Determined Using 2,2-diphenyl-1-picrylhydrazyl Research Articles

Comparative Study of Antioxidant and Antibacterial Activities of Tropical Citrus Fruits (Juice and Peels)

Tropical citrus fruits contain important bioactive compounds with health-promoting properties such as antioxidant and antibacterial properties. This study provided comparative data on the antioxidant and antimicrobial activity of tropical citrus (local lemons, imported lemons, and limes) juice and peel. Antioxidant activity of citrus fruits was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and expressed as IC50. Antimicrobial activity was evaluated against pathogens (E. coli, B. subtilis, S. aureus) using agar diffusion method. The results showed that very strong antioxidants were detected in domestic and imported lemon juice (33.45 ppm; 31.43 ppm) and peel (15.89 ppm; 44.50 ppm). However, lime juice and peel had stronger antioxidant activity (60.35 ppm and 59.54 ppm). The highest zone of inhibition was observed against S. aureus and the lowest was recorded against E. coli. The diameters of the zones of inhibition of local lemon, imported lemon, and lime juice against S. aureus were 26.40 mm, 27.95 mm, and 27.31 mm; E. coli was 15.64 mm, 16.84 mm, and 16.63 mm; and B. subtilis was 17.88 mm, 21.77 mm, and 21.24 mm, respectively. Tropical citrus juice showed higher activity against Grampositive than Gram-negative bacteria tested. Local lemon, imported lemon, and lime peels did not inhibit E. coli, B. subtilis, and S. aureus. Keywords: Antibacterial, Antioxidant, Lemon, limes, Tropical citrus

Antioxidant Activities of Stem, Leaves and Fruits Extracts of Pepino (Solanum muricatum Aiton).

<b>Background and Objective:</b> Pepino (<i>Solanum muricatum</i> Aiton), rich with vitamin C and flavonoids, constitutes an abundant source of potent antioxidants. This research was conducted to determine antioxidant activity from three different parts of pepino based on equivalence with ascorbic acid, to analyze the relationship between total phenolic content (TPC) and total flavonoid content (TFC) on antioxidant activities and to determine flavonoid compounds. <b>Materials and Methods:</b> Antioxidant activities were determined using 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) and Cupric Ion Reducing Antioxidant Capacity (CUPRAC) methods. The TPC and TFC were determined by UV-visible spectrophotometry. The correlation between TPC, TFC and antioxidant activity was analyzed using Pearson's method. Flavonoid compound content was performed by HPLC. <b>Results:</b> The ethyl acetate pepino fruit extract expressed the highest antioxidant activity by DPPH and CUPRAC assays. The highest TPC was obtained from the ethyl acetate extract of pepino stem (18.493 g GAE/(100 g)), while the highest TFC was obtained from the hexane extract of pepino leaves (9.541 g QE/(100 g)). <b>Conclusion:</b> The DPPH and CUPRAC assays demonstrated that pepino exhibits potential as a source of natural antioxidants, especially in its fruit part.

Chemical Composition and Antioxidant Potential of Leaf Essential Oils of Ocimum Canum Sims Harvested at Various Times Daily

Fresh Ocimum canum leaves were harvested five times at interval of three hours in a twelve hour-cycle daily (7:00, 10:00, 13:00, 16:00, and 19:00 hours). The leaves from each harvest were separately subjected to hydrodistillation for three hours in a Clevenger-type apparatus. The oils obtained were analyzed by Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC-MS). Cluster analysis was used (based on the data, select variables > 0.2% of 43 oil components from five harvest times) to classify the oils. Antioxidant potential of the oils were determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and Sodium Nitroprusside (SNP)-Induced Lipid Peroxidation assays. The oils afforded yield in the range of 0.15-0.23% (w/w), with the highest and lowest yields observed at 7:00 and 13:00 hours respectively. A total of 23-40 compounds, representing 99.4-99.8% of the total oils were identified from their mass spectra with predominance of oxygenated monoterpenoids (50-65.7%), hydrogenated monoterpenoids accounted for 5.4-19.1%, whereas hydrogenated sesquiterpenoids constituted between 10.1-21.4% of the total oils. The most abundant compound was linalool (46.7-52.4%), other major compounds identified were terpinen-4-ol (8.5-9.5%), eugenol (1.9-10%) and trans-α-bergamotene (5.5-10.2%). Cluster analysis revealed a significant variability within the oil samples obtained from various harvest times. The oils presented a considerable antioxidant activity (IC50 of 5.45-10.87µg/ml compared with 4.05-6.11µg/ml for BHT standard) for DPPH assay; and (3.86- 5.36 µg/ml compared with 2.12-4.33 µg/ml for BHA standard) for SNP-Induced lipid peroxidation assay. The oil obtained from 10:00 hours harvest had the best antioxidant activity at IC50 for both assays. Chemical composition and antioxidant activity of the oils varied significantly with harvest times. The oils exhibited antioxidant property comparable to those of standards, hence could serve as cheaper and safer alternative to synthetic drugs to ameliorate oxidative stress after clinical trials.

Investigation of in vitro antidiabetic and antioxidant activity of hawthorn vinegar obtained from Endemic Crataegus tanacetifolia (Poir.) Pers.

In this study, the in vitro antidiabetic, antioxidant activity and total flavonoid content (TFC) and total phenolic content (TPC) of vinegar obtained from endemic Crataegus tanacetifolia (Lam.) Pers. (Rosaceae), (hawthorn) were examined. The hawthorn vinegar obtained from Malatya province (MS) and the vinegar (TS) obtained from Konya were used as study material. Their antidiabetic activity was determined by α-amylase and α-glucosidase inhibitory methods. Antioxidant activities were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and ferrous iron chelating (FCA) assays. The absorbance were read in the Elisa reader and evaluated with Excel and GraphPad programs. The MS has been found to have higher α- amylase (95.12± 3.71%) and α-glucosidase inhibitory (81.62 ± 0.33%) effects. The TS demonstrated (94.13 ± 3.85%) α-amylase and (75.35 ± 2.19%) α-glucosidase inhibitory activity, respectively. The TPC was found to be in TS (467.59 ± 6.73) mg GAE/mL MS (328.46 ± 5.50) mg GAE/mL. The TFC was found as (1.94 ± 10.36) mg CE/mL and (1.32 ± 10.96) mg CE/mL in TS and MS vinegar, respectively. The FCA was found to be in TS (33.37 ± 0.53%) MS (31.08 ± 10.87%). The DPPH radical scavenging activity was found as (73.82 ± 2.12%) in TS and (80.12 ± 4.45%) in MS. ABTS radical scavenging activity was found to be the highest in TS with (82.51± 0.78%) and in MS found as (78.65 ± 0.55%). The antidiabetic, antioxidant activity, TPC and TFC determinations of these vinegars were performed for the first time with these methods.

Eucalyptus torquata L. flowers: a comprehensive study reporting their metabolites profiling and anti-gouty arthritis potential

Gouty arthritis is one of the most common metabolic disorders affecting people. Plant based drugs can lower the risk of this health disorder. The anti-gouty potential of Eucalyptus torquata flowers methanol extract (ETME) was evaluated in vitro via measuring the inhibitory effects of five pro-inflammatory enzymes; xanthine oxidase (XO), hyaluronidase, lipoxygenase (5-LOX), cyclooxygenases COX-1, and COX-2, in addition to evaluating the inhibition of histamine release, albumin denaturation, membrane stabilization, tyrosinase, and protease inhibitory activities. Also, its antioxidant potential was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assays and ferric reducing power assay (FRAP). HPLC–PDA-MS/MS was used to identify the metabolites in the tested extract. The latter exhibited substantial anti-arthritic properties in all assays with comparable potential to the corresponding reference drugs. HPLC–MS/MS analysis of this bioactive extract tentatively annotated 46 metabolites including phloroglucinols, gallic and ellagic acids derivatives, terpenes, flavonoids, fatty acids, and miscellaneous metabolites. Our study highlights the medicinal importance of E. torquata as an anti-gouty candidate and opens new avenues of gouty management.

Wild Mushrooms: Potential Natural Sources of Antioxidant and Anti-Quorum Sensing Bioactive Compounds for Medical Applications.

This study was aimed at determining the antioxidant, anti-quorum sensing, and in vitro cytotoxic activities of five wild mushroom extracts. Wild mushrooms of Auricularia auricula-judae, Termitomyces umkowaani, Trametes elegans, Trametes versicolor, and Microporus xanthopus were collected from Arabuko-Sokoke and Kakamega National Forests, in Kenya. Specimens were identified and extracted using chloroform (CHL), 70% ethanol (Eth), and hot water (HW) solvents. Antioxidant and cytotoxic activities of the extracts were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Vero cell lines, respectively, while anti-quorum sensing activities were tested against Chromobacterium violaceum. All data were compared using relevant descriptive and inferential statistics at a significance level of p ≤ 0.05. A total of 35 wild mushrooms were collected, identified, and classified into 14 genera. Among screened mycochemicals, fatty acids, flavonoids, polyphenols, and saponins were detected at higher concentrations. The highest free radical scavenging activities of A. auricula-judae, T. umkowaani, T. elegans, and T. versicolor were observed in 70% Eth extract with the percentage values of 76.40 ± 0.12%, 68.40 ± 0.01%, 62.40 ± 0.07%, and 66.40 ± 0.04%, respectively, whereas the HW extract of Microporus xanthopus showed free radical scavenging activity at 65.90 ± 0.02%. None of the extracts, at the tested concentrations (up to 1000 µg/mL), had shown cytotoxic activity against the Vero cell line. The HW extract of T. umkowaani and the 70% Eth extract of T. versicolor showed a statistically significant difference in the inhibitory activity of violacein production against C. violaceum at the concentration of 200 µg/mL. The antioxidant activity of wild mushrooms can help to tackle the diseases caused by free radicals. The anti-quorum sensing potential of wild mushrooms could also provide future alternatives to conventional drug therapies cost-effectively. Further detailed chemistry of the bioactive compounds and their possible mechanisms of action responsible for the observed antioxidant and anti-quorum sensing activities are needed.

Green Synthesis of Zinc Oxide Nanoparticles Using Chamomile and Green Tea Extracts and Evaluation of Their Anti-inflammatory and Antioxidant Activity: An In Vitro Study.

Background An important field of study in contemporary material science is the synthesis of metallic nanoparticles. The wide range of uses for zinc nanoparticles in industries like diagnosis and antimicrobial catalysis has sparked particular interest in them. Plant extracts are used to synthesize zinc nanoparticles, opening up a wide range of potential applications. Hence, the current study aims to demonstrate the anti-inflammatory and antioxidant activity of zinc oxide nanoparticles mediated by green tea and chamomile tea combination. Materials and methods Leaves of green tea and chamomile tea were combined in a ratio of 1 gram each. To make a 1-molar solution of the extract, the weighted extracts were thoroughly mixed with 100 ml of distilled water in conical flasks. To synthesize nanoparticles, a magnetic stirrer and an orbital shaker were used alternately with an extract of chamomile and green tea, 0.016 g of zinc oxide, and 90 ml of distilled water at 900 rpm. By using an albumin denaturation assay, the synthesized nanoparticles' anti-inflammatory activity was assessed. Bovine serum albumin (BSA) and egg albumin (EA) were the reagents used in the assay. The antioxidant activity of zinc oxide nanoparticles, which is mediated by chamomile and green tea, was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and H2O2 (hydrogen peroxide) radical scavenging assays. An independent sample t-test was done to compare the anti-inflammatory and antioxidant potentials of zinc oxide nanoparticles mediated by green tea and chamomile tea combination and control using SPSS Statistics version 22.0 software (IBM Corp. Released 2013. IBM SPSS Statistics for Windows, Version 22.0. Armonk, NY: IBM Corp.), and any p-value less than 0.05 was considered statistically significant. Results In this study, the anti-inflammatory activity and antioxidant activity were assessed at variable concentrations of the reaction mixture. The combination of chamomile and green tea extracts mediated by zinc oxide nanoparticles at 50μl concentration showed the maximum anti-inflammatory activity and antioxidant activity at 87% inhibition, respectively. Conclusion Both assays successfully demonstrated better anti-inflammatory and antioxidant activity of zinc oxide nanoparticles mediated by chamomile and green tea combination when compared to control and, therefore, could be evaluated as a potential therapeutic agent.

Green Synthesis of Magnetite Nanoparticles Mediated Fumaria officinalis L. Plant as Sustainable and Renewable Adsorbing Materials

Magnetite nanoparticles (Fe3O4) have been utilized to mediate Fumaria officinalis L., a plant known for its rich source of various phytogredients such as diterpenes, nor-diterpenoids, tri-terpenoids, flavonoids, and phenolic acids. These natural compounds act as capping, reducing, and stabilizing agents, offering an affordable and safer approach to synthesize nanoparticles in line with sustainable and eco-friendly concepts, such as green nanoparticles. The cost-effective synthesized nanoparticles were employed to adsorb Pb(II) from an aqueous solution. For investigating the surface characteristics of the adsorbent, a range of techniques were employed, including Field Emission Scanning Electron Microscope (FE-SEM), Fourier Transform Infrared Spectroscopy, and X-ray Diffraction. Fourier Transform Infrared (FT-IR) spectroscopy was specifically applied to discern the functional groups present within the compounds. To optimize the adsorption process and achieve the best removal efficiency (R%), several parameters, including pH, initial concentration, temperature, and contact time, were optimized using the Response Surface Methodology (RSM). The experimental results indicated that the Langmuir isotherm provided a well-fitted model, suggesting a monolayer of Pb(II) capping on the surface of magnetite nanoparticles, with a maximum adsorption capacity of 147.1 mg/g. Moreover, the kinetic findings demonstrated a strong alignment with the pseudo-second-order model. The computed (qe) and observed outcomes associated with the pseudo-second-order kinetic model exhibited a commendable concurrence, underscoring the model’s remarkable precision in forecasting the adsorption mechanism of Pb(II) within the examined parameters. The antioxidant activity and green nanocomposite properties were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and standard analytical methods. The phytochemical profile exhibited a total phenolic content of 596 ± 0.001 mg GAE/g dry weight and a total flavonoid content of 18.25 ± 0.001 mg QE/g dry weight. The DPPH radical’s inhibition showed potent antioxidant activity at various concentrations (44.74, 73.86, 119.791, and 120.16% at 200, 400, 600, and 800 μg/mL, respectively), demonstrating the potential of the plant as a natural capping and reducing agent during the green process of nanoparticle formation.

Antioxidant activity and reduction potential of dietary herbs on acrylamide formation in asparagine-glucose reaction model

ABSTRACT Natural ingredients are increasingly being used to prevent the formation of acrylamide during food processing. This study investigated the antioxidant activities of Ocimum basilicum (basil), Lippia adoensis var. adoensis (kesse), Lippia adoensis var. koseret (koseret), Rosmarinus officinalis (rosemary), and Thymus schimperi (tosign) extracts and their acrylamide reduction effect in the asparagine-glucose model system. Folin-Ciocalteu and aluminum chloride methods were used to calculate the total phenolic content (TPC) and total flavonoid content (TFC). Antioxidant activities were determined using 2,2-Diphenyl-1-Picryl-Hydrazyl (DPPH) scavenging and phosphomolybdenum assay methods. Acrylamide contents of the samples were determined by a reversed phase high-performance liquid chromatography (RP-HPLC-DAD) method. Kesse had the highest concentrations of TPC (30.20 ± 1.23 mg gallic acid equivalent per gram of herb extract), TFC (15.87 ± 0.55 mg catechin equivalents per gram), and the strongest DPPH scavenging activity (IC50 = 108 μg/mL). The amount of acrylamide formed during the frying process was decreased by a factor of 26.8% to 65.81% with the addition of dietary herb extracts to the asparagine-glucose reaction model. The amount of acrylamide formed from an asparagine-glucose reaction model containing herb extracts was negatively correlated with the total phenolic and total flavonoid content with, R2 values of 0.920 and 0.930. This study suggests a potential application of these dietary herb extracts as a natural antioxidant for lowering acrylamide formation during the Maillard reaction in fried food products.

Salvia multicaulis for biosynthesis of antioxidant CuO/SiO2 NCs and assessment of its phytochemical profile

The phytochemical and elemental profile of Salvia multicaulis plant is evaluated for bio-fabrication of [email protected]2 nanocomposite (NCs). The antioxidant activity of plant extract and NCs were also determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. Also, the phytochemical examination of the plant shows some biomolecules such as terpenes, flavonols, keto-enol compounds, aldehydes, proteins, vitamins, nitrogen-containing compounds, alkaloids, and tannins. According to our findings, high phenolic content (438 mg GAE/g dry wt) and flavonoid (252.16 mg QE/g dry wt) in Salvia multicaulis extract exhibited maximum inhibition of DPPH radicals (47.74%, 97.05% and 114.8 % in 50, 800 and 3200 µg/ml), respectively, demonstrating the pontent antioxidants activity due to plant’s phytoconstituent antioxidants.

Health Benefits, Antioxidant Activity, and Sensory Attributes of Selected Cold-Pressed Oils.

The consumption of cold-pressed oils (CPOs) has continuously increased due to their health-promoting compounds, such as polyunsaturated fatty acid (PUFA), tocopherols, sterols, and polyphenols. This study focused on the estimation and comparison of the physicochemical properties and sensory quality of six CPOs: linseed oil (CPLO), pumpkin oil (CPPO), milk thistle oil (CPMTO), rapeseed oil (CPRO), camelina oil (CPCO), and sunflower oil (CPSO), which are the most popular in the Polish market. These oils were analysed for their fatty acid composition (FAC), their tocopherol, sterol, polycyclic aromatic hydrocarbon (PAHs), water, and volatile matter (WVM) contents, as well as their antioxidant activity (AA) and oxidative stability parameters. Moreover, quantitative descriptive analysis (QDA) was performed to obtain detailed information on the sensory profiles and quantitative data on the CPOs' attributes that affected consumer acceptability and purchase intent. All of the analysed CPOs were rich in PUFA (27.94-68.42%). They were characterised by the different total amounts of health-beneficial compounds, such as tocopherols (TTC = 44.04-76.98 mg/100 g), sterols (TSC = 300-684 mg/100 g), and polyphenols (TPC = 2.93-8.32 mg GA/100 g). Additionally, their AA was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) methods, with results ranging between 185.36-396.63, 958.59-1638.58, and 61.93-119.21 µmol TE/100 g, respectively. However, the deterioration parameters of CPOs, such as peroxide values (PV = 0.24-4.61 meq O2/kg), p-anisidine values (pAnV = 0.39-4.77), acid values (AV = 0.31-2.82 mg KOH/g), and impurity amounts (Σ4PAHs = 1.16-8.76 μg/kg and WVM = 0.020-0.090%), did not exceed the level recommended by the Codex Alimentarius Commission. The obtained results indicated that all of the investigated CPOs are valuable sources of health-promoting bioactive compounds.

Enhancement of 6-gingerol extraction from Bentong ginger using supercritical carbon dioxide

Supercritical carbon dioxide extraction is a green technology. It was used to isolate 6-gingerol from Bentong ginger (Zingiber officinale Roscoe var. Bentong). A central composite design (CCD) was employed to investigate and optimize three process conditions, namely the extraction pressure (10–30 MPa), temperature (40–60 °C), and particle size of the sample (300–600 µm). The method was used to model the extraction of 6-gingerol, total phenolic content, total flavonoid content, and antioxidant activity determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH). The optimum conditions were estimated to be a pressure of 25 MPa, a temperature of 40 °C, and a particle size of 300 µm. The highest values for 6-gingerol content (171.26 mg/g), total phenolic content (17.84 GAE mg/g), total flavonoid content (74.46 QE mg/g), and radical-scavenging activity (91.14%) of dried Bentong ginger were achieved at these optimized conditions. The good fit between predicted and experimental values shows the fitness of the model employed for estimating the optimum conditions for Bentong ginger extraction. Moreover, the scCO2 system at the conditions studied was more effective than the conventional Soxhlet method for the extraction of bioactive compounds.

Essential oil composition, antimicrobial and antioxidant properties of Pluchea eupatorioides Kurz collected from Vietnam

Pluchea eupatorioides Kurz, which belongs to the family Asteraceae, is known for its medicinal properties and has been traditionally used to treat various diseases. This study aimed to investigate the chemical composition of the essential oil extracted from the aerial parts of P. eupatorioides and evaluate its antimicrobial and antioxidant activities. The essential oil was isolated by hydrodistillation and analysed by gas chromatography/ mass spectrometry (GC/MS). Thirty-three volatile compounds were identified in P. eupatorioides essential oil, including β-caryophyllene (29.36%), 2,5-dimethoxy-p-cymene (18.41%), α-isocomene (15.74%), and caryophyllene oxide (9.77%) as the major compounds. The antimicrobial activity of P. eupatorioides essential oil was investigated using a broth microdilution assay to determine the minimum inhibitory concentration (MIC). The results indicated that P. eupatorioides essential oil demonstrated effectiveness against Staphylococcus aureus ATCC 25923 and Candida albicans ATCC 10231 with a MIC of 100 µg/mL. Moreover, the essential oil was also found to be effective against Bacillus cereus ATCC 14579 and Escherichia coli ATCC 25922, but with a slightly higher MIC of 200 µg/mL. Furthermore, the antioxidant activity of P. eupatorioides essential oil was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging assays. The IC50 values calculated using the DPPH and ABTS assays were 164.2 and 136.1 µg/ mL, respectively. These findings demonstrate that the P. eupatorioides essential oil could be used as a potential source of antimicrobial and antioxidant agents for the food and pharmaceutical industries. This is the first report describing the chemical compositions, antimicrobial and antioxidant activities of P. eupatorioides essential oil.

Antimicrobial, Phytochemical and Antioxidant Screening of Acalypha fimbriata Leaf Extract for Alternative Antimicrobial Therapy

In folklore, Acalypha fimbriata have been associated with ‘cure all’ properties, but without sufficient empirical ethno-pharmacological scientific backups. This research work is therefore necessitated to determine the antimicrobial, phytochemicals and antioxidant activity of Acalypha fimbriata. The leaf of Acalypha fimbriata were Soxhlet extracted, reconstituted, and screened for phytochemical constituent of antimicrobial importance. Conventional biochemical characterization was carried out on the isolates of Staphylococcus aureus, Escherichia coli Pseudomonas aeruginosa and Klebsiella pneumoniae obtained for the research work and the antimicrobial activity of the plant sample was determined using the agar well diffusion technique. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) of the extract were determined by broth dilution method on the isolates. The antioxidant activity of the extract was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and Graphpad prism were used to interprets the data. Alkaloids, flavonoid, anthraquinones, tannins and saponins was found in the leaf extract. Staphylococcus aureus exhibited highest zone of growth inhibition (28mm) at 100mg/ml while Pseudomonas aeruginosa had the lowest (14mm) at 100mg/ml from the antimicrobial assay. In the determination of the minimum inhibitory concentration and minimum bactericidal concentration, Staphylococcus aureus exhibited MIC and MBC at 0.625µg/ml and 12.5 µg/ml, while Pseudomonas aeruginosa elicited MIC and MBC at 10 µg/ml and >10 µg/ml of MIC and MBC respectively. Themethanol extract of the plant acted as hydrogen/electrons donor or scavenger of radicals with fifty percent inhibitory concentration (IC50) of 59.83 µg/ml while that of Ascorbic acid (standard) was found to be 92.70 µg/ml using. The varied MIC’s and MBC’s obtained coupled with the values recorded for the antioxidant radicals validate the antimicrobial and antioxidant potential of Acalypha fimbriata that can be explored for therapeutic option, if further purified and optimally processed.

Anti-tyrosinase, anti-skin pathogenic bacterial, and antioxidant activities and phytochemical constituents of Dracaena cochinchinensis (Lour.) S.C. Chen extract

Dracaena cochinchinensis (Lour.) S.C. Chen (Chandaeng) is an important traditional medicinal plant used in ancient Thai household remedies. This research focused on investigating the biological properties, including the antibacterial, anti-tyrosinase, antioxidant activities, and phytochemical characteristics of crude Chandaeng extracts. Dried Chandaeng heartwood powder was extracted using ethanol, methanol, and deionized water. The antibacterial activities of the extracts were then tested against skin pathogens, including Cutibacterium acnes (DMST14916), Staphylococcus epidermidis (TISTR518), and Staphylococcus aureus (TISTR321). The ethanolic extract showed antibacterial activity. In a time-kill assay, all bacteria were completely killed after being exposed to it, while the cell membranes were found to have leaked when viewed under a scanning electron microscope. Antioxidant potential was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2¢-azino-bis -3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. According to the findings, the crude ethanolic extract of Chandaeng showed the highest level of antioxidant activity. Furthermore, the potential of the extract to treat skin hyperpigmentation by inhibiting tyrosinase, an important melanin synthesis enzyme, was determined and the ethanolic extract was found to be an anti-tyrosinase agent. Finally, the crude ethanolic extract showed the highest total phenolic compound and flavonoid content. In conclusion, crude Chandaeng extract showed significant potential in activity against skin pathogenic bacteria, antioxidant activity, and tyrosinase inhibition. These properties of the extract could be applied to skincare cosmetics.

Effect of Extraction Period on Total Phenolics, Total Flavonoids, and Antioxidant Capacity of Ugandan Camellia sinensis (L) Kuntze, Black Primary Grades and Green Tea

Introduction. Globally, the consumption and production of tea are on the rise because of its beneficial constituents. Scarce literature exists on the effects of extraction periods on the contents of the biologically important and protective phytochemicals such as phenolics, flavonoids, and antioxidants in locally produced teas in Uganda. Aim. This study determined the effects of extraction periods on the aqueous total phenolic content (TPC) of local Camella sinensis, black primary grades and green tea, and their ecological differences, their total flavonoid content (TFC), and antioxidant capacities (AOC). Methods. Samples of local tea were collected from Kigezi, Ankole, and Buganda regions, and those of green tea were purchased from a local supermarket in Uganda. Four- and 40-minute infusions were separately prepared for each sample. Total phenolic and flavonoid contents were determined using the Folin–Ciocalteu and aluminium chloride methods using garlic acid and quercetin as standards, respectively. Antioxidant content was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and ferric reducing assay power (FRAP) methods, using ascorbic acid as the standard. Results. Green tea had the highest total phenolic content both with four-minute (9.50 ± 0.25 mgGAE/g) and 40-minute (25.81 ± 1.13 mgGAE/g) extractions, followed by D1 (4.14 ± 0.33 mgGAE/g) at four minutes and PF (23.60 ± 2.37 mgGAE/g) at 40 minutes. Regionally, Kigezi (4.71 ± 0.09 and 22.13 ± 0.85 mgGAE/g) at four and 40 minutes, respectively, gave the highest TPC. In TFC, tea from Buganda (4,371 ± 0.00 μgQE/g) was the highest. In DPPH and FRAP, GT (93.82 ± 0.03%, 39.04 ± 0.02 AAEμg/mL) was the best, followed by Buganda tea (88.71 ± 0.03%, 36.99 ± 0.01 AAEµg/mL), respectively. Conclusion. Longer extraction periods increase TPC in all teas. Green tea generates approximately twice the TPC generated by black tea in four-minute infusions. Green tea gives higher TPC, DPPH, and FRAP but less TFC than some black teas and is perhaps the best in terms of protection against oxidative damage to the body.

FTIR-Based Metabolomics for Characterization of Antioxidant Activity of Different Parts of Sesbania grandiflora Plant

Sesbania grandiflora, one of the flowering plants with great potential as a source of natural antioxidants because it contains chemicals such as tannin, phenolics, and flavonoids. However, there has been no extensive investigation on the antioxidant activity of isolated from different parts of this plant. This study aims to investigate the correlation between antioxidant activity and secondary metabolites extracted from three different parts (leaves, stem barks, and roots) of S. grandiflora plant using Fourier-transform infrared spectroscopy (FTIR) based metabolomics approach. The FTIR is a very useful technique for identifying the functional groups present in the mixtures, while antioxidant assay provides the base to select the part of the plant as the most potential source of antioxidant. The antioxidant properties were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and potassium ferricyanide reduction method. The multivariate data - analyses using Principal Component Analysis (PCA) and Partial Least Square (PLS) were conducted to compare the distribution of metabolites extracted from different parts of the S. grandiflora plant investigated. The PLS was performed to evaluate the relationship between the components of the extracts obtained from different parts of the plant and their antioxidant activities. The results exhibited that antioxidant activities of the extract of the stem barks, and roots are higher than that of the extract of the leaves. Also, the PLS model indicated that the functional group absorption data were significantly correlated with the IC50 values of antioxidant activity. Subsequently, based on the results of PLS ​​analysis displayed that C=C, C=O, and along with C-O functional groups are proposed as the main contributors to the antioxidant activity of the extracts tested. The extracts of different parts were grouped using PCA analysis with a total of principal components (PC) of 94%.

Phytochemical screening and antioxidative property evaluation of lipid-producing fungi

The increased demands for natural bioactive compounds have induced the search for unusual sources. Microorganisms, especially fungi are a potent source of secondary metabolites, which could act mainly as antioxidant compounds to prevent oxidative stress. In the present study three soil-isolated fungi Aspergillus niger, Aspergillus heteromorphus and Aspergillus fumigatus, were screened for their oleaginous property as well as their potential for the production of bioactive compounds. Fungal biomasses were freeze dried and extracted with methanol using a cold percolation process for the production of intracellular metabolites and the fungal culture media after fermentation were examined for extracellular metabolites. Intracellular and extracellular extracts of the isolated fungi along with the single-cell oils extracted from those fungi were screened for phytochemicals, which showed the presence of alkaloids, flavonoides, glycosides, phenols, saponins and terpenoids. All strains showed potent antioxidant activity, determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and ferric reducing antioxidant power (FRAP) activity. Extracellular extract and single-cell oil of A. heteromorphus showed the highest antioxidant activity with maximum ABTS radical scavenging activity and reducing potential. Highest content of phenolic and flavonoid compounds within the isolated fungi was found to be 37.58mg gallic acid equivalent (GAE)/g and 62.07mg catechine equivalent (CE)/g, respectively. Chromatographic analysis of the intracellular and extracellular extracts of the fungi showed the presence of gallic acid, di-hydroxy benzoic acid, ferulic acid, quercetin, epigerin, kampferol, trans cinnamic acid, chlorogenic acid and rutin, which made them biologically important and beneficial for human health.

Chemical Components of Volatile Oil Extracted from the Fermentation Broth of Ganoderma lingzhi (Agaricomycetes) Coupled with Its Antitumor and Antioxidant Activities In Vitro

Volatile oil extracted from fermentation broth of Ganoderma lingzhi by hydrodistillation was analyzed based on gas chromatography-mass spectrometry (GC-MS). Its antitumor activity was tested on K562, SW620, A549, HepG2 cells in vitro. In addition, the antioxidant activity of the oil was determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. In total, 16 constituents were identified accounting for about 99.99% of the total volatile oil in the fermentation broth of G. lingzhi. Among these components, 1-propanol (33.33%), phenylacetaldehyde (24.24%), 2-hexyl-1-decanol (12.12%) were found to be the major constituents. The antitumor results showed that the IC50 of the inhibition to the proliferation of K562, SW620, A549, HepG2 cells were 32.2, 78.9, 96.4, 99.0 μg/mL, respectively. And the oil could inhibit the proliferation of K562 cells by apoptosis induction and cell cycle arrest at S phase. Moreover, the oil exhibited radical scavenging activity (IC50 = 0.1469 mg/mL) in DPPH assay.

Isolation of Cherry Seed Oil Using Conventional Techniques and Supercritical Fluid Extraction.

This study aims to compare the suitability of three extraction techniques (cold pressing, Soxhlet and supercritical fluid extraction (SFE)) to isolate oil from cherry seeds. Oils were examined in terms of extraction yield, fatty acids profile, tocopherols yield and antioxidant activity. Additionally, influence of SFE parameters was evaluated using one-factor-at-a-time design with pressure (200-350 bar), temperature (40-70 °C), flow rate (0.2-0.4 kg/h) and particle size (<800 µm and >800 µm). Oil yields ranged from 2.50% to 13.02%, whereas the highest yield was achieved with SFE. Samples were rich in polyunsaturated fatty acids, regardless of the applied extraction technique. The main fatty acids were linoleic (46.32-47.29%), oleic (40.89-41.65%), palmitic (6.56-8.00%) and stearic (2.21-2.30%) acid. Total tocopherols yield was between 16.63 mg/100 g oil and 60.61 mg/100 g oil, and highest yield was achieved with SFE. Among the tocopherols, γ-tocopherol was the most abundant, followed by α-, δ- and β-tocopherol. Antioxidant activity was determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic) cation (ABTS) assays, and the results indicated that SFE extracts exhibited better or comparable antioxidant potential compared to traditional techniques. The comparison between modern and conventional extractions for oil recovery demonstrates pros and cons for the possibility of industrial application.