Denilson de Jesus Assis

Properties and Antioxidant Action of Actives Cassava Starch Films Incorporated with Green Tea and Palm Oil Extracts

There is an interest in the development of an antioxidant packaging fully biodegradable to increase the shelf life of food products. An active film from cassava starch bio-based, incorporated with aqueous green tea extract and oil palm colorant was developed packaging. The effects of additives on the film properties were determined by measuring mechanical, barrier and thermal properties using a response surface methodology design experiment. The bio-based films were used to pack butter (maintained for 45 days) under accelerated oxidation conditions. The antioxidant action of the active films was evaluated by analyzing the peroxide index, total carotenoids, and total polyphenol. The same analysis also evaluated unpacked butter, packed in films without additives and butter packed in LDPE films, as controls. The results suggested that incorporation of the antioxidants extracts tensile strength and water vapor barrier properties (15 times lower) compared to control without additives. A lower peroxide index (231.57%), which was significantly different from that of the control (p<0.05), was detected in products packed in film formulations containing average concentration of green tea extracts and high concentration of colorant. However, it was found that the high content of polyphenols in green tea extract can be acted as a pro-oxidant agent, which suggests that the use of high concentration should be avoided as additives for films. These results support the applicability of a green tea extract and oil palm carotenoics colorant in starch films totally biodegradable and the use of these materials in active packaging of the fatty products.

Bioconversion from crude glycerin by Xanthomonas campestris 2103: xanthan production and characterization

Abstract - The production and rheological properties of xanthan gum from crude glycerin fermentation, a primary by-product of the biodiesel industry with environmental and health risks, were evaluated. Batch fermentations (28 °C/250 rpm /120 h) were carried out using crude glycerin, 0.01% urea and 0.1% KH 2 PO 4 , (% w/v), and compared to a sucrose control under the same operational conditions, using Xanthomonas campestris strain 2103 isolate from Brazil. Its maximal production by crude glycerin fermentation was 7.23±0.1 g·L -1 at 120 h, with an apparent viscosity of 642.57 mPa·s, (2 % w/v, 25 °C, 25 s -1 ), 70% and 30% higher than from sucrose fermentation, respectively. Its molecular weight varied from 28.2 to 36.2×10 6 Da. The Ostwald-de-Waele model parameters ( K and n) indicated a pseudoplastic behavior at all concentrations (0.5 to 2.0 %, w/v) and temperatures (25-85 °C), while its consistency index indicated promising rheological properties for drilling fluid applications. Therefore, crude glycerin has potential as a cost-effective and alternative substrate for non-food grade xanthan production.

Biosynthesis of xanthan gum from residual glycerin from biodiesel production for drilling fluids

Background Several reports have focused on the value and biological transformation of industrial wastes as an alternative substrate for the production of high value-added components. In this context, it can cite the crude residual glycerin obtained as the primary byproduct of biodiesel production, which has increased exponentially during the last years. As an abundant residue, its disposal into the environment entails several drawbacks and health risks [1]. The bioconversion of this by-product into added-value products by fermentation processes is an important alternative to overcoming this environmental issue. Glycerin is an attractive feedstock for the production of useful chemicals [2], since the cost of the fermentation medium represents, for example, a critical aspect of the commercial production of xanthan, which is the most important microbial polysaccharide with widespread commercial applications (e.g. foodstuffs, pharmaceutical, agricultural products, petroliferous industries) [3], due to its rheological properties and its capacity to produce viscous solutions at low concentrations, together with other characteristics like its pseudoplastic property. This study investigates the effect of glycerin as alternative substrate for xanthan production by Xanthomonas campestris, by evaluating its operational production conditions as well as their physicochemical properties, aiming at its application as drilling fluid.

Influence of nitrogen on growth, biomass composition, production, and properties of polyhydroxyalkanoates (PHAs) by microalgae

This study sought to evaluate influence of nitrogen availability on cell growth, biomass composition, production, and the properties of polyhydroxyalkanoates during cultivation of microalgae Chlorella minutissima, Synechococcus subsalsus, and Spirulina sp. LEB-18. The cellular growth of microalgae reduced with the use of limited nitrogen medium, demonstrating that nitrogen deficiency interferes with the metabolism of microorganisms and the production of biomass. The biochemical composition of microalgae was also altered, which was most notable in the degradation of proteins and chlorophylls and the accumulation of carbonaceous storage molecules such as lipids and polyhydroxyalkanoates. Chlorella minutissima did not produce these polymers even in a nitrogen deficient environment. The largest accumulations of the polyhydroxyalkanoates occurred after a 15 days culture, with a concentration of 16% (dry cell weight) produced by the Synechococcus subsalsus strain and 12% by Spirulina sp. LEB-18. Polyhydroxyalkanoates produced by Synechococcus subsalsus and Spirulina sp. LEB-18 presented different thermal and physical properties, indicating the influence of producing strain on polyhydroxyalkanoates properties. The polymers obtained consisted of long chain monomers with 14 to 18 carbon atoms. This composition is novel, as it has not previously been found in PHAs obtained from Synechococcus subsalsus and Spirulina sp. LEB-18.

Investigation of cellular fatty acid composition of Xanthomonas spp. as chemical markers of productivity and quality of xanthan gum

In this study, we investigated the cellular fatty acid profiles of different Xanthomonas pathovars producing xanthan gum and explored the fatty acid composition to identify chemical markers of xanthan gum productivity and quality. Three Xanthomonas pathovars were studied. The fermentation was conducted for 168 h. Samples from the fermented medium were collected for extraction, quantification, and characterization of xanthan. The unsaturated/saturated (U/S) fatty acid ratio in Xanthomonas cells during fermentation was correlated with production, viscosity, and molecular weight of the gum obtained at each 24 h. The Xanthomonas axonopodis pv manihotis 290 strain showed a higher U/S ratio for major cell fatty acids (C16:1ω7/C16:0) as compared with the other two strains; this high ratio was directly associated with xanthan production. No correlation was observed between cellular fatty acid composition and characteristics of xanthan synthesized. Thus, it was possible to determine a production chemical marker for xanthan gum in Xanthomonas strains.

ESTUDO PROSPECTIVO SOBRE AS PROPRIEDADES TERAPÊUTICAS DO ZINGIBER OFFICINALE (GENGIBRE) COM ÊNFASE NA AÇÃO ANTIMICROBIANA

Registros historicos demonstram que as plantas medicinais eram utilizadas por varios povos, uma dessas o Zingiber officinal tambem conhecido como gengibre, encontrada em florestas tropicais, sendo nativo do sudeste Asiatico. O gengibre e uma especiaria amplamente usada para aliviar sintomas como inflamacao, doencas reumaticas e desconfortos gastrintestinais. Seus extratos e seus principais compostos pungentes, os gingerois, tem mostrado varias atividades biologicas, incluindo efeito como agentes antineoplasicos, antiespasmodicos e antiemeticos, inibidores de enzimas, anti-hemorragicos, antifungicos, protetores de celulas neurais, anti reumaticos, microbicidas, antiinflamatorios e antioxidantes. Para tanto, realizou-se uma prospeccao com o intuito de obter um panorama mundial sobre o mercado tecnologico do gengibre, na qual foi feita uma pesquisa a partir de palavras-chave do tema em estudo com codigos da classificacao internacional na base de dados do European Patent Office (EPO), se atendo em informacoes como os inventores, empresas envolvidas, evolucao anual das patentes depositadas, a origem das tecnologias e distribuicao por paises.