FRAP Methods Research Articles

Preliminary Study on the Chemical and Biological Properties of Propolis Extract from Stingless Bees from the Northern Region of Brazil

Natural products are historically regarded as the main sources of bioactive compounds to fight the most diverse diseases; among them, propolis deserves to be highlighted due to several biological activities, such as antioxidant, anti-inflammatory, healing, antibacterial and antileishmanial activity. In this study, the antioxidant and antipromastigote activities and the cytotoxicity of propolis of the Scaptotrigona aff. postica stingless bee were evaluated. Propolis extract was analyzed by infrared spectroscopy, thermogravimetry and spectrophotometry for total polyphenols and flavonoid contents. Antioxidant activity was assessed spectrophotometrically by the DPPH, ABTS and FRAP methods, while antipromastigote activity and cytotoxicity were assessed by the MTT assay. The infrared spectra showed the characteristic bands of both phenols and alcohols. The thermogravimetry study revealed two events and thermal stability around 370 °C, while differential scanning calorimetry showed two endothermic events and an exothermic event. Total polyphenol and flavonoid contents were 21.29 ± 0.003 mg/g and 8.17 ± 0.00 mg/g, respectively, and the antioxidant activities identified by the DPPH, ABTS and FRAP methods were 910.09 ± 0.0264 µM Trolox (IC50 18.9 ± 0.01 µg/mL), 859.97 ± 0.0854 µM Trolox (IC50 692 ± 0.01 µg/mL) and 1613.67 ± 0.2610 µM Trolox (IC50 80 ± 0.1 µg/mL), respectively. The satisfactory antioxidant activity of propolis can be related to the high content of phenolic compounds, which adds value to this product and can contribute to the development of meliponiculture in the Brazilian state of Pará. The propolis extract caused a toxic effect on promastigote forms of Leishmania amazonensis at all concentrations tested, with an IC50 value of 1.50 µg/mL and a statistically significant difference compared to the negative control (p < 0.001). These results show that the propolis extract from S. postica bees may be a promising alternative for treatment against promastigote forms of L. amazonensis.

Phenolic Content, Antioxidant Potential, and Antimicrobial Activity of Uvaria chamae (Annonaceae), a Food Plant from Burkina Faso.

The study aimed to evaluate phenolic content and antioxidant and antibacterial potentials of the fractions of the hydroethanolic extract of Uvaria chamae leaves, a food plant from Burkina Faso. Thus, the hexane, dichloromethane, ethyl acetate, and butanol fractions of the hydroalcoholic extract after drying were used to determine phenolic compound content, antioxidant activity, and antimicrobial potential on strains of pathogenic bacteria responsible for food contamination. Phytochemical analyses were performed according to standardized methods, while antioxidant activity was evaluated by DPPH and FRAP methods. The antibacterial activity of the fractions was determined by diffusion and microdilution methods on the agar medium with gentamicin as a reference antibiotic. All the six strains, namely, Salmonella typhi ATCC 19430, Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 9027, Bacillus cereus ATCC 13061, and Listeria monocytogenes ATCC 7644, were sensitive to the fractions tested. Minimum inhibitory concentrations ranged from 37 µg·mL-1 to 1.67 mg·mL-1, respectively, gentamicin and butanolic fractions, while minimum bactericidal concentrations of the fractions ranged from 0.037 to 2.500 mg·mL-1 depending on the bacterial strain. Antioxidant activity varied significantly between fractions. For DPPH free radical scavenging activity, the butanol fraction was the most active, with an IC50 of 280 μg/mL, while the lowest activity (705 μg/mL) was recorded by the hexane fraction. Those of trolox and ascorbic acid used as standards were 80 and 100 μg/mL, respectively. Ferric reducing power (FRAP) ranged from 0.34 to 0.40 mmol EAA/g extract for the hexanic and ethyl acetate fractions, respectively. Phenolic compound contents also varied significantly between fractions. Butanoic and ethyl acetate presented the best contents of total phenolics and flavonoids, respectively. Significant and positive correlations were also recorded between phenolics and antioxidant activities. The antibacterial and antioxidant activities of the active fractions would be related to their richness in bioactive compounds, including phenolic, which are powerful natural antioxidants. U. chamae leaf extracts could therefore be used as dietary supplements to boost the immune system and prevent bacterial infections.

Evaluation of heat-induced changes and 5-hydroxymethylfurfural formation in mare milk - a comparative study to cow milk

Mare milk is known for therapeutic properties due to the presence of bioactive components that are sensitive to thermal treatments and tend to lose their activity. Accordingly, mare milk is consumed raw or frozen, but for food safety reasons recent studies suggest mandatory pasteurization of mare milk before consumption. The aim of this study was to examine the effects of different heat treatments on mare milk quality and compare those to heat induced changes in cow milk. In all milk samples, the total dissolved solids (TDS), electrical conductivity (EC), antioxidant capacity (AC) by the DPPH and FRAP methods, changes in colour (ΔE*), concentration of 5-hydroxymethylfurfural (HMF) and the total phenols (TPC) were determined. Heat induced protein denaturation was monitored by SDS-PAGE, while NIR was applied for qualitative analysis of structural changes. In-bottle sterilization at 116 °C/16ʹ and 120 °C/5ʹ showed to be inappropriate for mare milk processing, since they resulted in the most intense colour changes (ΔE*>5), the highest free and total HMF concentrations (40.70 μmol/L free, 70.26 μmol/L total HMF at 116 °C/16ʹ; 35.49 μmol/L free, 58.12 μmol/L total HMF at 120 °C/5ʹ) and the most intense protein denaturation. On contrary, the applied HTST regimes (72 °C/20”, 85 °C/30”, 90 °C/5ʹ) and thermisation at 63 °C/15” were appropriate for mare milk processing considering the studied qualitative changes. Thereby, the HMF concentration, FRAP, TPC and ΔE* value, combined with NIR analysis showed a good potential to be used as rapid and useful tools for monitoring the intensity of heat induced changes in mare milk.

Variation in Nutritional Components and Antioxidant Capacity of Different Cultivars and Organs of Basella alba

Basella alba is a frequently consumed leafy vegetable. However, research on its nutritional components is limited. This study aimed to explore the variation in the nutritional components and antioxidant capacity of different cultivars and organs of Basella alba. Here, we primarily chose classical spectrophotometry and high-performance liquid chromatography (HPLC) to characterize the variation in nutritional components and antioxidant capacity among different organs (inflorescences, green fruits, black fruits, leaves, and stems) of eight typical cultivars of Basella alba. The determination indices (and methods) included the total soluble sugar (anthrone colorimetry), total soluble protein (the Bradford method), total chlorophyll (the ethanol-extracting method), total carotenoids (the ethanol-extracting method), total ascorbic acid (the HPLC method), total proanthocyanidins (the p-dimethylaminocinnamaldehyde method), total flavonoids (AlCl3 colorimetry), total phenolics (the Folin method), and antioxidant capacity (the FRAP and ABTS methods). The results indicated that M5 and M6 exhibited advantages in their nutrient contents and antioxidant capacities. Additionally, the inflorescences demonstrated the highest total ascorbic acid and total phenolic contents, while the green and black fruits exhibited relatively high levels of total proanthocyanidins and antioxidant capacity. In a comparison between the green and black fruits, the green fruits showed higher levels of total chlorophyll (0.77–1.85 mg g−1 DW), total proanthocyanidins (0.62–2.34 mg g−1 DW), total phenolics (15.28–27.35 mg g−1 DW), and ABTS (43.39–59.16%), while the black fruits exhibited higher levels of total soluble protein (65.45–89.48 mg g−1 DW) and total soluble sugar (56.40–207.62 mg g−1 DW) in most cultivars. Chlorophyll, carotenoids, and flavonoids were predominantly found in the leaves of most cultivars, whereas the total soluble sugar contents were highest in the stems of most cultivars. Overall, our findings underscore the significant influence of the cultivars on the nutritional composition of Basella alba. Moreover, we observed notable variations in the nutrient contents among the different organs of the eight cultivars, and proanthocyanidins may contribute significantly to the antioxidant activity of the fruits. On the whole, this study provides a theoretical basis for the genetic breeding of Basella alba and dietary nutrition and serves as a reference for the comprehensive utilization of this vegetable.

Total phenolic content and antioxidant activity of extracts obtained from tobacco waste seeds, grown under organic production

This study aimed to determine the total phenolic content of Oriental tobacco waste seeds, grown under organic production, and to evaluate their antioxidant activity by extraction with different solvents under different conditions. The extraction was performed with H2O, 99.9% CH3OH, 60% CH3OH, and 96% C2H5OH under maceration and ultrasonic extraction at 20°C and 40°C. All solvents were used in a volume of 4 mL, 5 mL, and 6 mL. The total phenolic content varied between 0.89 mg/g GAE (maceration; sample/solvent ratio 0.1g/5mL, C2H5OH) and 5.85 mg/g GAE (maceration; sample/solvent ratio 0.1g/6mL, C2H5OH). Ethanolic and 60% methanolic extracts had the highest antioxidant activity as determined by the DPPH method; 60% methanolic and water extracts had the highest antioxidant activity as determined by the ABTS method; while methanolic and 60% methanolic extracts had the highest antioxidant activity as determined by the FRAP method. In addition, the content of nicotine in tobacco seed extract was not detected.

Design, synthesis of new 2,4-thiazolidinediones: In-silico, in-vivo anti-diabetic and anti-inflammatory evaluation

In this study, a series of nine novel heterocyclic compounds were synthesized through a concise three-step reaction process. The synthesis involved Knoevenagel condensation at the 5th position of the 2,4-thiazolidinedione or rhodanine ring-system. Comprehensive physicochemical and spectral analyses, including FTIR, Mass, 1H NMR and 13C NMR, were performed to characterize the synthesized compounds. The synthesized derivatives were subjected to evaluation for their potential in various therapeutic domains. In-vivo anti-diabetic activity was assessed diabetes induced wistar rats, anti-inflammatory effects were gauged using the carrageenan and formalin induced rat paw edema model. Additionally, the in-vitro PPAR-γ modulatory activity, glucose uptake by using Saccharomyces cerevisiae and rat hemidiaphragm and cyclooxygenase inhibitory activity along with scavenge free radicals was tested by FRAP and DPPH method. According to the potential binding patterns of the most potent anti-diabetic compounds, namely 7a and 13a with the active sites of target PPAR-γ (PDB ID: 5U5L), was obtained through molecular docking using Schrodinger’s Glide model. Among the tested compounds, the compound 13a demonstrated significant antidiabetic activity with reduction in blood glucose levels (108.5 ± 2.171 mg/dL), comparable to the effect of pioglitazone (101.66 ± 0.95 mg/dL), similarly anti-inflammatory activity at fourth hour paw volume 93.6% and thickness at 3.99 ± 0.076 mm, respectively closer to that of standard drug diclofenac sodium (91.2% and 4.7 ± 0.057 mm) in carrageenan-induced paw edema in rat. The compound 13a displayed promising COX-2 inhibitory activity (IC50 = 7.82 μM) and DPPH antioxidant activity showcasing its multifaceted therapeutic potential. This study not only presents multi-targeting approach and highlights the significant potential compounds as a lead molecule for further therapeutic development.

Phenolic Compounds in Berries of Winter-Resistant Actinidia arguta Miq. and Actinidia kolomikta Maxim.: Evidence of Antioxidative Activity.

Variations between fruit cultivars can significantly impact their biochemical composition. The present research examined the variability in the qualitative and quantitative content of phenolic compounds in berry extracts of Actinidia kolomikta and Actinidia arguta cultivars. Additionally, antioxidant activities of berry extracts were evaluated. The total phenolic, flavonoid, proanthocyanidin contents and hydroxycinnamic acid derivatives were determined using the appropriate methodologies. The average amount of phenolic compounds in A. kolomikta berries (177.80 mg/g) was three times higher than that of A. arguta (54.45 mg/g). Our findings revealed that berries of A. kolomikta and A. arguta accumulated, on average, 1.58 RE/g DW (rutin equivalent/g dry weight) and 0.615 mg RE/g DW of total flavonoids, 1439.31 mg EE/g DW (epicatechin equivalent/g dry weight) and 439.97 mg EE/g DW of proanthocyanidins, and 23.51 mg CAE/g DW (chlorogenic acid equivalent/g dry weight) and 5.65 mg CAE/g DW of hydroxycinnamic acid derivatives, respectively. The cultivars of both species were characterized by higher antioxidant activity of total phenolic compounds determined using CUPRAC and FRAP methods compared to the ABTS•+ method. The variability in phenolic compounds' qualitative and quantitative content in tested berry extracts was evaluated by applying ultra-high performance liquid chromatography (UHPLC) coupled to mass spectrometry in tandem with electrospray ionization. Significant intraspecific differences in the amounts of total phenolic compounds, total flavonoid compounds, proanthocyanidins, and hydroxycinnamic acid derivatives were determined among cultivars. Four phenolic acids, eight flavonols, two flavones, and five flavon-3-ols were identified in the berry extracts.

Impact of Polyvinylpyrrolidone-Vinyl Acetate Copolymer and Sodium Starch Glycolate Excipients on Phenolic Extraction from Red Clover: Enhancing Biological Activity and Antioxidant Potential.

Adding certain excipients during the extraction process can enhance the concentration of target compounds, leading to potentially increased biological properties of the plant extract. This study explores the impact of PVP/VAC and SSG excipients on red clover bud extracts, aiming to enhance their concentration of target compounds and, consequently, their biological properties. The antioxidative potential was evaluated using DPPH, ABTS, and FRAP methods, and the chemical profile was determined using mass spectrometry. Antibacterial activity against various strains was determined through the minimal inhibitory concentration (MIC) method. The results revealed that the excipient-enriched samples exhibited significantly elevated antioxidant activities as well as phenolic and flavonoid contents compared to control samples. Notably, sample V1E3 demonstrated the highest antioxidant potential, with 52.48 ± 0.24 mg GAE/g dw (phenolic content), 463 ± 6.46 μg TE/g dw (ABTS), 12.81 ± 0.05 μg TE/g dw (DPPH), and 29.04 ± 1.16 mg TE/g dw (post-column ABTS). The highest flavonoid content was found in the S1E3 sample-24.25 ± 0.17 mg RU/g dw. Despite the increased antioxidant potential, no significant variance in antimicrobial activity was noted between the test samples and controls. This implies that excipients may hold the potential to enhance the biological properties of red clover extracts for pharmaceutical applications. These findings contribute valuable insights into optimizing extraction processes for improved functionality and application of plant-derived compounds in therapeutic formulations.

Antioxidant Activity of Ethanol Extract on Qust Al Hindi (Saussurea lappa) Roots Using the FRAP Method

Qust al hindi (Saussurea lappa) is a plant that has antioxidant activity, especially in the roots. Qust al hindi contains several chemical compounds including flavonoids, steroids, terpenes, alkaloids, sesquiterpenes, costunolide, dehydrococtus lactones, cynaropicrin, and chlorogenic acid. This study aims to determine the antioxidant activity of the ethanol extract of qust al hindi root using the FRAP method. Samples that had become powder were extracted using the soxhletation method with 96% ethanol and obtained a % rendition of 5.302%. The extract obtained was measured using a UV-Vis spectrophotometer at a maximum wavelength of 718 nm after being mixed with several FRAP reagents, using a quercetin standard. The results of the antioxidant analysis showed that the average antioxidant activity of the ethanol extract of the qust al hindi root (Saussurea lappa) using the Frap method was 10.3671 mgQE/g extract. Which means that the antioxidant activity of each g of extract is equivalent to the antioxidant activity of 10.3671 mg of quercetin.

THE DEVELOPMENT AND VALIDATION OF ANALYTICAL METHOD FOR EVALUATING GALLIC ACID IN ETHYL ACETATE FRACTION (EAF) OF SNEDDS FORMULATION: QUANTITATIVE ANALYSIS WITH IN VITRO ASSAY

Objective: This study aimed to develop a simple, accurate, precise, sensitive, robust, and stable analytical method for the evaluation of gallic acid in Self-Nanoemulsifying Drug Delivery System (SNEDDS) incorporating ethyl acetate fraction (EAF) of Melastoma malabathricum leaves in combination with Gentamicin. Methods: Validation process followed ICH guidelines and applied a reverse phase HPLC method with a mobile phase of acetonitrile-phosphoric buffer at pH 3.03 (20:80 v/v). The stationary phase consisted of a VP-ODS shim-pack C-18 column (250x4.6 mm) with a flow rate of 0.2 ml/min and detection at 263 nm using an Ultraviolet detector. Additionally, antioxidant activity was assessed through the DPPH and FRAP methods, and SPF value was determined with a UV/Vis spectrophotometer in the 290-390 nm wavelength range. Results: The results showed that the retention time of quercetin was 16.648 min with a tailing factor of 1.623. The regression equation (y=224689x-989000) had a concentration range of 10-55 µg/ml and a correlation value of 0.9920. Limit of Detection (LOD) and Limit of Quantification (LOQ) were found to be 2.394±0.086 and 7.254±0.260 µg/ml, respectively. Method accuracy, determined by recovery values at concentrations of 50%, 100%, and 150%, ranged from 91.18% to 109.49%. Repeatability inter-day variations were expressed as %RSD values of 1.027-1.963% for AUC and 0.150-0.145 for RT. Moreover, the applied method showed stability within a temperature range of 14 °C–35 °C. Analysis showed gallic acid content of 1.773±0.049 mg/g in SNEDDS EAF formulation. Antioxidant activity measured through the DPPH and FRAP methods yielded IC50 values of 4.167±0.552 µg/ml and 20.253±0.619 µg/ml, respectively, while SPF value at SNEDDS concentration of 150 µg/ml was 36.993±0.183. Conclusion: This study successfully developed a precise, accurate, specific, and stable method for quantifying gallic acid levels in SNEDDS EAF of Melastoma malabathricum leaves in combination with Gentamicin. Therefore, SNEDDS EAF formulation exhibited an effective wound-healing potential, supported by a robust quality control process.

SELECTION OF THE OPTIMAL EXTRACTION MODULE IN THE DEVELOPMENT OF THE TECHNOLOGY OF PRODUCTION OF BLACK AND GREEN TEA EXTRACTS (Camellia sinensis) WITH HIGH INDICATORS OF ANTIOXIDANT ACTIVITY

It is known that various factors of extraction, such as the type of solvent, temperature, time, solvent system, degree of grinding of raw materials, extraction modulus significantly affect the level of antioxidant properties of plant products. The aim of our study was to select the optimal extraction module for two types of tea (Camellia sinensis), to obtain extracts with high values of total soluble solids, phenols, flavonoids, tannins, antiradical activity according to the DPPH method, restoring strength according to the FRAP method. The objects of the study were extracts of two types of tea obtained using water, with a grinding degree of 0.5 mm, an extraction temperature of 40–50 °C, an extraction time of 24 h, and various versions of extraction modules 1 : 10, 1 : 15, 1 : 20. The indicator of the content of dry soluble substances in black and green tea reaches high values when using the extraction module 1 : 10 (9% and 9.6%, respectively), the maximum amount of phenolic substances (3139 mg (HA) / 100 g and 2045 mg (HA) / 100 g), flavonoids (1644 mg (K) / 100 g and 718 mg (K) / 100 g), tannins (123 mg catechin / 100 g and 56 mg catechin / 100 g) were extracted from black and green tea extracts at extraction module 1 : 10. The highest index of restorative power was observed in black and green tea extracts with an extraction modulus of 1 : 10 (8.73 mmol Fe2+ / kg and 15.84 mmol Fe2+ / kg). At an extraction modulus of 1 : 10, black and green tea extracts exhibited the least antiradical activity (Ec50 = 0.39 mg / cm3 and Ec50 = 0.69 mg / cm3). Thus, we can recommend the value of the module 1 : 10 as the most acceptable for obtaining extracts from black and green tea with a high level of the studied parameters.

Biogenic Ag2O nanoparticles with "Hoja Santa" (Piper auritum) extract: characterization and biological capabilities.

The 'sacred leaf' or "Hoja Santa" (Piper auritum Kunth) has a great value for Mexican culture and has gained popularity worldwide for its excellent properties from culinary to remedies. To contribute to its heritage, in this project we proposed the green synthesis of silver oxide nanoparticles (Ag2O NPs) using an extract of "Hoja Santa" (Piper auritum) as a reducing and stabilizing agent. The synthesized Ag2O NPs were characterized by UV-Visible spectroscopy (plasmon located at 405nm), X-ray diffraction (XRD) (particle size diameter of 10nm), scanning electron microscopy (SEM) (particle size diameter of 13.62 ± 4.61nm), and Fourier-transform infrared spectroscopy (FTIR) (functional groups from "Hoja Santa" attached to nanoparticles). Antioxidant capacity was evaluated using DPPH, ABTS and FRAP methods. Furthermore, the antimicrobial activity of NPs against a panel of clinically relevant bacterial strains, including both Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Salmonella Enteritidis and Escherichia coli O157:H7), was over 90% at concentrations of 200µg/mL. Additionally, we assessed the antibiofilm activity of the NPs against Pseudomonas aeruginosa (reaching 98% of biofilm destruction at 800µg/mL), as biofilm formation plays a crucial role in bacterial resistance and chronic infections. Moreover, we investigated the impact of Ag2O NPs on immune cell viability, respiratory burst, and phagocytic activity to understand their effects on the immune system.

Kombucha as a Potential Active Ingredient in Cosmetics-An Ex Vivo Skin Permeation Study.

Kombucha is a non-alcoholic beverage, that is increasingly used in the cosmetic industry. The available literature reports the positive effects of kombucha on the skin, in particular its antioxidant action. However, there is a lack of information on skin permeation and the accumulation of active ingredients showing such effects. Skin aging is largely dependent on oxidative stress, therefore in our study we assessed the ex vivo permeation of two types of kombucha (green and black tea) through porcine skin. The antioxidant activity (DPPH, ABTS, FRAP methods) and total polyphenol content of these extracts were determined before and after permeation testing. Moreover, the content of selected phenolic acids as well as caffeine was assessed. Skin permeation was determined using a Franz diffusion cell. The antioxidant activity of both Kombuchas was found to be high. In addition, gallic acid, chlorogenic acid, protocatechuic acid, coumaric acid, m-hydroxybenzoic acid, and caffeine were identified. A 24-h ex vivo study showed the permeation of some phenolic acids and caffeine and their accumulation in the skin. Our results confirm the importance of studying the skin permeation of what are still little known ingredients in cosmetic preparations. Evaluation of the accumulation of these ingredients can guarantee the efficacy of such preparations.

Effects of Particle Size on Physicochemical and Nutritional Properties and Antioxidant Activity of Apple and Carrot Pomaces.

The food processing industry is growing rapidly and producing large amounts of by-products, such as pomaces, which are considered as no-value waste and cause significant environmental pollution. The main by-products of fruit juice processing companies are apple and carrot pomaces, which can be used to create new functional food products. In the present study, the effects of particle size (PS) on the proximate composition, nutritional properties, and antioxidant activity of apple pomace flour (APF) and carrot pomace flour (CPF) were determined. Four different PS fractions, PS > 1 mm, 1 > PS > 0.71 mm, 0.71 > PS > 0.18 mm, and 0.18 > PS > 0.075 mm were used for the present study. Their vitamin, carotenoid, organic acid, and reducing sugar contents were determined using HPLC. The proximate compositions of each PS fraction of the AP and CP flours were determined using recommended international standard methods. DPPH, FRAP, and Folin-Ciocalteu methods were used to measure their antioxidant activity and total phenolic compounds, respectively. The moisture content (around 12.1 mg/100 g) was similar in all PS fractions and in both flours. The APF had lower protein (4.3-4.6 g/100 g dw) and ash (1.7-2.0 g/100 g dw) contents compared to the CPF, with protein contents ranging from 6.4-6.8 g/100 g dw and ash contents ranging from 5.8-6.1 g/100 g dw. Smaller particles, regardless of flour type, exhibited higher sugar and phenolic contents and antioxidant activity, while vitamins were more abundant in particles larger than 1 mm. In the APF, larger particles had a higher fiber content than smaller particles, while their fat content was the lowest. PS also had an impact on the results of the carotenoid contents. This study underscores the direct impact of PS on the distribution of sugars, crude fiber, fat, carotenoids, vitamins, total phenolic compounds, and antioxidant activity in pomaces.

Bioactive components, antioxidant capacity, and antimicrobial activity of Berberis crataegina fruit

Research highlighting the benefits of plants provides possibilities for their application as food preservatives and in complementary medicine. The fruits of the wild shrub species Berberis crataegina, which humans eat, were examined in this study. The objective has been to ascertain the fruit's bioactive constituents, including minerals, phenolic compounds, fatty acids, and volatile components, in addition to its antioxidant and antibacterial properties. The antioxidant capacity of B. crataegina fruit was investigated in vitro by DPPH, DMPD, ABTS, FRAP, CUPRAC, and Total antioxidant methods. Additionally, the disk diffusion technique was used to assess its antibacterial impact on fungus and bacteria. It was determined that the fruit of B. crataegina is rich in Ca (27399 ppm), K (9634 ppm) Mg (5052 ppm), and Fe (470 ppm), contains essential oils such as alpha-linolenic acid (37%), and oleic acid (14%). Strong antioxidant qualities were demonstrated by B. crataegina, particularly in the ABTS and CUPRAC assays. In addition to 47 volatile compounds consisting mostly of aldehydes, fatty acids, and terpenes, 52 phenolic compounds were detected, including chlorogenic acid, rutin hydrate, and procyanidin B2. It also showed antimicrobial properties on S. aureus, P. aeruginosa, and K. pneumoniae.

Phytochemical Profile, Acute Toxicity, Antioxidant and Anti-inflammatory Activity of Hydroethanolic Extracts from Odontonema strictum (Nees) Kuntze (Acanthaceae) Root and Stem

Background: The leaves of Odontonema strictum (Nees) Kuntze (Acanthaceae), a decorative plant native to Latin America, are used to treat hypertension in alternative medicine. However, the other parts of the plant have not yet been investigated for their antihypertensive properties. Aims: Our study aimed to investigate phytochemical groups with antihypertensive potential, antioxidant and anti-inflammatory properties, and the safety of using stems and roots hydroethanolic extracts.
 Methodology: Phytochemical screening by HPTLC and determining flavonoids and total polyphenols were carried out. The antioxidant activity was evaluated using ABTS, FRAP, DPPH, and LPO methods. The inhibitory activity of Phospholipase A2 and 15-lipoxygenase was determined. Finally, acute oral toxicity was carried out on female mice NMRI.
 Results: The hydroethanolic extracts of Odontonema strictum root (HE_ROS) and stem (HE_SOS) contain tannins, sterols, triterpenes, flavonoids, and saponosides. HE_SOS gave the highest levels of flavonoids (23.69±1.10 mg QE/g) and total phenolics (64.15±4.02 mg TAE/g. The two hydroethanolic extracts had antioxidant activity, with HE_ROS being the best. However, these activities were lower than Trolox (p<0.05). The extracts have a moderate inhibitory effect on 15-lipoxygenase and Phospholipase A2. Finally, HE_ROS and HE_SOS are practically non-toxic when administered once orally.
 Conclusion: This study provided scientific data and could justify the use of Odontonema strictum in the treatment of hypertension.

Optimization of extraction and lyophilization conditions of Feretia apodanthera (Rubiaceae) leaf powders for galenic formulation

Feretia apodanthera (Rubiaceae) is used in traditional medicine for the treatment of various pathologies. Its leaves are chewed and swallowed to treat stomach aches, sleep disorders, etc. With the aim of improving the extraction method in order to obtain high contents of phytochemical compounds and good antioxidant activity, this study aimed to highlight the extraction and lyophilization conditions of two extracts (aqueous and hydro-ethanolic) leaves of Feretia apodanthera.
 An aqueous and hydro-ethanolic extraction was carried out from the leaf powder of Feretia apodanthera, after a maceration plan (mass/volume ratio and extraction time). The extracts obtained were freeze-dried (flask size, filling volume and freeze-drying time) in order to determine the optimal extraction conditions. A phytochemical screening of the extracts with extreme yields of different solvents was carried out by TLC, which led to the determination of certains compounds of interest and the evaluation of the antioxidant activity by the DPPH and FRAP method.
 The optimal maceration conditions were 02 hours and m/V ratio of 1/20 for the aqueous extract and those of the ethanolic extract were 30 min and m/V ratio of 1/20. The optimal freeze-drying conditions were 60h and a 500ml flask 1/3 filled. The presence of flavonoids, tannins, saponosides, coumarins, triterpenes and sterols has been highlighted. The phenolics compounds contents of hydro-ethanolic lyophilisates were higher than those of aqueous lyophilisates. There was no statistical difference between the antioxidant activity of the different extracts.
 The optimal conditions will serve as a standard for the production of the extract necessary for the formulation.
 Keywords : Feretia apodanthera, extraction, freeze-drying, phenolics compounds, antioxidant.

Extraction of Phycocyanin and Chlorophyll from Spirulina by “Green Methods”

Phycocyanin is a pigment–protein complex from the group of phycobiliproteins obtained from Spirulina (Arthrospira platensis), with possibilities for various applications in food and pharmaceutical technologies. It is a natural colorant for food and cosmetic products. This study aimed to investigate the effect of ultrasonic and microwave extraction conditions on antioxidant activity (AOA), chlorophyll content, and the content and purity index of phycocyanin in aqueous and alcoholic extracts of Spirulina (Arthrospira platensis). For this purpose, ultrasonic extraction with water or ethanol was performed at 20 °C, 30 °C, and 40 °C for 1, 2, and 3 h at an ultrasonic frequency of 36 kHz, 40 kHz, and 45 kHz. Microwave water extraction was performed for 60 s, 120 s, and 180 s. For each of the obtained samples, three parallel measurements of antioxidant activity were made by DPPH and FRAP methods, and chlorophyll content and phycocyanin yield and purity index were determined spectrophotometrically. Ultrasonic extraction resulted in a higher yield and purity index of phycocyanin compared to microwave extraction. The highest yield of 14.88 mg g−1 with a purity index of 1.60 was achieved at a temperature of 40 °C for one hour and an ultrasonic wave frequency of 40 kHz. A relatively low yield of 4.21 mg g−1, but with a purity index of 2.67, was obtained at a temperature of 30 °C, a time of two hours, and an ultrasonic frequency of 40 kHz. Chlorophyll b content at 20 °C, for two hours and ultrasonic frequency 40 kHz was 1.400 mg g−1. The study proposes ultrasonic extraction as a green method to obtain phycocyanin of varying purity index that may be used for food, cosmetic, or biomedical purposes.

Ability of Selected Monoterpenes to Reduce Fe(III) Ions Being Pro-Neurodegenerative Factors: Tests Based on a FRAP Reaction Extended to 48 Hours.

Monoterpenes are secondary plant metabolites, and such volatile compounds have antioxidant, antibacterial, antiviral, and enzyme inhibitory properties. These compounds are also able to reduce the potentially pro-neurodegenerative trace metal ions that can be sources of free radicals. One basic method used to evaluate the ability of chemical compounds to reduce Fe(III) is FRAP. To date, most studies based on a FRAP assay were performed within several dozen minutes. However, taking into account the diversity of compounds, it is justified to observe their activity over a much longer period of time. The present study aimed to observe the activity of isopulegol, γ-terpinene, α-terpinene, linalool, carvone, citral, and α-phellandrene over a 48 h period. Our study indicates that the lengthened reaction period enhanced activity from several dozen to several hundred percent. The obtained results also revealed an explicit high correlation of the increase in the activity of compounds with the increase in monoterpene concentration. Due to the hydrophobic character of monoterpenes, the FRAP method was modified by the addition of Tween 20. The highest activity was obtained for α-terpinene and γ-terpinene.

Phytochemical, Antioxidant Activity, and Toxicity of Wild Medicinal Plant of Melitotus albus Extracts, In Vitro and In Silico Approaches.

Morocco is known for its high plant biodiversity, but many plants are poorly valorized. For this reason, this study aims to valorize the methanolic and aqueous extracts of Melitotus albus leaves by studying their antioxidant activity and toxicity. The extracts' antioxidant activity is assessed using the FRAP, DPPH, CAT, and ABTS methods. The chemical composition was determined using LC-MS analysis and evaluated using in silico studies. The results revealed that the total polyphenol content of the aqueous extract, 259.26 ± 7.79 (mg GAE/g), is higher than that of the methanolic extract, 131.41 ± 12.64 (mg GAE/g). The antioxidant activity by the methods of DPPH, ABTS, and phosphor molybdenum of aqueous extracts (0.087 ± 0.015, 0.014 ± 0.001 and 6.157 ± 1.050 mg eq vit C/g, respectively) is greater than that of methanolic extracts (0.107 ± 0.02, 0.167 ± 0.03, and 0.453 ± 0.014 mg eq vit C/g, respectively). The reducing power of iron (FRAP) shows that the methanolic extract has a greater reducing power than that of the aqueous extract with a low IC50 (0.011 ± 0.003 and 0.199 ± 0.016 mg/mL, respectively). The study of acute and subacute toxicity shows that the administration of the aqueous extract of M. albus at different doses increases the body weight of rats without modifying their general behavior. The M. albus extract had a 99.99% total phenolic content, as determined by LC-MS, consisting of 12 different components. The primary constituents of the extract are chlorogenic acid (43.68%), catechin/epicatechin (24.82%), quercetin-3-O-glucuronic acid (9.91%), naringin (7.64%), and p-hydroxybenzoic/salicylic acid (2.95%). The in-silico study showed that these compounds can passively permeate through the blood and have a beneficial effect on various organs of the body. Based on these results, M. albus can be used as a medicinal plant in phytotherapy, cosmetics, or as a dietary supplement. The bioactive compounds of these plants will require a lot of further effort in terms of isolation and characterization.