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

Coagulant and antibacterial activities of the water-soluble seed lectin from Moringa oleifera

Aims: The aim of this work was to analyse the coagulant and antibacterial activities of lectin isolated from Moringa oleifera seeds that are used for water treatment. Methods and Results:  The water-soluble M. oleifera lectin (WSMoL) was separated from nonhemagglutinating components (NHC) by chitin chromatography. WSMoL fluorescence spectrum was not altered in the presence of ions that are often present in high concentrations in polluted waters. Seed extract, NHC and WSMoL showed coagulant activity on a turbid water model. Both NHC and WSMoL reduced the growth of Staphylococcus aureus, but only WSMoL caused a reduction in Escherichia coli. WSMoL was also more effective in reducing the growth of ambient lake water bacteria. Conclusions:  Data obtained from this study indicate that WSMoL is a potential natural biocoagulant for water, reducing turbidity, suspended solids and bacteria. Significance and Impact of the Study: Moringa oleifera seeds are a material effective in the treatment of water.The authors express their gratitude to the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) for research grants and fellowship (LCBBC, MLVO and PMGP), the Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco (FACEPE) and the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) for financial support. Authors are grateful to Maria Barbosa Reis da Silva for the technical assistance and to David Pillard and Felix Nonnenmacher for English editing

Lectins : important tools for biocontrol of Fusarium species

Lectins are proteins from non-immune origin, containing two or more binding sites to mono or oligosaccharides. Plant lectins, found in different plant tissues, show a marked heterogeneity with respect to their molecular structure and sugar-binding specificity. Fungi are frequently pathogens of cultivated plant species representing one of the main causes of crop losses. Growth of fungi has been considered a major factor in biodeterioration of materials such as wood, stored grains, paintings, sculptures, leather, and oil. Fusarium is a filamentous fungi genus widely distributed in soil and in association with plants. Fusarium is a pathogen of bananas, corn, rice, wheat, tomatoes, peanuts, among other crops. Some Fusarium species produce mycotoxins that have been found infecting breakfast and infant cereals. Fusarium species can affect human health causing cutaneous infections and keratitis, for example. The intensive use of synthetic fungicides for plant disease control is cause of public concern because of the presence of residues in water and crops for animal and human consumption. Biodegradable fungicides derived from plants have been searched aiming to minimize environmental damage. Antifungal effects on Fusarium species have been reported for lectins isolated from different plant tissues. The role of lectins in fungi plant defense mechanisms may have evolved from its ability to recognize and agglutinate cells or glycoconjugates in sites for potential invasion by infectious agents, with ability to inhibit fungal growth and germination. Antifungal activity has been reported mainly for chitin-binding lectins which are able to bind chitin present in fungal cell wall and interfere in spore germination. In summary, this chapter discusses the optimistic perspectives for lectin preparations that can be applied in agriculture as cheap and biodegradable antifungal agents preventing pollution of the environment without damages to the biodiversity.(undefined

Termiticidal lectins from Myracrodruon urundeuva (Anacardiaceae) cause midgut damage when ingested by Nasutitermes corniger (Isoptera: Termitidae) workers

Myracrodruon urundeuva is a hardwood tree, and its bark, heartwood and leaf contain lectins (MuBL, MuHL and MuLL respectively) with termiticidal activity against Nasutitermes corniger. In this work, the effects of these lectins on the midgut of N. corniger workers were evaluated. The insects were supplied with an artificial diet containing the lectins at their respective LC 50 (previously determined). At 48 h after treatment, the midguts were dissected and fixed for histopathology analyses. Toluidine-blue-stained midguts from lectin-treated workers showed disorganisation, with the presence of debris in the lumen and the absence of brush border. Fluorescence microscopy revealed that the numbers of digestive and proliferating cells were lower in lectin-treated individuals than in the control, and caspase-3 staining confirmed the occurrence of cell apoptosis. Enteroendocrine cells were not seen in the treated individuals. The midguts from treated insects showed greater staining for peroxidase than the control, suggesting that the lectins caused oxidative stress. Staining with wheat germ agglutinin conjugated to FITC revealed that the lectins interfered with the integrity of the peritrophic matrix. This study showed that termiticidal lectins from M. urundeuva cause severe injuries, oxidative stress and cell death in the midgut of N. corniger workers

A Culex quinquefasciatus strain resistant to the binary toxin from Lysinibacillus sphaericus displays altered enzyme activities and energy reserves

Abstract Background The resistance of a Culex quinquefasciatus strain to the binary (Bin) larvicidal toxin from Lysinibacillus sphaericus is due to the lack of expression of the toxin’s receptors, the membrane-bound Cqm1 α-glucosidases. A previous transcriptomic profile of the resistant larvae showed differentially expressed genes coding Cqm1, lipases, proteases and other genes involved in lipid and carbohydrate metabolism. This study aimed to investigate the metabolic features of Bin-resistant individuals by comparing the activity of some enzymes, energy reserves, fertility and fecundity to a susceptible strain. Methods The activity of specific enzymes was recorded in midgut samples from resistant and susceptible larvae. The amount of lipids and reducing sugars was determined for larvae and adults from both strains. Additionally, the fecundity and fertility parameters of these strains under control and stress conditions were examined. Results Enzyme assays showed that the esterase activities in the midgut of resistant larvae were significantly lower than susceptible ones using acetyl-, butyryl- and heptanoyl-methylumbelliferyl esthers as substrates. The α-glucosidase activity was also reduced in resistant larvae using sucrose and a synthetic substrate. No difference in protease activities as trypsins, chymotrypsins and aminopeptidases was detected between resistant and susceptible larvae. In larval and adult stages, the resistant strain showed an altered profile of energy reserves characterized by significantly reduced levels of lipids and a greater amount of reducing sugars. The fertility and fecundity of females were similar for both strains, indicating that those changes in energy reserves did not affect these reproductive parameters. Conclusions Our dataset showed that Bin-resistant insects display differential metabolic features co-selected with the phenotype of resistance that can potentially have effects on mosquito fitness, in particular, due to the reduced lipid accumulation. Graphical Abstrac

Strategies to obtain lectins from distinct sources

Lectins are proteins or glycoproteins that bind specifically to mono, oligo or polysaccharides. They are important biotechnological tools and have been isolated from microorganisms, higher fungus, lichens, plants and animals. Different purification strategies are used to obtain pure lectins. It is important to approach the principles of each method to be used in protein purification before start to work in this important field. The initial purification step is the protein extraction followed by saline fractionation and dialysis. Hemagglutinating activity (HA) is the assay to follow each protocol step. The prepared sample is submitted to chromatographic methods, such as, affinity, ion exchange and molecular exclusion chromatographies to purify the lectins. High resolution techniques for instance the fast protein liquid chromatography (FPLC) and high pressure liquid chromatography (HPLC) are also used to obtain lectins with high purity. A large number of lectins characterized by specific techniques are available with different carbohydrate specificities. Lectins or lectin molecular forms have structural characteristics making them unique proteins. The pure molecules can contribute to unravel its structure, potential biological function, as well as biotechnological and biomedical uses. Lectins can have applications in different areas of knowledge; they can be used to explore cell surface, be applied as mitogenic, cytotoxic and antimicrobial agents, and also be used as antiproliferative molecules for cancer cells. These proteins may be useful in water treatment due to their coagulant and antibacterial properties. Insecticidal lectins with potential biotechnological application for control of agricultural pests have also been described. There are pitfalls in lectin purification; among them is the structural similarity between contaminant proteins or other lectin molecular forms promoting difficulties to the purification process. A common problem is to establish the ideal protocol that ensures high level of purity and good recovery in few steps