Simultaneous allergen inactivation and detoxification of castor bean cake by treatment with calcium compounds

Ricinus communis L. is of great economic importance due to the oil extracted from its seeds. Castor oil has been used for pharmaceutical and industrial applications, as a lubricant or coating agent, as a component of plastic products, as a fungicide or in the synthesis of biodiesel fuels. After oil extraction, a castor cake with a large amount of protein is obtained. However, this by-product cannot be used as animal feed due to the presence of toxic (ricin) and allergenic (2S albumin) proteins. Here, we propose two processes for detoxification and allergen inactivation of the castor cake. In addition, we establish a biological test to detect ricin and validate these detoxification processes. In this test, Vero cells were treated with ricin, and cell death was assessed by cell counting and measurement of lactate dehydrogenase activity. The limit of detection of the Vero cell assay was 10 ng/mL using a concentration of 1.6 x 10(5) cells/well. Solid-state fermentation (SSF) and treatment with calcium compounds were used as cake detoxification processes. For SSF, Aspergillus niger was grown using a castor cake as a substrate, and this cake was analyzed after 24, 48, 72, and 96 h of SSF. Ricin was eliminated after 24 h of SSF treatment. The cake was treated with 4 or 8% Ca(OH)2 or CaO, and both the toxicity and the allergenic properties were entirely abolished. A by-product free of toxicity and allergens was obtained.

In vitro and in vivo antitumor activity of crude extracts obtained from Brazilian Chromobacterium sp isolates

Natural products produced by microorganisms have been an important source of new substances and lead compounds for the pharmaceutical industry. Chromobacterium violaceum is a Gram-negative β-proteobacterium, abundant in water and soil in tropical and subtropical regions and it produces violacein, a pigment that has shown great pharmaceutical potential. Crude extracts of five Brazilian isolates of Chromobacterium sp (0.25, 2.5, 25, and 250 µg/mL) were evaluated in an in vitro antitumor activity assay with nine human tumor cells. Secondary metabolic profiles were analyzed by liquid chromatography and electrospray ionization mass spectrometry resulting in the identification of violacein in all extracts, whereas FK228 was detected only in EtCE 308 and EtCE 592 extracts. AcCE and EtCE 310 extracts showed selectivity for NCI/ADR-RES cells in the in vitro assay and were evaluated in vivo in the solid Ehrlich tumor model, resulting in 50.3 and 54.6% growth inhibition, respectively. The crude extracts of Chromobacterium sp isolates showed potential and selective antitumor activities for certain human tumor cells, making them a potential source of lead compounds. Furthermore, the results suggest that other compounds, in addition to violacein, deoxyviolacein and FK228, may be involved in the antitumor effect observed.

Lipid peroxidation, detoxification capacity, and genome damage in mice after transplacental exposure to pharmaceutical drugs

Data on genome damage, lipid peroxidation, and levels of glutathione peroxidase (GPX) in newborns after transplacental exposure to xenobiotics are rare and insufficient for risk assessment. The aim of the current study was to analyze, in an animal model, transplacental genotoxicity, lipid peroxidation, and detoxification disturbances caused by the following drugs commonly prescribed to pregnant women: paracetamol, fluconazole, 5-nitrofurantoin, and sodium valproate. Genome damage in dams and their newborn pups transplacentally exposed to these drugs was investigated using the in vivo micronucleus (MN) assay. The drugs were administered to dams intraperitoneally in three consecutive daily doses between days 12 and 14 of pregnancy. The results were correlated, with detoxification capacity of the newborn pups measured by the levels of GPX in blood and lipid peroxidation in liver measured by malondialdehyde (HPLC-MDA) levels. Sodium valproate and 5-nitrofurantoin significantly increased MN frequency in pregnant dams. A significant increase in the MN frequency of newborn pups was detected for all drugs tested. This paper also provides reference levels of MDA in newborn pups, according to which all drugs tested significantly lowered MDA levels of newborn pups, while blood GPX activity dropped significantly only after exposure to paracetamol. The GPX reduction reflected systemic oxidative stress, which is known to occur with paracetamol treatment. The reduction of MDA in the liver is suggested to be an unspecific metabolic reaction to the drugs that express cytotoxic, in particular hepatotoxic, effects associated with oxidative stress and lipid peroxidation.

Advanced glycation end products (AGEs) and their receptor (RAGE) induce apoptosis of periodontal ligament fibroblasts

Diabetics have an increased prevalence of periodontitis, and diabetes is one of the causative factors of severe periodontitis. Apoptosis is thought to be involved in this pathogenic relationship. The aim of this study was to investigate apoptosis in human periodontal ligament (PDL) fibroblasts induced by advanced glycation end products (AGEs) and their receptor (RAGE). We examined the roles of apoptosis, AGEs, and RAGE during periodontitis in diabetes mellitus using cultured PDL fibroblasts that were treated by AGE-modified bovine serum albumin (AGE-BSA), bovine serum albumin (BSA) alone, or given no treatment (control). Microscopy and real-time quantitative PCR indicated that PDL fibroblasts treated with AGE-BSA were deformed and expressed higher levels of RAGE and caspase 3. Cell viability assays and flow cytometry indicated that AGE-BSA reduced cell viability (69.80±5.50%, P<0.01) and increased apoptosis (11.31±1.73%, P<0.05). Hoechst 33258 staining and terminal-deoxynucleotidyl transferase-mediated nick-end labeling revealed that AGE-BSA significantly increased apoptosis of PDL fibroblasts. The results showed that the changes in PDL fibroblasts induced by AGE-BSA may explain how AGE-RAGE participates in and exacerbates periodontium destruction.

Survey of aflatoxins in tomato products

Tomatoes are highly susceptible to fungi contamination in the field, during transportation, processing, and storage. Aspergillus flavus and Aspergillus parasiticus have been isolated from tomatoes and tomato products, and both fungi species can produce aflatoxin, mycotoxin with hepatotoxic, carcinogenic, teratogenic, and mutagenic effects on all animal species tested so far. In order to verify a possible aflatoxin contamination of tomato products commercialized in Brazil, 63 samples of tomato products (pulp, paste, purée, ketchup, dehydrated tomatoes, and dried tomatoes preserved in oil) produced in 5 Brazilian states and 1 imported sample (ketchup), totalizing 29 brands, were analyzed by thin layer chromatography. The analytical method showed an average recovery of 86% for all aflatoxins at two spiking levels. The limits of detection for the aflatoxins B1, B2, G1, and G2 varied with the type of the product ranging from 2 to 7 µg/kg. Aflatoxins were not detected in any evaluated sample indicating that they did not pose a risk to human health since there was no invasion of raw materials by toxigenic fungi or no conditions for toxin production.

Obtention and characterization of gluten-free baked products

This work had as objective the development of gluten-free breads and muffins using rice flour and maize and cassava starches. From seven samples resulting from a Simplex-Centroid design, the sensory and instrumental analyses of specific volume, elasticity, and firmness were performed. For the sensory analysis, the optimized formulation contained 50% of rice flour and 50% of cassava starch, and for the instrumental evaluation, the optimal simultaneous point for the three conducted analyses were 20% of rice flour, 30% of cassava starch, and 50% of maize starch. A comparative analysis of specific volume, elasticity, firmness, and triangular test was performed with pre-baked, baked, and frozen bread. Physicochemical, nutritional, and microbiological analyses were performed for both bread and muffin according to the Brazilian legislation.

Application of Response Surface Methodology to study the effect of different calcium sources in fish muscle-alginate restructured products

Sodium alginate needs the presence of calcium ions to gelify. For this reason, the contribution of the calcium source in a fish muscle mince added by sodium alginate, makes gelification possible, resulting a restructured fish product. The three different calcium sources considered were: Calcium Chloride (CC); Calcium Caseinate (CCa); and Calcium lactate (CLa). Several physical properties were analyzed, including mechanical properties, colour and cooking loss. Response Surface Methodology (RSM) was used to determine the contribution of different calcium sources to a restructured fish muscle. The calcium source that modifies the system the most is CC. A combination of CC and sodium alginate weakened mechanical properties as reflected in the negative linear contribution of sodium alginate. Moreover, CC by itself increased lightness and cooking loss. The mechanical properties of restructured fish muscle elaborated were enhanced by using CCa and sodium alginate, as reflected in the negative linear contribution of sodium alginate. Also, CCa increased cooking loss. The role of CLa combined with sodium alginate was not so pronounced in the system discussed here.

Culture alternative medium for the growth of extreme halophilic bacteria in fish products

Halotolerant or halophilic (Archaeabacteria) microorganisms can be found in salted and ripening fish products that are not affected by salt. They can be moderate or extremely halophilic bacteria. The extremely halophilic bacteria require between 15-30% of NaCl for growth. The extremely halophilic archaeobacteria may be selectively isolated in different media. The aim of this work was to determine the effectiveness of the Salt-Agar-Milk medium, a medium modified in our laboratory through the addition of MgSO4 and KCl - named SAMm, and its effect on the bacterial growth by means of comparison with other media, with and without milk, determining time of incubation and counting. Two samples of salted fish from local fish salting factories and two laboratory strains were used. The factory samples were matured anchovy and anchovy fillets in oil, and the laboratory strains were: Haloarcula spp. (proteolytic) and Halococcus spp. (non-proteolytic). The following media were alternatively used for the isolation of extremely halophilic bacteria: IRAM; Formulation of Gibbons and collaborators, Cod Milk agar, and SAMm. IRAM and Gibbons were also used enriched with milk. In the SAMm medium, there were obtained count values similar or higher than the ones of the traditional media; besides the simplicity of its elaboration, the possibility to obtain positive results two or three days earlier also added to its benefit. Consequently, it can be considered an alternative to the media traditionally used for the studied halophilic bacteria.

Partial chemical and functional characterization of milk whey products obtained by different processes

Whey protein samples (S-1 to S-5) were tested in vivo and in vitro for nutritional properties and selected bioactivities. Weanling male Wistar rats fed modified AIN-93G (12 g protein.100 g-1) diets for 21 days were used the in vivo studies. The nutritional parameters did not differ among the protein diets tested. Erythrocyte glutathione content was considered high and was higher for S-3, but liver glutathione was the same for all dietary groups. For S-3, cytokine secretion (IL-10 and TNF-α) by human peripheral blood mononuclear cells (in RPMI-1640 medium) was higher in the absence of antigen than in the presence of BCG antigen. Interleukin-4 secretion was repressed in all treatments. The IC50, whey protein concentration required to inhibit 50% of the melanoma cell proliferation, was 2.68 mg.mL-1 of culture medium for the S-3 sample and 3.66 mg.mL-1 for the S-2 sample. Based on these results, it was concluded that S-3 (whey protein concentrate enriched with TGF-β and lactoferrin) produced better nutritional and immunological responses than the other products tested.

Modeling of allergen proteins found in sea food products

Shellfish are a source of food allergens, and their consumption is the cause of severe allergic reactions in humans. Tropomyosins, a family of muscle proteins, have been identified as the major allergens in shellfish and mollusks species. Nevertheless, few experimentally determined three-dimensional structures are available in the Protein Data Base (PDB). In this study, 3D models of several homologous of tropomyosins present in marine shellfish and mollusk species (Chaf 1, Met e1, Hom a1, Per v1, and Pen a1) were constructed, validated, and their immunoglobulin E binding epitopes were identified using bioinformatics tools. All protein models for these allergens consisted of long alpha-helices. Chaf 1, Met e1, and Hom a1 had six conserved regions with sequence similarities to known epitopes, whereas Per v1 and Pen a1 contained only one. Lipophilic potentials of identified epitopes revealed a high propensity of hydrophobic amino acids in the immunoglobulin E binding site. This information could be useful to design tropomyosin-specific immunotherapy for sea food allergies.

Antioxidants in yacon products and effect of long term storage

Yacon (Smallanthus sonchifolius (Poepp. and Endl.) H. Robinson) is a storage root originally grown in the Andean highlands. The fresh roots are perishable and quickly turn brown during handling and processing. Aiming to prolong shelf-life and to preserve the antioxidant compounds in yacon roots, 3 mm thick yacon slices were dried in a drying cabinet at 40, 50, and 60 ºC to a moisture content of 10-14%, and yacon strips were sun dried to a moisture content of 15-20%. The total phenolic content was measured by the Folin-Ciocalteu method, and the quenching capacity was evaluated by measuring the amount of DPPH (1,1-diphenyl-2-pidrylhydrazyl) inhibited in samples after drying and after 7 months of storage. The results showed that it is possible to preserve the antioxidant capacity in yacon after cabinet or sun drying. Both yacon chips and strips presented total phenolic content values similar to those of fresh yacon roots. Both products also showed a high inhibition capacity of DPPH (1,1-diphenyl-2-pidrylhydrazyl). A significant decrease in the phenolic content was observed in the yacon chips after storage, which indicates that the sun dried strips are more suitable for storage.

Rosemary extract and celery-based products used as natural quality enhancers for colonial type salami with different ripening times

This study aimed to evaluate the use of rosemary (Rosmarinus officinalis) extract (RE), celery (Apium graveolis), and low levels of NO3 and NO2 as natural agents to enhance the quality of colonial salami. Salami was produced according to three treatments: (A) Control: 0.1% curing salt; (B) Rosemary: 0.05% curing salt + 0.5% RE (rosemary extract); and (C) Rosemary+celery: 0.14% Veg 503 + 0.27% Veg 504 (sea salt plus celery) + 0.5% of RE (rosemary extract). There was no effect (P > 0.05) of the treatments on water activity, Na content, and residual NO3 and NO2. Fatty acids C18:2 and C20:4 were reduced (P < 0.05) during the ripening period in the Control treatment indicating possible oxidation. The use of celery resulted in lower pH values (P < 0.05) in the salami. Reduced addition of NO3 and NO2 resulted in salami lighter in color (higher L* values, P < 0.05) at the 12th day of ripening. In conclusion, celery-based products proved to be an effective source of NO2 and NO3 for color development, but the low pH of the product indicates the need for better evaluation of its use in fermented salami. The RE (rosemary extract) reduced fat oxidation in salami, but this needs further evaluation.

Deep-fat frying of meat products in palm olein

This study investigated the discontinuous frying of breaded meat products in palm olein in a 28 L-electric fryer maintained at 182 ºC for 8 hours a day. Three 400-500 g batches of meat products were fried for 4.5 minutes daily. For comparison purpose, thermoxidation tests were performed using inert material with added moisture and without the addition of f ood (heating only). The total polar compound content did not reach the 25% limit, and nor did the formation of polymerized products exceed 5%, which indicates the good frying performance of palm olein for frying. Other analytical parameters and rapid tests were also evaluated. The sensory attributes, such as odor, colour, and foam formation determined when the frying oils should be discarded. The addition of water to the inert material contributed to the final value of 1.00 ± 0.01% (in palmitic acid), while the oil subjected only to heating reached respectively 0.26 ± 0.02%, and the oils used to fry breaded meat and breaded chicken reached 0.38 ± 0.00% and 2.35 ± 0.01%, respectively. This suggests a protective effect of the water during frying since the oil subjected only to heating was more prone to degradation.

Isolation and characterization of bacterial strains with a hydrolytic profile with potential use in bioconversion of agroindustial by-products and waste

There is a trend towards the use of novel technologies nowadays, mainly focused on biological processes, for recycling and the efficient utilization of organic residues that can be metabolized by different microorganisms as a source of energy. In the present study the isolation of bacterial strains from six different agro-industrial by-products and waste was performed with the objective of evaluating their hydrolytic capacities and suitability for use in bioconversion of specific substrates. The 34 isolated strains were screened in specific culture media for the production of various hydrolytic enzymes (lipase, protease, cellulase, and amylase). It was found that 28 strains exhibited proteolytic activity, 18 had lipolytic activity, 13 had caseinolytic activity, 15 had amylolytic activity, and 11 strains exhibited cellulolytic activity. The strains that showed the highest hydrolytic capacities with biotechnological potential were selected, characterized genotipically, and identified as Bacillus, Serratia, Enterococcus, Klebsiella, Stenotrophomonas, Lactococcus, and Escherichia genera. It was concluded that the strain isolates have a high potential for use in the bioconversion of agro-industrial waste, both as a pure culture and as a microbial consortium.

Detection of genetically modified maize events in Brazilian maize-derived food products

The Brazilian government has approved many transgenic maize lines for commercialization and has established a threshold of 1% for food labeling, which underscores need for monitoring programs. Thirty four samples including flours and different types of nacho chips were analyzed by conventional and real-time PCR in 2011 and 2012. The events MON810, Bt11, and TC1507 were detected in most of the samples, and NK603 was present only in the samples analyzed in 2012. The authorized lines GA21, T25, and the unauthorized Bt176 were not detected. All positive samples in the qualitative tests collected in 2011 showed a transgenic content higher than 1%, and none of them was correctly labeled. Regarding the samples collected in 2012, all positive samples were quantified higher than the threshold, and 47.0% were not correctly labeled. The overall results indicated that the major genetically modified organisms detected were MON810, TC1507, Bt11, and NK603 events. Some industries that had failed to label their products in 2011 started labeling them in 2012, demonstrating compliance with the current legislation observing the consumer rights. Although these results are encouraging, it has been clearly demonstrated the need for continuous monitoring programs to ensure consumers that food products are labeled properly.