Bioaccessibility of trace elements and Fe and Al endogenic nanoparticles in farmed insects: Pursuing quality sustainable food.

This study investigated the in vitro bioaccessibility of aluminum, copper, iron, manganese, lead, selenium, and zinc in three important species of farmed insects: the yellow mealworm (Tenebrio molitor), the house cricket (Acheta domesticus) and the migratory locust (Locusta migratoria). Results show that all three insect species constitute excellent sources of essential elements (Fe, Cu and Zn) for the human diet, contributing to the recommended dietary allowance, i.e., 10%, 50%, and 92%, respectively. A higher accumulation of Se (≥1.4 mg Se/kg) was observed with increasing exposure concentration in A. domesticus, showing the possibility of using insects as a supplements for this element. The presence of Al and Fe nanoparticles was confirmed in all three species using single particle-inductively coupled plasma-mass spectrometry and transmission electron microscopy. The results also indicate that Fe bioaccessibility declines with increasing Fe-nanoparticle concentration. These findings contribute to increase the nutritional and toxicological insights of farmed insects.

Chitosan Films Obtained from Brachystola magna (Girard) and Its Evaluation on Quality Attributes in Sausages during Storage.

High molecular weight chitosan (≈322 kDa) was obtained from chitin isolated from Brachystola magna (Girard) to produced biodegradable films. Their physicochemical, mechanical and water vapor permeability (WVP) properties were compared against commercial chitosan films with different molecular weights. Brachystola magna chitosan films (CFBM) exhibited similar physicochemical and mechanical characteristics to those of commercial chitosans. The CFBM films presented lower WVP values (10.01 × 10-11 g/m s Pa) than commercial chitosans films (from 16.06 × 10-11 to 64.30 × 10-11 g/m s Pa). Frankfurt-type sausages were covered with chitosan films and stored in refrigerated conditions (4 °C). Their quality attributes (color, weight loss, pH, moisture, texture and lipid oxidation) were evaluated at 0, 5, 10, 15 and 20 days. Sausages covered with CFMB films presented the lowest weight loss (from 1.24% to 2.38%). A higher increase in hardness (from 22.32 N to 30.63 N) was observed in sausages covered with CFMB films. Compared with other films and the control (uncovered sausages), CFMB films delay pH reduction. Moreover, this film presents the lower lipid oxidation level (0.10 malonaldehyde mg/sample kg). Thus, chitosan of B. magna could be a good alternative as packaging material for meat products with high-fat content.

Schistocerca piceifrons piceifrons (Orthoptera: Acrididae) as a Source of Compounds of Biotechnological and Nutritional Interest.

The Central American locust, Schistocerca piceifrons piceifrons (Walker) is a major agricultural pest in Mexico and Central America. Control measures against this pest have generated much environmental damage and substantial financial costs because chemical insecticides are used. Yet various Orthoptera species also appear to be a potential source of nutrients and a source of bioactive metabolites. Here, we studied the presence of secondary metabolites in the adult stage of S. p. piceifrons by applying different colorimetric techniques. Adults were collected from the southern region of Tamaulipas, Mexico, during September-December 2017. These samples were subjected to sequential processes of eviscerating, drying, pulverizing, extracting, and detecting of metabolites. Extractions were carried out in water, 50% ethanol, and absolute ethanol. The presence of phenolic compounds, alkaloids, tannins, saponins, flavonoids, and quantity of antioxidants against the DPPH (2, 2-diphenyl-1-picrylhydrazyl) and ABTS (2, 2'-azino-bis, 3-ethylbenzothiazoline-6-sulfonic acid) radicals were determined and reported. Proximate analysis showed that S. p. piceifrons has a high protein content (80.26%), low fat content (6.21%), and fiber content (12.56%) similar to other Orthoptera species. Chitin and chitosan contents of S. p. piceifrons were 11.88 and 9.11%, respectively; the recovery percentage of chitosan from chitin was 76.71%. Among the Orthoptera, the protein content of this pest is among the highest while its contents of chitin and chitosan are similar to those of other insect species (e.g., Bombix mori Linnaeus [Lepidoptera: Bombycidae]). Our results suggest this pest species is a potential source of bioactive compounds of biotechnological interest for use by pharmaceutical and food industries.

Comparative analysis of rDNA location in five Neotropical gomphocerine grasshopper species.

We report here, for the first time, the chromosome complement, number and location of the nucleolar organizer regions (NORs) revealed by silver staining (AgNO(3)) and fluorescent in situ hybridization (FISH) in five Neotropical gomphocerine species: Rhammatocerus brasiliensis, R. brunneri, R. palustris, R. pictus and Amblytropidia sp. The objective of this study was to summarize available data and propose a model of chromosome evolution in Neotropical gomphocerines. All five species studied showed chromosome numbers consisting of 2n = 23,X0 in males and 2n = 24,XX in females. Amblytropidia sp. was the only species showing a bivalent (M(8)) with megameric behavior during meiosis. The rDNA sites were restricted to autosomal pairs, i.e. the pericentromeric region of the S(9) chromosome, the consensus NOR location in all five species. R. brasiliensis was the only species showing additional NORs on M(4) and M(6) pairs which, likewise the S(9) NOR, were active in all cells analyzed. Comparison of these results with those reported previously in Palearctic gomphocerine species suggests higher resemblance of Neotropical species with the Old World species also possessing 23/24 chromosomes. Evolutionary mechanisms responsible for the observed interspecific variation in NOR location in this group are discussed.

Globalization, binational communities, and imported food risks: results of an outbreak investigation of lead poisoning in Monterey County, California.

OBJECTIVES: Although the burden of lead poisoning has decreased across developed countries, it remains the most prevalent environmental poison worldwide. Our objective was to investigate the sources of an outbreak of lead poisoning in Monterey County, California. METHODS: An investigation in 3 county health department clinics in Monterey County, California, was conducted between 2001 and 2003 to identify risk factors for elevated blood lead levels (> or = 10 microg/dL) among children and pregnant women. RESULTS: The prevalence of elevated blood lead levels was significantly higher in 1 of the 3 clinics (6% among screened children and 13% among prenatal patients). Risk factors included eating imported foods (relative risk [RR]=3.4; 95% confidence interval [CI]=1.2, 9.5) and having originated from the Zimatlan area of Oaxaca, Mexico, compared with other areas of Oaxaca (RR=4.0; 95% CI=1.7, 9.5). Home-prepared dried grasshoppers (chapulines) sent from Oaxaca were found to contain significant amounts of lead. CONCLUSIONS: Consumption of foods imported from Oaxaca was identified as a risk factor for elevated blood lead levels in Monterey County, California. Lead-contaminated imported chapulines were identified as 1 source of lead poisoning, although other sources may also contribute to the observed findings. Food transport between binational communities presents a unique risk for the importation of environmental hazards [corrected]

Effects of double-stranded RNA in Metarhizium anisopliae var. acridum and Paecilomyces fumosoroseus on protease activities, conidia production, and virulence.

Isogenic strains (with and without dsRNA) of the entomogenous fungi Metarhizium anisopliae var. acridum and Paecilomyces fumosoroseus were investigated for correlation between the presence of dsRNA and the production of cuticle-degrading proteases that play an important role in host parasitism, total secreted protein, and conidia production. Similar levels of cuticle-degrading subtilisin-like (Pr1) protease were observed for isogenic strains of M. anisopliae var. acridum after growth in medium supplemented with the cuticle of the grasshopper Rhammatocerus schistocercoides. Similarly, no statistical differences were observed for protease production, detected using the chromogenic substrate azocasein. For P. fumosoroseus isogenic strains, no significant differences in protease activity were observed after growth in the presence of either Euschistus heros or Nezara viridula (Hemiptera: Pentatomidae) cuticle. Similarly, no statistical differences were observed in virulence against E. heros. A comparison of mean conidia production showed a significantly higher production in the dsRNA-free isogenic strains of M. anisopliae var. acridum. Although, for most of the fungal phenotypes analysed, no overt effects were associated with the presence of these dsRNA infections, the reduction in conidia production by the isogenic strains of M. anisopliae var. acridum with dsRNA suggested that it may not be entirely accurate to describe these infections as latent.