Free Radical Scavenging Method Research Articles

Antioxidant activity of Loranthus ferrugineus twigs extracts

Background: A coffee parasite, Loranthus ferrugineus, is a type of parasitic plant that is widely used as a medicinal plant. It has many activities, including as an antioxidant agent. Objective: This study is to determine the antioxidant activity in the twig extracts of L. ferrugineus. Method: The twigs of L. ferrugineus were collected from Pekanbaru, Riau Province, Indonesia. Extraction was carried out by maceration of the dry twigs using methanol, and then liquid-liquid extraction was carried out to obtain ethyl acetate and methanol fractions. The antioxidant activity test was carried out using the radical DPPH and NO free radical scavenging methods by calculating the IC50 values, and the total phenolic content (TPC) was measured. Result: The antioxidant activity assay of the DPPH method on ethyl acetate and methanol extracts revealed IC50 values of 20.85 µg/mL and 18.83 µg/mL, respectively. Meanwhile, the NO free radical method on ethyl acetate and methanol extracts showed IC50 values of 78.52 µg/mL and greater than 1000 µg/mL. The total phenolic content of the ethyl acetate extract was 26.78 mgGAE/gram, while it was 24.85 mgGAE/gram in the methanol extract. Conclusion: The ethyl acetate and methanol extracts could inhibit free radicals from DPPH, which was classified as very strong antioxidant sources. Meanwhile, the inhibition of the extracts against the NO free radical was very weak.

Phytochemical Screening and Antioxidant Activities of Some Seaweed from Kabung Island Waters West Kalimantan

Seaweed is one of the prima donna marine biota which is widely used as a natural antioxidant. Various species of seaweed are found growing naturally in the waters of Kabung Island, West Kalimantan. This study aims to determine the phytochemical content and antioxidant activity of each genus Turbinaria, Hypnea and Caulerpa from those collected in the waters of Kabung Island. Seaweed extraction uses maceration method with methanol to remove active compounds. Next, a phytochemical screening was performed using specific reagents such as alkaloids, steroids, flavonoids, tannins and saponins which will change color or form precipitates. The free radical scavenging method of 2,2-diphenyl-1-picrylhydrazyl (DPPH) solution was used to test the antioxidant activity of each seaweed extract. The active compound in the sample extract will be formed if there is a change in the color of free radicals from dark purple to light yellow or clean. The results showed that the phytochemical screening of the three seaweed extracts contained tannins, flavonoids and saponins. Meanwhile, positive alkaloids were found in Turbinaria and Caulerpa extracts, and steroids were indicated by the genus Hypnea and Caulerpa. Antioxidant screening showed that Caulerpa extract was categorized as a potent antioxidant with an IC50 value of 88.57 ppm, higher than the IC50 of Turbinaria and Hypnea extracts, which were 114.32 and 138.42 ppm respectively and classified as weak antioxidants.

Serum Free Radical Scavenging Capacity Profiles of Patients with Chronic Obstructive Pulmonary Disease.

Oxidative stress is an important mechanism for the development and progression of chronic obstructive pulmonary disease (COPD). It may also contribute to systemic manifestation in patients with COPD. Reactive oxygen species (ROS) including free radicals play a crucial role in oxidative stress in COPD. The aims of this study were to determine serum scavenging capacity profile against multiple free radicals and to evaluate its correlation with pathophysiology, exacerbations, and prognosis in patients with COPD. Serum scavenging capacity profile against multiple free radicals comprising hydroxyl radical (•OH), superoxide radical (O2 -•), alkoxy radical (RO•), methyl radical (•CH3), alkylperoxyl radical (ROO•), and singlet oxygen (1O2) was assessed using the multiple free-radical scavenging method in 37 patients with COPD (mean age, 71 years; mean forced expiratory volume in 1 s, 55.2% predicted). The severity of emphysema was evaluated by Goddard classification on chest computed tomography. Exacerbations were recorded prospectively for 1 year and the overall mortality was assessed 5 years after the initial assessment. •OH scavenging capacity was significantly decreased (p < 0.05) and O2 -• and •CH3 scavenging capacity tended to decrease in patients with COPD compared to that in healthy controls. On the other hand, ROO• scavenging capacity tended to increase. In addition, RO• scavenging capacity was associated with severity of emphysema (p < 0.05) and exacerbation frequency (p < 0.02). There was a difference in the profile of the scavenging capacity between survived and deceased patients with COPD for 5 years after initial assessment. Characteristic profile of free radical scavenging capacity can provide insight into the pathophysiology and prognosis of patients with COPD.

In-vitro Antioxidant and Antitumor Activity of Dihydropyrimidine-2(1-H)-thione Derivatives with Carbazole Moiety

Aim: Prepared a series of molecules called Dihydropyrimidine-2(1-H)-thione of carbazole to evaluate antioxidant and antitumor activity. Materials and Methods: Compounds from DTP-1 to DTP-11 were prepared and subjected for Spectral analysis like infrared, 1H NMR, and Mass spectroscopy. Further evaluated antioxidant property of molecules using DPPH free radical scavenging method and analyzed the antitumor activity by MTT assay. Results: The molecule DTP-4 (4-(9H-carbazol-9-yl)-6-(3-hydroxyphenyl)-5,6-dihydropyrimidine-2(1H)-thione) exhibit the spectral values i.e, Mass, m/z: 371.08, 166.45; IR (KBr) νmax, cm−1: 3420 (NH Str), 3567(O-H); 1H NMR (MHz, δ): (15H, Ar-H) 8.003-7.019, (1H, N-H) 11.129, (1H, O-H) 10.03 and DTP-6: 4-(9H-carbazol-9-yl)-6-(4-Dimethylamino-phenyl)-5,6-dihydropyrimidine-2(1H)-thione Mass value of m/z: 398.03, 166.09; IR (KBr)vmax, cm−1: 3419 (NH Str), (Ar C=S); 1H NMR (MHz, δ): (15H, Ar-H) 8.128-7.121, (1H, N-H) 11.290, (6H, -N-(CH3)2)3.491-2.791. Conclusion: Among all of those prepared molecules, DTP-4, which includes the functional group (3-OH) ortho-hydroxy, has an IC50 value of 2.32 μm against the Jurkat T cell line while compound DTP-06, which contains the functional group 4-dimethylamino, exhibits an IC50 value of 05.39 μm against the HeLa cell line.

Evaluation of mineral content and antioxidant activity of Detarium senegalense leaves extracts

This study aimed to evaluate mineral composition and antioxidant activity of Detarium senegalense leaves extracts. Toxic and edible chemotypes of the plant were used. Two free radical scavenging methods using 2,2-diphenyl-1-picryl hydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) were employed to evaluate antioxidant activity. Mineral element contents were determined by X-ray fluorescence spectrometry. Ethanolic macerations of leaves were performed and dry extracts obtained, solubilized in water, were fractionated successively using dichloromethane and ethyl acetate. An antioxidant activity was attributed to extracts concentrations between 0.625 and 500 μg/mL. Mean inhibitory concentrations (IC50) ranged from 16.263±0.481 μg/mL to 260.942±36.293 μg/mL for DPPH and 2.707±0.064 μg/mL to 38.238±0.815 μg/mL with ABTS. Analysis of mineral composition revealed presence of various elements such as calcium, phosphorus, potassium, sulfur, chlorine, iron, manganese, copper, zinc and strontium at concentrations ranging from 0.028±0.001 to 24.351±0.157 mg/g. Results showed that Detarium senegalense edible chemotype leaves presented the most important antioxidant activities (ABTS and DPPH). For macroelements, phosphorus, potassium and sulfur were found to be greater in edible chemotype leaves (1.841 ± 0.107, 20.443 ± 0.193 and 4.495 ± 0.089 mg/g) compared to those of toxic chemotype (1.667 ± 0.115, 14.799 ± 0.177 and 3.522 ± 0.089 mg/g respectively). Several microelements (manganese, copper, zinc and strontium) had slightly higher concentrations in toxic chemotype leaves. Therefore, leaves extracts from toxic and edible chemotypes of Detarium senegalense present interesting antioxidant properties. These leaves also constitute a good source of minerals, whose main elements are potassium, calcium, sulfur and phosphorus. The present work reveals that these leaves could be introduced in food formulations and manufacture of inexpensive phytomedicines, notably for low income populations.

Fluorescence and antioxidant activity of heterologous expression of phycocyanin and allophycocyanin from Arthrospira platensis.

Phycocyanin and allophycocyanin are important active substances in Arthrospira platensis, because of their fluorescent characteristic and antioxidant capacity. In order to solve the problem of insufficient production and inconvenient modification of natural protein, recombinant expression was performed and the fluorescence activity and antioxidant activity was analyzed to meet the demand for phycocyanin and allophycocyanin. A total of seven recombinant strains were constructed in this study, including individual phycocyanin or allophycocyanin, co-expression of phycocyanin-allophycocyanin, and their co-expression with chromophore, and the expression strain for individual chromophore. Different molecular weights of phycocyanin and allophycocyanin were detected in the recombinant strains, which indicated the different polymers expressed. Through mass spectrometry identification, phycocyanin and allophycocyanin may form a dimer of 66 kDa and a polymer of 300 kDa. The results of fluorescence detection showed that phycocyanin and allophycocyanin combined with phycocyanobilin to show fluorescence activity. The fluorescence peak of recombinant phycocyanin was mainly concentrated at 640 nm, which was similar to natural phycocyanin, the fluorescence peak of purified recombinant allophycocyanin was at about 642 nm. The fluorescence peak of the co-expressed recombinant phycocyanin-allophycocyanin is located at 640 nm, and the fluorescence intensity is between the recombinant phycocyanin and the recombinant allophycocyanin. After purification, the fluorescence peak of the recombinant phycocyanin is more concentrated and the fluorescence intensity is higher, which is about 1.3 times of recombinant phycocyanin-allophycocyanin, 2.8 times of recombinant allophycocyanin, indicating that phycocyanin may be more suitable to be used as fluorescence probe in medicine. The antioxidant capacity was measured by using total antioxidant capacity (T-AOC) and DPPH (2,2'-diphenyl-1-triphenylhydrazino) free radical scavenging method, and the recombinant phycobiliprotein showed antioxidant activity. Phycocyanobilin also has certain antioxidant activity and could enhance the antioxidant activity of phycobiliprotein to a certain extent. Recombinant phycocyanin-allophycocyanin polymer has stronger T-AOC, which is about 1.17-2.25 times that of the other five recombinant proteins. And recombinant phycocyanin has stronger DPPH antioxidant activity, which is about 1.2-2.5 times that of the other five recombinant proteins. This study laid the foundation for the application of recombinant phycocyanin and allophycocyanin in medical detection and drug development.

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.

Phytochemical, Antioxidant and Antibacterial Evaluations of Ipomoea batatas L. from Riau, Sumatera Island, Indonesia

Indonesia is rich in its biodiversity of medicinal plants used traditionally for healing several ailments. Ipomoea batatas L., one of the traditional herbs of Indonesia that is popularly known as sweet potato, has played a significant role as a source of energy and phytochemicals in human nutrition and animal feeding. In traditional use, Ipomoea batatas (I. batatas) is effectively utilized in herbal medicine as an anti-inflammatory agent for treatment of illnesses and infectious oral diseases. This study aimed to evaluate the phytochemical screening, with the antibacterial and antioxidant activity of extracts of I. batatas leaves. Antibacterial effect was tested against Grampositive bacteria, Gram-negative bacteria and resistant bacteria through the agar disc diffusion method while antioxidant activity was analyzed using the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging method. The phytochemical screening showed the ethanol extract contains alkaloids, triterpenoids, flavonoids, tannins and saponins. The IC50 value for antioxidant properties was 233.476±0.01 ppm. Antimicrobial activity showed that percentage of inhibition growth was 83.61%. Ethanol extract showed the moderate antibacterial activity against Gram-positive bacteria, Staphylococcus aureus and Streptococcus mutans with diameter inhibition zone 8.7±0.01 cm and 10.2±0.3 cm in concentration 40%, respectively. Owing to the presence of its rich variety of secondary metabolites, the leaves extract of Ipomoea batatas L. is expected to exhibit more medicinal properties and be useful to develop as therapeutic agents in the future.

Formulation and development of Oral herbal liquid dosage form with its quality evaluation parameters

The present work deals with the formulation and development of oral herbal liquid dosage and its comparative study with marketed dosage for quality evaluation parameters. We have used different Poly-herbs for the formulation of syrup because they expressed high effectiveness in a vast number of diseases. As aforementioned the therapeutic effect of herbal medicines is exerted due to the presence of different constituents and the effects are further potentiated when compatible herbals are formulated together in PHFs (Poly-herbal formulations). PHF show compatible effect with those of standard allopathic drugs. We had tested its Quality control pre and post-formulation evaluation parameters. The Quality control tests for developed herbal syrup include: Physical appearance (Color, Odor, and Taste), Clarity tests, solubility tests, pH, Density, Viscosity, Specific gravity, Refractive index, FTIR study of active constituent used in herbal syrup. This syrup is also tested for acute oral toxicity study (LD50), Antioxidant activity by using Nitric oxide free radical scavenging method, and hepato-protective activity by using paracetamol-induced hepatotoxicity in rats. From the obtained results, we concluded that formulated poly-herbal syrup passed all quality control tests and also proved its effectiveness. The formulation F2 and F3 were the best poly-herbal formulation and it was selected for further study. In hepato-protective activity, F2 formulation when compared with the standard formulation of silymarin have shown good results.

“ESTIMATION OF RADICAL SCAVENGING POTENTIAL OF SELECTED MEDICINAL PLANTS OF LAHORE, PAKISTAN”

&#x0D; &#x0D; &#x0D; In the current research, in vitro antiradical potential of some medicinal trees of Lahore, Pakistan was investigated. Various fruits and pods of 25 medicinal plants (Prosopis juliflora, Carissa carandas, Ceiba speciosa, Heterophragma adenophyllum Cestrum diurnum Jacaranda mimosifolia, Diospyros malabarica, Terminalia bellerica, Ficus lyrata, Diospyros peregrine, Cinnamomum verum, Erysimum cheiri, Buchanania lanzan, Withania somnifera, Fagonia arabica, Berberis lycium, Strychnos potatorum, Matthiola incana, Ziziphora tenuior, Centaurea behen, Rosa indica, Punica granatum, Lodoicea maldivica, Cassia absus, Celastrus paniculatus) were extracted by ethanol. Different concentrations of fruit extracts (1, 0.5, 0.25, 0.125 mg/mL) were prepared to evaluate in vitro antioxidant activity. The DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging method was performed and compared with standards like Vitamin E, BHT (Butylated hydroxytoluene) and ascorbic acid. Many plant extracts exhibited 80% of DPPH radical scavenging activity. F. Arabica, S. potatorum, M. incana, P. granatum, C. behen, W. somnifera, T. bellerica, and H. adenophyllum showed significant anti-radical potential (98.4±0.52, 96.40±0.52, 96.42±0.51, 94.58±0.52, 94.47±0.50, 94.65±0.56, 94.55±0.50, 91.42±0.51% inhibition, respectively) at 1 mg/mL equivalent to standards i.e. Vitamin E, BHT and ascorbic acid inhibition (88.25±0.2, 78.1±0.3 and 40.51±0.17%), respectively. Moreover, the dose dependent activity was observed as decline in the percentage inhibition at lower extracts concentration. The 50% inhibitory concentration (IC50) was also determined for the extracts that varied from 0.014± 0.001 (W. somnifera and J. mimosifolia) to 2.69±0.001 (B.lanzan) mg/mL depending on the sample extracts. The natural antioxidants in plants may be used in foods and natural products as a substitute to synthetic antioxidants, which have side effects.&#x0D; &#x0D; &#x0D;

Physiochemical and nutritional evaluation of whole kumquat fruits powder and its protective effect on thyroid hormones and blood sugar levels in diabetic rats.

The present study was conducted to evaluate the chemical composition, antioxidant activity and hypoglycemic effects of whole kumquat (Ku) powder in diabetic rats fed a high-fat-high-cholesterol (HFHC) diet. The antioxidant activities were evaluated using stable 1,1-diphenyl 2-picrylhydrazyl (DPPH) free radical scavenging method, 2,2´-azinobis (3-ethyl benzo thiazoline-6-sulphonic acid) radical cation (ABTS) and Ferric reducing antioxidant power (FRAP). Total phenolic content was (51.85 mg GAE/g) and total flavonoid content was (0.24 mg Cateachin Equivalent, CE/g). DPPH and ABTS values were 3.32 and 3.98 mg Trolox equivalent (TE)/g where FRAP value was 3.00 mM Fe2+/kg dry material. A total of 90 albino rats were used in the present study. Rats group were as follows: normal diet; normal treated (2, 4, and 6% Ku.), diabetic rats (non-treated), diabetic + HFHC diet (non-treated), HFHC (non-treated), Diabetic (treated), HFHC (treated) and Diabetic + HFHC (treated). The diets were followed for 8 weeks. Blood samples were collected at the end of the experiment. Serum glucose was recorded and thyroid hormones (T4, Thyroxine and T3, Triiodothyronine) were conducted. Diet supplemented with Kumquat at different concentrations have a hypoglycemic effect and improve the thyroid hormones of both diabetic rats and HFHC diabetic rats.

Evaluation of Phytochemicals, Anti-inflammatory and Antioxidant Potential of Aegle marmelos L. Leaves

Aegle marmelos is a deciduous tree with trifoliate leave commonly found in the Indian subcontinent. The present study is to diagnose the phytochemicals physiochemical, qualitative and quantitative estimation. Total phenolic content was recorded at 53.52±3.25 µg Gallic acid equivalent (GAE) /mg of plant extract, total tannin content was observed at 6.4±1.02 μg GAE/mg and total flavonoid content was recorded at 37.4±2.65 μg Quercetin equivalent/mg. The study also comprised the Anti-inflammatory and anti-oxidant activity of plant leaves. Anti-inflammatory activity was examined through the HRBC method and compared with the standard drug diclofenac sodium. Ethanolic extract of leaves shows significant anti-inflammatory activity and provides 61.04±2.89 % of protection against hemolysis at 2000µg/ml of leave extract whereas at the same concentration diclofenac sodium provides only 54.55±2.35 % protection against hemolysis. The antioxidant potential of plant extract examines through DPPH free radical scavenging method. Leave extract showed better antioxidant activity in comparison to ascorbic acid. IC₅₀ of plant extract is 48.99 ±1.96 % which is also better than the value of IC₅₀ of ascorbic acid which was recorded at 50.39±2.05. The study showed that leaves extract of the plant has significant potential for the treatment of oxidative stress and inflammation.

Effect of Freeze-Drying of Prickly Pear (Opuntia Ficus-Indica) on Flavonoids and Antioxidants

Prickly pear fruits (PPF) play a high-quality role in health due to its rich content of antioxidant and phenolic materials. This research is a cross sectional descriptive study, the efficacy of the drying method on the chemical attributes of PPF pulp on quality and safety during the storage period. The sample was divided into control and treatment by drying (oven-drying (OD) and freeze-drying (FD)). The flavonoid concentration in the pulp methanolic extracts was measured using spectrophotometry; the diphenylpicrylhydrazyl (DPPH) capacity was assessed using an adapted DPPH free radical-scavenging method, values of total phenolic content (TPC) and total flavonoid content (TFC) of fresh and dried PPF. The drying method had a significant effect on TFC; values were 39.88 and 18.05 μg/g CE fresh weight (FW) for the OD and FD, respectively. The FD exhibited about 77.56 ± 8.4 for TPC whereas the TFC estimated to 26.8 ± 11.4 mg GAE/100 gm FW. The DPPH for FD samples was significantly higher (249.8 ± 20.6) than that of the OD (75.2 ± 7.2). Mean values of Cupric Ion Antioxidant Reducing Capacity (CUPRAC) were 1005, 973 and 553 µM TE for fresh, FD and OD samples respectively. Meanwhile, the values were in significant differences in comparison between FD and OD of 973.5 ± 87.1 and 553.15 ± 16.6, respectively. The chemical composition, antioxidant capacity (DPPH, FARAP &amp; CUPRAC) of PPF, and TFC of fruits were changed by drying. FD had the best results for the antioxidant capacity values as were the closest to the values of the fresh sample. Therefore, FD for PPF storage is proven to be recommended. Keywords: freeze-drying, prickly pear, Opuntia ficus-indica, antioxidants. https://doi.org/10.55463/issn.1674-2974.50.2.22

Ocimum gratissimum L.: A natural alternative against fungi associated with bean and maize seeds during storage

The aim of the study was to evaluate in vitro antioxidant and antifungal activities of the ethanolic extract and its fractions from Ocimum gratissimum leaves. The ethanolic extract was obtained by maceration in ethanol and subsequent fractionation with solvents of increasing polarity (hexane, dichloromethane, ethyl acetate and butanol). The Minimum Inhibitory Concentration (MIC) was determined for the ethanol extract and dichloromethane fraction. The antioxidant capacity was evaluated by DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) free radical scavenging methods, and by FRAP (Ferric Reducing Antioxidant Power). The in vitro antifungal effect was determined by the agar diffusion method on Aspergillus sp. and Rhizopus sp. fungi associated with corn and bean seeds during storage. The best samples with antifungal effect were determined by gas chromatography-mass spectrometry (GC/MS). The ethanolic extract had strong antioxidant capacity for all tested methods (DPPH 371.10±2.98 μg ml-1, ABTS 182.43±1.10 μg ml-1, FRAP 262.39±3.61 TEAC). Regarding the antifungal activity, the ethanolic extract and dichloromethane fraction resulted in total suppression (100%) of fungal growth and MIC ranged from 0.625 to 1.25 mg ml-1. In the GC/MS analysis, 22 substances were detected in all samples evaluated, with predominance of eugenol. These results indicated high biological potential of this plant as a biofungicide

Evaluation of the antioxidant and antibacterial activity of aqueous and ethanoic extracts of two medicinal plants used to treat diarrhea in Côte d’Ivoire

This study was initiated to evaluate the antioxidant and antibacterial activities of aqueous and ethanoic extracts of Anthocleista djalonensis and Uvaria chamae, two plants of the African pharmacopoeia used by the peoples of the northern Côte d’Ivoire to treat severe cases of diarrhea. A series of extraction by maceration was carried out. The extracts obtained were assayed by the colorimetric method and their antioxidant activity determined by spectrophotometer using the free radical scavenging (DPPH) and iron reduction (FRAP) methods. Dilution and agar diffusion methods on Mueller Hinton medium were used to determine MICs and inhibition diameters. The assay of the extracts determined the polyphenol content ranging from 6.8 to 21.1 mg. The total phenol content of the ethanol extract of Uvaria chamae was the highest. Evaluation of the free radical scavenging activity and the reducing power of ferric ions to ferrous ions of the extracts of both plants indicated variable IC50 values ranging from 4 to 14 (μg/mL). The lowest value (4 μg/mL) close to that of vitamin C (reference molecule) (3.5 μg/mL) was obtained with the aqueous and ethanoic extracts of Anthocleista djalomensis and Uvaria chamae respectively. Furthermore, all germs were found to be sensitive to the action of the extracts with inhibition diameters greater than 10 mm and MICs greater than 3.12 mg/mL. This sensitivity could be due to the presence of phytochemicals such as total phenols, flavonoids, tannins, alkaloids, saponins whose antimicrobial activities have already been shown. These investigations justify the traditional use of these plants in the treatment of diarrhea and dysentery.

Kidney bean (Phaseolus vulgaris L.) milk substitute as a novel plant-based drink: Fatty acid profile, antioxidant activity, in-vitro phenolic bio-accessibility and sensory characteristics

Recently, plant-based milk alternatives have gained popularity due to healthy food trends, sustainability concerns, and environmental repercussions. The current study is unique for the investigation of in vitro phenolic bioaccessibility, fatty acid composition, and sensory evaluation of plant-based milk from two different local kidney bean varieties grown in Turkey, oval and cherry. Kidney bean milk had 1.92–2.32% protein, which was slightly greater than other commercial plant-based milk alternatives. The majority of the fatty acids in the samples were α-linolenic acid (25.66–27.78%) and palmitic acid (18.95–23.08%). The total antioxidant capacity bio-accessibility of kidney bean milk was 154%–295% by cupric reducing antioxidant capacity (CUPRAC) and 50%–186% by α, α-diphenyl-β-picrylhydrazyl (DPPH) free radical scavenging method while the total phenolic content bio-accessibility varied between 207%–266%. Overall acceptance of kidney bean milks varied between 2.9 and 4.1 out of 10. These findings presented that kidney bean milk is an alternative for the food industry with its rich bio-accessible antioxidant capacity and fatty acid profile although intense beany flavor detected during sensory analysis.

ANTIOXIDANT ACTIVITY AND PHENOLIC PROFILE OF FRUITS FROM SOME ROMANIAN SHRUB FRUIT VARIETIES

The berries are rich in polyphenols, vitamins, and other bioactive compounds, and exhibit antioxidant, antimicrobial, anti-inflammatory and anticancer activities. In this work, antioxidant activity (AA) and a phenolic profile of berries fruits belonging to the Aronia melanocarpa (Michx.) Elliott, ʹMelromʹ cv., Lonicera caerulea var. kamtschatica, ʹKamiʹ cv., and Sambucus nigra L., ʹElromʹ cv. were studied. All three cvs. were previously patented by the Research Institute for Fruit Growing Pitesti, Romania. Alcoholic extracts from berries were obtained by four methods: continuous, maceration, ultrasounds and microwaves-assisted. The antioxidant content of extracts was evaluated by an HPLC method. AA was determined by DPPH free radical scavenging method. Total phenol, flavonoid, and anthocyanin contents were determined by spectrophotometric methods. The AA values were reported as equivalents (µg mL-1 extract) caffeic and gallic acids, morin, quercetin, rutin, and are in concordance with the results of the chromatographic method. In addition, the chromatographic method allowed identifying the p-coumaric acid, caffeic acid, chlorogenic acid, rutin, and epicatechin. The experimental results have shown that analyzed fruit extracts have high antioxidant activity, due mainly to flavonoids and anthocyanins in high concentration. Therefore, extracts from mentioned berries can be used in different nutraceutical products with high antioxidant potential.

Evaluation of non-timber forest products used as medicinal plants from East Kalimantan (Indonesia) to inhibit ?-glucosidase and free radicals

Abstract. Ramadhan R, Tosepu R, Phuwapraisirisan P, Amirta R, Phontree K, Firdaus YFH, Abdulgani N, Muttaqin MZ, Saparwardi. 2022. Evaluation of non-timber forest products used as medicinal plants from East Kalimantan (Indonesia) to inhibit ?-glucosidase and free radicals. Biodiversitas 23: 5551-5558. Non-timber forest products (NTFPs) have essential uses as medicines, food sources, and traditional ceremonies for the local people living in forest areas. Medicinal plants are one of the non-timber forest products used as traditional medicine by local people in East Kalimantan. This study was conducted to search for new natural antidiabetic and antioxidant resources from medicinal plants used traditionally in Mahakam Ulu District, East Kalimantan, based on ethnopharmacological information. The present study evaluates non-timber forest products as in vitro antidiabetic (rat intestinal ?-glucosidase inhibitory activity) and antioxidant (free radical scavenging activity against DPPH, ABTS, and Nitric Oxide) activities. The antidiabetic and antioxidant activities were evaluated using ?-glucosidase inhibition assay and free radical scavenging methods. This study demonstrated that methanol extracts of Flacourtia rukam Zoll. &amp; Moritzi, Syzygium chloranthum (Duthie) Merr. &amp; L.M. Perry and Shorea balangeran Burck exhibited strong ?-glucosidase inhibitory activity with maltose as a substrate with IC50 values of 0.034 mg/mL, 0.039 mg/mL, and 0.039 mg/mL, respectively. On the other hand, methanol extract of S. chloranthum displayed the strongest ?-glucosidase inhibitory activity in sucrose as a substrate, similar to the IC50 value of the quercetin as a positive control. Furthermore, the antioxidant test showed that all medicinal plant extracts from East Kalimantan are good sources of natural antioxidants indicated by their IC50 values. The results of this study support the scientific background of the uses of medicinal plant extracts from East Kalimantan as folk medicine.

Gallic acid a flavonoid isolated from Euphorbia hirta antagonizes gamma radiation induced radiotoxicity in lymphocytes in vitro.

The current study was executed to isolate and evaluate gallic acid from Euphorbia hirta for in vitro radioprotective potentials against gamma irradiation caused radiotoxicity in human lymphocytes. The defatted E.hirta plant material was treated to methanol extraction using the soxhlet device. Bioflavonoids were isolated from the E.hirta methanol extract using column chromatography. In human cells exhibited to gamma radiation, separated flavonoid gallic acid was examined for in vitro radioprotective potentials using the micronucleus test, DNA fragmentation assay, superoxide free radical scavenging method, and apoptic assay. The frequency of micronuclei was considerably declined when cells were preprocessed with gallic acid (25g/mL) before being exhibited to 2Gy gamma radiation, as determined by the cytokinesis blocked micronucleus test. Similarly, pre-gamma radiation treatment of human cells with gallic acid led in markedly less DNA injury, as assessed by comet metrics like olive tail moment and percent tail DNA. Gallic acid (25g/mL) given to lymphocytes prior to gamma irradiation considerably decreased the percentage of apoptotic bodies. Gallic acid also considerably lowered the reactive oxygen species concentrations elicited by gamma radiation. Our findings showed that gallic acid protects lymphocytes isolated from human blood from gamma radiation-induced DNA destruction and anti-apoptotic activity, which could be because of inhibition of free radicals formed by gamma radiation as well as the decline of gamma radiation-induced oxidative stress.

Physical Chemical Characterization, Determination of Antioxidant Activity and Phytochemical Screening of Gambir Claw Herbal Tea (Uncaria gambir)

Uncaria gambir is a member of Rubiaceae family. Information related to antioxidants and the use of this plant in the food and cosmetic industry has been widely reported. This study aims to determine the physicochemical properties, phytochemical content and antioxidant activity of herbal tea made from gambir claw, which was collected from the Pontianak City area of ​​West Kalimantan. Determination of physicochemical properties is based on measuring the parameters of pH, water content, ash content and organoleptic including taste, odor and color when dissolved in water. Phytochemical screening was carried out using specific reagents to determine the presence of flavonoid compounds, tannins, alkaloids and saponins. Antioxidant activity was determined using the free radical scavenging method 2,2-diphenyl-1-picrylhydrazyl (DPPH). From the results of the measurement of the physical and chemical properties of gambir claw herbal tea, the pH, ash content, moisture content and powder conditions met the requirements of SNI No 3836 of 2013, phytochemical screening showed positive results for flavonoid and tannin compounds, and antioxidant activity was obtained at 88,398 ppm, classified as a strong antioxidant.