ABSTRACT. Since the composition of honey varies with the species of bee as well as flowering and geographical aspects, this study aimed to evaluate the physicochemical and bioactive properties of Apisand stingless bees’honey from the Brazilian Caatinga. Samples of different species of Apis mellifera L.Meliponini (Melipona subnitida, Frieseomellita varia, Melipona mandacaia, Plebeia sp.) and Apis mellifera L.werecollected from honey producersin the state of Rio Grande do Norte. Honey from A. mellifera and stingless bees showed physicochemical differences in some parameters, especially in moisture, free acidity, HMF, water activity, sugars and electric conductivity. There were no differences in color between honeys from A. mellifera and stingless bees. Honeys fromPlebeia sp., F. varia and A. mellifera showed higher antioxidant capacity followed by honeys fromM. mandacaia and M. subnitida. Flavonoids had little influence on the differentiation of antioxidant activities of stingless bees, while the opposite occurred with the phenolic content, where honeys with the highest levels of phenolic also showed higher antioxidant capacity. ABSTRACT aspects beeshoney Caatinga LMeliponini L Meliponini subnitida sp. sp Lwerecollected werecollected Norte A parameters moisture acidity HMF activity conductivity F fromM M content

RESUMO Filmes biopoliméricos podem substituir vantajosamente polímeros de origem petroquímica em diversas áreas, como a de embalagem de frutas e hortaliças. Como esses produtos apresentam respiração e transpiração mesmo após a colheita, as propriedades de barreira e de resistência à água do material são cruciais para o cumprimento de seu propósito. Neste trabalho foram obtidos filmes biopoliméricos baseados em fécula de mandioca (0-3%), quitosana (0-3%), cera de carnaúba (0; 0,2%) e glicerol (0,6%) e suas propriedades de interesse foram determinadas. A incorporação da cera reduziu em média 20% a taxa de permeabilidade ao vapor d’água (TPVA), em relação aos filmes sem cera. Dentre os filmes contendo cera, 1c (3% de fécula) e 2c (2% de fécula e 1% de quitosana) apresentaram valores mais baixos de TPVA, 12,55 g/m²h e 12,42 g/m²h respectivamente, sendo então submetidos a outras caracterizações que revelaram que a substituição parcial da fécula pela quitosana não afetou a espessura dos filmes, causou decréscimo de 14% em sua solubilidade e melhorou suas propriedades mecânicas, o que significa aumento em seu potencial para a aplicação pretendida.

ABSTRACT Biopolymer films can advantageously substitute polymers of petrochemical origin in several areas, such as packaging of fruits and vegetables. As these products exhibit breathability and perspiration even after harvesting, barrier properties and water resistance of the packaging material are crucial. In this work, biopolymer films based on cassava starch (0-3%), chitosan (0-3%), carnauba wax (0; 0.2%) and glycerol (0,6%) were obtained and their properties of interest were determined. The wax incorporation reduced on average 20% of the water vapor transmission rate, WVTR, in relation to the films without wax. Among the films containing wax, 1c (3% starch) and 2c (2% starch; 1% chitosan) presented lower values of WVTR, 12.55 g / m²h and 12.42 g / m²h respectively, were then subjected to other characterizations that revealed that the partial replacement of starch by chitosan did not affect the film thickness, caused a decrease of 14% in its solubility and improved mechanical properties, which means increase in its potential for the intended application.

Biopolymer films have several industrial applications because they are environmentally sustainable. Cassava starch is a biopolymer that is easily available, but has limitations: it is hydrophilic, poorly resistant and degradable. The improvement of these properties was proposed in this research from the use of bentonite clay (BT) as a filling material. The compatibilization of this in the polymer matrix was obtained by ion exchange with an organic anionic surfactant. The formation of intercalated or exfoliated starch nanocomposites in the presence of natural or modified clay was characterized by XRD, FTIR, AFM and SEM. The improvement of water vapor, thermal and mechanical properties was investigated by WVP, solubility, TGA and tensile test. The starch nanocomposites in the presence of modified clay showed a better result than those of natural clay. There was no significant difference in the color of the starch film in the presence of the natural or modified clay.