High Antioxidant Action Research Articles

Bioactivity and antidiabetic properties of Malva parviflora L. leaves extract and its nano-formulation in streptozotocin-induced diabetic rats

Diabetes is a drastic health problem resulting from an endocrine disorder. M. parviflora L. might represent an antioxidant-rich food source and thus applies to pharmaceutical and therapeutic applications in oxidative stress-related degenerative diseases. In the current work, we assessed the antidiabetic activity of M. parviflora L. leaves extract and its nano-formulation in rats. M. parviflora L. bioactivity was evaluated by both antioxidant and antimicrobial assays. The nano-formulation characteristics (Mass, TEM, and Zeta potential) were evaluated. Twenty-four male Sprague-Dawley rats were administered streptozotocin (STZ) intraperitoneally for only one dose (35 mg/kg body weight). All of the nutritional and biochemical parameters were statistically analyzed. The results showed that M. parviflora L. is rich in phenolics and flavonoids with high antioxidant action. The antifungal activity of the extract was evident, especially with Fusarium culmorum and aspergillus flavus. The extract and its nano-formulation have shown antidiabetic properties when tested on diabetic rats as they improved all the biochemical parameters; decreased glucose level in serum, increased insulin production, marked improvement in lipid profile, liver and kidney functions, and that was more proved with the histopathological examinations. Conclusively, M. parviflora L. extract and its nano-formulation could attenuate or effectively help in controlling diabetes through its therapeutic properties exhibited by the action of the plant antioxidant components.

Cassava starch films incorporated with clove essential oil and nanoclay as a strategy to increase the shelf life of strawberries

SummaryThe incorporation of essential oil and nanocomposites can develop bioplastics with antioxidant and antimicrobial effects that extend the shelf life of food. In this study, active cassava starch films were incorporated with clove essential oil (CEO) and montmorillonite (MMT) for application on fresh strawberries. Central composite design was used in the development of cassava starch active films and the mechanical, barrier, antioxidant and antimicrobial properties were evaluated. The effects of active films on the quality of fresh strawberries were investigated. The incorporation of MMT and CEO promoted better mechanical performance (elongation greater than 180%), greater light barrier properties (opacity greater than 17%) and high antioxidant action due to the content of polyphenols present (32 mg GAE/g). Strawberries packed with the active films showed less changes in the parameters of colour, acidity and microbial contamination during the storage period evaluated.

Technological innovations in the cultivation of Haematococcus pluvialis microalgae: review

The cultivation of microalgae presents a great biotechnological potential, mainly to produce natural bioactive substances, which can be used in the pharmaceutical industry and especially in the development of functional foods, thanks to its nutritional properties. Among the commercially important microalgae, Haematococcus pluvialis is considered the main source of natural astaxanthin, a carotenoid of high antioxidant action and with wide applications in the nutraceuticals, cosmetics, food and aquaculture industries. This review aimed to cover the most important aspects of biology, biochemical composition, biosynthesis and astaxanthin accumulation in the cells of H. pluvialis, in addition to its broad application to humans and animals. The methodology used in this work was a systematic review of the literature, presenting the gaps and opportunities for research. This work provided a broader view of the technologies and methodologies used to produce H. pluvialis, providing a direction for future work to be undertaken. During the bibliographic survey, it was observed that information regarding the cultivation of H. pluvialis, aiming at the production of astaxanthin, is still very incipient in Brazil, with results observed only on a laboratory scale, making it difficult to really understand the implementation costs for a possible commercial production. This work has started a larger research and will serve as a basis for future activities, mainly to solve possible doubts.

The Radioprotective Effect of Procaine and Procaine-Derived Product Gerovital H3 in Lymphocytes from Young and Aged Individuals.

Ionizing radiation induces genomic instability in living organisms, and several studies reported an ageing-dependent radiosensitivity. Chemical compounds, such as scavengers, radioprotectors, and modifiers, contribute to reducing the radiation-associated toxicity. These compounds are often antioxidants, and therefore, in order to be effective, they must be present before or during exposure to radiation. However, not all antioxidants provide radioprotection. In this study, we investigated the effects of procaine and of a procaine-based product Gerovital H3 (GH3) on the formation of endogenous and X-ray-induced DNA strand breaks in peripheral blood mononuclear cells (PBMCs) isolated from young and elderly individuals. Interestingly, GH3 showed the strongest radioprotective effects in PBMCs from young subjects, while procaine reduced the endogenous amount of DNA strand breaks more pronounced in aged individuals. Both procaine and GH3 inhibited lipid peroxidation, but procaine was more effective in inhibiting mitochondria free radicals' generation, while GH3 showed a higher antioxidant action on macrophage-induced low-density lipoprotein oxidation. Our findings provide new insights into the mechanisms underlying the distinct effects of procaine and GH3 on DNA damage.

Products Derived from Buchenavia tetraphylla Leaves Have In Vitro Antioxidant Activity and Protect Tenebrio molitor Larvae against Escherichia coli-Induced Injury.

The relevance of oxidative stress in the pathogenesis of several diseases (including inflammatory disorders) has traditionally led to the search for new sources of antioxidant compounds. In this work, we report the selection of fractions with high antioxidant action from B. tetraphylla (BT) leaf extracts. In vitro methods (DPPH and ABTS assays; determination of phenolic and flavonoid contents) were used to select products derived from B. tetraphylla with high antioxidant action. Then, the samples with the highest potentials were evaluated in a model of injury based on the inoculation of a lethal dose of heat-inactivated Escherichia coli in Tenebrio molitor larvae. Due to its higher antioxidant properties, the methanolic extract (BTME) was chosen to be fractionated using Sephadex LH-20 column-based chromatography. Two fractions from BTME (BTFC and BTFD) were the most active fractions. Pre-treatment with these fractions protected larvae of T. molitor from the stress induced by inoculation of heat-inactivated E. coli. Similarly, BTFC and BTFD increased the lifespan of larvae infected with a lethal dose of enteroaggregative E. coli 042. NMR data indicated the presence of aliphatic compounds (terpenes, fatty acids, carbohydrates) and aromatic compounds (phenolic compounds). These findings suggested that products derived from B. tetraphylla leaves are promising candidates for the development of antioxidant and anti-infective agents able to treat oxidative-related dysfunctions.

INFLUÊNCIAS DOS MÉTODOS DE COCÇÃO NA PRESERVAÇÃO DE COMPOSTOS BIOATIVOS NA BETA VULGARIS, L.

Introdução: Vive-se em uma época em que o papel dos alimentos na manutenção da vida e da saúde no cotidiano, vem sendo cada vez mais estudados, pelos benefícios por eles concebidos. Por este motivo os compostos bioativos vem sendo cada vez mais utilizados, um deles é a betalaina. Este composto está presente na Beta vulgaris, L. (beterraba), cogumelos, e algumas flores. Assim como vários outros compostos fenólicos, antocianinas, carotenoides, e o seu estudo em relação a saúde do consumidor. Como a beterraba é uma hortaliça complexa nestes componentes, e muito consumida em diferentes formas culinárias. Objetivo: Avaliar os métodos de cocção em airfyrer, micro-ondas e cozimento convencional em panela. Metodologia: Assim, verificando a influência de diferentes métodos de cocção, quanto ao tempo de preparo, alterações em fator antioxidante, compostos fenólicos, e a preferência de cada cocção, a qual por teste de preferência foi definida o melhor consumo, Resultados: assim sobressaindo as provenientes da preparação em micro-ondas e panela. E por análises de compostos fenólicos, a maior concentração em preparações que passam por tratamento térmico. Mas em contrapartida, uma maior ação antioxidante na beterraba in natura, demonstrando a susceptibilidade em seus compostos em alterar diante ao meio exposto. Conclusão: Sendo de grande importância o seu consumo em variadas formas de cocção em preparações gastronômicas para um aproveitamento de todos os seus compostos nela expressa.

Syntesis and characterization of zein nanoparticles loaded with essential oil of Ocimum gratissimum and Pimenta racemosa

Essential oils are extremely volatile and chemically unstable when submitted to a processing, and new strategies are necessary to stabilize them, prolonging and preserving their characteristics. In present research, essential oils of Ocimum gratissimum and Pimenta racemosa were analyzed by CG/MS. Zein nanoparticles loaded with Ocimum gratissimum and Pimenta racemosa were syntetized and their physichochemical characteristics, antioxidant activity, encapsulation efficiency and stability during storage were evaluated. The results of FT-IR prove a positive encapsulation. Micrographs obtained by TEM demonstrate that nanoparticles presented homogeneous populations, spherical shape, smooth surface. Nanoparticles loaded with essential oils presented a good physicochemical stability, with a high encapsulation efficiency, without formation of precipitant during the 180 days of storage on 6 and 20 °C. Moreover, nanoparticles presented capacity to reduce the free radical DPPH, demonstranting antioxidant activity. Thus, zein nanoparticles loaded with essential oil of Ocimum gratissimum and Pimenta racemosa presents a potential to application in a food system, with a good stability and high antioxidant action.

English

Amburana cearensis is a medicinal plant widely used in folk medicine. The purpose of this study was to identify the more appropriate extraction solvent for maximum antioxidant and antimicrobial effect. The extraction of A. cearensis seeds were carried out gradually to obtain the highest yields and constituents of the extracts using as solvent hexane, methanol, 80% alcohol and water in this sequence. Phytochemical screening showed phenolic compounds and thin layer chromatography (TLC) showed the flavonoid morin. Antioxidant activity was also evaluated by the method of scavenging the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH); rutin and ascorbic acid was used as standard; the hydro-alcoholic extract (EEA) showed an IC50 value of 17.95 μg/ml, similarly to the standards rutin and ascorbic acid, indicating high antioxidant action. The microdilution assay (MIC) showed antibacterial activity against the bacteria concentrations, values ≥0.25 mg/mL for EEA and aqueous (AEA) extracts against S. aureus, P. aeruginosa and S. flexneri. High performance liquid chromatography (HPLC) analysis of A. cearenses seed extracts revealed a high content of flavonoids and tannin compounds corroborating with TLC analysis. The extraction by exhaustion was very effective in exposing the bioactive principles of A. cearenses seeds showing their best compounds mainly in EEA extract.   Key words: Amburana cearensis, exhaustion extraction, seed, phytochemical profile, antioxidant, antimicrobial activity.

High Antioxidant Action and Prebiotic Activity of Hydrolyzed Spent Coffee Grounds (HSCG) in a Simulated Digestion-Fermentation Model: Toward the Development of a Novel Food Supplement.

Spent coffee grounds are a byproduct with a large production all over the world. The aim of this study was to explore the effects of a simulated digestion-fermentation treatment on hydrolyzed spent coffee grounds (HSCG) and to investigate the antioxidant properties of the digestion and fermentation products in the human hepatocellular carcinoma HepG2 cell line. The potentially bioaccessible (soluble) fractions exhibited high chemoprotective activity in HepG2 cells against oxidative stress. Structural analysis of both the indigestible (insoluble) and soluble material revealed partial hydrolysis and release of the lignin components in the potentially bioaccessible fraction following simulated digestion-fermentation. A high prebiotic activity as determined from the increase in Lactobacillus spp. and Bifidobacterium spp. and the production of short-chain fatty acids (SCFAs) following microbial fermentation of HSCG was also observed. These results pave the way toward the use of HSCG as a food supplement.

Synthesis and evaluation of the antioxidant activity of {[1-aryl-4-chloro-1H-imidazole-5-YL) methyl]thio}alkane carboxylic acids

This study is devoted to development of the optimal conditions for synthesis and the study of some “structure – antioxidant activity” regularities of [(1-arylimidazole-5-yl)methylthio]alkane carboxylic acids, which structural analogues have found an application as medicinal products with a wide range of biological activities. The methodology of interaction between 4-cloro-5-chloromethylimidazoles with thioglycolic and thiopropionic acids has been used to obtain these compounds. Selection of the optimal reaction conditions has allowed to obtain target compounds in a dry dimethylformamide in the presence of potash at 50°C with yields of 75-82%. The compounds synthesized are high-melting crystalline substances that dissolve well in polar organic solvents and aqueous alkaline solutions. Their composition and structure have been confirmed by the results of elemental analysis and measurement data of IR-, 1H NMR- and chromatography mass-spectra. The study of the compounds synthesized has been conducted in vitro on biological samples. The antioxidant activity has been determined by the inhibition value of the ascorbate-dependent endogenous lipid peroxidation rate in rats’ liver found by the concentration of one of the products of free-radical lipid oxidation processes – malonaldehyde in the test sample. The results of the biological activity screening of the compounds synthesized show that all imidazole derivatives studied in the final concentration ranges of 10-3-10-1 M exhibit a high antioxidant action in the system in vitro. It has been found that the value of the antioxidant activity is influenced by the nature and position of the substituent in position 1 of imidazole. In particular, the presence of electron-acceptor substituents in the aryl fragment decreases the molecule activity in comparison with electron-donor substituents, wherein increase of the methylene groups quantity in the carboxyalkylthiol fragment does not significantly impact the antioxidant effect of the compounds.

Antioxidant capacities, phenolic profile and cytotoxic effects of saxicolous lichens from trans-Himalayan cold desert of Ladakh.

Fourteen saxicolous lichens from trans-Himalayan Ladakh region were identified by morpho-anatomical and chemical characteristics. The n-hexane, methanol and water extracts of the lichens were evaluated for their antioxidant capacities. The lichen extracts showing high antioxidant capacities and rich phenolic content were further investigated to determine their cytotoxic activity on human HepG2 and RKO carcinoma cell lines. The ferric reducing antioxidant power (FRAP), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH) and nitric oxide (NO) radical scavenging capacities and β-carotene-linoleic acid bleaching property exhibited analogous results where the lichen extracts showed high antioxidant action. The lichen extracts were also found to possess good amount of total proanthocyanidin, flavonoid and polyphenol. The methanolic extract of Lobothallia alphoplaca exhibited highest FRAP value. Methanolic extract of Xanthoparmelia stenophylla showed the highest ABTS radical scavenging capacity. The n-hexane extract of Rhizoplaca chrysoleuca exhibited highest DPPH radical scavenging capacity. Highest antioxidant capacity in terms of β-carotene linoleic acid bleaching property was observed in the water extract of Xanthoria elegans. Similarly, Melanelia disjuncta water extract showed highest NO scavenging capacity. Among n-hexane, methanol and water extracts of all lichens, the methanolic extract of Xanthoparmelia mexicana showed highest total proanthocyanidin, flavonoid and polyphenol content. From cytotoxic assay, it was observed that the methanolic extracts of L. alphoplaca and M. disjuncta were exhibiting high cytotoxic effects against cancer cell growth. Similarly, the water extract of Dermatocarpon vellereum, Umbilicaria vellea, X. elegans and M. disjuncta and the methanolic extract of M. disjuncta and X. stenophylla were found to possess high antioxidant capacities and were non-toxic and may be used as natural antioxidants for stress related problems. Our studies go on to prove that the unique trans-Himalayan lichens are a hitherto untapped bioresource with immense potential for discovery of new chemical entities, and this biodiversity needs to be tapped sustainably.

Chemical composition and antioxidant capacities of phytococktail extracts from trans-Himalayan cold desert.

BackgroundHimalayan plants are widely used in traditional system of medicine both as prophylactics and therapeutics for high altitude maladies. Our aim was to evaluate the antioxidant capacities and bioactive compounds of methanol and n-hexane extracts of the phytococktail comprising of sea buckthorn (Hippophae rhamnoides), apricot (Prunus armeniaca) and roseroot (Rhodiola imbricata) from trans-Himalaya.MethodsThe 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and nitric oxide (NO) radical scavenging capacities and lipid peroxidation inhibition (LPI) property of the extracts were determined. Total antioxidant power was determined by ferric reducing/antioxidant power (FRAP) assay. Total polyphenol, flavonoid, flavonol, proanthocyanidin and carotenoid were also estimated for both extracts. We have identified and quantified the phyto-chemotypes present in the methanol and n-hexane extracts by hyphenated gas chromatography/mass spectrometry (GC/MS) technique.ResultsAntioxidant capacity assays using DPPH, ABTS, NO, LPI and FRAP exhibited analogous results where the phytococktail showed high antioxidant action. The phytococktail was also found to possess high quantity of total polyphenol, flavonoid, flavonol and carotenoid. A significant and linear correlation was found between the antioxidant capacities and bioactive principles. A total of 32 phyto-chemotypes were identified from these extracts by GC/MS chemometric fingerprinting. Major phyto-chemotypes identified by GC/MS were glycosides, phenylpropanoids and derivatives, terpenoids, alkaloids, phytosterols, fatty acids and esters, alkaloids and derivatives, organic acid esters and aromatic ethers with positive biological and pharmacological actions.ConclusionThe phytococktail extracts were found to contain considerable amount of diverse bioactive compounds with high antioxidant capacities. The presence of hydrophilic and lipophilic antioxidants in the phytococktail could have contributed to the higher antioxidant values. Hence, the phytococktail could be used as natural source of antioxidants to ameliorate disorders associated with oxidative stress.

Structural features and bioavailability of four flavonoids and their implications for lifespan-extending and antioxidant actions in C. elegans

Various studies have demonstrated longevity effects of flavonoids, a major sub-group of plant polyphenolic compounds, in Caenorhabditis elegans. To better understand their structure–activity relationship in vivo we have used a comparative approach by exposing C. elegans to the structurally related flavonoids myricetin, quercetin, kaempferol and naringenin, and assessed their impact on lifespan and on putative modes of action. The bioavailability of the tested flavonoids was demonstrated by high-performance liquid chromatography with diode-array detection (HPLC/DAD) and a 2-aminoethyl diphenyl borate-based in vivo approach. While all flavonols increased lifespan in wild-type, only myricetin elongated the mev-1(kn1) lifespan, suggesting that the flavonols antioxidant action alone is not sufficient for longevity. Structural prerequisites of high antioxidant action in vitro were also essential to reduce the reactive oxygen species (ROS) load in vivo in C. elegans and were tested in isolated mouse muscle mitochondria. Since the insulin/IGF-like signaling (IIS) cascade is a key regulator of lifespan, all compounds were tested for the ability to cause nuclear translocation of the FOXO transcription factor DAF-16 and changes in target gene expression. An increased DAF-16 translocation and sod-3 promoter activity were observed with all flavonoids but was independent of their ROS scavenging capability and their effects on lifespan.