Source Of Natural Antioxidants Research Articles

Quantitative and Qualitative Determination of Polyphenolic Compounds in Castanea sativa Leaves and Evaluation of Their Biological Activities

The aim of the study was to evaluate the polyphenol profile of Castanea sativa leaf methanolic extract and further evaluate its biological activities in vitro. After purification with an RP-18 resin, the extract was assessed for its polyphenol profile by UPLC-PDA-MS/MS, as well as for the antioxidant potential (ABTS, CUPRAC, ChA, ROS scavenging methods), anticancer, antiobesity, antidiabetic and antimicrobial potential. Eighteen polyphenols were identified and the dominant compounds were chestatin followed by quercetin 3-O-glucoside. The total phenolic content of the extract showed a value of 1426.55 mg/100 g d.w. The obtained preparation showed the ability to scavenge O2•− (0.067 mg/mL) and OH• (0.207 mg/mL) radicals and had a stronger anti-obesity than anti-diabetic effect. Additionally, this extract exhibited a strong anticancer activity against the Caco-2 line (153.54 µg/mL), with anti-migratory and anti-proliferative activity. In turn, among the tested strains, the highest activity was demonstrated against Staphylococcus aureus. Moreover, the effects demonstrated were strongly dependent on the content of polyphenols. In conclusion, C. sativa is a promising source of natural antioxidant, antibacterial, antiobesity, antidiabetic and chemopreventive compounds for food-pharma industry; however, further experimental studies are needed to validate its pharmacological properties.

Phytochemical screening, antioxidant properties, and photo-protective activities of Salvia balansae de Noé ex Coss

Abstract The present study evaluated the potential of Salvia balansae from the Aures Mountains as a source of natural bioactive compounds. Leaves, flowers, and stems were extracted separately using methanol, ethanol, and acetone. Phenolic compounds were quantified colorimetrically and identified using liquid chromatography coupled with mass spectrometry (LC-MS). Antioxidant capacity was assessed using six different in vitro assays, 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, 1,1-diphenyl-1-picrylhydrazyl, cupric reducing antioxidant capacity, ferric reducing antioxidant power, ferrous ion chelating, and phenanthroline assay, while the photo-protective capacity was evaluated using the sun protective factor. The methanolic flower extracts revealed the highest O-diphenol and phenolic levels (287.9 ± 0.50 and 147.87 ± 0.21 µg GAE/mg, respectively), whereas the acetonic and ethanolic leaf extracts contained the highest flavonoid (72.17 ± 0.12 μg QE/mg) and flavonol (35.28 ± 0.05 μg QE/mg) levels, respectively. LC-MS was used to identify 18 phenolics, including quinic acid (5.051–69.69 ppm), luteolin-7-o-glucoside (7.802–44.917 ppm), apigenin-7-o-glucoside (3.751–68.507 ppm), and cirsiliol (2.081–15.608 ppm), distinguishing this Aures taxon. Principal component analysis and unweighted pair-group method with arithmetic mean revealed variability in phytochemicals, antioxidant properties, and photo-protective activity influenced by biological activities and the compound content. Overall, S. balansae demonstrated promising photo-protective capacity, the presence of key bioactive compounds, and wide-ranging antioxidant potential, presenting this endemic plant as a valuable source of natural antioxidants and photo-protective agents with pharmaceutical and cosmetic applications.

Characterization of multilayer bacterial cellulose-chitosan films loaded with grape bagasse antioxidant extract: Insights into spectral and water properties, microstructure, and antioxidant activity

This work explores the development and characterization of composite multilayer films comprising bacterial cellulose (BC) and chitosan enriched with antioxidant compounds from grape bagasse extract (GE) and glycerol. SEM images revealed a compact structure with successful interactions between BC and chitosan, confirmed by FT-IR analysis. Equilibrium moisture content, water vapor permeability (WVP), swollen capacity, and solubility were systematically investigated, unveiling the influence of glycerol and GE concentrations. Moisture content increased with elevated glycerol and GE levels, attributed to their hydrophilic nature. WVP rose with higher concentrations of hydrophilic compounds, affecting the films' permeability. Swollen capacity decreased, and solubility increased with the addition of GE and glycerol, indicating a more compact film structure. The incorporation of GE conferred antioxidant properties to the films, as evidenced by DPPH and ABTS+ assays, and Total Phenolic Content (TPC) determination. TPC values varied from 0 to 1.75 mg GAE/g dried film, depending on GE. Fourier Transform Infrared Spectroscopy (FT-IR) highlighted polymeric associations, and UV–Vis spectra demonstrated enhanced UV-blocking properties. Overall, these multilayer films offer promising applications in food packaging, leveraging natural antioxidant sources for an enhanced functionality.

The forgotten fruit (Cydonia oblonga Mill.) and its chemical composition: a review

AbstractNatural plant sources, particularly the fruits of several lesser-known species, are receiving increasing amounts of attention because they contain a variety of bioactive compounds that are advantageous to human health. The production of easy-to-grow, already-used, and full of nutrients crops could be a solution to the growing problem of a lack of healthful food. One such fruit is the quince (Cydonia oblonga Mill.), which belongs to the Rosaceae family that originated in the Caucasian area and extends to other parts of the world. Quince has been studied for decades because of its unique importance in food and medicine. The characteristic pear-shaped fruit is golden yellow in appearance and has an aromatic, and acidic flavour. The low-fat fruit is rich in numerous necessary nutrients, minerals, dietary fibre, and antioxidants that have significant positive effects on health, but due to its bitterness, it is underutilized. Quince can be utilised as a raw material to create a variety of food products and is a good source of natural phenolic antioxidants, providing significant functional characteristics.

Design of three-component essential oil extract mixture from Cymbopogon flexuosus, Carum carvi, and Acorus calamus with enhanced antioxidant activity

The development of novel antioxidant compounds with high efficacy and low toxicity is of utmost importance in the medicine and food industries. Moreover, with increasing concerns about the safety of synthetic components, scientists are beginning to search for natural sources of antioxidants, especially essential oils (EOs). The combination of EOs may produce a higher scavenging profile than a single oil due to better chemical diversity in the mixture. Therefore, this exploratory study aims to assess the antioxidant activity of three EOs extracted from Cymbopogon flexuosus, Carum carvi, and Acorus calamus in individual and combined forms using the augmented-simplex design methodology. The in vitro antioxidant assays were performed using DPPH and ABTS radical scavenging approaches. The results of the Chromatography Gas-Mass spectrometry (CG-MS) characterization showed that citral (29.62%) and niral (27.32%) are the main components for C. flexuosus, while d-carvone (62.09%) and d-limonene (29.58%) are the most dominant substances in C. carvi. By contrast, β-asarone (69.11%) was identified as the principal component of A. calamus (30.2%). The individual EO exhibits variable scavenging activities against ABTS and DPPH radicals. These effects were enhanced through the mixture of the three EOs. The optimal antioxidant formulation consisted of 20% C. flexuosus, 53% C. carvi, and 27% A. calamus for DPPHIC50. Whereas 17% C. flexuosus, 43% C. carvi, and 40% A. calamus is the best combination leading to the highest scavenging activity against ABTS radical. These findings suggest a new research avenue for EOs combinations to be developed as novel natural formulations useful in food and biopharmaceutical products.

Bioactive metabolite profiles and quality of Rosa rugosa during its growing and flower-drying process

Rosa rugosa is extensively cultivated in China for its remarkable fragrance and flavor, however, the metabolic changes in roses during growth and drying remain unclear. Our results revealed significant variations in phenol and flavonoid contents and antioxidant capacity in roses (Rosa rugosa f. plena (Regel) Byhouwer) under different conditions. Phenol contents were positively correlated with antioxidant capacity, with phytochemicals being most prominent in unfolded petals. The highest antioxidant capacity and phenol and flavonoid contents were observed in April. Considering their greater consumption value, whole flowers were more suitable than petals alone. Furthermore, considerable sensory and nutritional differences were observed in dried roses. Different drying methods increased their total phenol content of roses by 4.2–5.4 times and the antioxidant capacity by 2.9 times. Metabolomics revealed the altered contents of flavonoids, anthocyanins, lipids, amino acids, and saccharides. This study provides baseline data for the potential of roses as a natural source of antioxidants in the food and pharmaceutical industries.

Physicochemical composition, centesimal, and phytochemical profile of umbu seed flour (Spondias tuberosa Arruda)

This study aimed to investigate the nutritional potential of umbu (Spondias tuberosa Arruda) seed flours. This was an experimental study. The seeds of the umbu fruit were subjected to an oven-drying process in order to obtain the flour. Subsequently, the analysis of the centesimal composition, physicochemical, mineral, and fatty acid profile, microbiological investigation, and the screening of bioactive phytochemicals of the umbu seed flours in hydroethanolic extracts were carried out. A completely randomized design (CID) was used, with three replications, and the results were expressed as means followed by standard deviation. Analysis of variance (ANOVA) was carried out, and the Tukey’s test was applied at a 5% probability level. It was possible to obtain flour from umbu seeds. It was observed that they contained significant amounts of insoluble dietary fiber (80.9 ± 0.55a g.100-1), protein (6.95 ± 0.10a g.100-1), and lipids (5.54 ± 1.13a g.100-1). The minerals present included zinc (1.87 ± 0.05b mg.100 g-1), manganese (14.36 ± 0.34c mg.100 g-1), and calcium (104.79 ± 0.92c mg.100 g-1). The flours had high levels of oleic monounsaturated fatty acids (33.10 ± 0.13a g.100-1), linoleic polyunsaturated fatty acids (38.06 ± 0.06b g.100-1), and palmitic saturated fatty acids (19.1 ± 0.04b g.100-1), in addition to considerable levels of phenolic compounds (276.21 ± 14.01a mg.g-1 GAE) and flavonoids (891.09 ± 9.01ª mg.g-1 rutin), with satisfactory sanitary conditions for Escherichia coli, Salmonella, Bacillus cereus molds, and yeasts. This study suggests that umbu seed meals can be considered relevant sources of dietary fiber, minerals, and natural antioxidants.

Antioxidant potential of alkaloids and polyphenols of Viola canescens wall using in vitro and in silico approaches.

Background: V. canescens Wall, a plant renowned for its ethno-medical properties, was investigated in this study for its antioxidant potential based on its wide therapeutic applications in traditional healthcare systems. The study aimed to assess the antioxidant potential of the plant extract/fractions and to predict the active phytochemicals using computational techniques. Methods: Five fractions were obtained from the crude methanolic extract of Viola canescens, and six concentrations (25, 50, 75, 100, 125, and 150μg/mL) were prepared for each fraction. The antioxidant activity of these fractions was evaluated using the Tetraoxomolybdate (VI) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. In-silico docking studies and molecular dynamic simulations were conducted to further elucidate the molecular interactions underlying the antioxidant activity. Results: The aqueous extract of V. canescens exhibited significant antioxidant and free radical scavenging activity against DPPH. Additionally, the crude flavonoid extract demonstrated moderate activity with IC50 value of 57.863μg/mL, indicating potent inhibition of cell growth. In-silico docking studies revealed a strong interaction between emetine and the aromatase protein, suggesting its potential as an antioxidant. Conclusion: The study findings highlight the antioxidant potential of V. canescens extract, indicating its suitability as a source of natural antioxidants. These results suggest its potential application in pharmaceutical preparations aimed at harnessing antioxidant properties for therapeutic purposes.

Chemical Profile and Biological Activities of Brassica rapa and Brassica napus Ex Situ Collection from Portugal.

This study aimed to analyse the chemical profile and biological activities of 29 accessions of Brassica rapa (turnips) and 9 of Brassica napus (turnips and seeds) collections, maintained ex situ in Portugal. HPLC-HRMS allowed the determination of glucosinolates (GLS) and polyphenolic compounds. The antioxidant and antimicrobial activities were determined by using relevant assays. The chemical profiles showed that glucosamine, gluconasturtiin, and neoglucobrassin were the most abundant GLS in the extracts from the turnip accessions. Minor forms of GLS include gluconapoleiferin, glucobrassicanapin, glucoerucin, glucobrassin, and 4-hydroxyglucobrassin. Both species exhibited strong antioxidant activity, attributed to glucosinolates and phenolic compounds. The methanol extracts of Brassica rapa accessions were assessed against a panel of five Gram-negative bacteria (Enterobacter cloacae, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica subsp. enterica serovar, and Yersinia enterocolitica) and three Gram-positive bacteria (Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus). The extracts exhibited activity against S. enterica and S. aureus, and two showed inhibitory activity against E. coli and Y. enterocolitica. This study provides valuable insights into the chemical composition and biological properties of Brassica rapa and Brassica napus collections in Portugal. The selected accessions can constitute potential sources of natural antioxidants and bioactive compounds, which can be used in breeding programs and improving human health and to promote healthy food systems.

Antimicrobial secondary metabolites and antioxidant activities of fungal endophytes associated with Ziziphus spina-christi (L.) Desf. (Nabq) leaves

A total of 20 endophytic fungi were isolated (ZSEFL1-ZSEFL20) from Ziziphus spina-christi (L.) Desf. (Nabq) leaves. Four isolates A2/ZSEFL2, Alternaria alternata, D/ZSEFL14, Aspergillus niger, E/ZSEFL15, Epicoccum nigrum, and S/ZSEFL19, Penicillium crustosum were found to show the most promising antimicrobial activities either in plug or disc diffusion screening assays against Gram-positive, Gram-negative bacteria and pathogenic fungi. Antimicrobial activity was tested against Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 29213, Serratia marcescens ATCC 14764, Klebsiella pneumoniae ATCC 700603, Candida albicans ATCC 10231, and Fusarium oxysporum ATCC417. In vitro antioxidant activity assay was conducted using the ABTS [2,2′-Azino-bis (3-Ethylbenzthiazoline-6-Sulfonic Acid)] free radical scavenging method. EtOAc extracts of all isolated endophytic fungi showed antioxidant activities. This study would be one of the first reports to measure the antioxidant activity of Z. spina-christi (L.) Desf. endophytic fungi. Therefore, these isolated endophytic fungi can provide additional information for medicinal sources of natural antioxidants and antimicrobial agents.

Comparative antioxidant activity of Sesame root and leaf extract - An In-vitro study

Universe has millions and millions of plants, but not all the plants have medicinal values.  One such gift from nature is Sesame and is crowned as the “Queen of oilseed crops” due to its various medical properties like anti-inflammatory, antioxidant, anti- microbial etc. This research paper aims to compare the antioxidant activity of sesame leaf extract and sesame root extract with the standard ascorbic acid using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide (H2O2) assay. Different concentrations of the extracts and ascorbic acid were prepared (10 µg/mL, 20 µg/mL, 30 µg/mL, 40 µg/mL, and 50 µg/mL), and the antioxidant activity was measured. The results indicate that both sesame leaf extract and sesame root extract exhibit antioxidant activity, with sesame leaf extract showing slightly higher activity than sesame root extract. The findings suggest that sesame leaf extract has potential as a natural antioxidant source and could be used as an alternative to synthetic antioxidants. Overall, this study provides valuable information on the potential health benefits of sesame extracts and highlights the importance of natural antioxidants in preventing free radical damage and associated diseases.

The effect of extraction method on biological activity and phytochemical content of Artocarpus heterophyllus (jackfruit) leaves extract concurrent with its principal component analysis

Artocapus heterophyllus (jackfruit) is available in abundance in tropical regions. The present study explored the effect of different extraction method i.e. maceration, ultrasonication and both of ultrasonication and maceration on its biological activity (antioxidant, antidiabetes and antibacterial activities) and phytochemical content of Artocarpus heterophyllus (jackfruit) leaves extract. Jackfruit leaves were extracted using ethanol as solvent. The capability of jackfruit leaves extract to scavenge radicals was evaluated using a DPPH (2,2-diphenyl-1-picryl-hydrazyl) assay, β-carotene bleaching assay and reducing power assay. The total phenolic content (TPC) was assessed using the Folin- Ciocalteau method. Its antibacterial activity was assessed using the disc diffusion and microdilution method against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhimurim and Escherichia coli. The α-glucosidase inhibitor assay was conducted using α-glucosidase from Saccharomyces cerevisiae. The results revealed that ulrasonication method give the highest antioxidant activity in three metode used, i.e. DPPH assay with IC50 of 42.51µg/mL, β-carotene bleaching assay of 57.64%, reducing power assay of 919mg GAE/g. Meanwhile, for α-glucosidase inhibitory assay, ultrasonication method also had the highest value of 83.44% at concentration of 1000µg/mL. Furthermore, antibacterial assay using disk diffusion method showed ultrasonication had the highest inhibition zone of 7.81mm at 5mg/mL against P. aeruginosa, while maceration method had the highest inhibition zone of 8.02mm at 5mg/mL against E. coli. These results in accordance with total phenolic content (TPC) of ultrasonication extract which was the highest of 125.06mg GAE/g. The liquid chromatography-high-resolution mass spectrometry (LC-HRMS) analysis suggested that several bioactive compounds such as phenolic, flavonoid and its derivatives was present in the jackfruit leaves extract. Further analysis using principal component analysis (PCA) revealed that the extraction process affected the metabolite composition of the samples which was confirmed by significant separation of the score plots of extraction methods. The present study revealed that jackfruit leaves is a potent source of natural antibacterial, antioxidants and antidiabetic medicines in functional foods and pharmaceutical industries.

Extraction and Characterization of Natural Antioxidants from Olive Leaves Powder

Olive (Olea europaea L.) leaves, which contain large amounts of phenols, are a common byproduct in the production of olive oil. When improperly processed, the by-products produced by the olive diligence can impairment the environment. Its leaves, which are made when olive trees are pruned and harvested and it is expected that foliage make up twenty five percent of pruning remains overall. These byproducts cost manufacturers money and have serious environmental implications. So, like other agronomical production wastes, partial reuse is something that should be pursued. These leftovers have a high concentration of beneficial chemicals, if isolated, may be used in food, cosmetics and nutraceutical sectors. Objectives: To extract the bioactive compounds polyphenols and flavonoids in 70% ethanol extract and its antioxidant activity was done. Methods: The polyphenols were quantified by Folin reagent and flavonoids by aluminum chloride methods respectively and the natural antioxidants were estimated by using free radical scavenging DPPH assay. Results: It was discovered that the 70% ethanol extract's total polyphenolic content was 65.50 ± 1.42 (mg GAE/g) and its total flavonoids were 11.85 ± 0.60 (mg QE/g). In 70% ethanol extract the % inhibition (DPPH) was 42.82±3.20-88.40±5.18 while BHT has the % inhibition (DPPH) 30.4 ± 2.50-80.50 ± 4.68 at concentration 0.1-0.5 mg/ml. Conclusions: The results indicating a noteworthy antioxidant activity in terms of radical scavenging activity. These results also wrapped up that the olive industry waste may be reutilized as a natural source of antioxidants in various sectors. 

Antioxidant activity and phytochemical analysis of aqua-ethanol extract of Bauhinia racemosa Lam. leaves

The objectives of this study were to evaluate antioxidant activity, qualitative phytochemical analysis and LC-MS/MS analyses of aqua-ethanol extract of Bauhinia racemosa Lam. plant leaves. The extract afforded the rich content of different phytochemicals reported in qualitative phytochemical analysis, LC-MS/MS spectral analysis the leaves and antioxidant activity pharmacological activity. The extract was subjected to assess their antioxidant potential using DPPH in vitro system. Using DPPH (2, 2-Diphenyl-1-picrylhydrazyl) free radical scavenging assay, the aqua-ethanol extract was found to have significant antioxidant activity with an IC50 value 42.17 ± 0.03 mg/mL. A qualitative phytochemical analysis shows that the plant leaves contains carbohydrate, protein, amino acids, glycoside, tannins, saponin, flavonoids and phenolic compounds. It is concluded that the aqua-ethanol extract of Bauhinia racemosa Lam. leaves have been strong antioxidant potential. Further study is needs for isolate and characterizes the active antioxidants, which may serve as a potential source of natural bioactive antioxidants.

Exploring the Chemical Profile, In Vitro Antioxidant and Anti-Inflammatory Activities of Santolina rosmarinifolia Extracts.

In this study, the phytochemical composition, in vitro antioxidant, and anti-inflammatory effects of the aqueous and 60% ethanolic (EtOH) extracts of Santolina rosmarinifolia leaf, flower, and root were examined. The antioxidant activity of S. rosmarinifolia extracts was determined by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. The total phenolic content (TPC) of the extracts was measured by the Folin-Ciocalteu assay. The anti-inflammatory effect of the extracts was monitored by the Griess assay. The chemical composition of S. rosmarinifolia extracts was analysed using the LC-MS technique. According to our findings, 60% EtOH leaf extracts showed the highest Trolox equivalent antioxidant capacity (TEAC) values in both ABTS (8.39 ± 0.43 µM) and DPPH (6.71 ± 0.03 µM) antioxidant activity assays. The TPC values of the samples were in good correspondence with the antioxidant activity measurements and showed the highest gallic acid equivalent value (130.17 ± 0.01 µg/mL) in 60% EtOH leaf extracts. In addition, the 60% EtOH extracts of the leaves were revealed to possess the highest anti-inflammatory effect. The LC-MS analysis of S. rosmarinifolia extracts proved the presence of ascorbic acid, catalpol, chrysin, epigallocatechin, geraniol, isoquercitrin, and theanine, among others, for the first time. However, additional studies are needed to investigate the direct relationship between the chemical composition and physiological effects of the herb. The 60% EtOH extracts of S. rosmarinifolia leaves are potential new sources of natural antioxidants and anti-inflammatory molecules in the production of novel nutraceutical products.

Extraction, Estimation and Utilization of Curry Leaf (Murraya koenigii) Stalks as a Potential Source of Antioxidants

Background: Processing wastes that are generated at industrial and house hold level are a huge concern. Utilization of these by-products and their bioactive compounds is a blooming industry at present. This study has been designed to unleash the potential of such by-product (stalks) and their possible application. Methods: In order to use plant by-products as a potential source of antioxidants, the methanolic, aqueous methanolic and aqueous extracts of the curry leaf stalks were studied. The nutrient, anti-nutrient, phytochemical content and in-vitro antioxidant activities were assessed for the stalks. The plant extracts were then incorporated in sunflower oil and tested for stability of oil upon repetitive deep frying. Result: Total phenolic content and flavonoids followed the order of aqueous methanolic greater than aqueous greater than methanolic extracts. The phytochemical analysis of the extracts for total flavanols followed the order aqueous greater than aqueous methanolic greater than methanolic. In vitro antioxidant activities of the extracts in DPPH, FRAP, reducing power and CUPRAC assays followed the order aqueous methanolic greater than methanolic greater than aqueous extracts. Therefore, aqueous methanol is a suitable solvent among the three solvents for extracting most active components with higher antioxidant activity from the stalks. Findings from the present study infer that Curry leaf stalks can be a potential source of natural antioxidants and can be used in foods and pharmacological formulas.

Dietary plant flavonoid supplementation for poultry as a potent scavenger of hydroxyl radicals and antioxidants: a review

The poultry industry is paying more attention to plant-based feed additives. Flavonoids are plant secondary metabolites derived from fruits, grains, vegetables, herbs, and medicinal plants. One of the most significant environmental stressors affecting the poultry industry worldwide is heat stress, which lowers the quality and safety of production. An imbalance between the production of free radicals and the body’s natural antioxidant defenses leads to oxidative stress in cells. These reactive species can damage proteins, lipids, DNA, and cellular structures. Improving the antioxidant status of poultry bodies by feeding them antioxidant-supplemented feed can increase productivity and health. Plant flavonoid compounds have drawn attention from researchers as possible natural antioxidant sources because of their potential for use as feed additives in poultry production. Numerous studies have demonstrated that dietary flavonoids have strong antioxidant effects and can be utilized as a tonic in poultry to improve health and productivity. Overall, research on the antioxidant capacity of plant flavonoids has generally shown promising results; however, there are still significant issues regarding the detrimental effects of flavonoids to be resolved, and measuring oxidative damage in vivo is challenging. This review summarizes the current understanding of dietary plant flavonoid supplementation for poultry as a potent scavenger of hydroxyl radicals and antioxidants.

In Vitro Test of Antioxidant Activity of Leilem Leaf Ethanol Extract (Clerodendrum minahassae) Using DPPH and FRAP Methods

The risk of degenerative diseases is increasing due to unhealthy lifestyles. Many people consume junk food, smoke, and do not protect themselves from sun exposure and pollution, exposing their bodies to free radicals. Free radicals can cause oxidative stress, necessitating the need for antioxidants to neutralize them. The leilem plant (Clerodendrum minahassae) is an endemic plant from North Sulawesi that is often used in traditional dishes and medicine. Moreover, leilem leaves are believed to be a source of natural antioxidants. This study aimed to determine the efficacy of leilem leaf ethanol extract as a source of antioxidants. The antioxidant potential was evaluated using phytochemical screening and antioxidant assays such as 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) and Ferric Reducing Antioxidant Power (FRAP) methods, with ascorbic acid as a comparison. The level of antioxidant activity was measured by determining the IC50 value, which corresponds to the concentration of extract required to inhibit 50% of free radicals. The results of phytochemical screening showed that the ethanol extract of leilem (Clerodendrum minahassae) leaves contains active compounds such as phenols, flavonoids, saponins, tannins, steroids/triterpenoids, and alkaloids, indicating a high potential for antioxidant activity. The IC50 value for the DPPH method was 78.799 ppm, and the IC50 value for the FRAP method was 92.127 ppm. These results demonstrate that the ethanol extract of leilem leaves has strong antioxidant activity in both the DPPH and FRAP methods.

Characterization and antioxidant activity of peel extracts from three varieties of citrus sinensis

High volume of postharvest materials including peels from citrus fruits is periodically generated, which contributes to environmental pollution. Investigating the chemical composition cum antioxidant property of these ‘wastes’ would be instructive in achieving value addition in the food and pharmaceutical value chain. On this premise, this study carried out phytochemical screening and antioxidant activity of three (3) commonly cultivated citrus varieties namely Citrus sinensis ‘valencia’, Citrus sinensis ‘washinton’ and Citrus sinensis ‘thompson navel’. The peels were extracted using ethanol and hexane in a Soxhlet extractor and thereafter subjected to phytochemical and Gas Chromatography/Mass Spectrometry (GC/MS) analyses, ferric ion reducing antioxidant power (FRAP), hydrogen peroxide scavenging and cupric ion reducing antioxidant capacity (CUPRAC) assays to evaluate their antioxidant potentials. Results show that Citrus sinensis peel extracts contain alkaloids, flavonoids, phenols, phytosterols, diterpenes, tannins and glycosides. GC/MS analysis identified about 48 compounds in each extract; with the predominant bioactive compounds being limonene (16.5%), ascorbic acid (17.7%), stearic acid (26.3%), linalool (4.7%), linoleic acid (16.18%), palmitic acid (15.23%), pentadecyclic acid (1.1%). Ethanol and hexane extracts of Valencia exhibited higher FRAP (9.09 ± 0.13) and CUPRAC (2.04 ± 0.06) values while the ethanol extract of Ibadan sweet demonstrated greater hydrogen peroxide scavenging activity (1.39 ± 0.00). Citrus peels are rich in bioactive compounds with excellent antioxidant activity and may serve as potential sources of natural antioxidants for food products or pharmaceutical formulations.

Effect of regional disparities and solvent variations on the phenolic composition, antioxidant activity, and antibacterial efficacy of Cupressus sempervirens extracts

ABSTRACT The ethyl acetate, ethanol, methanol, and water extracts of cypress from three Tunisian regions (Bizerte, Ben Arous, and Nabeul) were reported for their phenolic content, antioxidant, and antibacterial activities. Cypress extract had an important antiradical and antibacterial potential which was strongly related to the organoleptic quality of the extract which appeared strongly region dependent. The highest contents of polyphenols were obtained in the methanol extract at the region of Bizerte (315.75 mg GAE/g DW). Cupressuflavone was the major compound with high proportions in methanol extract of Bizerte (68%). Amentoflavone also constituted an important flavonoid compound presented in higher proportion in the ethyl acetate extract of Ben Arous (21.2%). For Gram-positive bacteria strains, Staphylococcus aureus was sensitive to the ethanol extract of Nabeul with IZ = 40 mm. This study suggests cypress as potential natural source of antioxidants and antibacterial agents.