Total Proanthocyanidin Contents Research Articles

Transcriptome and weighted gene co-expression network analysis reveal key genes involved in the proanthocyanidin biosynthesis in Cerasus humilis

Proanthocyanidins (PAs), contributing greatly to the antioxidant activity, are among the most abundant flavonoid components in Cerasus humilis fruits. In this study, contents of six different PA components and total PAs in fruits of two C. humilis varieties (‘Jinou1’ and ‘DS-1′) were determined at four different ripening stages. Results showed that, five PA components and the total PAs contents of ‘Jinou1’ were notedly higher than that of ‘DS-1′ except proanthocyanidins A1. All PA components showed a general decreasing trend during ripening, and dropped to their lowest levels at the fully ripe stage. In ripe C. humilis fruits, the major PA was catechin, the content of which undergoes considerable changes during fruit ripening. The key genes involved in PA biosynthesis were explored based on the transcriptome profiles, and their co-expression networks were constructed. Transcriptomic analysis identified 19 PA biosynthesis-related structural genes as differentially expressed genes (DEGs). The highly expressed MSTRG.938 (LAR, leucoanthocyanidin reductase), MSTRG.4502 (ANR, anthocyanidin reductase), and MSTRG.4956 (PAL, phenylalanine ammonia lyase) genes may play key roles in regulating PA accumulation. Moreover, through weighted gene co-expression network analysis (WGCNA), we constructed a gene regulatory network of two modules involving 15 PA biosynthesis-related DEGs, and the expression changes in 10 of them were validated using quantitative real-time PCR. These results indicated that they are key contributors to the PA biosynthesis in C. humilis fruits. Our study will aid in elucidating the molecular mechanisms underlying PAs accumulation in C. humilis fruits.

Valorization of avocado peels by conventional extraction and hydrothermal carbonization for cosmeceutical applications

Avocado peels (APs) are an agro-industrial non-edible residue from avocado processing industries that lack commercially valuable applications despite their content of bioactive molecules. This work investigates for the first time the combined use of conventional extraction with hydrothermal carbonization (HTC) as a new strategy to maximize the bioactive fractions obtained from APs for potential cosmeceutical applications. APs were extracted by maceration, while the extracted biomass was subjected to HTC at 200, 250, and 300 °C. The ethanolic extract (EEPA), liquid phases (LBOs), and heavy bio-oils (HBOs) were characterized by FTIR, and their content of total phenol, hydroxycinnamic acids, flavonoids, and proanthocyanidins were further determined. The antioxidant properties of all fractions and their effects on tyrosinase and elastase activities were spectrophotometrically analyzed, whereas the most promising fractions were examined by GC-MS. LBOs were rich in total phenols, hydroxycinnamic acids, and flavonoids, whereas EEPA showed the highest content of proanthocyanidins. EEPA and LBOs exhibited the highest antioxidant ability. In contrast, HBOs had significant inhibitory effects on tyrosinase and elastase activities, higher than those of kojic acid and epigallocatechin gallate, used in the cosmeceutical industry to counteract hyperpigmentation and skin flaccidity, respectively. Esters (42 %) were the dominant molecules identified in EEPA, while phenols prevailed in LBO 250 °C (45 %) and HBO 250 °C (22%). These results open the way to apply conventional extraction and HTC as a new strategy for recycling avocado waste to develop sustainable cosmeceutical products.

The Extraction Process, Separation, and Identification of Curcuminoids from Turmeric Curcuma longa.

Turmeric Curcuma longa is a well-known spice with various health benefits, attributed primarily to curcumin. Soxhlet extraction, cold maceration, ultrasound-assisted extraction (UAE), and supercritical fluid extraction were performed, and the content of total phenols, proanthocyanidins, and antioxidants was analysed by UV/VIS spectrophotometry. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was employed to identify and quantify the curcumin content. Supercritical extracts had the highest total phenolic content (538.95 mg GA/100 g material), while the Soxhlet extracts had the highest content of proanthocyanidins (4.77 mg PAC/100 g of material). Extracts obtained by UAE and supercritical extraction have the highest antioxidant potential. Antioxidant activity measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH•) was 64.27% and 1750.32 mg Trolox per g dry weight by 2,2-azinobis(3-ethylbenzothiazoline 6 sulphonic acid) (ABTS+•) for the extract obtained by supercritical extraction. The UAE resulted in the highest amount of curcumin (1.91 mg curcumin/g material). A kinetic study showed that extraction yield in supercritical extracts decreased with increasing temperature and that the content of isolated curcumin was inversely proportional to solvent-to-feed ratio (S/F). The present study has confirmed that turmeric is an excellent source of antioxidants, such as curcumin, that play an important role in reducing cellular stress by neutralising free radicals.

Phytochemical screening, total phenolic content and antioxidant activities of Marrubium vulgare L. collected in three development stages

The change of phenolic compounds and antioxidant activities of plants extracts are widely attributed to numerous conditions and parameters viz. geographical conditions, type of extraction, and type of extract. Thus, this study was the first one conducted to evaluate the phenolic composition, the content of total polyphenols, flavonoids, and proanthocyanidins, and the antioxidant activities of methanolic extract of M. vulgare aerial part collected in three development stages (before flowering, during flowering, and after flowering periods). Phytochemical screening was carried out using standard methods of precipitation and coloration reactions. The total polyphenol, flavonoid, and proanthocyanidins contents were determined using the Folin-Ciocalteu method, aluminum chloride colorimetric method, and vanillin method, respectively. The antioxidant activity was assessed by two methods: DPPH and ABTS scavenging activity. Preliminarily phytochemical screening revealed the presence of saponins, essential oil, cardiac glucosides, sterols and triterpenes, and the absence of alkaloids. In addition, tannins were absence in March and present in May and July. The total phenol content of M. vulgare extracts showed a highest flavonoid and proanthocyanidin contents during flowering period (1.644 mg QE.g-1 extract, and 0.195 mg CE.g-1 extract, respectively) while polyphenol content was highest before flowering period (0.043 mg GAE.g-1 extract). Afterward, M. vulgare methanolic extract exhibited a potent antioxidant activity during flowering period with an IC50 value of 2.23 mg.ml-1. From the current study, this plant contains natural antioxidant substances which can be used as antioxidant agents to treat several diseases.

Extraction of Functional Compounds from Tarragon (Artemisia dracunculus L.) by Deep Eutectic Solvents at Different Properties.

In this study, it was aimed to examine the capacity of deep eutectic solvents (DESs) with different contents to extract bioactive compounds from tarragon (Artemisia dracunculus L.) plant. For this reason, the total phenolic-flavonoid substance, total proanthocyanidin content and antioxidant/antimicrobial activities of the prepared DES extracts were investigated, as well as the individual phenolic contents and individual amino acid contents. According to the results, DES10 had the highest efficiency in terms of its capacity to extract individual phenolics (approximately 59 mg/100g) and individual amino acids (approximately 2500 mg/kg), and also gave a higher yield compared to ethanol (approximately 44 mg/100g for individual phenolics and about 19810 mg/kg for individual amino acids) and methanol (approximately 58 mg/100g for individual phenolics and approximately 21430 mg/kg for individual amino acids). However, the total phenolic content, total flavonoid content and antioxidant activity values of DES extracts were determined between 59.09-77.50 mg GAE/100g, 28.68-45.55 mg GAE/100g and 42.96 mg TE/100g-146.86 mg TE/100g, respectively. Therefore, it can be recommended to use these green solvents, which are known as environmentally friendly, as an alternative to organic solvents in the process of preparing extracts of this important medicinal plant in different areas.

Protective Effects of Proanthocyanidin-Rich Fraction from Red Rice Germ and Bran on Lung Cell Inflammation via Inhibition of NF-κB/NLRP3 Inflammasome Pathway.

The activation of the NLRP3 inflammasome pathway during infectious pathogen-induced immunopathology can lead to chronic inflammation and various adverse health outcomes. Identification of functional foods with anti-inflammatory properties is crucial for preventing inflammation triggered by NLRP3 inflammasome activation. This study aimed to investigate the anti-inflammatory properties of a proanthocyanidin-rich fraction obtained from red rice germ and bran against lipopolysaccharide (LPS) and adenosine triphosphate (ATP)-induced condition in A549 lung cells. The proanthocyanidin-rich fraction from Yamuechaebia 3 red rice extract (YM3-PRF) was obtained using column chromatography with Sephadex LH20, and its total proanthocyanidin content was determined to be 351.43 ± 1.18 mg/g extract using the vanillin assay. A549 lung cells were pretreated with YM3-PRF at concentrations of 5-20 μg/mL prior to exposure to LPS (1 μg/mL) and ATP (5 nM). The results showed that YM3-PRF significantly inhibited the expression of inflammatory mRNAs (NLRP3, IL-6, IL-1β, and IL-18) and the secretion of cytokines (IL-6, IL-1β, and IL-18) in a dose-dependent manner (p < 0.05). Mechanistically, YM3-PRF exerted its anti-inflammatory effects by inhibiting NF-κB translocation and downregulating proteins associated with the NLRP3 inflammasome pathway (NLRP3, ASC, pro-caspase-1, and cleaved-caspase-1). These findings suggest that the proanthocyanidin-rich fraction from red rice germ and bran has protective effects and may serve as a potential therapeutic option for chronic inflammatory diseases associated with NLRP3 inflammasome activation.

Spray drying to produce novel phytochemical-rich ingredients from juice and pomace of American elderberry

The cultivation and commercialization of American elderberries (Sambucus nigra subsp. canadensis), rich in acylated anthocyanins, is nascent. In this study, American elderberry juice and pomace extract were spray dried using soy protein isolate (SPI) or tapioca starch (TS) as carriers to develop functional food ingredients. Physicochemical, morphological, and bioactive properties were analyzed, and an in vitro gastrointestinal digestion model was used to study polyphenol bioaccessibility. An efficient spray drying process (solids recovery >60%) was established. Elderberry particles produced with SPI had higher solubility (60%–64%), lower porosity (69%–70%), and better flowability (22% Carr index, 1.29 Hausner ratio). Spray dried particles produced with tapioca starch showed significantly higher total polyphenol content (42–49 mg gallic acid equivalent/g sample), proanthocyanidin content (0.76–2.86 mg proanthocyanidin-B2/g sample), and anthocyanins (7.86–33.80 mg/g sample) for both elderberry juice and pomace extract, compared to SPI-derived ones. Particles of encapsulated elderberry juice or pomace extract with SPI had higher bioaccessibility compared to non-encapsulated elderberry juice or TS-derived particles. Overall, spray drying American elderberry juice and pomace extract is an effective and sustainable strategy to create novel ingredients for multiple food applications. These findings offer an industry-friendly technological solution to develop value-added ingredients for the emerging American elderberry market.

A rapid chemometrics model for antioxidant substance mining of Chinese dwarf cherry [Cerasus humilis (Bge.) Sok.] based on polyphenol profile and antioxidant capacity of 30 germplasms

Chinese dwarf cherry (Ouli) is a native shrub in northwest China with high ecological value, but the nutritive potential remains to be explored. In this study, the total content of polyphenols, flavonoids, proanthocyanidins, and anthocyanins of Ouli from 30 germplasms were measured, and the antioxidant activities were evaluated by FRAP and ABTS assays. The polyphenol profile was determined by ultra-high-performance liquid chromatography-high resolution mass spectrometry. Grey relational analysis and partial least squares were utilized to build chemometrics models for selecting antioxidant compounds. The contents of total flavonoids, proanthocyanidins, phenols and total anthocyanidins of 30 germplasms of Ouli were 119.92–668.76 mg/100 g fresh weight (FW), 90.81–555.44 mg/100 g FW, 148.42–390.43 mg/100 g FW, 0.02–17.26 mg/100 g FW, respectively. A total of 61 compounds were identified, including 40 flavonoids (26 flavonols, 4 anthocyanins, 6 dihydroflavonols, 2 dihydrochalcones, and 2 flavones), 12 proanthocyanidins, 6 phenolic acids, and 3 types of other class compounds (one stilbene and two phenols). The proanthocyanidin compounds in Ouli contributes most to the total antioxidant capacity with the antioxidant rank that procyanidin trimer > tetramer > dimer ≈ monomer. Catechin and procyanidin B1 were the most abundant compounds and were 18.45–162.50 μg/g FW and 30.52–149.42 μg/g FW, respectively. Shanxi (SX) 2 and SX10 could be considered as potential germplasms, and proanthocyanidins could be chosen as a characteristic nutrient evaluation index of Ouli. This study not only takes a key step to lay the groundwork for further research of Ouli but also provides a reference for the discovery of the functional ingredients of other foods.

Genome‐wide analysis, metabolomics, and transcriptomics reveal the molecular basis of ZlRc overexpression in promoting phenolic compound accumulation in rice seeds

AbstractChinese wild rice (Zizania latifolia) is rich in phenolic compounds, particularly flavonoids. This study identified 203 basic helix‐loop‐helix (bHLHs) in Z. latifolia and showed that ZlbHLH196 (Zla16G011250) corresponds to the ZlRc gene in Z. latifolia, with its protein product localizing to the nucleus. Notably, the pericarps of ZlRc‐overexpressing (OE) rice are brown, whereas those of wild‐type (WT) rice are nonpigmented. The total phenolic, flavonoid, and proanthocyanidin contents, antioxidant activity, as well as enzyme inhibitory effects of ZlRc‐OE rice were significantly higher than those of WT rice. Overall, 221 differential phenolic metabolites were identified between ZlRc‐OE and WT rice, among which 198 were upregulated in the former. Additionally, a total of 227 differentially expressed genes were identified between ZlRc‐OE and WT rice, with 173 upregulated. Kyoto Encyclopedia of Genes and Genomes annotation and enrichment analysis of phenolic metabolites revealed enhanced isoflavonoid, flavone, flavonol, and flavonoid biosynthesis pathways in ZlRc‐OE rice, which, furthermore, showed a markedly upregulated expression and significantly higher activities of four key flavonoid biosynthesis–related enzymes (phenylalanine ammonia‐lyase, chalcone synthase, chalcone‐flavanone isomerase, and dihydroflavonol 4‐reductase). These findings show that ZlRc‐overexpression promotes phenolic compound accumulation in rice seeds and can be used to bioaugment rice phenolic content.

Changes in the Fruit Quality, Phenolic Compounds, and Antioxidant Potential of Red-Fleshed Kiwifruit during Postharvest Ripening

Kiwifruit is very popular for its unique flavor and nutritional value, and for its potential health benefits, which are closely related to its richness in a variety of natural antioxidant substances, in which polyphenolics play a non-negligible role. This study investigated changes in the fruit quality, phenolic compounds, and antioxidant potential of Chinese red-fleshed kiwifruit "Hongshi No. 2" during postharvest ripening at room temperature (20 ± 1 °C). Results showed that the weight loss rate slowly increased, the firmness rapidly decreased, and the soluble solid concentration gradually increased during the postharvest ripening of red-flesh kiwifruit. In addition, the total phenolic (TPC), total flavonoid (TFC), and total proanthocyanidin (TPAC) contents gradually increased during postharvest ripening. The most abundant phenolic compounds in kiwifruit throughout postharvest ripening were catechin (CC), proanthocyanidin B1 (PB1), and proanthocyanidin B2 (PB2). Furthermore, the methanolic extracts of red-flesh kiwifruit exhibited remarkable antioxidant activities throughout postharvest ripening stages. Indeed, some phenolic compounds showed good correlations with antioxidant activities; for instance, chlorogenic acid (CHL) showed a significantly positive correlation with ferric reducing antioxidant power (FRAP), and isoquercitrin (IS) showed a significantly negative correlation with DPPH free radical scavenging ability. The findings from this study are beneficial to better understanding the quality profile of red-flesh kiwifruit "Hongshi No. 2" during postharvest ripening.

Phytochemical Profiling of Extracts from Rare Potentilla Species and Evaluation of Their Anticancer Potential.

Despite the common use of Potentilla L. species (Rosaceae) as herbal medicines, a number of species still remain unexplored. Thus, the present study is a continuation of a study evaluating the phytochemical and biological profiles of aqueous acetone extracts from selected Potentilla species. Altogether, 10 aqueous acetone extracts were obtained from the aerial parts of P. aurea (PAU7), P. erecta (PER7), P. hyparctica (PHY7), P. megalantha (PME7), P. nepalensis (PNE7), P. pensylvanica (PPE7), P. pulcherrima (PPU7), P. rigoi (PRI7), and P. thuringiaca (PTH7), leaves of P. fruticosa (PFR7), as well as from the underground parts of P. alba (PAL7r) and P. erecta (PER7r). The phytochemical evaluation consisted of selected colourimetric methods, including total phenolic (TPC), tannin (TTC), proanthocyanidin (TPrC), phenolic acid (TPAC), and flavonoid (TFC) contents, as well as determination of the qualitative secondary metabolite composition by the employment of LC-HRMS (liquid chromatography-high-resolution mass spectrometry) analysis. The biological assessment included an evaluation of the cytotoxicity and antiproliferative properties of the extracts against human colon epithelial cell line CCD841 CoN and human colon adenocarcinoma cell line LS180. The highest TPC, TTC, and TPAC were found in PER7r (326.28 and 269.79 mg gallic acid equivalents (GAE)/g extract and 263.54 mg caffeic acid equivalents (CAE)/g extract, respectively). The highest TPrC was found in PAL7r (72.63 mg catechin equivalents (CE)/g extract), and the highest TFC was found in PHY7 (113.29 mg rutin equivalents (RE)/g extract). The LC-HRMS analysis showed the presence of a total of 198 compounds, including agrimoniin, pedunculagin, astragalin, ellagic acid, and tiliroside. An examination of the anticancer properties revealed the highest decrease in colon cancer cell viability in response to PAL7r (IC50 = 82 µg/mL), while the strongest antiproliferative effect was observed in LS180 treated with PFR7 (IC50 = 50 µg/mL) and PAL7r (IC50 = 52 µg/mL). An LDH (lactate dehydrogenase) assay revealed that most of the extracts were not cytotoxic against colon epithelial cells. At the same time, the tested extracts for the whole range of concentrations damaged the membranes of colon cancer cells. The highest cytotoxicity was observed for PAL7r, which in concentrations from 25 to 250 µg/mL increased LDH levels by 145.7% and 479.0%, respectively. The previously and currently obtained results indicated that some aqueous acetone extracts from Potentilla species have anticancer potential and thus encourage further studies in order to develop a new efficient and safe therapeutic strategy for people who have been threatened by or suffered from colon cancer.

HPLC analysis, mycochemical contents and biological activities of two edible hypogeous ascomycetes: Tirmania nivea and Terfezia boudieri

Truffle, the hypogeous, ascomycetous macrofungus, has been recognized as a delicacy for centuries, and it is gaining elevated status in the culinary domain. The chemical composition and biological activities of aqueous extract and ground material of two desert Tunisian Tirmania nivea and Terfezia boudieri were studied for the first time. Using three assays antioxidant activity of the aqueous extract and ground material of the two truffles were investigated. Indeed, the aqueous extract and ground material of Terfezia boudieri showed the highest capacity for the DPPH scavenging test (IC50 = 0.18 mg/mL) and with regard to the chelating power of iron (IC50 = 0.22 mg/mL). At the same time, the highest capacity for iron reduction was recorded in the crude material of Tirmania nivea. Besides, the total phenolic, flavonoid, flavanol, tannin, and proanthocyanidin contents of both truffles extracts were determined. The ground material showed the best antibacterial activity for two ascomycetes against seven strains of bacteria. HPLC analysis of aqueous extracts showed that the predominant phenolic compounds in T. boudieri and T. nivea were gallic acid (33.25%) and myricetin (52.91%). Therefore, these truffles are a source of natural antioxidant and antimicrobial agents and could be used as a potential health food.

Bioactive Compound Contents and Antioxidant Activity of Purified Red Sorghum Pericarp Extract by Membrane Ultrafiltration Process

Sorghum plants contain bioactive compounds such as phenolic compounds and proanthocyanidins. The presence of these compounds is extremely valuable for use as antioxidants in health care. This study aims to determine the total phenolic content, total proanthocyanidin content, and antioxidant activity of purified red sorghum extract using the ultrafiltration membrane method with different transmembrane pressure. At pressures of 8, 9, and 10 Bar, an ultrafiltration process was carried out using a polyethersulfone (PES) membrane with a molecular weight cut-off size of 10 kDa. The total phenolic content was determined using the Follin-Ciocalteu method and identified using UV-Vis spectrophotometry at 760 nm. Total proanthocyanidin content was measured using the acid-butanol method and then analyzed using UV-Vis spectrophotometry at 550 nm. The DPPH (2,2-diphenyl-2-picrylhydrazyl) method will be used to determine the antioxidant activity of purified red sorghum extract. The results of the measurements show that the higher the transmembrane pressure, the higher the concentration of phenolic and proanthocyanidins content, and that the purified red sorghum extract has a high antioxidant value (IC 50 = 66.852 ppm).

Comparison of Proanthocyanidin Content in Rabbiteye Blueberry (Vaccinium virgatum Aiton) Leaves and the Promotion of Apoptosis against HL-60 Promyelocytic Leukemia Cells Using ‘Kunisato 35 Gou’ Leaf Extract

Polyphenol-rich rabbiteye blueberry (Vaccinium virgatum Aiton) leaves have attracted attention as a food material. In this study, we compared the total polyphenols, total proanthocyanidin content, and antioxidant activity of the leaves of 18 blueberry varieties and investigated the seasonal variation in polyphenols. We also evaluated the anti-cancer cell proliferation properties of the rabbiteye blueberry leaf specific cultivar 'Kunisato 35 Gou'. Rabbiteye blueberry leaves had significantly higher total polyphenol and total proanthocyanidin values than northern highbush blueberry and southern highbush blueberry leaves. The antioxidant activity of blueberry leaves was highly positively correlated with both the total polyphenol and total proanthocyanidin content. Variations were observed in the total polyphenol and total proanthocyanidin content of rabbiteye blueberry leaves harvested at different points in the growing season; leaves collected in fall to winter contained more epicatechin in addition to proanthocyanidins. In the evaluation of anti-cancer cell proliferation properties against HL-60 promyelocytic leukemia cells, the September-harvested extracts of rabbiteye blueberry 'Kunisato 35 Gou' showed strong properties, and the use of an FITC Annexin V apoptosis detection kit with propidium iodide confirmed that this HL-60 cell death occurred via apoptosis. Limiting the harvest time would make rabbiteye blueberry leaves a more functional food ingredient.

Influence of Different Precursors on Content of Polyphenols in Camellia sinensis In Vitro Callus Culture

Plant tissue cultures are considered as potential producers of biologically active plant metabolites, which include various phenolic compounds that can be used to maintain human health. Moreover, in most cases, their accumulation is lower than in the original explants, which requires the search for factors and influences for the intensification of this process. In this case, it is very promising to use the precursors of their biosynthesis as potential "regulators" of the various metabolites' formation. The purpose of our research was to study the effect of L-phenylalanine (PhA, 3 mM), trans-cinnamic acid (CA, 1 mM) and naringenin (NG, 0.5 mM), as components of various stages of phenolic metabolism, on accumulation of various phenolic compound classes, including phenylpropanoids, flavans and proanthocyanidins, as well as the content of malondialdehyde in in vitro callus culture of the tea plant (Camellia sinensis L.). According to the data obtained, the precursors' influence did not lead to changes in the morphology and water content of the cultures. At the same time, an increase in the total content of phenolic compounds, as well as phenylpropanoids, flavans and proanthocyanidins, was noted in tea callus cultures. Effectiveness of precursor action depends on its characteristics and the exposure duration, and was more pronounced in the treatments with PhA. This compound can be considered as the most effective precursor regulating phenolic metabolism, contributing to a twofold increase in the total content of phenolic compounds, flavanes and proanthocyanidins, and a fourfold increase in phenylpropanoids in tea callus cultures.

Changes in the Composition of Biologically Active Compounds during the Ripening Period in Fruit of Different Large Cranberry (Vaccinium macrocarpon Aiton) Cultivars Grown in the Lithuanian Collection.

In our investigation, we evaluated the content of chlorogenic acid, proanthocyanidins, anthocyanins, flavonols, triterpenoids, and phytosterols in cranberry fruit extracts of the cultivars ‘Baifay’, ‘Early Black’, ‘Howes’, ‘Pilgrim’, ‘Red Star’, and ‘Stevens’ grown in Lithuania, as well as changes in the antioxidant activity in extracts of fruit samples of these cultivars during the period of berry maturation. The highest amount of proanthocyanidins (8.87 ± 0.57 mg EE/g EE) and flavonols (3688.52 ± 22.85 µg/g) was determined in cranberries of the cultivar ‘Howes’ harvested on 12 August. Remarkably, the highest anthocyanins content (9628.62 ± 266 µg/g) was determined in cranberries of the cultivar ‘Howes’ harvested on 22 October. The study showed that the content of phytochemical compounds in cranberries varied between 12 August and 22 October; the content of proanthocyanidins decreased by a factor of about 2, the content of chlorogenic acid decreased by a factor of about 1.3, the content of flavonols decreased by a factor of about 2, and the content of anthocyanins increased by 27 to 450 times. A strong correlation was found between the total proanthocyanidin content of cranberry fruit extracts and their in vitro antiradical and reducing activity (r = 0.781 and 0.726, respectively, p < 0.001). The data of our study detail the accumulation of the phytochemical composition of biologically active compounds in cranberry samples during the stages of maturity, therefore these data are significant for the assessment of harvest time of cranberry and can be applied to select cranberry cultivars for further cultivation in Lithuanian climatic conditions.

Characterization of the Bioactive Components in Aronia melanocarpa (Black Chokeberry) Fruit Extracts and Purified Fractions by Spectrophotometry and High-Performance Liquid Chromatography (HPLC)

Black chokeberry (Aronia melanocarpa L.) fruit has long been used as a functional food in various forms. The main bioactive components are proanthocyanidins, anthocyanins, flavonoids, and phenolic compounds, all of which have various bioactivities. However, most previous studies have focused on the component analysis of black chokeberries and not on the effects of processing methods. Therefore, the purpose of this study was to compare the contents of the major components of freeze-dried ethanol extracts (FEEs) and purified aronia bioactive fractions (ABFs). The main components were determined using an ultraviolet-visible spectrophotometer, whereas individual compounds were quantified by high-performance liquid chromatography (HPLC). Consequently, the total anthocyanin, proanthocyanidin, and flavonoid contents were determined to be 1.55%, 7.95%, and 0.42% in FEEs, and 17.7%, 38.0%, and 4.05% in ABFs. The total content of each chemical group in the ABF samples was 4.9 to 11.4 times higher than in the FEE samples. Additionally, individual sugars and organic acids were quantified in the FEE samples, with determined compositions of 9.20% malic acid, 2.70% quinic acid, 18.1% fructose, 16.3% glucose, and 25.4% sorbitol. These compounds were not detected in the ABF samples. Furthermore, the bioactivities of the ABF and FEE samples were compared by evaluating the antioxidant activities using the DPPH (2,2-diphenyl-1-picrylhydrazyl) method. The ABF samples showed better antioxidant effects than the FEE samples. Collectively, the processed ABF samples enhanced the bioactivity of black chokeberry fruits, enabling their effective application as novel functional foods.

Chemical and Functional Characterization of Extracts from Leaves and Twigs of Acacia dealbata

The purpose of this work was to evaluate the recovery of bioactive extracts from Acacia dealbata leaves and twigs and to characterize their chemical composition and functional properties. Fresh and air-dried samples were extracted by maceration at room temperature and by hot extraction at 60 °C using aqueous solutions of acetone, ethanol, and methanol. The highest extraction yields (14.8 and 12.0% for dried leaves and twigs, respectively) were obtained with 70% acetone, for both extraction procedures. Extracts were characterized for total phenolics content (TPC), total flavonoid content (TFC) and total proanthocyanidin content (TPrAC). Bioactive extracts with high TPC (526.4 mg GAE/g extract), TFC (198.4 mg CatE/g extract), and TPrAC (631.3 mg PycE/g extract) were obtained using maceration, a technically simple and low-energy process. The non-polar fraction of selected extracts was characterized using gas chromatography and time of flight mass spectrometry (GC-TOFMS). The main components detected were phytol, squalene, α-tocopherol, lupenone, and lupeol. The antioxidant activity of the extracts was characterized through DPPH and FRAP assays. Antimicrobial activity of the extracts against different bacteria was also determined. The highest DPPH and FRAP activities were obtained from dried twigs from Alcobaça (1068.3 mg TE/g extract and 9194.6 mmol Fe2+/g extract, respectively). Extracts from both leaves and twigs showed antimicrobial properties against Staphylococcus aureus, Staphylococcus epidermidis, methicillin resistant Staphylococcus aureus (MRSA), Enterococcus faecalis, Bacillus cereus, Streptococcus mutans, and Streptococcus mitis. The results obtained demonstrate the feasibility of recovering valuable components from these biomass fractions that may be further valorized for energy production in a biorefinery concept.

Impact of soaking and cooking treatments on the physicochemical and antioxidant properties of parboiled and non-parboiled rice (Oryza sativa L.).

The effects of soaking and cooking on the physicochemical properties and bioactive compounds of two parboiled and non-parboiled rice cultivars (BRRI-28 and Katari bhog) were investigated in this study. Total phenolic content (TPC) increased significantly (p ≤ 0.5) after soaking, while total flavonoid content (TFC) and proanthocyanidin content (PC) decreased significantly (p ≤ 0.5) compared to untreated rice samples. TPC increased by around 23% and 20% in parboiled BRRI 28 and Katari bhog rice extracts, respectively, due to the cooking process, while TFC and PC decreased significantly. DPPH radical scavenging increased whereas reducing power activity decreased after soaking and cooking in parboiled BRRI 28. After processing, the protein, starch, and amylose content of all samples decreased in the majority of cases. After being soaked, all samples L * and b * values increased as compared to raw rice samples. As a result, it can be concluded that the treatment of soaking and cooking of parboiled rice (BRRI-28) was suitable to improve the antioxidant properties as compared to non-parboiled rice.

Metabolomics and proteomics reveal the molecular basis of colour formation in the pericarp of Chinese wild rice (Zizania latifolia)

Chinese wild rice (Zizania latifolia) is rich in flavonoids and the characteristic colour of its pericarp is attributed to the flavonoids. In this study, the molecular basis of the colour change in the pericarp of Chinese wild rice was studied using metabolomics and proteomics. Whole seeds in three developmental stages (10, 20, and 30 days after flowering) were characterised based on phenolic contents, free amino acids (FAAs), and the expression level and activities of enzymes critical in flavonoid biosynthesis. The total phenolic and proanthocyanidin contents of Chinese wild rice increased gradually, whereas total flavonoid and FAA contents decreased during seed development. Metabolomic analysis revealed gradual upward trends for 57 flavonoids (sub classes 1, 3, and 10) related to colour change in the pericarp. Proteomic analysis showed that the phenylpropanoid biosynthesis metabolic pathway was enriched with differentially expressed proteins and was associated with flavonoid biosynthesis. Proteomic data suggested that leucoanthocyanidin reductase and WD40 repeat protein may be involved in flavonoid biosynthesis in Chinese wild rice, which was also verified by real-time quantitative PCR. Our results provide new insights into the understanding of the colour formation in the pericarp of Chinese wild rice.