Influence of hydrocolloids (galactomannan and xanthan gum) on the physicochemical and sensory characteristics of gluten-free cakes based on fava beans (Phaseolus lunatus).

Most gluten-free bakery formulations have starch sources of low nutritional value. The objective of this work was to use fava beans (Phaseolus lunatus) for the production of gluten-free sponge cakes, in addition to evaluating the effects of the partial substitution of fava bean flour by galactomannan and xanthan gum, isolated or mixed at 0.5 and 1.0% proportions, compared with a commercial reference. The properties such as viscosity, specific gravity and microscopy of the air bubbles were evaluated in the raw cakes, while the cooked cakes were analyzed according to physicochemical (chemical composition, specific volume, texture and color) and sensorial properties. Hydrocolloids increased the viscosity, specific gravity, and incorporation of air into the batters. Xanthan gum increased the cakes' firmness after cooking; in what concerns color parameters, hydrocolloids did not interfere. Cakes based on fava beans had better sensory acceptance with or without the presence of hydrocolloids and presented higher levels of moisture, proteins, lipids and ashes when compared to the commercial reference, proving to be an excellent food option without gluten and high nutritional value.

Biological Activities of Libidibia (Caesalpinia) ferrea var. parvifolia (Mart. ex Tul.) L. P. Queiroz Pod Preparations.

Libidibia ferrea has been used in folk medicine throughout Brazil, and this study evaluated the biological activities of crude extract (CE) as well as a partially purified fraction (F80) obtained from its pods. Results from the MTT assay revealed that only F80 inhibited NCI-H292 cell growth; however, neither CE nor F80 reduced HEp-2 cell growth or sarcoma 180 tumor weight with the in vivo assay. Acute oral toxicity of the extract and fraction was evaluated following the steps of Guideline 423, using female mice; LD(50) for both preparations was determined as 2,500 mg/kg body weight. CE and F80 promoted a reduction of the leukocyte number and nitrite level in inflammatory exudates when the anti-inflammatory assay (carrageenan-induced peritonitis) was performed. CE and F80 inhibited writhing regarding antinociceptive activity (acetic acid-induced writhing response in mice). In conclusion, CE and F80 have no significant cytotoxic or antitumor activities in cell lines showing low toxicity and no action against tumors in vivo. Both preparations revealed anti-inflammatory and antinociceptive activities, corroborating the pharmacological basis of L. ferrea for ethnomedical use.

A novel antimicrobial lectin from Eugenia malaccensis that stimulates cutaneous healing in mice model.

OBJECTIVE: The present work reports the purification and partial characterization of an antibacterial lectin (EmaL) obtained from Eugenia malaccensis seeds as well as the evaluation of its effect in the daily topical treatment of repairing process of cutaneous wounds in mice. MATERIALS AND METHODS: The cutaneous wound was produced by the incision of the skin and use of lectin in the treatment of mice cutaneous wounds was evaluated. Surgical wounds were treated daily with a topical administration of EmaL and parameters such as edema, hyperemia, scab, granulation and scar tissues as well as contraction of wounds were analyzed. RESULTS: A novel lectin, with a molecular mass of 14 kDa, was isolated from E. malaccensis using affinity chromatography. The lectin (EmaL) agglutinated glutaraldehyde-treated rabbit and human erythrocytes; the lectin-induced rabbit erythrocyte agglutination was inhibited by glucose, casein, ovalbumin and fetuin. Also, Emal was very effective in the inhibition of bacterial growth, with the best inhibition results obtained for Staphylococcus aureus. Inflammatory signals such as edema and hyperemia were statistically less intense when EmaL was applied compared to the control. The histopathological analysis showed that the treated injured tissue presented reepithelialization (complete or partial) and areas of transition more evidenced than those of the control group, especially due to well organized pattern of collagen fibers presented in the granulation fibrous tissue. CONCLUSION: Presented results are a preliminary indication of the pharmacological interest in using EmaL as antimicrobial agent and in the repairing process of cutaneous wounds.

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.

Purification of a lectin from Eugenia uniflora L. seeds and its potential antibacterial activity.

AIMS: The aim of this work was to analyse the antimicrobial properties of a purified lectin from Eugenia uniflora L. seeds. METHODS AND RESULTS: The E. uniflora lectin (EuniSL) was isolated from the seed extract and purified by ion-exchange chromatography in DEAE-Sephadex with a purification factor of 11.68. The purified lectin showed a single band on denaturing electrophoresis, with a molecular mass of 67 kDa. EuniSL agglutinated rabbit and human erythrocytes with a higher specificity for rabbit erythrocytes. The haemagglutination was not inhibited by the tested carbohydrates but glycoproteins exerted a strong inhibitory action. The lectin proved to be thermo resistant with the highest stability at pH 6.5 and divalent ions did not affect its activity. EuniSL demonstrated a remarkable nonselective antibacterial activity. EuniSL strongly inhibited the growth of Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella sp. with a minimum inhibitory concentration (MIC) of 1.5 microg ml(-1), and moderately inhibited the growth of Bacillus subtilis, Streptococcus sp. and Escherichia coli with a MIC of 16.5 microg ml(-1). CONCLUSIONS: EuniSL was found to be effective against bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: The strong antibacterial activity of the studied lectin indicates a high potential for clinical microbiology and therapeutic applications.

Chitosan from Syncephalastrum racemosum used as a film support for lipase immobilization.

Chitosan from a native Mucoralean strain, Syncephalastrum racemosum, isolated from herbivorous dung (Northeast-Brazil), was used as a film support for lipase immobilization. S. racemosum showed highest chitosan yield (152 mg g dry mycelia weight(-1); 15.2% of dry mycelia weight) among the nine strains screened, which presented 89% D-glucosamine. A chitosan film was used for lipase (EC 3.1.1.3) immobilization using glutaraldehyde as a bifunctional agent. The immobilized lipase retained 47% (12.6 micromol s(-1) m(-2)) of its initial catalytic activity after four cycles of reaction. This result is comparable (same order of magnitude) to that of the enzyme immobilized on film made from commercially available crustacean chitosan.