The aim of this study was to develop and validate a rapid and simple high performance thin layer chromatographic (HPTLC) method to screen for antioxidant activity in algal samples. 16 algal species were collected from local Victorian beaches. Fucoxanthin, one of the most abundant marine carotenoids was quantified directly from the HPTLC plates before derivatization, while derivatization either with 2,2-diphenyl-1-picrylhydrazyl (DPPH) or ferric chloride (FeCl3) was used to analyze antioxidants in marine algae, based on their ability to scavenge non biological stable free radical (DPPH) or to chelate iron ions. Principal component analysis of obtained HPTLC fingerprints has classified algae species into 5 groups according to their chemical/antioxidant profiles. The investigated brown algae samples were found to be rich in non-and moderate-polar compounds and phenolic compounds with antioxidant activity. Most of the phenolic iron chelators also have shown free radical scavenging activity. Strong positive and significant correlations between total phenolic content and DPPH radical scavenging activity showed that, phenolic compounds, including flavonoids are the main contributors of antioxidant activity in these species. The results suggest that certain brown algae possess significantly higher antioxidant potential when compared to red or green algae and could be considered for future applications in medicine, dietary supplements, cosmetics or food industries. Cystophora monilifera extract was found to have the highest antioxidant concentration, followed by Zonaria angustata, Cystophora pectinate, Codium fragile, and Cystophora pectinata. Fucoxanthin was found mainly in the brown algae species. The proposed methods provide an edge in terms of screening for antioxidants and quantification of antioxidant constituents in complex mixtures. The current application also demonstrates flexibility and versatility of a standard HPTLC system in the drug discovery. Proposed methods could be used for the bioassay-guided isolation of unknown natural antioxidants and subsequent identification if combined with spectroscopic identification.
In current work, the nutritional composition, bioactive compounds, total phenolic contents and anti-oxidant activity of young Malaysian ginger rhizome were investigated. Proximate analysis and high performance liquid chromatography (HPLC) recruited to determine nutritional composition and bioactive compounds. The total flavonoid (TF) and total phenolic contents (TPC) of ginger rhizome were determined by aluminium chloride calorimetric assay and Folin-Ciocalteau reagent, respectively. 2,2’-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method were used to measure antioxidant capacity. The rhizome contained high moisture content and low level of carbohydrate and energy. 6-gingerol was the most abundant component in the selected ginger, and total flavonoid and phenolic content were reported to be 3.66±0.45 mg gallic acid/g and 10.22±0.87 mg quercetin/g of dry weight of rhizome, respectively. The rhizome also showed lower antioxidant activity than controls, with the IC 50 value of 46.5 vs. 15.5 for α-tocopherol and 22 for BHT. The results of this study predicted that the young ginger rhizome originated from Malaysia may exhibit anti-oxidative and anti-inflammatory potentials due to high levels of gingerols, total flavonoid and phenolic compounds and antioxidant capacity.
Recently much attention has been paid to biologically active plants because of their low production cost and fewer adverse effects compared with chemical drugs. In the present investigation the bioactivity of Phyllanthus niruri ethanol and aqueous extracts was evaluated in vitro.
Defatted Jatropha curcas L. (J. curcas) seed kernels contained a high percentage of crude protein (61.8%) and relatively little acid detergent fiber (4.8%) and neutral detergent fiber (9.7%). Spectrophotometric analysis of the methanolic extract showed the presence of phenolics, flavonoids and saponins with values of 3.9, 0.4 and 19.0 mg/g DM, respectively. High performance liquid chromatography (HPLC) analyses showed the presence of gallic acid and pyrogallol (phenolics), rutin and myricetin (flavonoids) and daidzein (isoflavonoid). The amount of phorbol esters in the methanolic extract estimated by HPLC was 3.0 ± 0.1 mg/g DM. Other metabolites detected by GC-MS include: 2-(hydroxymethyl)-2 nitro-1,3-propanediol, β-sitosterol, 2-furancarboxaldehyde, 5-(hydroxymethy) and acetic acid in the methanolic extract; 2-furancarboxaldehyde, 5-(hydroxymethy), acetic acid and furfural (2-furancarboxaldehyde) in the hot water extract. Methanolic and hot water extracts of kernel meal showed antimicrobial activity against both Gram positive and Gram negative pathogenic bacteria (inhibition range: 0-1.63 cm) at the concentrations of 1 and 1.5 mg/disc. Methanolic extract exhibited antioxidant activities that are higher than hot water extract and comparable to β-carotene. The extracts tended to scavenge the free radicals in the reduction of ferric ion (Fe(3+)) to ferrous ion (Fe(2+)). Cytotoxicity assay results indicated the potential of methanolic extract as a source of anticancer therapeutic agents toward breast cancer cells.
Plants and plant-based products have been used for a long time for medicinal purposes. This study aimed to determine the antioxidant and anti-α-glucosidase activities of eight selected underutilized plants in Malaysia: Leucaena leucocephala, Muntingia calabura, Spondias dulcis, Annona squamosa, Ardisia elliptica, Cynometra cauliflora, Ficus auriculata, and Averrhoa bilimbi. This study showed that the 70% ethanolic extract of all plants exhibited total phenolic content (TPC) ranging from 51 to 344 mg gallic acid equivalent (GAE)/g dry weight. A. elliptica showed strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO) scavenging activities, with half maximal inhibitory concentration (IC50) values of 2.17 and 49.43 μg/mL, respectively. Most of the tested plant extracts showed higher inhibition of α-glucosidase enzyme activity than the standard, quercetin, particularly A. elliptica, F. auriculata, and M. calabura extracts with IC50 values of 0.29, 0.36, and 0.51 μg/mL, respectively. A total of 62 metabolites including flavonoids, triterpenoids, benzoquinones, and fatty acids were tentatively identified in the most active plant, i.e., A. elliptica leaf extract, by using ultra-high-performance liquid chromatography (UHPLC)-electrospray ionization (ESI) Orbitrap MS. This study suggests a potential natural source of antioxidant and α-glucosidase inhibitors from A. elliptica.
Increasing evidence from both experimental and clinical studies depicts the involvement of oxidative stress in the pathogenesis of various diseases. Specifically, disruption of homeostatic redox balance in accumulated body fat mass leads to obesity-associated metabolic syndrome. Strategies for the restoration of redox balance, potentially by exploring potent plant bioactives, have thus become the focus of therapeutic intervention. The present study aimed to bioprospect the potential use of the curculigoside-cinnamic acid-rich fraction from Molineria latifolia rhizome as an antioxidant therapeutic agent. The ethyl acetate fraction (EAF) isolated from M. latifolia rhizome methanolic extract (RME) contained the highest amount of phenolic compounds, particularly curculigoside and cinnamic acid. EAF demonstrated glycation inhibitory activities in both glucose- and fructose-mediated glycation models. In addition, in vitro chemical-based and cellular-based antioxidant assays showed that EAF exhibited high antioxidant activities and a protective effect against oxidative damage in 3T3-L1 preadipocytes. Although the efficacies of individual phenolics differed depending on the structure and concentration, a correlational study revealed strong correlations between total phenolic contents and antioxidant capacities. The results concluded that enriched phenolic contents in EAF (curculigoside-cinnamic acid-rich fraction) contributed to the overall better reactivity. Our data suggest that this bioactive-rich fraction warrants therapeutic potential against oxidative stress-related disorders.
Blechnum orientale Linn. (Blechnaceae) is used ethnomedicinally for the treatment of various skin diseases, stomach pain, urinary bladder complaints and sterilization of women. The aim of the study was to evaluate antioxidant, anticancer and antibacterial activity of five solvent fractions obtained from the methanol extract of the leaves of Blechnum orientale Linn.
A computer-aided predictions of antioxidant activities were performed with the Prediction Activity Spectra of Substances (PASS) program. Antioxidant activity of compounds 1, 3, 4 and 5 were studied using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and lipid peroxidation assays to verify the predictions obtained by the PASS program. Compounds 3 and 5 showed more inhibition of DPPH stable free radical at 10⁻⁴ M than the well-known standard antioxidant, butylated hydroxytoluene (BHT). Compound 5 exhibited promising in vitro inhibition of Fe²⁺-induced lipid peroxidation of the essential egg yolk as a lipid-rich medium (83.99%, IC₅₀ 16.07 ± 3.51 μM/mL) compared to α-tocopherol (α-TOH, 84.6%, IC₅₀ 5.6 ± 1.09 μM/mL). The parameters for drug-likeness of these BHT analogues were also evaluated according to the Lipinski’s “rule-of-five” (RO5). All the BHT analogues were found to violate one of the Lipinski’s parameters (LogP > 5), even though they have been found to be soluble in protic solvents. The predictive polar surface area (PSA) and absorption percent (% ABS) data allow us to conclude that they could have a good capacity for penetrating cell membranes. Therefore, one can propose these new multipotent antioxidants (MPAOs) as potential antioxidants for tackling oxidative stress and lipid peroxidation processes.
This study investigates the characteristics of an antioxidant cream made from the methanol extract of Piper sarmentosum leaves, which is locally known as the wild betel or pokok kadok in Malay. The secondary metabolites of the leaves were subjected to phytochemical tests to detect the presence of natural compounds. Antioxidant activity was described by its total phenolic content (TPC) and total flavonoid content (TFC), which was assessed by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay. A phase diagram was constructed to find a possible region to formulate an antioxidant cream. In phytochemical screening, the methanolic extract showed positive presence of alkaloids, flavonoids, steroids, terpenoids and tannins. In quantitative analysis of antioxidative components, besides having significantly higher TFC content compared with quercetin (P
In the current study, changes in secondary metabolite synthesis and the pharmaceutical quality of sabah snake grass leaves and buds were considered in relation to plant age (1 month, 6 months, and 1 year old). The activity of the enzyme chalcone synthase (CHS, EC 2.3.1.74) was measured, as it is a key enzyme for flavonoid production. Significant differences in total flavonoid (TF) production were observed between the three plant growth periods and the different plant parts. The highest contents of TF (6.32 mg/g dry weight [DW]) and total phenolic (TP) (18.21 mg/g DW) were recorded in 6-month-old buds. Among the flavonoids isolated in this study the most important ones based on concentration were from high to low as follows: catechin > quercetin > kaempferol > luteolin. Production of phenolic acids increased from 1 to 6 months, but after 6 months up to 1 year of age, they decreased significantly. The highest contents of caffeic acid (0.307 mg/g DW) and gallic acid (5.96 mg/g DW) were recorded in 1-year and 6-month-old buds, respectively. The lowest and highest activity of CHS was recorded in 1-month and 6-month-old buds with values of 3.6 and 9.5 nkat/mg protein, respectively. These results indicate that the increment in flavonoids and phenolic acids in 6-month-old buds can be attributed to an increase in CHS activity. The highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) activity was observed in the extract of 1-year-old buds followed by 6-month-old buds, with 50% of free radical scavenging (IC50) values of 64.6 and 73.5 µg/mL, respectively. Interestingly, a ferric reducing antioxidant power (FRAP) assay showed a higher activity in 6-month-old buds (488 μM of Fe(II)/g) than in 1-year-old buds (453 μM of Fe(II)/g), in contrast to the DPPH result. Significant correlations (p < 0.05) were observed between CHS enzyme activity and FRAP activity, TF, catechin, and kaempferol content. Extracts of 6-month-old bud exhibited a significant in vitro anticancer activity against HeLa cancer cells with IC50 value of 56.8 µg/mL. These results indicate that early harvesting of snake grass (6-month-old) may yield increased concentrations of secondary metabolites, which are potent antioxidant compounds.
Peperomia pellucida leaf extract was characterized for its anticancer, antimicrobial, antioxidant activities, and chemical compositions. Anticancer activity of P. pellucida leaf extract was determined through Colorimetric MTT (tetrazolium) assay against human breast adenocarcinoma (MCF-7) cell line and the antimicrobial property of the plant extract was revealed by using two-fold broth micro-dilution method against 10 bacterial isolates. Antioxidant activity of the plant extract was then characterized using α, α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging method and the chemical compositions were screened and identified using gas chromatography-mass spectrometry (GC-MS). The results of present study indicated that P. pellucida leaf extract possessed anticancer activities with half maximal inhibitory concentration (IC(50)) of 10.4 ± 0.06 µg/ml. The minimum inhibitory concentration (MIC) values were ranged from 31.25 to 125 mg/l in which the plant extract was found to inhibit the growth of Edwardsiella tarda, Escherichia coli, Flavobacterium sp., Pseudomonas aeruginosa and Vibrio cholerae at 31.25 mg/l; Klebsiella sp., Aeromonas hydrophila and Vibrio alginolyticus at 62.5 mg/l; and it was able to control the growth of Salmonella sp. and Vibrio parahaemolyticus at 125 mg/l. At the concentration of 0.625 ppt, the plant extract was found to inhibit 30% of DPPH, free radical. Phytol (37.88%) was the major compound in the plant extract followed by 2-Naphthalenol, decahydro- (26.20%), Hexadecanoic acid, methyl ester (18.31%) and 9,12-Octadecadienoic acid (Z,Z)-, methyl ester (17.61%). Findings from this study indicated that methanol extract of P. pellucida leaf possessed vast potential as medicinal drug especially in breast cancer treatment.
Plant essential oils are widely used as fragrances and flavours. Therefore, the essential oils from the leaves of Cinnamomum pubescens Kochummen (CP) and the whole plant of Etlingera elatior (EE) were investigated for their antioxidant, antibacterial and phytochemical properties.
This study was designed to investigate the antioxidant and antimicrobial activities of the essential oils from Piper officinarum C. DC. GC and GC/MS analysis of the leaf and stem oils showed forty one components, representing 85.6% and 93.0% of the oil, respectively. The most abundant components in the leaf oil were beta-caryophyllene (11.2%), alpha-pinene (9.3%), sabinene (7.6%), beta-selinene (5.3%) and limonene (4.6%), while beta-caryophyllene (10.9%), alpha-phellandrene (9.3%), linalool (6.9%), limonene (6.7%) and alpha-pinene (5.0%) were the main components of the stem oil. The antioxidant activities were determined by using complementary tests: namely beta-carotene-linoleic acid, DPPH radical scavenging and total phenolic assays. The stems oil showed weak activity (IC50 = 777.4 microg/mL) in the DPPH system, but showed moderate lipid peroxidation inhibition in the beta-carotene-linoleic acid system (88.9 +/- 0.35%) compared with BHT (95.5 +/- 0.30%). Both oils showed weak activity against P. aeruginosa and E. coli with M IC values of 250 microg/mL.
The chemical composition of the essential oil of Knema kunstleri Warb. (Myristicaceae) was investigated for the first time. The essential oil was obtained by hydrodistillation and fully characterized by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). In total, 36 components were identified in the essential oil, which made up 91.7% of the total oil. The essential oil is composed mainly of β-caryophyllene (23.2%), bicyclogermacrene (9.6%), δ-cadinene (7.3%), α-humulene (5.7%), and germacrene D (4.3%). The essential oil showed moderate activity towards DPPH free-radical scavenging and lipoxygenase inhibition. To the best of our knowledge, this is the first study of the composition and bioactivities of the essential oil report concerning the genus Knema.
Three main types of PVC solvent polymeric membrane ion-selective electrodes for chloroquine are described. They are based on three ion-pairing agents namely dipicrylamine (DPA), tetraphenylborate (TPB) or tetrakis(4-chlorophenyl)borate (TCPB) with either dioctylphenyl phosphonate (DOPP) or trioctyl phosphate (TOP) solvent mediator. All electrodes exhibit Nernstian responses, fast dynamic response times and a wide useful pH range. The best all-round electrode is based on TPB and TOP plasticizing solvent mediators with a limit of detection of 7.1 x 10(-6)M and was utilized for the assay of chloroquine in tablets. Direct potentiometric determinations with either the analyte addition method or the normal calibration method gave results comparable to the official method.
A preliminary study was conducted to study the effects of different types and concentrations of co-solvents based on yield, composition and antioxidants capacity of extract prior to optimization studies of supercritical fluid extraction (SFE) of Labisia pumila (locally referred to as 'kacip fatimah'). The following co-solvents were studied prior to the optimization of supercritical carbon dioxide (SC-CO2) technique: ethanol, water, methanol, as well as aqueous solutions of ethanol-water and methanol-water (50% and 70% v/v). By using the selected co-solvents, identification of phenolic acids (gallic acid, methyl gallate and caffeic acid) was determined by using High-Performance Liquid Chromatography (HPLC). Then, the antioxidant capacity was evaluated by using three different assays: total phenolic content (TPC), ferric reducing/antioxidant power (FRAP) and free radical-scavenging capacity of 2,2-diphenyl-1-picrylhydrazyl (DPPH). SC-CO2 with 70% ethanol-water co-solvent was superior in terms of a higher combination of phenolic compounds extracted and antioxidants capacity. Overall, SC-CO2 with co-solvent 70% ethanol-water technique was efficient in extracting phenolic compounds from L. pumila, and thus the usage of this solvent system should be considered for further optimization studies.
The genus Silene is renowned in Turkey for its traditional use as food and medicine. Currently, there are 138 species of Silene in Turkey, amongst which have been several studies for possible pharmacological potential and application in food industry. However, there is currently a paucity of data on Silene salsuginea Hub.-Mor. This study endeavours to access its antioxidant, enzyme inhibitory, and anti-inflammatory properties. Besides, reversed-phase high-performance liquid chromatography-diode array detector (RP-HPLC-DAD) was used to detect phenolic compounds, and molecular docking was performed to provide new insights for tested enzymes and phenolics. High amounts of apigenin (534 μg/g extract), ferulic acid (452 μg/g extract), p-coumaric acid (408 μg/g extract), and quercetin (336 μg/g extract) were detected in the methanol extract while rutin (506 μg/g extract) was most abundant in the aqueous extract. As for their biological properties, the methanol extract exhibited the best antioxidant effect in the DPPH and CUPRAC assays, and also the highest inhibition against tyrosinase. The aqueous extract was the least active enzyme inhibitor but showed the highest antioxidant efficacy in the ABTS, FRAP, and metal chelating assays. At a concentration of 15.6 μg/mL, the methanol extract resulted in a moderate decrease (25.1%) of NO production in lipopolysaccharide-stimulated cells. Among the phenolic compounds, epicatechin, (+)-catechin, and kaempferol showed the highest binding affinity towards the studied enzymes in silico. It can be concluded that extracts of S. salsuginea are a potential source of functional food ingredients but need further analytical experiments to explore its complexity of chemical compounds and pharmacological properties as well as using in vivo toxicity models to establish its maximum tolerated dose.
The present study aims to assess the antioxidant activities (AOA) and total phenolic content (TPC) of water extracts of selected edible wild mushrooms: Pleurotus porrigens, Schizophyllum commune, Hygrocybe conica, and Lentinus ciliatus. The AOA were evaluated against DPPH radical and ABTS radical cation scavenging ability, ferric-reducing antioxidant power (FRAP) and beta-carotene-linoleate bleaching (beta-CB) assays, and the Folin-Ciocalteu method for TPC. BHA was used as reference. P. porrigens showed significantly higher (p < 0.05) DPPH* scavenging ability (90.78 +/- 0.30%) and FRAP (6.37 +/- 0.22 mM FE/100g), while Sch. commune showed significantly higher (p < 0.05) ABTS*+ inhibition activity (94.96 +/- 0.70%) and beta-CB inhibition activity (94.18 +/- 0.17%), respectively. TPC was found in a descending order of P. poriggens > L. ciliatus = Pleurotus ostreatus (cultivated) > H. conica = Sch. commune. Positive correlation was observed between the AOA and TPC. When compared to BHA (2 mM), P. porrigens showed significantly higher (p < 0.05) DPPH* scavenging ability and reducing power, while Sch. commune showed comparable DPPH* scavenging ability and ABTS*+ inhibition activity. All the mushrooms have better ABTS*+ inhibition activity than BHA (1 mM). The beta-CB inhibition activity of BHA was significantly higher than those of edible wild mushrooms. The water extracts of edible wild mushrooms showed potent antioxidant activities compared to BHA to a certain extent.
'Mato Peiyu' pomelo (Citrus grandis (L.) Osbeck 'Mato Peiyu') leaves from pruning are currently an agricultural waste. The aim of this study was to isolate essential oils from these leaves through steam distillation (SD) and solvent-free microwave extraction (SFME) and to evaluate their applicability to skin care by analyzing their antimicrobial, antioxidant (diphenyl-1-picrylhydrazyl scavenging assay, β-carotene/linoleic acid assay, and nitric oxide scavenging assay), anti-inflammatory (5-lipoxygenase inhibition assay), and antityrosinase activities. The gas chromatography-mass spectrometry results indicated that the main components of 'Mato Peiyu' leaf essential oils were citronellal and citronellol, with a total percentage of 50.71% and 59.82% for SD and SFME, respectively. The highest bioactivity among all assays was obtained for 5-lipoxygenase inhibition, with an IC50 value of 0.034% (v/v). The MIC90 of the antimicrobial activity of essential oils against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans ranged from 0.086% to 0.121% (v/v). Citronellal and citronellol were the main contributors, accounting for at least 54.58% of the essential oil's bioactivity. This paper is the first to report the compositions and bioactivities of 'Mato Peiyu' leaf essential oil, and the results imply that the pomelo leaf essential oil may be applied in skin care.
(1)H NMR evidence for direct coordination between the Ln(III) ion and the oxygen atoms of the pentaethylene glycol (EO5) ligand and the picrate anion (Pic) in [Ln(Pic)(2)(EO5)][Pic] {Ln=Ce and Nd} complexes are confirmed by single X-ray diffraction. No dissociation of Ln-O bonds in dimethyl sulfoxide-d solution was observed in NMR studies conducted at different temperatures ranging 25-100 degrees C. The Ln(III) ion was chelated to nine oxygen atoms from the EO5 ligand in a hexadentate manner and the two Pic anions in each bidentate and monodentate modes. Both compounds are isostructural and crystallized in monoclinic with space group P2(1)/c. Coordination environment around the Ce1 and Nd1 atoms can be described as tricapped trigonal prismatic and monocapped square antiprismatic geometries, respectively. The crystal packing of the complexes have stabilized by one dimensional (1D) chains along the [001] direction to form intermolecular O-Hcdots, three dots, centeredO and C-Hcdots, three dots, centeredO hydrogen bonding. The molar conductance of the complexes in DMSO solution indicated that both compounds are ionic. The complexes had a good thermal stability. Under the UV-excitation, these complexes exhibited the red-shift emission.