Their Total Phenolic Content Research Articles

Antioxidant Activity and Total Phenolic Content of Underutilized Edible Tree Species of the Philippines

Recently, neglected and underutilized species (NUS) have deservedly come to the forefront of scientific interest because they can contribute to the human nutrition, due to the content of bioactive substances such as antioxidants. Despite the great diversity and rich tradition in the use of Philippine NUS, the nutritional properties of many edible plants remain unexplored. The main objective of this study was to evaluate various parts of eleven NUS fruits and vegetables traditionally consumed in the Philippines, namely Allaeanthus luzonicus, Canarium ovatum, Dillenia philippinensis, Ficus pseudopalma, Flacourtia indica, Flacourtia inermis, Garcinia intermedia, Heliotropium arboreum, Posoqueria latifolia, Stelechocarpus burahol, and Sterculia quadrifida for their total phenolic content (TPC) and in vitro antioxidant activity (DPPH and ORAC assays). Inflorescence of A. luzonicus (DPPH IC50 = 91.0 μg/mL, ORAC IC50 = 37.9 μg/mL) and fruit of S. burahol (DPPH IC50 = 253.7 μg/mL, ORAC IC50 = 32.2 μg/mL) showed the strongest antioxidant activity in both assays. These two species also had the highest TPC (202.1 and 133.0 µg GAE/mg extract, respectively). For all samples tested, a strong correlation was found between TPC and antioxidant activity. Based on our results, A. luzonicus and S. burahol have promising potential as novel antioxidant rich food.

Exploring the chemical composition and biological effects of four Salvia hybrids: an innovative perspective on functional yields

AbstractGenus Salvia is considered one of the largest genera of family Lamiaceae with many recorded species and hybrids of valuable biological importance. This study involved the phytochemical characterization of four Salvia hybrids (KNM23 (S. fructicosa × S. officinalis), KNM101 (S. aramiensis × S. officinalis), KNM5 (S. aramiensis × S. officinalis) and KNM12 (S. fructicosa × S. officinalis)) through measuring their total phenolic content (TPC) and total flavonoid content (TFC) together with profiling through UPLC/MSn analysis followed by investigation of their antioxidant activities and enzyme inhibitory potential through different techniques. Hybrid KNM23 presented significantly high concentration of both phenolic and flavonoid, displaying a TPC of 92.10 mg GAE/g and a TFC of 50.85 mg RE/g. The UPLC/MSn profiling resulted in the tentative identification of one hundred eighty components from different phytochemical classes mainly flavonoids, phenolic acids, phenyl propanoids, tannins and many others. The antioxidant assay showed that hybrid KNM23, a hybrid of S. fruticosa and S. officinalis, exhibited the highest antioxidant activity in the DPPH, ABTS, and PBD assays, measuring 436.38 mmol TE/g, 543.65 mmol TE/g, and 3.20 mmol TE/g, respectively. KNM23 and KNM12 showed no inhibition of AChE and α‐glucosidase. However, KMN12 demonstrated highest BChE and tyrosinase 2.57 mg GALAE/g and 12.91 mg KAE/g, respectively. Our results suggest that the Salvia hybrids can be considered as natural sources of bioactive compounds in the development of health‐promoting applications.

Comparative assessment of antioxidant activity in red apricot (Prunus armeniaca L.) and Fig fruits (Ficus carica L.) cultivated in Nakhchivan AR, Azerbaijan

Red apricot (Prunus spp.) and Black Fig (Ficus carica L.) are two of the most commonly grown summer fruits in the Nakhchivan region. In this preliminary study, ethanol fruit extracts were compared based on their total phenolic content (TPC) and antioxidant properties. According to the Folin-Ciocalteu method, the TPC was found to be 176.20 mg GAE/100 g in red apricot and 45.30 mg GAE/100 g in fig. Their antioxidant capacities were assessed using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The scavenging activity, identified as the concentration of ethanol extract needed to scavenge half of the radicals (SC50), was determined to be 3.52 mg/mL for red apricot and 6.46 mg/mL for fig. Based on these two biological activity assays, red apricot exhibited higher phenolic composition and radical scavenging activity. However, further studies are required to understand whether these differences are attributed to secondary metabolites in these fruits.

Wounding Citrus Peel By-Products as Abiotic Stress to Induce the Synthesis of Phenolic Compounds?

Wounding stress stimulates secondary metabolism and induces the phytochemical accumulation of fresh-cut fruit and vegetables. This research aims to study the biosynthesis of secondary metabolites in citrus peel by-products after different wounding intensities. Orange, grapefruit, and lemon peels were cut into rectangular shapes of 8.5 × 2 cm (CTRL), 1 × 1 cm dices (D), and 0.25 cm grates (G). Samples were stored at 15 °C and 65% relative humidity. Their total phenolic content (TPC), total antioxidant capacity (TAC), and individual organic and phenolic compounds were analyzed after 0, 4, 8, 24, 28, and 36 h. The results showed that the metabolite content decreased with the incubation time, so it is recommended to sample by-products between the first 8 h to achieve the maximum content. Grating, the most severe abiotic stress, was not a suitable technique to induce the synthesis of biocompounds because it allowed the full recovery of flavedo, but partial of albedo. However, it was different for CTRL and D, whose TPCs were ~170 and ~200%, ~98 and ~78%, and ~8 and ~36% higher for orange, grapefruit, and lemon, respectively, compared to G. A principal component analysis confirmed differences between the fruit species and cutting shapes combining all factors. Wounding citrus peels induces the accumulation of phytochemical compounds, but the layer of peel recovered in the cut is crucial in the concentration of phytochemicals extracted. It could be an innovative tool to revalorize these inedible parts of citrus, but further research is still needed.

Extraction of Antioxidants from Brown Macroalgae Fucus spiralis.

In this study, different extraction methods and conditions were used for the extraction of antioxidants from brown macroalgae Fucus spiralis. The extraction methodologies used were ultrasound-assisted extraction (ultrasonic bath and ultrasonic probe), extraction with a vortex, extraction with an Ultra-Turrax® homogenizer, and high-pressure-assisted extraction. The extracts were analyzed for their total phenolic content (TPC) and their antioxidant activity, and evaluated through the 2,2-difenil-1-picrilhidrazil (DPPH) free radical scavenging method and ferric reducing antioxidant power (FRAP) assay. Ultrasonic probe-assisted extraction yielded the highest values of TPC (94.78-474.16 mg gallic acid equivalents/g extract). Regarding the antioxidant activity, vortex-assisted extraction gave the best DPPH results (IC50 1.89-16 µg/mL), while the highest FRAP results were obtained using the Ultra-Turrax® homogenizer (502.16-1188.81 μmol ascorbic acid equivalents/g extract). For each extraction method, response surface methodology was used to analyze the influence of the experimental conditions "extraction time" (t), "biomass/solvent ratio" (R), "solvent" (S, water % in water/ethanol mixture), and "pressure" (P) on TPC, DPPH, and FRAP of the F. spiralis extracts. In general, higher TPC content and higher antioxidant capacity (lower IC50 and higher FRAP) were obtained with higher R, t, and P, and lower S (higher ethanol %). The model regarding the combined effects of independent variables t, R, and S on the FRAP response values for vortex-assisted extractions best fitted the experimental data (R2 0.957), with optimal extraction conditions of t = 300 s, R = 50 g, and S = 25%.

The innovative extraction and purification process of insoluble polyphenols from Paeonia ostii roots: Optimum study and in vitro activities

The oil tree peony (Paeonia ostii) is widely cultivated for their high value seed oil, and its roots also have high medicinal value, but they are often discarded and wasted as by-products. In this study, a set of steam explosion (SE) and ultrasound (US)-assisted extraction/purification methods of insoluble bound phenols (IPs) from oil peony roots (PR) were explored and developed. The IPs were obtained through SE pre-treatment (120 °C, 15 min) and US-assisted alkaline extraction (0.25 W/cm2, 4 h and 4 M NaOH). Their total phenolic content (TPC) significantly increased from 112.26 mg gallic acid/g dry weight (mg GAE/g dw) with traditional method to 185.59 mg GAE/g dw. Subsequently, the IPs were purified into PIPs using LX-83 resin. The optimized purification conditions were pH = 4, 3.0 mg GAE/mL of IPs, 0.25 W/cm2 adsorption for 120 min, as well as 60 % ethanol desorption solution, and 0.25 W/cm2 desorption for 30 min. The TPC of the PIPs increased to 254.74 mg GAE/g dw. Notably, typical compounds in IPs and PIPs were identified and quantified by HPLC-MS and their antioxidant and anti-tyrosinase activities were also evaluated by chronometry. The results showed that paeoniflorin and benzoyl-paeoniflorin increased by about 10-fold in the PIPs. Additionally, they demonstrated superior antioxidant and tyrosinase inhibitory activities compared to IPs. Therefore, the innovative extraction and purification process greatly improved the yield of bound phenols and recovered paeoniflorin from non-medicinal PR. The process may also provide a reference for the in-depth development of medicinal PR, ultimately achieving more efficient PR development and utilization.

Extraction of macroalgae phenolic compounds for cosmetic application using eutectic solvents

Cosmetic industry remains a major focus of economic development in the 21st century, while consumer's demand for sustainability drives the search for new active natural ingredients and the development of green extractions techniques. The aim of this work is to obtain antioxidant-enriched extracts from two seaweeds found on the Portuguese shore, Sargassum muticum and Gelidium corneum using natural deep eutectic solvents (NADES) to be used in cosmetic formulations. Extracts were obtained by maceration of powdered seaweeds with aqueous solutions (25 % (v/v) in water) of different NADES, L-lactic acid: fructose (5:1), L-lactic acid: glucose (5:1) and L-lactic acid: sodium acetate (7:1). The resulting extracts were evaluated regarding their total phenolic content (TPC) using the Folin-Ciocalteu method and antioxidant capacity by the DPPH and FRAP assays. L-lactic acid: fructose (5:1) NADES yielded Sargassum muticum extracts with the highest phenolic content (2099 mg GAE/L) and the highest antioxidant activities (DPPH reduction of 27 %, FRAP 30 μM FeSO4). Antimicrobial activity of the extracts over three microorganisms of the skin microbiota, the bacteria Staphylococcus epidermidis and Cutibacterium acnes and the fungus Malassezia furfur, revealed no relevant antimicrobial effect, meaning that extracts did not affect the skin microbiota homeostasis. The extract with the highest cosmeceutical interest, S. muticum extract prepared using L-lactic acid: fructose (7:1), was incorporated into a topical O/W emulsion. Physical and rheology data of the cosmetic formulation ensure its quality and safety. Finally, compatibility, acceptability and antioxidant efficacy were evaluated in vivo, in human volunteers. The results show that NADES are a promising replacement of conventional solvents in the extraction of antioxidants from biomass and their use in topical formulations is safe.

Salvia mirzayanii and Salvia hypoleuca Essential Oils: Chemical Composition, Alpha-Glucosidase Inhibitory, and Synergistic Effects of Selected Components

Background: Salvia is one of the most important genera belonging to the Lamiaceae family that has been used in various applications in folk medicine and the pharmaceutical and food industries. Objectives: This study investigated the chemical composition, antioxidant activity, and α-glucosidase inhibitory activity of Salvia mirzayanii Rech. f. and Esfand. and Salvia hypoleuca Benth. essential oils (EOs). Additionally, the enzyme inhibitory activity of the mixture of compounds was evaluated to find whether the synergistic effect is responsible for the desired activity or not. Methods: The constituents of S. mirzayanii and S. hypoleuca EOs collected from Fars and Alborz provinces, Iran, were determined using gas chromatography-mass spectroscopy (GC-MS) analysis. They were evaluated for their α-glucosidase inhibitory activity by the determination of para-nitrophenol (pNP), derived from the enzymatic degradation of para-nitrophenol-D-glucopyranoside (pNPG) as the substrate. The activity of the selected components was also tested. Moreover, the antioxidant activity of EOs was evaluated based on the radical scavenging capability (2,2-Diphenyl-1-picrylhydrazyl [DPPH]) assay, and their total phenolic content (TPC) was determined using the Folin-Ciocalteu method in terms of gallic acid equivalent (GAE). Results: In total, 66 compounds were detected in the S. mirzayanii and S. hypoleuca EOs. The results showed that S. mirzayanii EO had more potent antioxidant activity (half-maximal inhibitory concentration [IC50] = 0.77 ± 0.00 mg/mL), higher TPC (78.26 ± 1.26 mg GAE/g EO), and a greater inhibitory effect toward α-glucosidase (IC50 = 55.15 ± 1.60 mg/mL) than S. hypoleuca EO. Furthermore, caryophyllene oxide (IC50 = 19.94 ± 0.26 mg/mL), α-pinene (IC50 = 17.59 ± 0.19 mg/mL), and linalool (IC50 = 38.00 ± 0.22 mg/mL) showed high levels of α-glucosidase inhibitory activity among the major constituents. In addition, the combination of linalool: 1,8-cineole: α-terpineol (40: 35: 25) inhibited this enzyme synergistically (combination index [CI] < 1). Conclusions: The findings indicated that S. mirzayanii EO had a high potential for developing efficient anti-type 2 diabetes agents.

Assessment of Antioxidant and Antibacterial Potential of Phenolic Extracts from Post-Distillation Solid Residues of Oregano, Rosemary, Sage, Lemon Balm, and Spearmint

Medicinal and aromatic plants (MAPs) are potential sources of natural polyphenols. Solid residues (SRs) from the essential oil (EO) industry are produced in significant volumes and may be used as natural sources of bioactive compounds. Therefore, this work was designed to examine the antioxidant and antibacterial characteristics of phenolic extracts obtained from SRs that have remained after EO distillation. SR extracts of Greek oregano, rosemary, spearmint, lemon balm, and Greek sage were assessed for their total phenolic content (TPC), antioxidant activity, and antimicrobial activity against Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, Staphylococcus aureus, Bacillus subtilis, Bacillus licheniformis, and Bacillus cereus in the concentration range of 500-3000 mg/L. The rosemary and Greek sage extracts exhibited the strongest antibacterial activities against all the Gram-positive species, while the spearmint and oregano extracts were less effective and only had an effect at the highest concentration used. The lemon balm extract did not show any inhibitory effect; however, it had the highest TPC, showing moderate antioxidant activity, along with spearmint. The oregano extract exhibited the strongest antioxidant activity, followed by Greek sage and rosemary. The experimental findings pointed to the potential use of extracts from post-distillation residues of MAPs as antimicrobials in the food industry, in addition to being rich sources of bioactive compounds.

Development of a functional Greek sheep yogurt incorporating a probiotic Lacticaseibacillus rhamnosus wild-type strain as adjunct starter culture

Greek yogurt is a fermented dairy product of high nutritional value that can be used as a matrix for the delivery of probiotics. The aim of this study was to develop a new probiotic Greek sheep yogurt with upgraded quality and functional characteristics. To do this, yogurt was manufactured by fermenting pasteurized milk with the commercial starter culture (Streptococcus thermophilus (ST), Lactobacillus bulgaricus (LB)) together with a probiotic Lacticaseibacillus rhamnosus (LR) wild-type strain (probiotic yogurt; PY). As a control, yogurt manufactured with only the starter culture (ST, LB) was used (conventional yogurt; CY) The survival of all three lactic acid bacteria (LAB) species (ST, LB, and LR) was monitored throughout the products’ shelf life (storage at 4 °C for 25 days), and also following exposure to a static in vitro digestion model (SIVDM). The population dynamics of total aerobic plate count (APC), Enterobacteriaceae, yeasts and molds grown in both yogurts were also determined. The total antioxidant activity (AA) of yogurts was comparatively determined using in parallel two different assays, whereas the Folin-Ciocalteu assay was used to determine their total phenolic content (TPC). At each sampling day, yogurts were also evaluated for their pH, titratable acidity (TA) and main sensory characteristics. The population of probiotic LR remained stable during the shelf life (and above 108 CFU/g). Yogurt starters (ST, LB) were not detected following SIVDM, whereas LR (in PY) presented a reduction of about only one log. The AA and TPC of PY were found significantly higher than that of CY (P < 0.05). At the end of storage (25th day), neither pH nor TA differed significantly between the two yogurt types, while no fungal growth was observed in the PY. Consumer sensory analysis did not reveal important differences between the two yogurt types during their shelf life. To sum up, the novel yogurt was able to deliver to consumers a high number of probiotic cells (>108 CFU/g), presented increased antioxidant power, had an expanded shelf life, and maintained its good sensory attributes.

In Vitro Antioxidant and Antibacterial Activities of Medicinal Flower Laligurans Rhododendron arboreum Collected from Kathmandu Valley, Nepal.

Rhododendron arboreum, known as Nepal's national flower and belonging to the Ericaceae family, thrives throughout the Himalayan region. This study investigates the antioxidant and antimicrobial potential of Rhododendron arboreum flowers. Three different extracts were prepared at concentrations ranging from 10 to 640 μg/mL and assessed for their total phenolic content (TPC), total flavonoid content (TFC), and DPPH radical scavenging activity. Results showed significant accumulation of antioxidant compounds (P < 0.05), with TPC levels of 37.78, 67.29, and 53.46 mg GAE/g and TFC values of 49.46, 67.46, and 65.71 mg QE/g for LGP, LGE, and LGA at 640 μg/mL, respectively. DPPH activity was highest in LGE (96.33%), followed by LGA (87.11%) and LGP (76.59%), compared to the standard (77.38%). The antibacterial properties were significant against Aeromonas hydrophila, Staphylococcus aureus, and Escherichia coli at 100% concentration, with inhibition rates of 15%, 16%, and 17% for LGP, LGE, and LGA, respectively. These findings indicate that Rhododendron arboreum petals, rich in bioactive compounds, possess strong antioxidant and antibacterial properties, making them potential candidates for developing cost-effective therapeutic formulations. Further research should focus on isolating specific bioactive compounds and understanding their molecular mechanisms to enhance therapeutic efficacy.

Cytotoxicity, Antioxidant Activities, GC-MS and HPLC Fingerprint Analyses of Different Extracts of Desmodium tortuosum (Sw.) DC

The family Fabaceae is the third-largest flowering plant family, and the genus Desmodium has exhibited a wide range of biological activities and a variety of chemical constituents. In the present study, different extracts of Desmodium tortuosum were evaluated for their cytotoxic and antioxidant activities, as well as their total phenolic content (TPC). The antioxidant activities were estimated using the 1,1'-diphenyl-2-picraylhydrazyl free radical (DPPH), while the cytotoxic activity was evaluated via the brine shrimp lethality test (BSLT). The antioxidant activity results revealed that the DPPH radical scavenging activity (SC50) ranged from 1.12 to 61.22 µg/ml with respect to ascorbic acid (SC50 = 7.45 µg/ml). Among all tested fractions, 90% methanol was the most active. On the other hand, the cytotoxic activities were arranged as follows: n-BuOH (LC50 = 310), EtOAc (LC50 = 350), and 70% methanol (LC50 = 380). High-Performance Liquid Chromatography-Fingerprint analyses were used to determine the chemical composition and relative proportions of phenolic compounds. GC-MS analysis indicated the presence of fatty acids and other compounds. The major identified compounds were Benzene (1-butyloctyl) (11.88%) and Himachalene &lt;α-&gt; (11.08%) for the ethyl acetate extract and 10-Undecenoic acid, methyl ester (25.50%) for unsaponifiable matter.

The antioxidant property of home-cooked orange-fleshed and purple-fleshed sweet potato

One property inherent to sweet potato because of the presence of phytochemicas is its antioxidant property. As proven by researches, antioxidant property is affected by cooking. This study determined the effect of four home cooking methods: steaming, boiling, baking, and frying on the antioxidant property of orange-fleshed and purple-fleshed sweet potatoes. The antioxidant property of raw and cooked we measured samples for their Total Phenolic Content (TPC) using Folin-Ciocalteu assay and their antioxidant activity based on the EC50 value of the DPPH assay. The TPC of orange-fleshed sweet potato was significantly increased by boiling and steaming. Baking and frying decreased the TPC of the orange-fleshed. The TPC of the purple-fleshed variety was not affected by the cooking methods but compared to the orange-fleshed, the TPC of the purple variety is significantly higher in both the raw and cooked forms. Based on the result of the DPPH assay, cooking significantly affected the antioxidant activity of both varieties (p&lt;0.05). Steaming gave the highest increase for both varieties. Boiling caused the lowest increase for the orange-fleshed but didn’t give a significant effect on the antioxidant activity of the purple-fleshed. Comparing the two varieties, the raw and cooked purple-fleshed sweet potato have better antioxidant activity based on DPPH assay except for the steamed samples wherein the antioxidant activity of steamed orange-fleshed sweet potato is significantly higher (p&lt;0.05) than that of the purple variety. It can be concluded that steaming is the best cooking method for the two sweet potato varieties. Keywords: Anti-oxidant, cooking, sweet potato, total phenolic content.

The Antioxidant Activity of Wild-Growing Plants Containing Phenolic Compounds in Latvia.

Ethnobotanical reports from Latvia show that Tanacetum vulgare, Calluna vulgaris, Quercus robur, Artemisa absinthium, and Artemisia vulgaris contain phenolic compounds that have antioxidant properties, which can be beneficial in the treatment and prophylaxis of many diseases. The aim of this study was to characterize the phenolic compounds and antioxidant properties of these plants. Plant extracts were prepared using ethanol or acetone and then freeze-dried. Their total phenolic content (TPC), total flavonoid content (TFC), and total tannin content (TTC) were determined and characterized by HPLC. Their antioxidant properties were determined using a DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay. C. vulgaris herb and T. vulgare leaf extracts contained the highest amounts of flavonoids, but the bark of Q. robur had mostly tannins and phenolic acids. A. absinthium and A. vulgaris had the lowest amounts of polyphenols. When compared using extraction solvents, all acetone extracts had more TPC, more TFC, and better antioxidant activity. All plants contained chlorogenic acid, which contributes to antioxidant properties. The analysed plant extracts could be used in future studies to develop medicinal products with antioxidant properties.

Total Antioxidant Potential, Total Phenolic Profile and Cytotoxic Activity Against Brain Cancer: Melocan and Galdirik§.

Brain cancer is known to be one of the most difficult types of cancer to cure. It has a serious impact on the lives of diagnosed people due to the insufficient treatment options and their side effects. The search for new alternative treatments is therefore ongoing. Melocan (Smilax excelsa L.) and galdirik (Trachystemon orientalis) are of great importance in both traditional culinary culture and traditional medicine around the Black Sea; however, the knowledge about their antioxidant and cytotoxic effects remains fairly limited. The aim of this study is to determine the antioxidant and cytotoxic activity of Smilax excelsa and Trachystemon orientalis on the C6 glioblastoma cell line. The plants of Smilax excelsa and Trachystemon orientalis were dried and extracted and then their total phenolic content (TPC) and phenolic profiles were studied. In addition, their total antioxidant status (TAS) and total oxidant status (TOS) were determined using an assay kit. We also analysed the total antioxidant activity (TAA) using the DPPH radical scavenging assay and the cytotoxic effect on the glioma cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay. According to the results, the water extracts of Smilax excelsa and Trachystemon orientalis had higher TPC (expressed in gallic acid equivalents on dry mass basis: 1158.17 and 262 mg/100 g, respectively) than the ethanol extracts. TAA expressed in Trolox equivalents on dry mass basis was 192.86 and 131.92 mg/100 g for Smilax excelsa and Trachystemon orientalis, respectively. The MTT assay showed that Trachystemon orientalis had a greater cytotoxic effect. In conclusion, the findings of the current study are promising for the development of new drugs. This is the first study that aims to evaluate the potential cytotoxic activity of two local Turkish plants, Smilax excelsa and Trachystemon orientalis, against C6 glioblastoma cells. The results confirm that both plants could be used as good therapeutic agents for the treatment of cancer in the future.

Chemical Profiling on Bioactive Stilbenoids in the Seeds of Paeonia Species Growing Wild in Greece

The seeds of Paeonia clusii Stern subsp. clusii and Paeonia mascula (L.) Mill. subsp. mascula growing wild in Greece, though not previously investigated, has been studied as a source of bioactive stilbenoids and other phenolics. Their methanol extracts were analyzed using ultra high-performance liquid chromatography—high-resolution mass spectrometry (UHPLC-HRMS), and among the identified metabolites (62), 19 paeoniflorin’s derivatives, 17 flavonoids and 12 stilbenes were detected. Moreover, through classic phytochemical separation procedures, twelve among them were isolated and fully spectrally determined as trans-resveratrol, trans-resveratrol-4′-O-β-D-glucopyranoside, cis-resveratrol-4′-O-β-D-glucopyranoside, trans-gnetin-H, trans-ε-viniferin, luteolin, luteolin-3′-O-β-D-glucopyranoside, luteolin-3′,4′-di-O-β-D-glucopyranoside, apigenin, hispidulin, paeoniflorin and benzoyl-paeoniflorin. All seed extracts were measured for their total phenolic content (TPC), appearing as a rich source (116.04 and 103.63 mg GAE/g extract, respectively), followed by free radical (DPPH) scavenging capacity (75.24% and 91.54% inhibition at the concentration of 200 μg/mL). The evaluation of tyrosinase inhibition for both extracts (61% and 70%, respectively) confirmed the potential for their future application in skin health care, comparable with other paeonies of Chinese origin, which are well-known as skin whitening and anti-aging promoters.

Effect of the Media in the Folin-Ciocalteu Assay for the Analysis of the Total Phenolic Content of Olive Products

The nutritional and economic value of oils is affected by its antioxidant properties linked to their total phenolic content (TPC). The analysis of antioxidants such as phenols may be affected by the lipophilic character of the media. Therefore, the accurate determination of TPC in oils deserves particular attention. This research has tested the effect of the alkaline medium in the quantification of TPC in extra virgin olive oil (EVOO) and olive pomace oil (OPO) using the Folin-Ciocalteu method. Seven different EVOO and OPO oils were used to gain representativity and study matrix effects in the analysis. Among the alkaline conditions assayed, the Folin-Ciocalteu method led to maximum TPC in EVOOs samples using 7.5% Na2CO3, whereas 35% Na2CO3 showed better characterization of TPC in OPOs than milder basic conditions. Therefore, when analyzing olive oil products, adjusting the alkaline media in the Folin Ciocalteu assay is important for optimal TPC determination. TPC analyses via Folin-Ciocalteu with different media was supported with antioxidant activities determined with reference assays: 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid cation radical and 2,2-diphenyl-1-picrylhydrazyl radical.

Changes in the chemical profile and bioactive potentialities of Kombucha fermented Salvia aegyptiaca tea

Kombucha is a traditionally non-alcoholic drink prepared by fermenting sweet-flavored black tea with tea fungus. In the present study, Salvia aegyptiaca tea was used as alternative substrate for kombucha fermentation due to its bioactivity which could improve the functional characteristics of kombucha. The prepared infusions (unfermented controls, without and with sugar) and fermented aqueous extracts were subjected to liquid-liquid extraction with ethyl acetate (EtOAc) and n-butanol (n-BuOH), sequentially, then compared in terms of their total phenolic content (TPC), antioxidant, anti-acetylcholinesterase (AChE), anti-inflammatory (anti-15-lipoxygenase), anti-xanthine oxidase (XOD) and cytotoxic activities. The kombucha beverage was obtained after longer period (11 days). Results indicated that fermentation reduced TPC in all extracts compared to unfermented samples (without and with sugar). The antioxidant capacity of S. aegyptiaca was enhanced by fermentation of n-BuOH (89%) and EtOAc (85%) extracts and inversely reduced in aqueous fraction. Nineteen phenolic compounds were identified and quantified using HPLC (high-performance liquid chromatography), whereas different aromatic compounds were detected using GC-MS (gas chromatography-mass spectrometry). The AChE, XOD and 15-lipoxygenase inhibitory effects as well as cytotoxic activity of all extracts were reduced by fermentation. The obtained results suggested that S. aegyptiaca tea is probably not suitable as substrate for kombucha production, as it can not be used as the only nitrogen source for tea fungus culture due to the low content of nitrogen in the leaves of the used plant.

ANTIOXIDANT AND Alfa-AMYLASE INHIBITION ACTIVITIES OF MEDICINAL PLANTS ARE TRADITIONALLY USED FOR THE TREATMENT OF DIGESTIVE DISORDERS IN THE NEAR EAST REGION

Medicinal plants have been used for longtime for treatment of many illnesses. Many plants were described in folk heritage to have anti-inflammatory activity to treat digestive diseases. In this study, thirteen plants commonly used by Jordanian folks to treat digestive disorders were investigated to find a connection between their contents and activities and their relationship with their assigned folk use. The ethanolic extracts of the plants were tested for their Total Phenolic Content (TPC), Total Tannin Content (TTC), Total Flavonoid Content (TFC) and their antioxidants activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). In addition to α-Amylase inhibitory activity of the plant extracts was determined. Correlations between TPC, TFC, TTC, protein content with the antioxidant activities (DPPH and ABTS), α-amylase inhibition were determined using Pearson correlation. The phenolic content and flavonoid content showed a high correlation with ABTS activity. The studied plants varied from activation to inhibition of α-Amylase, this may benefit people with hypoglycemia. This diversity of values directs people to which plant to use in case of multi-case disease.

Antioxidant and antithrombotic activities of the Distichochlamys citrea leaves extract

Distichochlamys citrea (DC) is an endemic ginger species used in treating associated-heart diseases in traditional medicine in Vietnam. However, scientific evidence to support the local use of this plant was limited. The present study aimed to investigate the antioxidant and antithrombotic activities of D. citrea extracts for the first time. The antioxidant activity of DC extracts was assessed by scavenging DPPH radical and measuring their total phenolic content (TPC). The antithrombotic activity was evaluated by inhibiting platelet aggregation and prolonging blood coagulation. Volatile components elucidated by GC-MS were docked with typical platelet receptors, including COX-1 and P2Y12. Results showed that the methanol extract of D. citrea exhibited a stronger DPPH scavenging ability (IC50 = 0.33 ± 0.00 mg/mL) and a higher TPC (8.09 ± 0.21%) than other extracts (p &lt; 0.05). On the other hand, the hexane extract of D. citrea (DC-HX) had a remarkable inhibiting impact on ADP-, collagen- and ristocetin–induced platelet aggregation in a dose-dependent manner (Pearson’s correlation, r &gt; 0.90, p &lt; 0.05). In contrast, this extract did not lengthen the clotting time through any factors, such as PT (prothrombin time), and TT (thrombin time), except for APTT (activated partial thromboplastin time) at 4 mg/mL of the extract. GC-MS revealed that oxygenated hydrocarbons (54.45%) dominated the volatile profile of DC-HX, followed by sesquiterpens (37.18%) and diterpenes (6.66%). In the platelet aggregation process, several compounds in DC-HX were firmly bound to COX-1 and P2Y12, which might partly explain the significant antiaggregatory activity of this fraction. In conclusion, Distichochlamys citrea may be a potential source of active phytoconstituents for treating radicals- and cardiovascular-associated diseases.