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An increase in the incidence of arboviral, microbial and parasitic infections, and to disorders related to oxidative stress has encouraged the development of adjuvant therapies based on natural formulations, such as those involving plant extracts. Thus, to expand the repertoire of the available therapeutic options, this study aimed to describe the versatility of Tephrosia toxicaria (Sw.) (Pers., 1807) extracts for the control of arbovirus vectors, as well as their antioxidant, antileishmanial, and antimicrobial potential. Among the aqueous and hydroethanolic extracts obtained, the hydroethanolic extract from roots (RHA) was identified as the most active larvicide extract demonstrating, respectively, the lowest lethal concentration (mg/mL) for 50%, 90% and 99% of Aedes aegypti (L., 1762) and Aedes albopictus (S., 1894) larvae, observed at 24 h (0.33, 0.84 and 1.80; 0.32, 0.70 and 1.32) and 48 h (0.17, 0.51 and 1.22; 0.26, 0.47 and 0.78) post-exposure. Field assays revealed that RHA (0.84 mg/mL) is a potential oviposition deterrent, reducing egg-laying by approximately 90%. RHA (0.1 mg/mL) also exhibited antioxidant activity for the following tests: total antioxidant capacity (286.86 mg AAE/g), iron (87.16%) and copper (25.64%) chelation, and superoxide scavenging (10%). In the cell culture assays, RHA (0.1 mg/mL) promoted regeneration of metabolic activity (92% cell viability) in cells exposed to oxidative stress. Furthermore, RHA displayed weak antileishmanial activity (IC50 = 3.53 mg/mL) against Leishmania amazonensis and not exhibit antimicrobial activity. The extraction favored the concentration of carbohydrates in RHA, in addition to lectins and protease inhibitors, with molecular masses estimated between 10 and 24 kDa. Cytotoxicity and phytotoxicity analyses of RHA suggested its biosecurity. Thus, RHA is a multivalent extract with insecticide and antioxidant properties at low and safe concentrations. However, others studies on its indirect toxic effects are ongoing to ensure the complete safety of RHA.

The trypsin inhibitor isolated from tamarind seeds (TTI) presents satietogenic and anti-inflammatory effects. In the present study, TTI encapsulation by nanoprecipitation in purified chitosan and whey protein isolate (ECW) was performed to maintain TTI's integrity and protection through the gastrointestinal tract. The interaction between TTI and the encapsulating agents was determined by filtration monitoring the antitrypsin activity. Cytotoxicity was evaluated at different concentrations (0.5, 2.5 and 5.0 mg/mL) in Caco-2 and CCD-18Co cells. Subacute blood toxicity was evaluated in Wistar rats (12.5 mg/kg) for ten days. The particles presented a smooth surface, with 118.00 (17.27) nm of diameter, 0.37 (0.02) of polydispersity index, -38.26 (0.15) mV (neutral pH) of surface charge, and 95.31 (0.31)% of incorporation efficiency. At neutral pH, there was a strong interaction of the encapsulating agents and TTI, and a gradual release of TTI at pH 3.0. Cell viability (> 70%) evaluation, in vivo biochemical and hepatic parameters of Wistar rats showed the absence of toxic effects of the nanoparticles with TTI. The study showed that TTI nanoparticles are potentially safe and represent a promising formulation for the clinical application of TTI and may become an option as a novel ingredient in food.

A trypsin inhibitor isolated from tamarind seed (TTI) has satietogenic effects in animals, increasing the cholecystokinin (CCK) in eutrophy and reducing leptin in obesity. We purified TTI (pTTI), characterised, and observed its effect upon CCK and leptin in obese Wistar rats. By HPLC, and after amplification of resolution, two protein fractions were observed: Fr1 and Fr2, with average mass of [M + 14H]+ = 19,594,690 Da and [M + 13H]+ = 19,578,266 Da, respectively. The protein fractions showed 54 and 53 amino acid residues with the same sequence. pTTI presented resistance to temperature and pH variations; IC50 was 2.7 × 10−10 mol.L−1 and Ki was 2.9 × 10−11 mol.L−1. The 2-DE revealed spots with isoelectric points between pH 5 and 6, and one near pH 8. pTTI action on leptin decrease was confirmed. We conclude that pTTI is a Kunitz trypsin inhibitor with possible biotechnological health-related application.

OBJECTIVES: Seeds are excellent sources of proteinase inhibitors, some of which may have satietogenic and slimming actions. We evaluated the effect of a trypsin inhibitor from Tamarindus indica L. seeds on weight gain, food consumption and cholecystokinin levels in Wistar rats. METHODS: A trypsin inhibitor from Tamarindus was isolated using ammonium sulfate (30-60%) following precipitation with acetone and was further isolated with Trypsin-Sepharose affinity chromatography. Analyses were conducted to assess the in vivo digestibility, food intake, body weight evolution and cholecystokinin levels in Wistar rats. Histological analyses of organs and biochemical analyses of sera were performed. RESULTS: The trypsin inhibitor from Tamarindus reduced food consumption, thereby reducing weight gain. The in vivo true digestibility was not significantly different between the control and Tamarindus trypsin inhibitor-treated groups. The trypsin inhibitor from Tamarindus did not cause alterations in biochemical parameters or liver, stomach, intestine or pancreas histology. Rats treated with the trypsin inhibitor showed significantly elevated cholecystokinin levels compared with animals receiving casein or water. CONCLUSION: The results indicate that the isolated trypsin inhibitor from Tamarindus reduces weight gain by reducing food consumption, an effect that may be mediated by increased cholecystokinin. Thus, the potential use of this trypsin inhibitor in obesity prevention and/or treatment should be evaluated.

The peanut is an oleaginous plant of high nutritional value, a source of protein and a trypsin inhibitor. Trypsin inhibitors are proteins present in the vegetable kingdom, considered anti-nutritional factors for animals. However, there have been several recent reports about their heterologous and beneficial effects on human health. These important effects have been the focus of studies investigating these inhibitors in foods. The aim of the present study was to isolate and determine the estimated molecular mass and specific inhibitory activity, for trypsin in the Japanese peanut, peanut butter, and peanut nougat using the techniques of precipitation with ammonium sulfate and affinity chromatography on trypsin - Sepharose CNBr 4B. The techniques used in this study were efficient for isolating the protein inhibitors with antitryptic specific activity of 694 UI mg-1, 823 UI mg-1 and 108 UI mg-1 for the Japanese peanut, peanut nougat, and peanut butter, respectively. The techniques featured high selectivity of the adsorbent, with consequent efficiency in isolation, given the low amount of dosed proteins and specific antitryptic activity presented by the products studied. The various health-related benefits show the importance of detecting and isolating efficient trypsin inhibitors in foods, taking into account the health claims attributed to the vegetable and its high consumption by humans.

Fruit-bearing food products are controlled by phytosanitary regulatory mechanisms. Among the existing pests of economic interest, Cetatitis capitata (medfly) can be highlighted, which can infest from 250 to 400 vegetable varieties. Vicilins, constitutive proteins of chitin-binding seeds, are potentially candidates to fight this pest. Vicillin-rich fractions of Erythrina veluntina (mulungu), Canavalia ensiformis (pork beans) and Phaseolus vulgaris (common beans), isolated by affinity chromatography on a chitin column, were tested on adults of C. capitata, in laboratory and semi-laboratory bioassays. field. All were able to bind chitin, have acidic characteristics and association with carbohydrates. E. velutina vicilin was the only one to present a high lethality (100 %) in a 15 % diet (w/w). In semi-field it was observed that 10 and 15 % (w/w) of vicilin added to the diet were lethal. For TL50, death of half the population in days were 3.5 (10 %) and 3 (15 %). These results showed that vicilins are potential bioinsecticides in the control of C. capitata.