Copaiba (Copaifera duckei Dwyer, Fabaceae) oleoresin is an important Amazonian raw material. Despite its insecticidal potential, poor water solubility remains a challenge for the development of effective and viable products. Nanotechnology has emerged as a promising area to solve this problem, especially oil-in-water nanoemulsions. On this context, the aim of the present study was to develop oil-in-water nanoemulsions using copaiba oleoresin dispersed through a high internal phase; and evaluate its potential insecticidal action against Aedes aegypti larvae. Overall, 31 formulations were prepared, ranging from 11.5 ± 0.2 to 257.3 ± 4.1nm after one day of manipulation. Some of them reached small mean droplet sizes (< 200nm) and allowed achievement of a nanoemulsion region. The formulation consisted of 5% (w/w) of copaiba oil, 5% (w/w) of surfactant and 90% (w/w) of water, which presented mean droplet size of 145.2 ±0.9nm and polidispersity of 0.378 ± 0.009 after one day of manipulation, and these were evaluated for larvicidal potential. According to mortality level (250ppm - 93.3 after 48h), this nanoemulsion was classified as a promising insecticidal agent against Aedes aegypti larvae. The present study allowed the development of low-cost ecofriendly green natural-based nanoformulations with potential larvicidal activity, using a nanobiotechnology approach

The purpose of this study was to use the informations relating to parasite crustaceans species that was published over the course of one century (1913 to 2013), in order to search for infestation and distribution patterns among these ectoparasites in Brazilian freshwater fish species. This search was carried out on 445 samples of 119 host fish of 27 families within the orders Characiformes, Perciformes, Clupeiformes, Mugiliformes, Osteoglossiformes, Symbranchiformes, Tetraodontiformes and Siluriformes from various regions of Brazil. We organized different host-parasite systems into matrices grouping species at different taxonomic and infestation levels and according to host parameters. Five families of parasites (Ergasilidae, Argulidae, Lernaeidae, Lernaeopodidae and Cymothoidae) distributed into 76 species of 27 genera were analyzed in the host samples, which presented dominance of Ergasilidae species, mainly from the genus Ergasilus. Some crustaceans are host and site-specific, especially in relation to fish in particular habitats and lifestyles (e.g. Perulernaea gamitanae, Anphira branchialis and Riggia paranensis), while other parasites frequently have no preference (e.g. Lernaea cyprinacea and Braga patagonica). We found broadly similar distribution patterns for some crustacean species among the different localities, whereas other species showed well-defined geographical patterns, and these findings were discussed.

Evening primrose (Oenothera biennis L., Onagraceae) seeds oil has great economic importance due to its wide industrial application, mainly for medicines and nutraceutics. However, to our knowledge, it remains almost unexplored regarding development of innovative formulations, such as nanoemulsions. On the present study, required Hydroprophile–Lipophile Balance of evening primrose seeds oil was determined (HLB 12) and a stable nanoemulsion (Day 1: mean droplet size: 214.3±0.69nm, polydispersity index: 0.253±0.012. Day 7: mean droplet size: 202.8±0.23nm, polydispersity index: 0.231±0.008) was achieved. Moreover, pseudo-ternary diagram allowed delimitation of nanoemulsion region, contributing to nanobiotechnology of natural products

Preparation of nanoformulations using natural products as bioactive substances is considered very promising for innovative larvicidal agents. On this context, oil in water nanoemulsions develop a main role, since they satisfactorily disperse poor-water soluble substances, such as herbal oils, in aqueous media. Pterodon emarginatus, popularly known as sucupira, has a promising bioactive oleoresin. However, to our knowledge, no previous studies were carried out to evaluate its potential against Culex quinquefasciatus, the main vector of the tropical neglected disease called lymphatic filariasis or elephantiasis. Thus, we aimed to investigate influence of different pairs of surfactants in nanoemulsion formation and investigate if a sucupira oleoresin-based nanoemulsion has promising larvicidal activity against this C. quinquefasciatus. We also evaluated morphological alteration, possible mechanism of insecticidal action and ecotoxicity of the nanoemulsion against a non-target organism. Among the different pairs of surfactants that were tested, nanoemulsions obtained with polysorbate 80/sorbitan monooleate and polysorbate 80/sorbitan trioleate presented smallest mean droplet size just afterwards preparation, respectively 151.0 ± 2.252 and 160.7 ± 1.493 nm. They presented high negative zeta potential values, low polydispersity index (<0.300) and did not present great alteration in mean droplet size and polydispersity index after 1 day of preparation. Overall, nanoemulsion prepared with polysorbate 80/sorbitan monooleate was considered more stable and was chosen for biological assays. It presented low LC50 value against larvae (34.75; 7.31–51.86 mg/L) after 48 h of treatment and some morphological alteration was observed. The nanoemulsion did not inhibit acetylcholinesterase of C. quinquefasciatus larvae. It was not toxic to green algae Chlorella vulgaris at low concentration (25 mg/L). Our results suggest that optimal nanoemulsions may be prepared with different surfactants using a low cost and low energy simple method. Moreover, this prototype proved to be effective against C. quinquefasciatus, being considered an ecofriendly novel nanoproduct that can be useful in integrated control programs of vector control.

This paper characterizes the pattern of ectoparasite and endoparasite communities in an assemblage of 35 sympatric fish from different trophic levels in a tributary from the Amazon River system, northern Brazil. In detritivorous, carnivorous, omnivorous and piscivorous hosts, the species richness consisted of 82 ectoparasites and endoparasites, but protozoan ectoparasites such asIchthyophthirius multifiliis,Piscinoodinium pillulareandTripartiellasp. were dominant species predominated, such that they were present in 80% of the hosts. The taxon richness was in the following order: Monogenea > Nematoda > Digenea > Crustacea > Protozoa > Acanthocephala = Cestoda > Hirudinea. Among the hosts, the highest number of parasitic associations occurred inSatanoperca jurupari,Aequidens tetramerus,Hoplerythrinus unitaeniatus,Hoplosternum littorale,Cichlasoma amazonarum,Chaetobranchus flavescens,Squaliforma emarginata,Chaetobranchopsis orbicularisandHoplias malabaricus. A weak positive correlation between ectoparasite abundance and length of the hosts was observed. Ectoparasite communities of detritivorous, carnivorous and omnivorous hosts were similar, but these differed from the communities of piscivorous hosts. Larval endoparasite species with low host specificity were the main determinants of the parasite infracommunity structure of the fish assemblage. Fish assemblage had few species of helminth that were specialist endoparasites, while many were parasites at the larval stage, infecting intermediate and paratenic hosts. Finally, carnivorous and omnivorous hosts harbored endoparasite communities that were more heterogeneous than those of detritivorous and piscivorous hosts. This result lends supports to the notion that the feeding habits of the host species are a significant factor in determining the endoparasites fauna.