Publications by authors named "Maria L Macedo"

Article Synopsis
  • * An aqueous extract of the plant was prepared and tested in rats, revealing that while there were some symptoms indicative of toxicity, the overall lethality was low, with most animals surviving.
  • * The examination of organs post-mortem indicated some necrosis and other changes in dead rats, but overall, the extracted plant showed low toxicity effects on body mass and organ macroscopic evaluation.
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Insect consumption as food is culturally practiced in various regions of the world. In Brazil, there are more than 130 species of edible insects registered, from nine orders, among which stands out the Coleoptera. The larva of the beetle Pachymerus nucleorum Fabricius, 1792, grows into the bocaiuva fruit (Acrocomia aculeata (Jacq.

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Insects have played an important role as human food throughout history, especially in Africa, Asia and Latin America. A good example of edible insects is the mealworm, Tenebrio molitor Linnaeus, 1758 (Coleoptera, Tenebrionidae), which are eaten in Africa, Asia, the Americas and Australia. This species is easily bred in captivity, requiring simple management.

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Over the last few years, a growing number of proteinase inhibitors have been isolated from plants and particularly from seeds and have shown antimicrobial activity. A 20,000 Da serine peptidase inhibitor, named ILTI, was isolated from Inga laurina seeds and showed potent inhibitory enzymatic activity against trypsin. The aim of this study was to determine the effects of ILTI on the growth of pathogenic and non-pathogenic microorganisms.

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Herein described is the biochemical characterisation, including in vitro and in vivo assays, for a proteinase inhibitor purified from Clitoria fairchildiana seeds (CFPI). Purification was performed by hydrophobic interaction and gel filtration chromatography. Kinetic studies of the purified inhibitor showed a competitive-type inhibitory activity against bovine trypsin and chymotrypsin, with an inhibition stoichiometry of 1:1 for both enzymes.

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Entomotoxic plant lectins have been extensively studied in the past two decades, yet the exact mechanisms underlying their toxic effects remain unknown. This study investigated the effects of Dioclea violacea lectin (DVL) on larval development in Anagasta kuehniella. Chronic exposure of larvae (from neonates to the fourth instar) demonstrated that DVL interfered with larval growth, retarding development and decreasing larval mass without affecting survival.

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Article Synopsis
  • The study focuses on the dengue/yellow fever virus transmitted by Aedes aegypti and investigates the effects of the natural proteinase inhibitor, ApTI, on its larvae.
  • ApTI significantly decreased the survival, weight, and digestive enzyme activity in Ae. aegypti larvae, indicating its potential as a control agent against this mosquito species.
  • Additional analyses revealed that ApTI not only caused physical changes in larval gut cells but also that larvae could not adapt to the presence of ApTI, posing challenges for their development.
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This paper describes the characterization of a trypsin inhibitor from Poincianella pyramidalis seeds (PpyTI). The partial sequencing of PpyTI revealed homology to Kunitz inhibitors, clustered as a member of Family I03 in MEROPS database. PpyTI has a single polypeptide chain of 19,042 Da and presents stability at high temperatures (up to 70 °C) and a wide range of pH.

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Resistant bacterial infections are a major health problem in many parts of the world. The major commercial antibiotic classes often fail to combat common bacteria. Although antimicrobial peptides are able to control bacterial infections by interfering with microbial metabolism and physiological processes in several ways, a large number of cases of resistance to antibiotic peptide classes have also been reported.

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Lectins constitute a complex group of proteins found in different organisms. These proteins constitute an important field for research, as their structural diversity and affinity for several carbohydrates makes them suitable for numerous biological applications. This review addresses the classification and insecticidal activities of plant lectins, providing an overview of the applicability of these proteins in crop protection.

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The effects of the beech apricot, Labramia bojeri A. de Candolle (Sapotales: Sapotaceae), seed aqueous extract on the larval development of the velvetbean moth, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), was evaluated. The extract inhibited larval development, pupal weight, and survival and emergence of adults.

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The overwhelming demand for food requires the application of technology on field. An important issue that limits the productivity of crops is related to insect attacks. Hence, several studies have evaluated the application of different compounds to reduce the field losses, especially insecticide compounds from plant sources.

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The Mediterranean flour moth (Anagasta kuehniella) is a pest insect that attacks stored foods. The difficulty in controlling this kind of pest promotes the development of alternatives for pest control, among them the use of proteins with insecticide effect. In this work, we evaluated the role of a trypsin inhibitor purified from Entada acaciifolia seeds (EATI) on the A.

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Plant-derived trypsin inhibitors have been shown to have potent anti-insect effects and are a promising alternative for the biological control of pests. In this work, we tested the anti-insect activity of Adenanthera pavonina trypsin inhibitor (ApTI) against Diatraea saccharalis larvae, a major insect pest in sugarcane. The addition of 0.

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It has been demonstrated that variant vicilins are the main resistance factor of cowpea seeds (Vigna unguiculata) against attack by the cowpea beetle Callosobruchus maculatus. There is evidence that the toxic properties of these storage proteins may be related to their interaction with glycoproteins and other microvillar membrane constituents along the digestive tract of the larvae. New findings have shown that following interaction with the microvilli, the vicilins are absorbed across the intestinal epithelium and thus reach the internal environment of the larvae.

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0The fall armyworm (Spodoptera frugiperda) is an important pest insect due to high degree of polyphagia. In order to better understand its adaptation mechanism against plant protease inhibitors, bioassays were carried supplementing diet with the Kunitz trypsin inhibitor from Entada acaciifolia seeds (EATI). In vitro assays showed an increase of proteolytic activity in EATI-fed larvae midgut.

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Anagasta kuehniella is a polyphagous pest that causes economic losses worldwide. This species produces serine proteases as its major enzymes for protein digestion. In this study, a new serine-protease inhibitor was isolated from Acacia polyphylla seeds (AcKI).

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Insect pests have caused economic losses valued at billions of dollars in agricultural production. Anagasta kuehniella (Zeller), the Mediterranean flour moth, is of major economic importance as a flour and grain feeder and is often a severe pest in flourmills. This study provides a suitable route for the direct preparation of thiosulfonates 2 and 3 from thiols, under mild conditions, with good yields; these thiosulfonates were tested for their regulatory effect on insect growth.

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The objective of this work was to study the insecticidal effect of labramin, a protein that shows lectin-like properties. Labramin was isolated from seeds of the Beach Apricot tree, Labramia bojeri A. DC ex Dubard (Ericales: Sapotaceae), and assessed against the development of the Mediterranean flour moth Ephestia kuehniella Zeller (Lepidoptera: Pyralidae), an important pest of stored products such as corn, wheat, rice, and flour.

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Native Inga laurina (Fabaceae) trypsin inhibitor (ILTI) was tested for anti-insect activity against Diatraea saccharalis and Heliothis virescens larvae. The addition of 0.1% ILTI to the diet of D.

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Talisin is a seed-storage protein from Talisia esculenta that presents lectin-like activities, as well as proteinase-inhibitor properties. The present study aims to provide new in vitro and in silico biochemical information about this protein, shedding some light on its mechanistic inhibitory strategies. A theoretical three-dimensional structure of Talisin bound to trypsin was constructed in order to determine the relative interaction mode.

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The fate of vicilins ingested by Callosobruchus maculatus and the physiological importance of these proteins in larvae and adults have been recently investigated. Vicilins have been demonstrated to be absorbed through the midgut epithelium, circulate in their trimeric form in the haemolymph and are deposited in the fat body. In fat body cells of both sexes, vicilins are partially hydrolyzed and the fragments are eventually deposited in the eggs.

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DMTI-II (23-kDa trypsin inhibitor purified from Dimorphandra mollis seeds) promotes acute inflammation accompanied by an early infiltration of eosinophils, a critical cell type involved in allergic diseases. We have evaluated here the capacity of DMTI-II to enhance the allergic pulmonary inflammation, looking over time to the leukocyte trafficking from bone marrow to peripheral blood, and their recruitment into the allergic airways. Male Wistar rats were sensitized and challenged with ovalbumin (OVA).

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The present paper describes the purification, characterization and determination of the partial primary structure of the first trypsin inhibitor isolated from the family Sapindaceae. A highly stable, potent trypsin inhibitor (SSTI) was purified to homogeneity. SDS-PAGE analysis revealed that the protein consists of a two-polypeptide chain with molecular masses of approximately 15 and 3 kDa.

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Digestive endoprotease activities of the coconut palm weevil, Homalinotus coriaceus (Coleoptera: Curculionidae), were characterized based on the ability of gut extracts to hydrolyze specific synthetic substrates, optimal pH, and hydrolysis sensitivity to protease inhibitors. Trypsin-like proteinases were major enzymes for H. coriaceus, with minor activity by chymotrypsin proteinases.

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