Main Phenolic Compounds Research Articles

Optimization of microwave-assisted extraction using response surface methodology and HPLC-DAD phenolic compounds quantification from Hylocereus undatus peel and pulp cultivated in Tunisia

The present study aimed to optimize the microwave-assisted extraction process for both the peel and pulp of Hylocereus undatus (white dragon fruit) cultivated in Tunisia, using response surface methodology. Total phenolic content, total flavonoid content, FRAP (ferric reducing antioxidant power), and DPPH (1,1-diphenyl-2-picrylhydrazyl) antioxidant activities were optimized. A central composite design (CCD) was applied, considering three key variables: extraction time, extraction temperature, and liquid-to-solid ratio. The optimized extraction parameters for Hylocereus undatus peel and pulp were determined respectively (9.57 min, 42.20 °C and 27.79 mL/g) and (10.08 min, 40.84 °C and 31.52 mL/g). The main phenolic compounds identified in Hylocereus undatus peel and pulp extracts using HPLC-DAD were chlorogenic and caffeic acids and rutin, quercetin, luteolin-7-O-glucoside as flavonoids. Therefore, this research has revealed the potential of a sustainable and eco-friendly process hold promise a directional option and encouraging a circular economy approach for industrial production of antioxidant-rich Hylocereus undatus extracts.

Optimization of Microwave Assisted Extraction of Bioactive Compounds in Oregano and Lovage Ethanolic Extracts

Oregano and lovage contain a wide variety of bioactive compounds, but conventional extraction techniques usually generate small amounts of secondary metabolites. Thus, the extraction method and the recovery of these compounds represent a current challenge. The aim of this study was to optimize 3 microwave-assisted extraction (MAE) parameters, by response surface methodology (RSM), to obtain ethanolic bioactive extracts from oregano and lovage. The obtained extracts were assessed for their total phenolic content (TPC), antioxidant activity (AA), radical scavenging activity (I%), and antibacterial activity by determining the minimal inhibitory concentration (MIC) against Escherichia coli and Staphylococcus aureus. The ethanol concentration (X1: 40, 60 and 80%), microwave power (X2: 160; 480 and 800 W), and repetitions (X3: 1 to 10 times) were set as independent variables. The obtained models were validated with new experimental results, and confirmed for the 3 response parameters: TPC, AA, and I%. High-performance liquid chromatography (HPLC) was used to identify and quantify the main phenolic compounds in both optimum oregano and lovage extracts. The optimal extraction parameters were obtained with 49% ethanol, 160 W and 10 repetitions for oregano, whereas for lovage, 53% ethanol, 800 W power, and 10 extraction repetitions were optimal.

The Profile of Phenolic Compounds Identified in Pitaya Fruits, Health Effects, and Food Applications: An Integrative Review

Objective: This integrative review aimed to identify the phenolic compounds present in pitayas (dragon fruit). Methods: We employed a comprehensive search strategy, encompassing full-text articles published between 2013 and 2023 in Portuguese, English, and Spanish from databases indexed in ScienceDirect, Capes Periodics, Scielo, and PubMed. The study’s selection was guided by the question, “What are the main phenolic compounds found in pitaya fruits?”. Results: After screening 601 papers, 57 met the inclusion criteria. The identified phytochemicals have been associated with a range of health benefits, including antioxidant, anti-inflammatory, and anxiolytic properties. Additionally, they exhibit promising applications in the management of cancer, diabetes, and obesity. These 57 studies encompassed various genera, including Hylocereus, Selenicereus, and Stenocereus. Notably, Hylocereus undatus and Hylocereus polyrhizus emerged as the most extensively characterized species regarding polyphenol content. Analysis revealed that flavonoids, particularly kaempferol and rutin, were the predominant phenolic class within the pulp and peel of these fruits. Additionally, hydroxycinnamic and benzoic acid derivatives, especially chlorogenic acid, caffeic, protocatechuic, synaptic, and ellagic acid, were frequently reported. Furthermore, betalains, specifically betacyanins, were identified, contributing to the characteristic purplish-red color of the pitaya peel and pulp. These betalains hold significant potential as natural colorants in the food industry. Conclusion: Therefore, the different pitayas have promising sources for the extraction of pigments for incorporation in the food industry. We recommend further studies investigate their potential as nutraceuticals.

Processing of Angelica (Angelica sylvestris L.) into a functional jam with addition of carob and cinnamon extracts: Evaluation of sensorial, physicochemical, and nutritional characteristics and in vitro bioaccessibility of phenolics

AbstractA traditional Angelica jam has been produced from stems of Angelica sylvestris L. growing at the foot of Mount Uludag in Bursa for many years. The aim of this study was to develop new functional formulations of Angelica jam by adding carob and cinnamon extracts, and to evaluate the effect of jam processing and the extracts' addition on the sensory attributes, physicochemical and nutritional characteristics of Angelica jams as well as in vitro bioavailability of phenolics. The main physicochemical properties of the jams including total water‐soluble dry matter (Brix value), pH, invert sugar content, total dietary fiber content, and 5‐(hydroxymethyl) furfural (HMF) ranged between 71.80–72.70 °Bx, 3.65–3.91, 39.30%–49.60%, 0.70–0.90 g/100 g, and 91.00–105.50 mg/kg, respectively. The most abundant minerals were potassium (K), calcium (Ca), magnesium (Mg), phosphorus (P), and iron (Fe) within a concentration range of 80.49–388.67 mg/kg, 111.10–135.00 mg/kg, 24.00–43.28 mg/kg, 7.57–28.06 mg/kg, and 0.52–1.14 mg/kg, respectively. Sensory analysis revealed that general acceptability of Angelica jams in a 9‐point hedonic scale was above 7. The highest antioxidant capacity values of Angelica jam and its functional forms fortified with carob and cinnamon extracts were obtained as 96.68 ± 11.30 mg TE/100 g DM, 248.49 ± 17.78 mg TE/100 g DM, and 193.11 ± 16.06 mg TE/100 g DM, respectively, with the ABTS (2,2′‐azino‐bis‐3‐ethylbenzothiazoline‐6‐sulfonic acid) method. It was observed that the main phenolic compound of the jams was caffeic acid. Depending on the type of extract added into the formulations, trans‐cinnamic acid and gallic acid (GA) became predominant phenolics. Total antioxidant capacity (TAC) of Angelica sylvestris stem decreased by 72%–85% with the heat treatment applied during jam processing. While total phenolic content (TPC) and total antioxidant capacity (measured by the DPPH (1,1‐diphenyl‐2‐picrylhydrazyl) method) increased as a result of intestinal digestion of the jam, it was observed that bioaccessibility of most of the phenolic compounds decreased after intestinal digestion of the jams.

Inhibitory Effects of Fruit Powders on the Formation of Polycyclic Aromatic Hydrocarbons in Charcoal-Grilled Pork

Polycyclic aromatic hydrocarbons (PAHs), carcinogenic substances primarily formed through pyrolysis and oxidation of fat at high cooking temperatures, are commonly found at high levels in grilled meats. Reducing PAHs formation by incorporating natural antioxidants, such as through marination, has been demonstrated to be effective. However, the inhibitory effect of fresh phenolic-rich fruit powders on PAHs formation in charcoal-grilled meats remains unknown. To clarify the application of the fruit powders, 15 experimental groups were conducted. All pretreatment techniques (spraying, marinating, and mixing) were applied across all four freeze-dried fruit powders (lemon, guava, papaya, and mango). Each method was systematically tested with each fruit powder to evaluate its effect on inhibiting the formation of the four PAHs (BaA, CHR, BbF, and BaP) in charcoal-grilled pork belly and loin. Firstly, guava powder exhibited the highest phenolic content and antioxidant activity compared to the lemon, papaya, and mango powders (p < 0.05), among which the main phenolic compounds were ellagic acid, quercetin, and epigallocatechin gallate (EGCG). Further, marination of pork belly with guava powder exhibited the highest inhibition rate of PAHs (94.8%), followed by lemon (91.1%), papaya (89.8%), and mango (89.0%), with a statistically significant difference at p < 0.05. The reduction in estimated daily intake (EDI) and the increase in the margin of exposure (MOE) indicate that consuming grilled meat treated with these fruit powders poses no safety concerns and may potentially reduce health risks. Finally, the sensory evaluation showed that marinating with guava powder did not perceptibly affect the sensory attributes of the meat. Overall, this study provides a potent strategy for inhibiting the formation of PAHs in meat during charcoal grilling by incorporating fruit powder while preserving sensory qualities.

Biofunctionality of a new vinegar rich in anthocyanin from red-fleshed Niedzwetzky's apple: An ornamental plant.

In recent years, red-fleshed apple has attracted a lot of attention due to its pleasant appearance, taste, and being a valuable source of anthocyanins. Generally, different types of this apple are known as ornamental apple plants that are rarely found in various regions around the world like New Zealand, Kazakhstan, Kyrgyzstan, Australia,China, and Turkey. This study focused on the accumulation and changes of the bioactive and aroma-related volatile components at different production stages of a red-fleshed apple vinegar. The aim of this study is to produce an anthocyanin- and vitamin C-rich vinegar (NAV) from red-fleshed Niedzwetzky's apple for the first time. According to the results, in this vinegar, it wasdetermined high concentrations of total phenolic content (904.8mg-GAE/mL), total flavonoid content (0.25mg-EGCE/mL), vitamin C content (3024.3mg-AAE/mL), and 1,1-diphenyl-2-picrylhydrazyl (8.33mmol-TE/mL), as well as FRAP (13.57mmol-ISE/mL), respectively. Moreover, total anthocyanin content value was found to be 6.46mg/g. One of the components that provide the specified functional effect in this vinegar is chlorogenic acid, which constitutes the main phenolic compound, and the other one is cyanidin-3-glucoside, which is the major anthocyanin in this vinegar. The main volatile components associated with the aroma of vinegar are -acetic acid, -phenylacetic acid (5067.7µg/100mL), -phenethyl alcohol (3096.1µg/100mL), and -nonanoic acid (2939.0µg/100mL) compounds. Consequently, it is recommended to expand the range of Niedzwetzky's apples in the production and consumption of food products such as functional vinegar. Thus, a new vinegar with high functional properties will be introduced to the worldwide food industry. PRACTICAL APPLICATION: In this study, vinegar was produced from the small and dark-red-flesh-colored fruits of Niedzwetzky's apple tree, which is known in a small part of the world and is generally used as an ornamental plant due to its red-pink flowers. It has been determined that the produced vinegar has high bioavailability due to the apples with red inner flesh and high anthocyanin content and has a desirable aromatic content. Thus, a food product with high functional quality and desirable aroma, accessible to consumers all over the world, has been produced from a little-known fruit.

Fermented plant-based beverage supplemented with uvaia (Eugenia pyriformis) pulp: an innovative and pioneering approach to diversify plant-based diet product market

Over the years, there has been an increase in demand for plant-based foods as alternatives. In line with this, this work explores the production and in vitro digestion of a fermented plant-based beverage (FPBB) produced with pea and rice proteins and 0% (FPBB-C), 5% (FPBB-5), and 10% (FPBB-10) uvaia pulp through lactic fermentation with Lacticaseibacillus rhamnosus GG. The in vitro gastrointestinal digestion process was conducted to assess the bioaccessibility of L. rhamnosus GG, total phenolic content (TPC), and antioxidant activity before and after simulating the gastrointestinal conditions. After 48 h of digestion, highly viable L. rhamnosus GG cells remained throughout the gastrointestinal system. FPBB-C (106.89%) and FPBB-5 (109.38%) exhibited higher survival rates than FPBB-10 (102.20%), indicating that these beverages have a higher prebiotic action potential. Compared with the non-digested samples, after 48 h of digestion, all samples exhibited a significant increase in TPC. The same behavior occurs for the antioxidant activity of FPBB-C, FPBB-5, and FPBB-10 by DPPH (4.06, 3.96, and 8.44 mg TEAC mL−1), ABTS (10.28, 11.06, 11.97 mg TEAC mL−1), and FRAP method (917.02, 863.87, and 1983.23 mg TEAC mL−1). Thirteen compounds were identified and quantified in uvaia pulp by HPLC-DAD-ESI-MS, particularly epigallocatechin gallate, quercetin-3-rhamnose, and quercetin-3-glucoside. Isorhamnetin was the main phenolic compound detected in the colon, assumably due to the conversion of quercetin-3-glucoside by the probiotic cells. In conclusion, as all counts were above 9 log CFU g−1, the FPBB formulations containing pea, rice protein, and uvaia pulp become a promising vehicle for carrying L. rhamnosus GG.

Extract of Araçá-Boi and Its Major Phenolic Compound, Trans-Cinnamic Acid, Reduce Viability and Inhibit Migration of Human Metastatic Melanoma Cells.

Cutaneous melanoma is an aggressive type of skin cancer that is recognized for its high metastatic potential and the challenges it presents in its treatment. There has been increasing interest in plant extracts and their potential applications in melanoma. The present study aimed to investigate the content of individual phenolic compounds in araçá-boi extract, evaluate their antioxidant activity, and explore their effects on cell viability, migration properties, oxidative stress levels, and protein expression in the human metastatic melanoma cell line SK-MEL-28. HPLC-DAD analysis identified 11 phenolic compounds in the araçá-boi extract. Trans-cinnamic acid was the main phenolic compound identified; therefore, it was used alone to verify its contribution to antitumor activities. SK-MEL-28 melanoma cells were treated for 24 h with different concentrations of araçá-boi extract and trans-cinnamic acid (200, 400, 600, 800, and 1600 µg/mL). Both the araçá-boi extract and trans-cinnamic acid reduced cell viability, cell migration, and oxidative stress in melanoma cells. Additionally, they modulate proteins involved in apoptosis and inflammation. These findings suggest the therapeutic potential of araçá-boi extract and its phenolic compounds in the context of melanoma, especially in strategies focused on preventing metastasis. Additional studies, such as the analysis of specific signaling pathways, would be valuable in confirming and expanding these observations.

Aromatic Herbs of the Lamiaceae Family as Functional Ingredients in Wheat Tortilla

The rationale for this research is the investigation of the potential health benefits as well as the antibacterial and antifungal properties of selected aromatic plants from the Lamiaceae family, which may lead to the development of improved functional foods. The present study investigated the effects of incorporating dried aromatic plants Thymus vulgaris, Thymus serpyllum, Thymus × citriodorus, Origanum vulgare and Rosmarinus officinalis at a concentration of 1% in refined wheat flour and wholemeal flour on the production of functional tortillas. Sensory analysis was employed to identify the optimal 1% addition, with the objective of achieving a favorable flavor and aroma profile. It was hypothesized that this addition would affect water activity, moisture, texture, color, antioxidant content and phenolic content, thereby enhancing the tortillas as a source of bioactive compounds. The results indicated that the type of flour used had a significant impact on the water activity of the tortillas, with wholemeal flour resulting in higher water activity than refined flour. The water activity ranged between 0.735 and 0.821, while the water content remained relatively stable. The water activity in whole-grain tortillas was significantly higher than that of refined flour tortillas, with a value exceeding 0.8, which makes them susceptible to mold growth and the production of mycotoxins. The sensory evaluations indicated that the enriched refined flour tortillas with common thyme (Thymus vulgaris), lemon thyme (Thymus × citriodorus) and rosemary (Rosmarinus officinalis) were rated highly; a similar result was observed for the whole-grain tortillas enriched with wild thyme (Thymus serpyllum) and lemon thyme. The whole-grain tortillas with rosemary were rated the highest of all the tortillas. The addition of aromatic plants increased the phenolic content and the antioxidant potential, depending on the flour type and the plant used. The addition of wild thyme and rosemary resulted in a significant increase in the phenolic content of wheat tortillas, while all enriched whole-grain tortillas exhibited a higher phenolic content than the control samples. The highest phenolic content in whole-grain tortillas was found in those fortified with rosemary, oregano and wild thyme. The highest antioxidant content was recorded in tortillas prepared with rosemary, irrespective of whether the flour used was refined or wholemeal. Fourteen phenolic compounds were tentatively identified in aromatic plants tested. The main phenolic compounds in Origanum vulgare were flavonoids. Rosmarinic acid was the dominant phenolic compound in rosemary and all thyme species, reaching the highest level in rosemary. Such high levels of rosmarinic acid may be responsible for the high antioxidant and total phenolic contents observed in rosemary extracts and also in tortillas when this plant is included in the recipe. The results of this study indicate that selected aromatic plants, particularly rosemary, have the potential to be utilized as functional ingredients in bakery products. By incorporating dried aromatic plants from the Lamiaceae family into wheat flour tortillas, food manufacturers can create products that not only taste better but also provide added health benefits. The use of selected herbs can improve the nutritional profile of tortillas by increasing antioxidant properties and, due to the properties of herbs, extend the shelf life of the product.

Araucaria angustifolia and Picrasma crenata extracts as potential agents for the control of phytopathogenic fungi of agricultural interest

To expand knowledge about native species in southern Brazil, different types of extracts from the thin vinaceous bark of A. angustifolia and fragments of branches of P. crenata were evaluated. These were crushed and kept for fifteen days in contact with hydroalcoholic solutions at 70 % v/v and ethanolic (96 % v/v), seven days in the cold aqueous extract, and through the decoction process for 10 min. Afterward, they were evaluated at concentrations of 1.0 %, 2.5 %, 5.0 %, 10.0 %, and 20.0 % v/v on the mycelial development of the phytopathogenic fungi Colletotrichum gloeosporioides, Botrytis cinerea, and Sclerotinia sclerotiorum. The levels of phenolic compounds and total flavonoids were evaluated, and the alcoholic extracts of A. angustifolia had the highest total phenolic content. The main phenolic compounds identified in the P. crenata extract were resveratrol, followed by herperidin, rutin, ferulic acid, and kaempferol, and the main chemical compounds identified in the extracts of A. angustifolia were quercetin, rutin, ferulic acid, kaempferol, and gallic acid. A. angustifolia extracts and P. crenata, during the decoction, were more effective in controlling the phytopathogens C. gloeosporioides and B. cinerea from a concentration of 5 % v/v. The fungus S. sclerotiorum was moderately inhibited in hydroalcoholic extracts at 70 % v/v of P. crenata and A. angustifolia at 1.0 % and 2.5 % v/v concentrations. Effectively controlling these phytopathogenic fungi of agricultural importance confers importance on the conservation of these native species of socio-biodiversity in the Atlantic Forest in southern Brazil.

Potential skin anti-aging effects of main phenolic compounds, tremulacin and tremuloidin from Salix chaenomeloides leaves on TNF-α-stimulated human dermal fibroblasts

The genus Salix spp. has long been recognized as a healing herb for its use in treating fever, inflammation, and pain relief, as well as a food source for its nutritional value. In this study, we aimed to explore the potential bioactive natural products in the leaves of Salix chaenomeloides, commonly known as Korean pussy willow, for their protective effects against skin damage, including aging. Utilizing LC/MS-guided chemical analysis of the ethanol extract of S. chaenomeloides leaves, with a focus on major compounds, we successfully isolated two main phenolic compounds, tremulacin (1) and tremuloidin (2). Subsequently, we investigated the protective effects of tremulacin (1) and tremuloidin (2) in TNF-α-stimulated human dermal fibroblasts (HDFs). The results revealed that both tremulacin (1) and tremuloidin (2) inhibited TNF-α-stimulation-induced ROS, suppressed matrix metalloproteinase-1 (MMP-1) expression, and enhanced collagen secretion. This implies that both tremulacin (1) and tremuloidin (2) hold promise as preventive agents against photoaging-induced skin aging. Furthermore, we assessed the activity of mitogen-activated protein kinases (MAPKs), cyclooxygenase-2 (COX-2), and heme oxygenase 1 (HO-1) to elucidate the mechanism of photoaging inhibition by tremuloidin (2), which exhibited superior efficacy. We found that tremuloidin (2) inhibited ERK and p38 phosphorylation and notably suppressed COX-2 expression while significantly upregulating HO-1 expression. These findings suggest potent anti-inflammatory and antioxidant properties of tremuloidin (2), positioning it as a potential candidate for combating photoaging-induced skin aging.

Binding affinity screening of polyphenolic compounds in Stachys affinis extract (SAE) for their potential antioxidant and anti-inflammatory effects

Free radical is a marker in various inflammatory diseases. The antioxidant effect protects us from this damage, which also plays an essential role in preventing inflammation. Inflammation protects the body from biological stimuli, and pro-inflammatory mediators are negatively affected in the immune system. Inflammation caused by LPS is an endotoxin found in the outer membrane of Gram-negative bacteria, which induces immune cells to produce inflammatory cytokines such as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase. Based on this, the antioxidant and anti-inflammatory effects of plant extracts were investigated. First, the main phenolic compounds for the five peaks obtained from Stachys affinis extract (SAE) were identified. The antioxidant effect of each phenolic compound was confirmed through HPLC analysis before and after the competitive binding reaction between DPPH and the extract. Afterward, the anti-inflammatory effect of each phenolic compound was confirmed through competitive binding between COX2 and the extract in HPLC analysis. Lastly, the anti-inflammatory effect of SAE was confirmed through in vitro experiments and also confirmed in terms of structural binding through molecular docking. This study confirmed that phenolic compounds in SAE extract have potential antioxidant and anti-inflammatory effects, and may provide information for primary screening of medicinal plants.

Purification, Characterization, and Anti-Inflammatory Potential of Free and Bound Polyphenols Extracted from Rosa roxburghii Tratt Pomace.

Rosa roxburghii Tratt pomace (RRTP), an underutilized byproduct, is rich in polyphenol compounds. This study aimed to further explore the purification, characterization, anti-inflammatory activities, and underlying molecular mechanisms of free polyphenols (RRTP-FP) and bound polyphenols (RRTP-BP) from RRTP. The results indicated that AB-8 macroporous resin emerged as the preferred choice for subsequent separation and purification. The purities of purified RRTP-FP (P-RRTP-FP) and purified RRTP-BP (P-RRTP-BP) increased by 103.34% and 66.01%, respectively. Quantitative analysis identified epigallocatechin, epicatechin, and ellagic acid as the main phenolic compounds in P-RRTP-FP. In P-RRTP-BP, the primary phenolic compounds were ellagic acid, epicatechin, and gallic acid. In vitro antioxidant assays demonstrated the superior DPPH and ABTS radical scavenging activities of P-RRTP-FP and P-RRTP-BP compared to vitamin C. Treatment with P-RRTP-FP and P-RRTP-BP reduced nitric oxide (NO) and reactive oxygen species (ROS) production, mitigated the decline in cellular membrane potential, and significantly downregulated the mRNA expression of pro-inflammatory cytokines and inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Additionally, P-RRTP-FP and P-RRTP-BP inhibited the phosphorylation of pertinent proteins in the nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. This finding suggests potential utility of RRTP-derived polyphenols as anti-inflammatory agents for managing severe inflammatory conditions.

Protective effect and antioxidative efficacy of Moringa stenopetala leaf extract in BV-2 microglial cell

Moringa stenopetala is often consumed as food and used in folkloric medicine for the management of several diseases including neurodegenerative diseases. This study investigated the protective effect and antioxidant efficacy of aqueous extract of Moringa stenopetala in BV-2 microglial cells. Aqueous extracts of M. stenopetala were prepared, lyophilized and reconstituted in 0.5% dimethylsulphoxide (DMSO). Cells were treated with M. stenopetala extracts (0.1–100 µg/ml) for cell viability assay and nitric oxide (NO) production tests. However, M. stenopetala extract (50 µg/ml) was used in the treatment of cells for the determination of protein carbonyl content and reactive oxygen species (ROS) level. Incubation of BV-2 microglia cell with M. stenopetala extract maintained cell viability, diminished NO and ROS levels, and reduced protein carbonyl contents. Chlorogenic acid, rutin, kaempferol and quercetin derivatives were the main phenolic compounds identified in M. stenopetala leaf extract. In conclusion, this study suggests that M. stenopetala extract is rich in antioxidant and contains bioactive neuroprotective agents.

Amelioration activity of the high bioaccessible chrysanthemum (Gongju) phenolics on alcohol-induced oxidative injury in AML-12 cells

The main bioavailable phenolics from of Gongju (GJ) and their mechanism for hepato-protection remain unclear. To select the GJ phenolics with high bioavailability, chrysanthemum digestion and Caco-2 cells were used and their hepato-protective potential were examined by using AML-12 cells. The digestive recovery and small intestinal transit rate of the main phenolic compounds ranged from 28.52 to 69.53% and 6.57% ∼ 15.50%, respectively. Among them, chlorogenic acid, 3,5-dicaffeoylquinic acid, and 1,5-dicaffeoylquinic acid, showed higher small intestinal transit rates and digestive recoveries. Furthermore, we found that by increasing intracellular Catalase (CAT) and Superoxide dismutase (SOD) viability and lowering Malondialdehyde (MDA) level (P < 0.05), 3,5-dicaffeoylquinic acid significantly mitigated the oxidative damage of AML-12 liver cells more than the other two phenolics. Our results demonstrated that 3,5-dicaffeoylquninic acid was the primary phenolic compounds in GJ that effectively reduced liver damage, providing a theoretical basis for the development of GJ as a potentially useful resource for hepatoprotective diet.

Modifications in gene expression and phenolic compounds content by methyl jasmonate and fungal elicitors in Ficus carica. Cv. Siah hairy root cultures

BackgroundOne of the most effective strategies to increase phytochemicals production in plant cultures is elicitation. In the present study, we studied the effect of abiotic and biotic elicitors on the growth, key biosynthetic genes expression, antioxidant capacity, and phenolic compounds content in Rhizobium (Agrobacterium) rhizogenes-induced hairy roots cultures of Ficus carica cv. Siah.MethodsThe elicitors included methyl jasmonate (MeJA) as abiotic elicitor, culture filtrate and cell extract of fungus Piriformospora indica as biotic elicitors were prepared to use. The cultures of F. carica hairy roots were exposed to elicitores at different time points. After elicitation treatments, hairy roots were collected, and evaluated for growth index, total phenolic (TPC) and flavonoids (TFC) content, antioxidant activity (2,2-diphenyl-1-picrylhydrazyl, DPPH and ferric ion reducing antioxidant power, FRAP assays), expression level of key phenolic/flavonoid biosynthesis genes, and high-performance liquid chromatography (HPLC) analysis of some main phenolic compounds in comparison to control.ResultsElicitation positively or negatively affected the growth, content of phenolic/flavonoid compounds and DPPH and FRAP antioxidant activities of hairy roots cultures in depending of elicitor concentration and exposure time. The maximum expression level of chalcone synthase (CHS: 55.1), flavonoid 3′-hydroxylase (F3’H: 34.33) genes and transcription factors MYB3 (32.22), Basic helix-loop-helix (bHLH: 45.73) was induced by MeJA elicitation, whereas the maximum expression level of phenylalanine ammonia-lyase (PAL: 26.72) and UDP-glucose flavonoid 3-O-glucosyltransferase (UFGT: 27.57) genes was obtained after P. indica culture filtrate elicitation. The P. indica elicitation also caused greatest increase in the content of gallic acid (5848 µg/g), caffeic acid (508.2 µg/g), rutin (43.5 µg/g), quercetin (341 µg/g), and apigenin (1167 µg/g) phenolic compounds.ConclusionsThis study support that elicitation of F. carica cv. Siah hairy roots can be considered as an effective biotechnological method for improved phenolic/flavonoid compounds production, and of course this approach requires further research.

Valuable Nutrients, Aroma Profile, and Functional Bioactives Extracted by Eco-Friendly Extraction Techniques from Wild Olive Fruits (Olea europaea L. var. sylvestris)

Wild olive tree, or oleaster (var. sylvestris), native to the Mediterranean region, is considered a traditional source of healthy food. Wild olive fruit (WOF) exhibits several biological properties associated with its chemical composition. Although Greece has important olive genetic resources, including oleaster populations, limited information is available on the chemical characterization of WOF. Therefore, the present investigation was undertaken to study the nutritional, bioactive (phenolics, tocopherols, and pigments), volatile profile, and antioxidant properties of WOF collected from Greece. Moreover, eco-friendly processes, including ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and accelerated solvent extraction (ASE), were applied to obtain oleuropein-rich extracts from WOF. Evaluation of phenolic composition in WOF extracts was carried out by LC-DAD-ESI-MS, while antioxidant activity was evaluated by applying DPPH, ABTS, and FRAP methods. Our outcomes show that Greek WOF is rich in oleic acid (71.55%), total phenolics (64.89 mg GAE/g dw), tocopherols (107.05 mg/kg dw), and carotenoids (85.90 mg/kg dw). Oleuropein (72.03 mg/g dw) was the main phenolic compound in the WOF extracts. Also, the WOF was characterized by an increased level of volatile compounds, mainly terpenoids (46.73%). UAE was more efficient than MAE and ASE for recovering oleuropein-rich extracts with high antioxidant activity. These results emphasized the high potential of WOF as an alternative bioactive ingredient for use in the food industry.

Health-Related Composition and Bioactivity of an Agave Sap/Prickly Pear Juice Beverage

In this study, a beverage made from a combination of Agave sap (AS) and prickly pear juice (PPJ) was analyzed for its nutrients and bioactive and potentially health-promoting compounds. The beverage was evaluated for its ability to act as an antioxidant, regulate glycemic properties, and undergo gut bacterial fermentation in vitro. The major mono- and oligosaccharides present in the beverage were galacturonic acid (217.74 ± 13.46 mg/100 mL), rhamnose (227.00 ± 1.58 mg/100 mL), and fructose (158.16 ± 8.86 mg/mL). The main phenolic compounds identified were protocatechuic acid (440.31 ± 3.06 mg/100 mL) and catechin (359.72 ± 7.56 mg/100 mL). It was observed that the beverage had a low glycemic index (&lt;40) and could inhibit digestive carbohydrases. The combination of ingredients also helped to reduce gas production during AS fermentation from 56.77 cm3 to 15.67 cm3. The major SCFAs produced during fermentation were butyrate, acetate, and propionate, with valerate being produced only during the late fermentation of the AS. This beverage is rich in bioactive compounds, such as polyphenols and dietary fiber, which will bring health benefits when consumed.

Antibacterial activity of avocado extract (Persea americana Mill.) against aminoglycoside-resistant Klebsiella pneumoniae strains

Klebsiella pneumoniae is an important etiological agent of nosocomial infections. This study focuses on the antibacterial activity of Persea Americana extract against K. pneumoniae strains containing aminoglycoside genes. Broth microdilution technique was used to examine the antibacterial activity of P. americana extract on K. pneumoniae isolates. The phenolic components of its leaves were analysed by the HPLC-DAD system. The binding potential of the major phytochemical component of the extract, chlorogenic acid, to the KsgA was investigated by molecular docking. The stability of the resulting enzyme-ligand complexes was also assessed through molecular dynamics simulation. The result obtained showed that P. americana extract had antibacterial activity on aminoglycoside resistant strains. The binding potential of chlorogenic acid (main phenolic compound) to KsgA was found to be higher than the binding of gentamicin. Since chlorogenic acid had lower binding energy and formed higher number of H-bonding as well as other interactions in the docking analysis. The higher binding potential of the major component with the enzyme that was involved in resistance development against aminoglycoside indicated its possible role in overturning the condition. Moreover, the molecular dynamics simulation study revealed that chlorogenic acid formed a complex with relatively higher stability. The higher binding potential of the major component with higher stability implied that the computational results confirmed the experimental findings.

Mediterranean Wild Pear Fruits as a Neglected but Valuable Source of Phenolic Compounds

The genus Pyrus has a long history in Sardinia (Italy), where two wild pear species (P. spinosa Forssk. and P. pyraster (L.) Burgsd.) and Pyrus communis L. cultivars are extensively distributed. Even if neglected, these taxa represent well-adapted key resources for redesigning sustainable farming systems. This report aims at shedding light on the phenolic fingerprint and antioxidant properties of wild pear fruits and comparing their traits with those of the studied pear cultivar germplasm (PCG). Fruits of wild pear species were collected, and flesh, peel, and core subsamples were analyzed. Moreover, available data from previous research on PCG were analyzed. The contents of total phenolics (TotP), total flavonoids (TotF), and condensed tannins (CT), as well as the antioxidant capacity, were similar in the flesh of the two wild species. However, P. spinosa had significantly higher values of TotP (89 g GAE kg−1 DM) and CT (33 g DE kg−1 DM) in the peel. Eleven individual phenolic compounds were identified and quantified in the fruit flesh, 14 in both peel and core. For both wild species, arbutin and chlorogenic acid were the main phenolic compounds, followed by the quercetin glycosides. Comparing the antioxidant capacity and TotF fruit flesh values of wild pears with those of PCG, the latter resulted up to 15-fold lower. The wild types showed unique metabolite profiles. Results support novel insights on the phytochemicals of wild pear fruits.