Publications (2)0 Total impact
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Article: Biological activity of proteins from pulps of tropical fruits
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ABSTRACT: Proteins present in fruit pulps were extracted and concentrated to 90% saturation point with ammonium sulfate. The total protein content (mg/g) from each fruit pulp was: Assai (0.20), Suriname Cherry (0.10), Mangaba (0.62), Yellow Mombim (0.15), Acerola (0.17), Cupuassu (0.54), Melon (0.24) and Passion fruit (0.80). Inhibitory activity against digestive enzymes, bovine trypsin, human salivary α-amylase and porcine pancreatic α-amylase, were assessed. Results show that inhibitory activity against pancreatic α-amylase was greater in yellow mombim and cupuassu pulps with 0.0345 and 0.0335 mg inhibitor/g pulp, respectively. Melon and assai pulps had the greatest inhibitory activity towards salivary α-amylase with 0.042 and 0.142 mg inhibitor/g pulp, respectively. Antitryptic activity was detected in Assai, mangaba, yellow mombim, suriname cherry, acerola and cupuassu. The levels of inhibitory activity were low for most fruits and those with highest activities were assaı́ (0.054 mg/g), mangaba (0.0395 mg/g) and cajá (0.0328 mg/g).Food Chemistry. -
Article: Activity toward Bruchid Pest of a Kunitz-Type Inhibitor from Seeds of the Algaroba Tree (Prosopis juliflora D.C.)
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ABSTRACT: A proteinaceous inhibitor with high activity against papain was found in seeds of the xerophytic algaroba tree (Prosopis julifora). The proteinase inhibitor Pj was purified using Sephacryl S-200 gel filtration followed by reverse-phase high-performance liquid chromatography on a Vidac 18 TP. Inhibitor Pj showed a Mr of 20,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and a Mr of 19.2K by mass spectrometry. The inhibition of papain by the Pj inhibitor was the noncompetitive type, with a Ki value of 0.59 × 10−9 M. The gelatinase activity of papain was strongly inhibited by Pj too. The N-terminal amino acid sequence of the Pj inhibitor showed homology with the N-terminal amino acid sequence of the Kunitz-proteinase inhibitor family. Pj was strongly effective against digestive proteinases from bean weevil Acanthoscelides obtectus and cowpea weevil Callosobruchus maculatus and was moderately active toward midgut proteinases from pod weevil Mimosestes mimosae and Mexican bean weevil Zabrotes subfasciatus. The data shown here suggest that the protein present in algaroba seeds is involved with defense responses to insects and may be an important tool to be used in engineering plants resistant to bean weevils.Pesticide Biochemistry and Physiology.
