Navegando por Assunto "Bioplastic"

Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Desenvolvimento e caracterização de bioplásticos de fécula de mandioca com extrato alcoólico de Vismia Guianensis
(Universidade Federal do Pará, 2024-08-27) SANTOS, Josiel Ferreira; PASCA, Gabriel Adolfo Cabrera; http://lattes.cnpq.br/5642784995274060; https://orcid.org/0000-0002-9411-0889
This work investigates the incorporation of the alcoholic extract of Vismia Guianensis (EAVG) cassava starch, aiming to improve its bioplastic properties. Cassava starch was dissolved in distilled water at the following concentrations with 0.2%, 0.5% and 1.0% EAVG under controlled temperature at the gelatinization point (~70 °C) and then molded to form bioplastics. The prepared samples were characterized by Attenuated Total Reflectance/Fourier Transform Infrared Spectroscopy (ATR/FTIR), Thermogravimetric and Thermal Differential Analysis (TGA-DTA), X-ray Diffraction (XRD), Scanning Electron Microscopy/Energy Spectroscopy Dispersive (SEM/EDS), Atomic Force Microscopy (AFM) and mechanical assays, providing insights into chemical composition, thermal stability, crystallinity, surface morphology and mechanical properties. These techniques comprehensively characterized cassava starch bioplastics with EAVG addition, highlighting their enhanced mechanical properties. The results demonstrated that EAVG played an effective role as a plasticizer, increasing the flexibility, resistance and stability of the biofilm that has a thickness of 0.8 mm, and supports a traction of 4.19 to 18.43 MPa. This study justifies EAVG as a promising additive for the production of biocompatible and sustainable materials, suitable for numerous applications in biodegradable plastics. EAVG presents a path forward for the advancement of bioplastics with improved mechanical, thermal and functional properties, with a promising future in terms of their contribution to new developments in these areas.
Acesso aberto (Open Access)
Uso do óleo de açaí (Euterpe oleracea) e amido de mandioca (Manihot esculenta) na obtenção de produtos bioativos
(Universidade Federal do Pará, 2023-10-30) OLIVEIRA, Sara Caroline Pacheco de; LAGO, Gleice Vasconcelos Pereira do; http://lattes.cnpq.br/7932392876332323; HTTPS://ORCID.ORG/0000-0002-9702-250X; BRASIL, Davi do Socorro Barros; http://lattes.cnpq.br/0931007460545219; https://orcid.org/0000-0002-1461-7306
Cassava is found in abundance in nature, especially in the State of Pará, from them it is possible to extract starch, rich in amylose and amylopectin, components that help in the production of bioplastics. Furthermore, Pará is the largest producer of açaí, a raw material that is also natural and has antioxidant, phenolic and healing compounds. The oil extracted from açaí has the same characteristics found in the pulp, which makes it an excellent agent for incorporation into products added on polymers. The present study reports the characterization of cassava starch and evaluation of the biological characteristics of açaí oil, for the production of an active bioplastic, with the aim of incorporating the benefits found in the oil. To this end, some tests were carried out using plasticizers such as glycerol, ethylene glycol and sorbitol in the composition, to structure the bioplastic, where glycerol proved to be the most viable option. Cassava starch was dried at three temperatures: 45, 60 and 75°C, for the drying curve, and it wasobserved that starch dried at 45°C had better performance, without significant losses in its structure. The analyzes carried out were relevant to detect the potential of açaí oil on incorporating bioplastic. It is known that the characterization of the oil is essential to ensure its quality. Açaí oil was evaluated for 1H NMR, which was essential for quantifying iodine (67.05 I2/g) and saponification (109.06 mg KOH/g) levels. Furthermore, the oil also presented satisfactory results, with emphasis on the following activities: antioxidant (532.56 µM of Trolox/g), anticancer (with reduced metabolic activity and cell viability for the AGP01, SK19 and VERO lines, with IC50 75 .30; 80.15; 73.05 µg/ml, respectively), in addition to the promising result in anti-inflammatory activity that tested target gene TNF-α (tumor necrosis factor alpha) and detected that the samples analyzed with the oil presented anti-inflammatory effect even after 24 hours of exposure, which confirms its bioactivity. This highlights the gigantic potential of using açaí oil for improvement and application in new products, as it has proven to be a strong ally against infectious and cancerous diseases, with cell recovery capacity. Therefore, the oil was incorporated into a polymeric matrix based on cassava starch, which resulted in bioplastic with a thickness (0.157 mm), PVA (19.39 g.mm.KPa-1.d-1.m- 2), transparency (2.60), and one of the highlights was the colorimetric analysis that was able to detect shades of green in the sample, represented by values of -5.75 (a*) and 10.90 (b*), identifying the presence of chlorophyll from açaí oil. In this way, it was possible to note the relevance of using this oil for inclusion in products that bring benefits to the end consumer, in order to take advantage of the chemical and biological properties that this oil has in its composition, as is the case of bioplastic, which contributes to the pharmaceutical sector for presenting bioactivity, in addition to its possible use in the packaging sector and helping to reduce the use of plastics from petroleum, as it is a 100% biodegradable plastic.