Antioxidant activity of Moringa oleifera tissue extracts

Moringa oleifera is an important source of antioxidants, tools in nutritional biochemistry that could be beneficial for human health; the leaves and flowers are used by the population with great nutritional importance. This work investigates the antioxidant activity of M. oleifera ethanolic (E1) and saline (E2) extracts from flowers (a), inflorescence rachis (b), seeds (c), leaf tissue (d), leaf rachis (e) and fundamental tissues of stem (f). The radical scavenging capacity (RSC) of extracts was determined using dot-blots on thin layer chromatography stained with a 0.4 mm 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) solution; spectrophotometric assays were recorded (515 nm). Antioxidant components were detected in all E1 and E2 from a, b and d. The best RSC was obtained with E1d; the antioxidants present in E2 reacted very slowly with DPPH. The chromatogram revealed by diphenylborinate-2-ethylamine methanolic solution showed that the ethanolic extract from the flowers, inflorescence rachis, fundamental tissue of stem and leaf tissue contained at least three flavonoids; the saline extract from the flowers and leaf tissue revealed at least two flavonoids. In conclusion, M. oleifera ethanolic and saline extracts contain antioxidants that support the use of the plant tissues as food sources.The authors acknowledge financial support from the Portuguese Fundacao para Ciencia e a Tecnologia (FCT) by the Post-doctoral grant SFRH/BPD/37349/2007. The Brazilian Programmes Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) for research grants and fellowships (PMGP and LCBBC) and the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) are acknowledged for financial support

Explorando a versatilidade estrutural das lectinas de plantas para o isolamento e

Simpósio - Lectinas vegetais: purificação e aplicaçõesbiotecnológica

Electronic transference assessment of the redox processes at carbon electrodes coated with Geobacter sulfurreducens that grown at different temperatures

In the present study, the kinetic parameters of redox reactions and the proteomic profiles of Geobacter sulfurreducens grown at different temperatures (25 ºC and 37 ºC) were evaluated. Oxidation peaks with different potentials and current intensities were observed for both cultures. Also, the outer membrane proteins of the bacteria at the two temperatures revealed different profiles that can be responsible for different redox centers. Thus, G. sulfurreducens that grows at different temperatures may express different cytochromes in the external membrane

Influence of the temperature in the electronic transfer mechanism of Geobacter sulfurreducens

Geobacter species are important in the reduction of metals (e.g. Fe, Mn) in soils and sediments and constitute one of the most effective microorganisms known to use electrodes as the sole electron acceptor in microbial fuel cells to generate electricity. G. sulfurreducens transfers electrons directly to the electrode from different external membrane cytochromes. Each cytochrome is associated with a range of electrical potentials, being energetically more favourable than some others. Different growth conditions of the bacteria, such as temperature, may influence the prevalence of certain cytochromes in the external membrane. The aim of this work was to evaluate the difference in the electronic transfer mechanisms in G. sulfurreducens that growth at different temperatures (25 ºC and 37 ºC). The cyclic voltammetry is an electrochemical technique that can be used to assess the redox reactions between bacteria and electrode and was used to compare different cultures of G. sulfurreducens (Figure 1). With these studies it can be concluded that at different temperatures the oxidation peaks potentials and current intensities were different. The current intensity increased in bacteria that growth at higher temperatures but the potential of the oxidation peak was more anodic, thus more energy was required. The oxidation reaction was limited by diffusion. An irreversible electronic transfer is noticed. At 25ºC the kinetic of the reaction had a mixed control and charge transfer was reversible for lower sweep scan rates. SDS-Page was used to characterize the membrane protein complexes. The membrane proteins extracted from bacteria that growth at different temperatures migrated differently in the gel, revealing proteins of different molecular weights. G. sulfurreducens may provide an interesting model for structural comparison of proteins since the two samples revealed different profiles. The separation of the membrane proteins was obtained from sucrose gradient centrifugation and 2D electrophoresis. The complete proteins characterization is already being developed in our laboratories

Coagulant properties of Moringa oleifera protein preparations : application to humic acids removal

This work aimed to characterize the coagulant properties of protein preparations from Moringa oleifera seeds to remove humic acids from water. Three distinct preparations were assayed, namely extract (seeds homogenized with 0.15 M NaCl), fraction (extract precipitated with 60 % w/v ammonium sulphate) and cMoL (protein purified with guar gel column chromatography). The extract showed the highest coagulant activity in a protein concentration between 1 mg/L and 180 mg/L at pH 7.0. The zeta potential of the extract (-10 mV to -15 mV) was less negative than that of the humic acid (-41 mV to -42 mV) in a pH range between 5.0 and 8.0; thus, the mechanism that might be involved in this coagulation activity is adsorption and neutralisation of charges. Reduction of total organic carbon (TOC) and dissolved organic carbon (DOC) was observed in water samples containing 9 mg/L carbon as humic acid when treated with 1 mg/L of the extract. It was also observed a decrease in colour and in the aromatic content of the treated water. These results suggested that the extract from M. oleifera seeds in a low concentration (1 mg/L) can be an interesting natural alternative to remove humic acid from water in developing countries. The dose of extract determined in the present study do not impart odour and colour to the treated water.The authors acknowledge the financial support from the Portuguese Fundacao para Ciencia e a Tecnologia (FCT), through the post-doctoral grant SFRH/BPD/37349/2007, and the Brazilian programmes: Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), VALNATURA ALFA and the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)

Moringa oleifera: Resource management and multiuse life tree

Moringa oleifera Lamarck (Moringaceae family) is a plant native from the Western and sub-Himalayan parts of Northwest India, Pakistan and Afghanistan. This species is widely cultivated across Africa, South-East Asia, Arabia, South America and Caribbean Islands. M. oleifera culture is also being distributed in the Semi-Arid Northeast of Brazil. It is a multiuse life tree with great environmental economic importance in industrial and medical areas. This review reports different purposes of M. oleifera including sustaining environmental resources, soil protection and shelter for animals. This plant requires not much care and distinct parts have bioactive compounds. Moringa tissues used in human and animal diets, also withdraw pollutants from water. The seeds with coagulant properties used in water treatment for human consumption, remove waste products like surfactants, heavy metals and pesticides. The oil extracted from seeds is used in cosmetic production and as biodiesel. M. oleifera tissues also contain proteins with different biological activities, including lectins, chitin-binding proteins, trypsin inhibitors, and proteases. The lectins are reported to act as insecticidal agents against Aedes aegypti (vector of dengue, chikungunya and yellow fevers) and Anagasta kuehniella (pest of stored products) and also showed water coagulant, antibacterial and blood anticoagulant activities. The presence of trypsin inhibitors has been reported in M. oleifera leaves and flowers. The inhibitor from flowers is toxic to larvae of A. aegypti. The flowers also contain caseinolytic proteases that are able to promote clotting of milk. In this sense, M. oleifera is a promising tree from a biotechnological point of view, since it has shown a great variety of uses and it is a source of several compounds with a broad range of biological activities.Conselho Nacional de Desenvolvimento Científico e Tecnológico for fellowship (LCBBC) and to the Foundation for Science and Technology, POPH/FSE (AFSS

Kinetic study of the redox processes in carbon electrodes with Geobacter sulfurreducens at different growth temperatures

Geobacter sulfurreducens is a bacteria that can transfer electrons directly to the electrode from different external membrane cytochromes. Each cytochrome is associated with a range of electrical potentials, being energetically more favourable than some others. Different growth conditions of the bacteria, such as temperature, may influence the prevalence of certain cytochromes in the external membrane. The aim of this work was to evaluate the difference in the kinetic parameters of the electronic transfer in G. sulfurreducens that growth at different temperatures (25 ºC and 37 ºC). The cyclic voltammetry is an electrochemical technique that can be used to assess the redox reactions between bacteria and electrode and was used to compare different cultures of G. sulfurreducens. With these studies it can be concluded that at different temperatures the oxidation peaks potentials and current intensities were different. The current intensity increased in bacteria that growth at higher temperatures but the potential of the oxidation peak was more anodic, thus more energy was required. The oxidation reaction was limited by diffusion. An irreversible electronic transfer is noticed. At 25ºC the kinetic of the reaction had a mixed control and charge transfer was reversible for lower sweep scan rates. SDS-Page was used to characterize the membrane protein complexes. The membrane proteins extracted from bacteria that growth at different temperatures migrated differently in the gel, revealing proteins of different molecular weights. G. sulfurreducens may provide an interesting model for structural comparison of proteins since the two samples revealed different profiles. The separation of the membrane proteins was obtained from sucrose gradient centrifugation and 2D electrophoresis. The complete proteins characterization is already being developed in our laboratories

Isolation of a seed coagulant Moringa oleifera lectin

In this work hemagglutinating activity (HA) was investigated in distinct Moringa oleifera tissue extracts. A new lectin from seeds (cMoL) was purified and characterized; hemagglutinating and coagulating activities were evaluated. HA was detected in 0.15 M NaCl extracts from flowers and rachis inflorescence (5%, w/v), seeds, leaves, fundamental tissue of stem and steam bark (10%, w/v). cMoL isolated after saline extraction and guar gel column chromatography was active at pH range 4.0–9.0 agglutinating erythrocytes from rabbit and human blood types. Extracts of tissues and cMoL activities were carbohydrate inhibited; azocasein and asialofetuin abolished cMoL HA. The lectin was thermostable at 100 °C during 7 h. Polyacrylamide gel electrophoresis under reduced conditions revealed a main polypeptide band of 26.5 kDa; native basic cMoL was detected as a unique band. Seed lectin preparations and cMoL showed coagulant activity, similar to aluminium sulphate, the coagulant most widely used in water treatment.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Ciência e Tecnologia do Estado de Pernambuco (FACEPE)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Científico e Tecnológico (CNPq

Purification, characterization and termiticidal activity of Moringa oleifera flower peptides

Moringa oleifera (Moringaceae) is a tree cultivated in tropical regions . Their flowers are consumed as food, mainly in the Philippines. Antinutritional factors such as lectins and protease inhibitors are common in plant tissues and may disrupt nutrient digestion. This study aimed to isolate and characterize bioactive peptides in M. oleifera flowers. Dried flowers (10 g) were extracted with 0.15 M NaCl (100 mL). A saline extract from M. oleifera flowers (EMo) was treated with 60 and 90% ammonium sulfate. The 60% precipitated fraction (F0-60) was assessed on hemagglutinating, trypsin inhibitor, caseinolytic and endopeptidase activities. The 90% precipitated fraction (F0-90) was submitted to termiticidal activity assay against Nasutitermes corniger (Termitidae), workers and soldiers. None hemagglutinating activity was detected. A M. oleifera flower trypsin inhibitor (MoFTI) was purified on trypsin-Sepharose affinity column and partially characterized. MoFTI activity was stable until 90 °C and lower after heating to 100 ºC (65%). MoFTI was active at pH range 4-8. MoFTI SDS-PAGE showed three polypeptide bands of 14, 22 and 30 kDa. F0-60 showed caseinolytic activity and endopeptidase activity to hydrolyze a-N-benzoyl-DL-arginine-p-nitroanilide. The enzyme adsorbed on ion exchange column, CM-cellulose, was eluted with 1 M NaCl; SDS-PAGE revealed the presence of two polypeptide bands with molecular weights of 14 and 20 kDa. F0-90 promoted mortality of N. corniger workers, but did not affect soldier survival. In conclusion, the M. oleifera flowers contained enzymes, trypsin inhibitor and termiticidal activity.info:eu-repo/semantics/publishedVersio