Ferric Reducing Properties Research Articles

Antioxidant activity of Sophora exigua and liposome development of its powerful extract.

Sophora exigua (SE) was sequentially extracted using hexane, ethyl acetate, and ethanol. The obtained extracts were tested for antioxidant activity. Among them, the fractionated ethyl acetate extract (SE-EA) showed the highest potential in free radical scavenging and ferric-reducing properties. The chemical analysis identified sophoraflavanone G as one of the active ingredients in SE-EA. According to SE-EA solubility, SE-EA liposomes were developed using a sonication-assisted thin film method. Cholesterol and phospholipids were used as the main compositions of the liposomes. The obtained liposomes were spherical with different nano-size ranges, size distribution, and zeta potential depending on SE-EA and total lipid concentrations. SE-EA liposomes were slightly bigger than their empty liposomes. All liposomes exhibited a phospholipid crystalline structure. Cholesterol and SE-EA existed in the liposomes as an amorphous state. SE-EA liposomes with high total lipid content exhibited high entrapment efficiency and sustained release behavior. Whereas liposomes with low total lipid content showed low entrapment efficiency and fast-release behavior. All SE-EA liposomes showed stronger antioxidant activity than the non-entrapped SE-EA. In conclusion, SE-EA is a natural source of potent antioxidants. The developed SE-EA liposomes are a promising pharmaceutical formulation to efficiently deliver the active ingredients of SE-EA and are suitable for further study in vivo.

SYNTHESIS AND ANTIOXIDANT ACTIVITY OF THIADIAZINE DERIVATIVES WITH PHENOLIC FRAGMENTS

A series of thiocarbohydrazones based on 3,5-di-tert-butyl-4-hydroxybenzaldehyde, salicylaldehyde, vanillin and 4,6-di-tert-butyl-2,3-dihydroxybenzaldehyde were synthesized. The reaction between thiocarbohydrazones and bromoacetylcoumarin was used to obtain and characterize a number of thiadiazine derivatives containing a phenolic fragment. The yields were 56–90%. The structural properties of the synthesized substances were studied by IR-Fourier, 1H, 13C NMR spectroscopy. In the IR spectra of thiadiazines there are characteristic bands of the stretching vibrations of the OH group (3622 cm-1), N-H bond (3450 cm-1), double bonds C=C and C=N 1608 and 1541 cm-1, respectively. In contrast to the spectrum of the starting compounds, there is a peak corresponding to vibrations of the C=O bond (1722 cm-1), which appeared due to the coumarin fragment. The 1Н NMR spectra of the obtained compounds contain peaks at 3.9 ppm, corresponding to the protons of the thiadiazine fragment. There are no signals at 6.8 ppm, related to the CH proton of the thiazole ring, and there is also a set of peaks in the region of 7.5-8.4 ppm., characteristic of the coumarin ring. Antioxidant activity of all products was determined in vitro: radical cation inhibition activity was determined using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) and electron donating activity was determined by ferric reduction ability using the ferricyanide/Prussian blue method. In both cases, agidol was used as a standard. All tested substances showed higher activity in both tests compared to the standard. The best antioxidant properties in both methods were shown by the derivative of 4,6-di-tert-butyl-2,3-dihydroxybenzaldehyde, thiadiazine based on salicylaldehyde also showed high antiradical activity, and thiadiazine with a fragment of 2-methoxyphenol showed good ferric-reducing properties.

Antioxidant properties, antioxidant minerals and vitamins composition of sorghum-carrot agidi enriched with Terminalia catappia L seed flour

Agidi is a thick gel-like fermented food made from cereal pastes; it serves as a major complementary food for infants in many parts of West Africa. The aim of this work was to investigate the nutritional and antioxidant properties of sorghum-carrot agidi enriched with Terminalia catappia seed flours. The composition of minerals (Cu, Zn, Fe, Mn) and Vitamins (A, B1, B2, B12, D and E) in the sorghum based agidi samples were analyzed using standard protocol. The antioxidant properties of the agidi samples were determined by Ferric Reducing Properties (FRAP), Free Radical Scavenging Ability (DPPH), Hydroxyl Radical Scavenging Ability (OH) and Fe2+ chelating (Fe2+). The results showed that iron content of the agidi samples ranged from 0.754±0.066 to 1.363±0.069ppm while the Zinc content of the samples were between 0.756±0.030 to 1.96±0.015 ppm. The Vitamin A content of the Agidi samples was between 21.77 – 41.78 mcg RAE while that of Vitamins B1and B2 were 0.0773 – 1.39μg/g. The enriched Agidi sample J5 had the highest values of Vitamins D and E, 1.20 and 1.35μg/g respectively. The antioxidant properties determined showed FRAP values ranged from 3.265±0.026 μg/g to 26.460±0.026 μg/g, DPPH values were between 78.976±0.168 to 87.976±0.168% and sample J4 had the highest Fe2+ chelation values 29.545±0.267%. The vitamins and minerals composition of the sorghum agidi samples were enhanced significantly (P<0.05) by enrichment with carrot and tropical almond seed flours and this was reciprocated in theirantioxidant potencies.

Antioxidant, Antimicrobial, Cytotoxicity, and Larvicidal Activities of Selected Synthetic Bis-Chalcones

Plants are known to have numerous phytochemicals and other secondary metabolites with numerous pharmacological and biological properties. Among the various compounds, polyphenols, flavonoids, anthocyanins, alkaloids, and terpenoids are the predominant ones that have been explored for their biological potential. Among these, chalcones and bis-chalcones are less explored for their biological potential under in vitro experiments, cell culture models, and animal studies. In the present study, we evaluated six synthetic bis-chalcones that were different in terms of their aromatic cores, functional group substitution, and position of substitutions. The results indicated a strong antioxidant property in terms of DPPH and ABTS radical-scavenging potentials and ferric-reducing properties. In addition, compounds 1, 2, and 4 exhibited strong antibacterial activities against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella enteritidis. The disc diffusion assay values were indicative of the antibacterial properties of these compounds. Overall, the study indicated the antioxidant and antimicrobial properties of the compounds. Our preliminary studies point to the potential of this class of compounds for further in vivo investigation.

Evaluation of Physicochemical Properties and Sensory Attributes of Pumpkin Seed (Cucurbita maxima) Bouillon Cube

ABSTRACT The physicochemical properties and consumer acceptability of bouillon cubes prepared from fermented pumpkin seed flour were evaluated. The results from microbial identified Bacillus subtilis as the main bacterium responsible for the production of condiment from pumpkin seed. Pumpkin bouillon cubes were observed to be rich in protein content (40.32–44.06%), energy value (521.57–538.49 kcal/100 g), potassium (859. 50–1128.00 mg/kg), phosphorous (402.27–501.87 mg/kg) and calcium (30.20–40.97 mg/kg). The result of the phytochemical properties of the pumpkin bouillon cubes include, tannin (1.94 mg/g − 2.92 mg/g), oxalate (2.78 mg/g − 3.45 mg/g), saponin (2.06 mg/g − 2.87 mg/g), phytate (4.45 mg/g − 5.44 mg/g), and alkaloid (2.40 mg/g − 3.58 mg/g). Free radical scavenging against 1, 1- diphenyl-2-picryhydrazyl (DPPH) (67.09%-88.03%), ferric reducing property (FRAP) (58.61 mg/g-63.10 mg/g) and Iron II chelation (44.78 mg/g-56.10 mg/g) of the bouillon cubes were found to increase with increase in amount of fermented pumpkin seed. The results further showed that aqueous extracts of pumpkin bouillon cube exhibited strong α-amylase (46.21%-51.08%) and α–glucosidase (67.87%-88.13%) inhibitory activities. Pumpkin bouillon cubes made from 80% fermented pumpkin seed was well accepted as seasoning and compete favorably with the control.

Phytochemical profiling of Azima tetracantha Lam. leaf methanol extract and elucidation of its potential as a chain-breaking antioxidant, anti-inflammatory and anti-proliferative agent.

Azima tetracantha, a traditional medicinal plant included in the order Brassicales and family Salvadoraceae, is widely used as a dietary supplement in folklore medicines. The plant is also used for the treatment of rheumatism, diarrhea and other inflammatory disorders. The present investigation focused on the phytochemical composition, radical scavenging, reducing potential and anti-proliferative activities of the A. tetracantha leaves. Quantitative estimation of the polyphenols and flavonoids revealed significantly elevated levels in the methanol extract. Corroborating with this, methanol extract exhibited higher in vitro anti-radical scavenging effect against 2,2-diphenyl-1- picrylhydrazyl (34.14 ± 2.19 μg/mL), and hydrogen peroxide (44.96 ± 1.77 μg/mL), as well as ferric reducing properties (58.24 ± 6.98 μg/mL). The methanolic extract also showed strong lipoxygenase (71.42 ± 6.36 μg/mL) and nitric oxide inhibitory activities (94.23 ± 8.11 μg/mL). Cytotoxic activity against MCF7 cells was found to be higher (IC50= 37.62 ± 2.94 μg/mL), than that of MDAMB231 cells (IC50= 69.11 ± 5.02 μg/mL). The qPCR-based analysis indicated dose-dependent increase in the expression of the pro-apoptotic genes such as executioner caspases and apoptotic protease activating factor-1. Overall, the results indicated the possible use of methanol extract of A. tetracantha leaves as a chain-breaking antioxidant molecule and are capable of inhibiting inflammatory enzymes and the proliferative potential of breast cancer cells.

Comparative effects of berberine and piperine on the neuroprotective potential of neostigmine

This study examined effect of berberine and piperine on neuroprotective potential of neostigmine in the management of neurological disorders. Berberine and neostigmine were weighed (30g), dissolved in distilled water (30mL) separately, while, 30mg piperine was dissolved in ethanol (0.45mL), made up to 30mL with distilled water. Antioxidant activities in 2, 2-diphenyl-1-picrylhydrazyl radical (DPPH), 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonate) radical (ABTS), Fe-chelation, ferric reducing properties (FRAP), nitric oxide (NO) and hydroxyl (OH) radical scavenging abilities and Fe2+, cisplatin and sodium nitroprusside (SNP) induced lipid peroxidation (LPO), and acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and monoamine oxidase (MAO) activities were assessed in vitro. The result revealed that tested compounds inhibited enzymes activities dose-dependently. However, berberine (IC50=0.17mg/mL) had slight higher AChE inhibitory effect than piperine and neostigmine (p<0.05). Also, berberine had the highest BChE inhibitory effect (IC50=0.16mg/mL) while piperine exhibited the highest MAO inhibitory effect (IC50=0.21mg/mL). Berberine, piperine and neostigmine exhibited high antioxidant properties and inhibited Fe2+, cisplatin and SNP induced LPO. Both alkaloids demonstrated antiradical scavenging ability comparable to neostigmine action against Alzheimer's disease (AD). The modulatory and antioxidant berberine and piperine properties on these enzymes (AChE, BChE and MAO) could be possible underlying mechanisms in employing these compounds as a complementary therapy in neurodegenerative diseases (NDDs) management.

Optimization of starch-based candy supplemented with date palm (Phoenix dactylifera) and tamarind (Tamarindus indica L.)

The various health challenges posed by conventional candies necessitate the development of health-promoting and phytochemicals supplemented varieties. The current study explored medicinal properties of date palm and tamarind in the formulation of a starch-based candy, using response surface method for the production optimization. Experimental design variables include the starch (90–100%), date palm (0–10%), and tamarind (0–10%), while the functional, phytochemical, and antioxidant properties were the responses. The candy modification response results are as follows: pH (2.80–3.00), crude fibre (4.41–6.43%), soluble sugar (91.69–126.96%), total titrable acidity (90.00–120.00%), total phenolics (0.039–0.063 mg GA/mL), total flavonoids (0.0006–0.001 mg RU/mL), vitamin C (0.362–0.516 mg/mL), hydroxyl radical scavenging activities (14.28–26.67%), 1, 1- diphenyl-2-picryhydrazyl (1.12–3.88%) and ferric reducing property (0.09–0.31 mg/mL). The experiments revealed that most of the nutritional properties of the candies increased favorably with the incorporation of date palm and tamarind pulps and decreasing starch content. Significant (p ≤ 0.05) interactive effects were revealed between the diverse variables. The experiments also revealed the positive influence of the date palm and tamarind fruit pulps on the functional, phytochemical, and antioxidant properties of starch-based candies; hence demonstrating the possibility of developing nutraceutical based-candies with a more beneficial health effect.

Phytochemical Screening and in vitro Antioxidant Properties of Methanol and Aqueous Leaf Extracts of Geophila obvallata

Aim: This study investigated the phytochemical constituents and in vitro antioxidant properties of methanol and aqueous leaf extracts of Geophila obvallata using standard methods.&#x0D; Materials and Methods: The in vitro antioxidant assays carried out were 1, 1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging ability, Nitric oxide (NO•) radical scavenging activity assay, 2, 2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS•+) radical cation scavenging assay, ferric reducing properties and hydroxyl radical scavenging assays.&#x0D; Results: Phytochemical analysis revealed the presence of alkaloids, flavonoids, phenolic compounds, steroids, saponins, terpernoids and cardiac glycosides in both extracts. Relative to the aqueous extract, the methanol extract contained a higher amount of the secondary metabolites. However, both extracts exhibited appreciable and dose-dependent capacities for quenching DPPH, ABTS•+ and NO• free radicals, and potent ferric reducing ability to levels comparable to those of ascorbic acid. The crude methanol extract showed significantly increased (P&lt;0.05) antioxidant activity than the aqueous extract.&#x0D; Conclusion: It was concluded that the extract possesses strong antioxidant properties due to its content of phytochemicals, and provides scientific basis for its ethno medicinal applications.

Modulatory effect of caffeic acid on cholinesterases inhibitory properties of donepezil.

Background Donepezil hydrochloride commonly used in the management of Alzheimer's disease (AD), exhibiting its inhibitory effects on acetylcholinesterase and butyrylcholinesterase activity thereby enhance cognitive function. Caffeic acid member of hydroxycinnamic acid is widely present in human diet. This study aims to investigate influence of caffeic acid on acetylcholinesterase and butyrylcholinesterase inhibitory properties of donepezil (in vitro). Methods 5 mg of donepezil was dissolved in 50 mL distilled water while 10 mg of caffeic acid was dissolved in 100 mL distilled water. Therefore, mixtures of samples were prepared as follows: A2=donepezil 0.075 mg/mL+caffeic acid 0.025 mg/mL; A3=donepezil 0.050 mg/mL+caffeic acid 0.050 mg/mL; A4=donepezil 0.025 mg/mL+caffeic acid 0.075 mg/mL. All samples were kept in the refrigerator at 4 °C for subsequent analysis. Results The result showed that all the combinations show an inhibitory effect on acetylcholinesterase and butyrylcholinesterase activity in vitro, with the combination A4=donepezil 0.025 mg/mL+caffeic acid 0.075 mg/mL had significant (p<0.05) highest inhibitory effect on acetylcholinesterase and butyrylcholinesterase activity in vitro. More so, all the samples were able to prevent pro-oxidants (FeSO4 and sodium nitroprusside [SNP] ) induced lipid peroxidation in rat brain homogenate, with the combination A4=donepezil 0.025 mg/mL+caffeic acid 0.075 mg/mL and A3=donepezil 0.050 mg/mL+caffeic acid 0.050 mg/mL had highest inhibitory effect against FeSO4 and SNP induced lipid peroxidation in rat brain homogenate in vitro respectively. Moreover, all the samples exhibit antioxidant properties as typified by their ability to chelate iron (II) ion (Fe2+), hydroxyl radical (OH٭) radical scavenging ability and ferric reducing property (FRAP). Conclusions Therefore, the combination of caffeic acid with donepezil enhances the antioxidant properties of donepezil. The combination of caffeic acid with donepezil could be a therapeutic aid in the management of AD, possibly with fewer side effects of donepezil. Nevertheless, the combination donepezil 0.025 mg/mL+caffeic acid 0.075 mg/mL acid look promising.

Proximate composition, phytochemical analysis, and in vitro antioxidant potentials of extracts of Annona muricata (Soursop).

Numerous bioactive compounds and phytochemicals have been reported to be present Annona muricata (Soursop). Some of these chemical compounds have been linked to the ethnomedicinal properties of the plant and its antioxidant properties. The aim of this study was to assess the proximate composition, phytochemical constituents and in vitro antioxidant properties of A. muricata using standard biochemical procedures. The defatted Annona muricata crude methanolic extracts of the different parts of the plant were used for the estimation of proximate composition and phytochemical screening. The crude methanolic extracts of the different parts of the plant were also fractionated using solvent–solvent partitioning. Petroleum ether, chloroform, ethyl acetate, methanol, and methanol‐water (90:10) were the solvents used for the fractionation. The different fractions obtained were then used to perform in vitro antioxidant analyses including, 1, 1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging ability, ferric reducing properties, and hydroxyl radical scavenging ability. The leaf methanolic extract had a higher lipid content, whereas its chloroform fraction demonstrated a better ability to quench DPPH free radical. The root‐bark methanol‐water, leaf methanol, fruit pulp chloroform, and leaf petroleum ether fractions demonstrated potent ferric reducing properties. The leaf and stem‐bark petroleum ether fractions demonstrated better hydroxyl‐free radical scavenging abilities. The leaf and fruit pulp of Annona muricata have a very potent antioxidant ability compared to the other parts of the plant. This can be associated with the rich phytochemicals and other phytoconstituents like phenols, flavonoids, alkaloids, and essential lipids, etc. Significant correlations were observed between the antioxidant status and phytochemicals present. These results thus suggest that some of the reported ethnomedicinal properties of this plant could be due to its antioxidant potentials.

Phytochemical, organoleptic and ferric reducing properties of essential oil and ethanolic extract from Pistacia lentiscus (L.)

ObjectiveTo study the phytochemical composition and organoleptic properties of Pistacia lentiscus (L.) (P. lentiscus) from Algeria and to investigate the antioxidant activities of its essential oil and ethanolic extract. MethodsAerial parts of P. lentiscus were collected at Hammam Melouane (Blida), 50 km from Algiers. Different solvent extractions were made for the preliminary screening of phytochemicals. Additionally, the physicochemical and organoleptic properties of the Algerian variety have been characterized. Moreover, P. lentiscus essential oil and ethanolic extract were studied for their antioxidant potential by ferric reducing power test. ResultsPhytochemical screening of P. lentiscus revealed the presence of various biochemicals, including leuco-anthocyanins, condensed tannins, gallic tannins, saponoside, coumarins, and flavonoids, while others were absent (anthocyanins and alcaloids). Essential oil showed lower antioxidant potential compared to the ethanolic extract, reflecting the potential phenolic content responsible for this activity. ConclusionsThe present study reveals the presence of various phytochemical classes in P. lentiscus, and the antioxidant experiment shows a good bioactivity of the aerial parts of the Algerian P. lentiscus. The literature review of the essential oil composition shows also important variations due to geographic and environmental conditions. This preliminary investigation will help explore the bioactive compounds of P. lentiscus, and will bring data for a better physicochemical and organoleptic classification of the Algerian variety.

&lt;i&gt;In vitro&lt;/i&gt; comparative studies on antioxidant capacities of &lt;i&gt;Gnetum africanum&lt;/i&gt; (“Afang”) and &lt;i&gt;Gongronema latifolium&lt;/i&gt; (“Utazi”) leafy vegetables

This study sought to investigate the antioxidant potentials of aqueous extracts of Gongronema latifolium and Gnetum africanum (Afang) vegetables for the management/prevention of reactive oxygen species (ROS) generated as a result of stress. The total phenol, total flavonoids, ferric reducing property (FRAP), Fe 2+ chelation and antioxidants activities [1,1-diphenyl-2 picrylhdrazyl (DPPH) scavenging ability, and hydroxyl radicals (OH*)] and were determined. Gallic acid was used as standard for total phenol and quercetin as standard for total flavonoid determination. Gnetum africanum extract exhibited higher total phenol, total flavonoid, FRAP, DPPH compared to Gongronema latifolium with higher OH* scavenging ability .The extract chelated Fe 2+ in a concentration-dependent manner from the IC 50 value. The antioxidant activities correlated with its phenol/flavonoid content. In conclusion, both aqueous extracts of Gongronema latifolium (Utazi) and Gnetum africanum (Afang) are rich in phenolic compounds with high antioxidant activity, but Utazi had higher antioxidant activity. Keywords : Vegetables; Antioxidants; Phenols; Reactive Oxygen Species (ROS); Medicinal

Shelf life extension of minimally processed ready-to-cook (RTC) cabbage by gamma irradiation.

Gamma irradiation (0.5-2.5kGy) in combination with low temperature (4-15°C) storage was attempted to increase shelf life of ready-to-cook shredded cabbage wrapped in cling films. A maximum extension in shelf life of 8days, while retaining the microbial and sensory quality, was obtained with an irradiation dose of 2kGy and storage at 10°C. Gamma irradiation also inhibited browning of shredded cabbage at their cut edges resulting in enhanced visual appeal. An increase in total antioxidant activity was observed with respect to DPPH and hydroxyl radical scavenging ability while the nitric oxide radical scavenging activity and ferric reducing property remained unaffected with irradiation. Total phenolic, flavonoid and vitamin C content remained unchanged due to irradiation. No significant migration of additives from cling films into stimulant water was observed up to a radiation dose of 2kGy thus demonstrating the feasibility of such films for above applications.

Enhanced production and extraction of phenolic compounds from wheat by solid-state fermentation with Rhizopus oryzae RCK2012

Antioxidant phenolic compounds (PCs) are gaining popularity day by day for their health promoting properties. Wheat is a very good source of natural antioxidant PCs. In the present study, extraction of PCs was improved by solid-state fermentation (SSF) of wheat by Rhizopus oryzae RCK2012 which helped to release the bound compounds from matrix. Different extraction conditions such as solvent composition (water, methanol, 70% methanol, ethanol, 70% ethanol, acetone and 70% acetone), extraction temperature (30–60°C), extraction time (15–90min) and solid-to-solvent ratio (1:2.5 to 1:20, w/v) have been optimized for the extraction of PCs from R. oryzae fermented wheat. Maximum PCs were extracted by water at 40°C within 45min with solid-to-solvent ratio of 1:15 (w/v). Compositional analysis of PCs was carried out by UPLC and TLC. Improved ABTS+ [2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)] and DPPH (2,2-diphenyl-1-picrylhydrazyl), hydroxyl radical and hydrogen peroxide scavenging capacities, ferric reducing property and in vivo antioxidant capacity using Saccharomyces cerevisiae were observed in case of freeze-dried water extract of fermented wheat as compared to unfermented sample. Hence, SSF could be a promising technology to enhance the production and extraction of phenolic compounds for the design of different functional foods and for the specific use as nutraceuticals.

Water Extractable Phytochemicals from Peppers (Capsicum spp.) Inhibit Acetylcholinesterase and Butyrylcholinesterase Activities and Prooxidants Induced Lipid Peroxidation in Rat Brain In Vitro.

Background. This study sought to investigate antioxidant capacity of aqueous extracts of two pepper varieties (Capsicum annuum var. accuminatum (SM) and Capsicum chinense (RO)) and their inhibitory effect on acetylcholinesterase and butyrylcholinesterase activities. Methods. The antioxidant capacity of the peppers was evaluated by the 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging ability and ferric reducing antioxidant property. The inhibition of prooxidant induced lipid peroxidation and cholinesterase activities in rat brain homogenates was also evaluated. Results. There was no significant difference (P > 0.05) in the total phenol contents of the unripe and ripe Capsicum spp. extracts. Ripe and unripe SM samples had significantly higher (P < 0.05) ABTS* scavenging ability than RO samples, while the ripe fruits had significantly higher (P < 0.05) ferric reducing properties in the varieties. Furthermore, the extracts inhibited Fe2+ and quinolinic acid induced lipid peroxidation in rats brain homogenates in a dose-dependent manner. Ripe and unripe samples from SM had significantly higher AChE inhibitory abilities than RO samples, while there was no significant difference in the BuChE inhibitory abilities of the pepper samples. Conclusion. The antioxidant and anticholinesterase properties of Capsicum spp. may be a possible dietary means by which oxidative stress and symptomatic cognitive decline associated with neurodegenerative conditions could be alleviated.

Essential Oil from Lemon Peels Inhibit Key Enzymes Linked to Neurodegenerative Conditions and Pro-oxidant Induced Lipid Peroxidation

This study sought to investigate the effects of essential oil from lemon (Citrus limoni) peels on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities in vitro. The essential oil was extracted by hydrodistillation, dried with anhydrous Na2SO4 and characterized using gas chromatography. Antioxidant properties of the oil and inhibition of pro-oxidant-induced lipid peroxidation in rats brain homogenate were also assessed. The essential oil inhibited AChE and BChE activities in a concentration-dependent manner. GC analysis revealed the presence of sabinene, limonene, α-pinene, β-pinene, neral, geranial, 1,8-cineole, linalool, borneol, α-terpineol, terpinen-4-ol, linalyl acetate and β-caryophyllene. Furthermore, the essential oil exhibited antioxidant activities as typified by ferric reducing property, Fe(2+)-chelation and radicals [DPPH, ABTS, OH, NO] scavenging abilities. The inhibition of AChE and BChE activities, inhibition of pro-oxidant induced lipid peroxidation and antioxidant activities could be possible mechanisms for the use of the essential oil in the management and prevention of oxidative stress-induced neurodegeneration.

Evaluation of the antioxidant activity of several naturally occurring coumarins and their synthesized analogues by “ferric reducing antioxidant power” assay

Coumarins have attracted intense interest in recent years because of their diverse pharmacological properties. According to our continuing investigations of biological effects of several coumarins, the structure–antioxidant activity relationships (SARs) of six naturally occurring coumarins and their 16 synthesized analogues were established. For this purpose, the very reliable colorimetric assay (ferric reducing antioxidant power) modified to be used in 96-well microplates was used. This approach, which determines the reducing capacity of tested compounds directly, has previously been used for the determination of SARs of flavonoids, but has not been used for SAR determination of coumarins. It is known that the biological properties and consequently, therapeutic application of simple coumarins depends upon the pattern of substitution. It was established that 7,8-dihydroxy- and 6,7-dihydroxy-4-methylcoumarins have shown excellent ferric-reducing properties.

Antioxidant properties of cold and hot water extracts of cocoa, Hibiscus flower extract, and ginger beverage blends

Beverages with bioactive compounds are consumed for their food value, thirst quenching ability and the health benefit they confer on consumers. Hot and cold cocoa:Hibiscus-flower-extract:ginger beverages were prepared in the laboratory. These ready-to-drink beverages were evaluated nutritionally for their antioxidant properties. The cold and hot water extracts of the beverages contained total phenolic content ranging from 11.61 to 22.01mg GAE/g; the ferric reducing property ranged from 10.84 to 26.88mg/g, while the vitamin C content ranged from 1.77 to 4.82mg/g. The DPPH inhibition by the cold and hot water extracts of the beverages ranged from 38.60 to 87.53%. The ABTS scavenging ability was the lowest in the ginger extract with no significant differences among the other blends. Both 100% cocoa and 100% Hibiscus-flower-extract have high antioxidant properties and their combined effect increased the free radical scavenging potentials of the beverages. The cocoa–zobo–ginger beverage mixtures all have complimentary effect thus possessing high antioxidant activities.

Antioxidant potentials of various solvent extracts from stem bark of &amp;lt;i&amp;gt;Enantia chlorantha&amp;lt;/i&amp;gt;

The stem bark of Enantia chlorantha is commonly used for the treatment of malaria and other ailments of the human body such as cough and wound. The plant had been intensely studied for its antimicrobial activities and antipyretic properties. However, the efficacy and mechanisms of action of the plant remain unclear. Therefore, the objective of the present study was to determine the in vitro antioxidant activity of the various solvent extracts from stem bark of Enantia chlorantha. In vitro antioxidant activity of certain extracts of stem bark of Enantia chlorantha such as methanol extract (ME), n-hexane, chloroform, ethylacetate, and aqueous fractions (HF, CF, EF and AF respectively) was evaluated using models of DPPH radical scavenging activity, ferric reducing property (FRAP), nitric oxide scavenging activity, hydroxyl radical scavenging activity. The inhibition of lipid oxidation, total flavonoids and phenolic contents of the extracts were also determined using spectrophotometric methods. The result revealed the highest phenolic and flavonoid contents in the methanol extract followed by AF, EF and CF while HF contained the least concentration. Free radical scavenging potentials of the extracts were found to be proportional to their respective phenolic and flavonoid contents. Our results suggest that part of the mechanisms through which the plant is used in folk medicine for the treatment of stress related diseases such as malaria, and cough and wound may be through its antioxidant activity, DPPH, nitric oxide , hydroxyl radical scavenging abilities and reducing power.