molecules. These findings provide a scientific basis for N. rubra's well-documented biological effects.

Dietary polyphenol intake in the Canadian population: Findings from the 2015 Canadian Community Health Survey-Nutrition.

OBJECTIVES: This study aimed to estimate usual polyphenol intake among Canadians using the nationally representative 2015 Canadian Community Health Survey-Nutrition and to explore the main dietary contributors to polyphenol intake and the sociodemographic and lifestyle factors that may impact polyphenol intake. METHODS: Dietary information was collected from 19,409 respondents using 24-h dietary recalls. The polyphenol content of foods was estimated using the Phenol-Explorer Database (version 3.6). Daily intake values for total polyphenols (adjusted to energy intake), main classes, and subclasses were calculated for each respondent and dietary recall. Usual intake was estimated by age/sex groups and by sociodemographic and lifestyle characteristics independently for adults and children using the National Cancer Institute method. Given-day arithmetic mean polyphenol intakes and mean proportions of main classes contributing to sum total polyphenol intakes were explored. Population proportions were used to determine dietary contributors. RESULTS: Usual total polyphenol intake was 1119.3 mg/1000 kcal/day (95% CI: 1090.5, 1148.1) for adults ≥ 19 years and 473.0 mg/1000 kcal/day (95% CI: 454.9, 491.0) for children 2‒18 years. Generally, total polyphenol intakes differed by age, sex, ethnicity, and household education status and were higher among coffee and tea consumers. Most polyphenols came from flavonoids (40.0%) and phenolic acids (49.8%), with children consuming more flavonoids and other polyphenols and adults more phenolic acids. The top food contributors to polyphenol intake were coffee (26.8%), tea (8.9%), fruit juice (4.2%), banana (4.1%), and apple (3.8%). CONCLUSION: Usual intake of total polyphenols among Canadians differed primarily by age. Non-alcoholic beverages were top contributors to total polyphenol intake.

RéSUMé: OBJECTIFS: Notre étude visait à estimer l'apport habituel en polyphénols des Canadiens et des Canadiennes à l'aide de l'Enquête sur la santé dans les collectivités canadiennes ­ Nutrition 2015 (une enquête nationale représentative) et à explorer les principaux aliments qui contribuent à l'apport en polyphénols, ainsi que les facteurs sociodémographiques et les aspects du mode de vie qui peuvent influencer cet apport. MéTHODE: Les informations relatives à l'alimentation proviennent de 19 409 répondants et ont été obtenues à l'aide de feuilles de rappel des aliments ingérés pendant les 24 dernières heures. Nous avons estimé la teneur en polyphénols des aliments à l'aide de la base de données Phenol-Explorer (version 3.6). Nous avons calculé les valeurs de l'apport quotidien total en polyphénols (ajusté en fonction de l'apport énergétique), les catégories principales et les sous-catégories pour chaque répondant et chaque feuille de rappel. Nous avons estimé l'apport habituel par groupe d'âge et de sexe et selon les caractéristiques sociodémographiques et les aspects du mode de vie, indépendamment pour les adultes et les enfants, à l'aide de la méthode de l'Institut national du cancer. Nous avons également exploré la moyenne arithmétique des apports en polyphénols et les proportions moyennes des principales catégories contribuant au total des apports en polyphénols à une date précise. Les proportions de la population ont servi à déterminer les aliments contribuant aux apports en polyphénols. RéSULTATS: L'apport habituel total en polyphénols était de 1119,3 mg/1000 kcal/jour (IC de 95% : 1090,5, 1148,1) pour les adultes ≥ 19 ans et de 473,0 mg/1000 kcal/jour (IC de 95% : 454,9, 491,0) pour les enfants de 2 à 18 ans. En général, les apports totaux en polyphénols différaient selon l'âge, le sexe, l'ethnicité et le niveau d'instruction du ménage, et ils étaient plus élevés chez les consommateurs de café et de thé. La plupart des polyphénols provenaient des flavonoïdes (40,0 %) et des acides phénoliques (49,8 %); les enfants consommaient davantage de flavonoïdes et d'autres polyphénols, et les adultes, davantage d'acides phénoliques. Les principaux aliments contribuant à l'apport en polyphénols étaient le café (26,8 %), le thé (8,9 %), les jus de fruits (4,2 %), les bananes (4,1 %) et les pommes (3,8 %). CONCLUSION: L'apport habituel total en polyphénols chez les Canadiens et les Canadiennes différait principalement selon l'âge. Les boissons non alcoolisées étaient les principaux aliments contribuant à l'apport total en polyphénols.

Ultrasound-assisted extraction of polyphenols from pine needles (Pinus elliottii): Comprehensive insights from RSM optimization, antioxidant activity, UHPLC-Q-Exactive Orbitrap MS/MS analysis and kinetic model.

Extracting polyphenolic bioactive compounds from Pinus elliottii needles, a forestry residue, promises economic and environmental benefits, however, relevant experimental data are lacking. Herein, a comprehensive investigation of the polyphenolic composition of pine needles (PNs) was carried out. Ultrasound-Assisted Extraction (UAE) was applied to extract the polyphenolic compounds of pine needles. The optimal conditions of extracts were determined by Response Surface Methodology (RSM). The maximum total phenolic content (TPC) of 40.37 mg GAE/g PNs was achieved with solid-liquid ratio of 1:20, 60 % ethanol, and 350 W for 25 min at 45 °C. Polyphenolic extracts showed antioxidant activity in scavenging free radicals and reducing power (DPPH, IC50 41.05 µg/mL; FRAP 1.09 mM Fe2+/g PNs; ABTS, IC50 214.07 µg/mL). Furthermore, the second-order kinetic model was also constructed to describe the mechanism of the UAE process, with the extraction activation energy estimated at 12.26 kJ/mol. In addition, 37 compounds in PNs were first identified by UHPLC-Q-Exactive Orbitrap MS/MS, including flavonoids and phenolic acids. The results suggest that Ultrasound-Assisted is an effective method for the extraction of natural polyphenolic compounds from pine needles and this study could serve as a foundation for utilizing phenolics derived from PNs in the food and pharmaceutical industries.

Polyphenol Contents, Gas Chromatography-Mass Spectrometry (GC-MS) and Antibacterial Activity of Methanol Extract and Fractions of Sonneratia Caseolaris Fruits from Ben Tre Province in Vietnam.

Plants contain a large number of phytochemical components, many of which are known as bioactive compounds and responsible for the expression of various pharmacological activities. The extract of Sonneratia caseolaris fruit collected in Vietnam was investigated for its total phenolic and total flavonoid contents using methanol solvent and different fractions of S. caseolaris fruits (hexane, ethyl acetate, n-butanol, and aqueous). GC-MS analysis was conducted to identify the bioactive chemical constituents occurring in the active extract. Further, the antibacterial activity was tested in vitro on bacterial isolates, namely Escherichia coli, Staphylococcus aureus, and Bacillus subtilis, using the disc diffusion method on tryptic soya agar (TSA) medium. The methanol extract showed high total flavonoid (82.3 ± 0.41 mg QE/g extract) and phenolic (41.0 ± 0.34 mg GAE/g extract) content. GC-MS of the methanol extract and different fractions of S. caseolaris fruits detected 20 compounds, principally fatty alcohols, fatty acids, phenols, lipids, terpenes derivatives, and carboxylic acids derivatives. A 50 mg/ml concentration of methanol extract had the strongest antibacterial activity on E. coli, S. aureus, and B. subtilis. Furthermore, ethyl acetate, aqueous, and n-butanol fractions inhibited S. aureus and B. subtilis the most. The results of the present study suggested that the fruits of S. caseolaris are rich sources of phenolic compounds that can contribute to safe and cost-effective treatments.

Partitioning and in vitro bioaccessibility of apple polyphenols during mechanical and physiological extraction: A hierarchical clustering analysis with LC-ESI-QTOF-MS/MS.

Polyphenol partitioning during mechanical (cold-pressing) and physiological (digestion) extraction at the individual polyphenol and subclass level was investigated. UHPLC-ESI-QTOF-MS/MS analysis yielded a comprehensive identification of 45 polyphenols whose semi-quantification revealed a hierarchical clustering strongly determined by polyphenol structure and their location within the apple tissue. For instance, pomace retained most flavonols and flavanols (degree of polymerization DP 5-7), which were highly hydrophobic, hydroxylated, or large (>434 Da), and more abundant in peel. In vitro digestion UHPLC-ESI-QTOF-MS/MS analysis of whole apple (and its corresponding matrix-free extract) clustered polyphenols into five main groups according to their interaction with plant cell walls (PCWs) during each digestion phase. This grouping was not reproduced in pomace, which exhibited a greater matrix effect than whole apple during oral and gastric digestion. Nevertheless, the interaction between most polyphenol groups, including dihydrochalcones, flavanols (DP 1-4) and hydroxycinnamic acid derivatives, and pomace PCWs was lost during intestinal digestion.

Precise evaluation of batch adsorption kinetics of plant total polyphenols based on a flow-injection online spectrophotometric method.

Efficient evaluation of adsorption kinetics of plant total polyphenols is essential for the design of adsorption separation of bioactive compounds. The conventional method uses manual sampling with poor reproducibility. Here, we developed a new method for on-line determination of total polyphenol content (TPC) in plant extracts by applying the Folin-Ciocalteu method in flow-injection analysis (FIA). The FIA parameters were optimized and a standard curve with excellent linearity was established. Precise determination of TPC with a satisfactory sample throughput of 20 h-1 was achieved for the adsorption kinetic study. The pseudo-second-order kinetic model was found to better describe the kinetic parameters of the batch adsorption/desorption process. The developed method proved to be accurate compared with the conventional method. The FIA method holds significant promise for studying and monitoring adsorption processes, due to its automatic on-line nature, low consumption of reagents and samples, and the ability to generate large quantities of highly accurate adsorption data.

Optimizing the ultrasonic extraction of polyphenols from mango peel and investigating the characteristics, antioxidant activity and storage stability of extract nanocapsules in maltodextrin/whey protein isolate.

In this study, the extraction and nanoencapsulation of mango peel extract (MPE) were investigated to enhance its stability and preserve its antioxidant properties. Initially, using the central composite design (CCD)-response surface methodology (RSM), optimal conditions for the extraction of MPE via an ultrasonic system were determined to be a temperature of 10.53 °C, a time of 34.35 min, and an ethanol concentration of 26.62 %. Subsequently, the extracted extract was spray-dried and nanoencapsulated using three types of coatings: maltodextrin, whey protein isolate (WPI), and their combination. The results showed that nanoencapsulation led to a significant improvement in the stability of phenolic compounds in the extract during storage compared to free extract. Furthermore, capsules prepared with the combined coating exhibited the highest levels of phenolic compounds and antioxidant activity. Therefore, it can be concluded that nanoencapsulation can serve as an effective method for preserving the bioactive properties of MPE.

Optimization of ultrasound- and enzymatic-assisted extractions of polyphenols from dried red onion peels and evaluation of their antioxidant activities.

There is a recognized need for exploring new natural antioxidants that have high antioxidant potential. Thus, the aim of this study was to optimize the extraction process of onion peels using ultrasound- and enzymatic-assisted extractions (UAE and EAE) methods to utilize the optimal extracts as natural antioxidants. Box-Behnken Design (BBD) was implemented to reach the optimal extracts with the highest simultaneous content of total phenolic content (TPC) and total flavonoid content (TFC). The optimal UAE and EAE extracts were subjected to High Performance Liquid Chromatography (HPLC) analysis to identify their chemical profile. The antioxidant activities of optimal extracts obtained by UAE and EAE were evaluated in vitro using DPPH and FRAP assays and their abilities to increase the oxidative stability of sunflower oil were studied using Rancimat test. The optimal conditions for UAE were 34.02 W, 26.87 mL/g solid, and 45.43 min, meanwhile they were 30.00 mL/g solid, 45.43 min at enzyme concentration of 0.52% for EAE method. DPPH and FRAP assays results revealed that EAE optimal extract show superior antioxidant activity over UAE optimal extract. The protection factor of optimal EAE extract against sunflower oil oxidation was close to that of butylated hydroxytoluene (BHT).

Application of vibrational and fluorescence spectroscopy to the compositional analysis of colored-flesh potatoes.

BACKGROUND: Determination of composition and physicochemical parameters of natural products requires dedicated, often laborious and expensive, analytical protocols. Different spectroscopic techniques, in conjunction with chemometrics, seem to have a considerable potential in direct analysis of raw plant material and foods, without any chemical treatment. RESULTS: Fluorescence spectroscopy and three vibrational spectroscopy techniques were applied to determine total polyphenol content, antioxidant activity and macronutrient levels in red- and purple-fleshed potato varieties. Excitation-emission matrix fluorescence, Fourier transform Raman, attenuated total reflection Fourier transform infrared and near-infrared spectra were recorded for the freeze-dried samples. Combining spectral data and the results of reference analyses, partial least squares regression models were constructed for each parameter studied. For polyphenols and antioxidant activity, quantification errors found for validation samples amounted to 3.74-5.04% and 4.75-6.35%, respectively, whereas macronutrient analysis gave errors in the 3.45-4.55%, 3.09-5.30% and 5.10-8.58% ranges for starch, protein and sugar determinations, respectively. CONCLUSION: The obtained results demonstrate that different spectroscopic techniques in combination with multivariate modeling allow simultaneous determination of various parameters of plant samples based on a single sample spectrum. They can effectively replace commonly used protocols of food product analysis requiring sample dissolving and extraction of the compounds of interest. © 2023 Society of Chemical Industry.