Food Substrates Research Articles

Exploring lactic acid bacteria diversity for better fermentation of plant-based dairy alternatives

Plant-based foods have risen in popularity in recent years including a number of dairy alternative products. Fermentation has the potential to support the development of innovative plant-based foods with enhanced flavour, texture and nutritional quality. Lactic acid bacteria (LAB) have been used for thousands of years to carry out fermentation of a wide variety of food substrates through production of organic acids and flavour compounds. However, LAB strains used in dairy fermentations are commonly found to be suboptimal in their metabolism of plant substrates, so efforts to identify alternative strains are needed. We provide an overview of the plant-based milk alternative category and explore screening approaches (including citizen-science efforts) to identify new LAB that hold potential in acidification and flavour formation of plant-based substrates.

Combined use of analyte protectants and precolumn backflushing for a robust, high-throughput quantitative determination of aroma compounds in cigarette mainstream smoke by gas chromatography-tandem mass spectrometry

Trace analysis of multi-targets in complex matrices such as cigarette smoke has always been a great challenge for analysts. In this paper, a high-throughput qualitative and quantitative method was developed and validated to determine 559 aroma compounds in mainstream smoke using gas chromatography-tandem mass spectrometry. Among four commonly used extraction solvents, dichloromethane showed obvious advantages in extracting the target aroma compounds with different polarity. An analyte protectant mixture consisting of 3-methoxy-1,2-propanediol, 1,2-octandiol, 1,2-nonanediol, and 1,2-tetradecanediol was first presented to compensate for the matrix effect, which was suitable for solvents of a wide polarity range such as hexane, dichloromethane, acetone, acetonitrile, and methanol. Moreover, the introduction of precolumn backflushing markedly improved the instrument robustness in analyzing complex cigarette smoke. The results showed that the system retained good stability after 30 days of injection. The proposed method performed well in terms of key validation parameters: accuracy (70.3–118.8% for 552 compounds), inter/intraday precision (0.1–10.7% and 0.2–18.2%), and sensitivity (limit of detection 0.12–102.54 ng/mL). Finally, this method was successfully applied to analyze 12 different commercial cigarette brands. The proposed method has good application prospects based on its robustness and may be used as a potential tool to transfer the cigarette design from an experience-dependent mode to a digital design mode. This method also shows potential in assaying aroma compounds in essentials, food or plant-based substrates.

Detection of fungal and bacterial contamination of hazelnut and determination of aflatoxin B by HPLC method in Isfahan, Iran.

Background and Purpose: Due to the fact that fungal species, such as Aspergillus flavus and Aspergillus parasiticus produce carcinogenic and mutagenic aflatoxins and have the potential to produce fungal secondary metabolites, fungal contamination should be avoided. This study was conducted using the HPLC method and aimed to examine the fungal contamination of Isfahan hazelnuts in order to identify the presence of Aflatoxins.Materials and Methods: In total, 100 samples of hazelnuts were randomly collected from supermarkets in Isfahan. The samples were then cultured on Sabouraud dextrose agar media and analyzed to determine fungal contaminations. The aflatoxin analysis was carried out using the HPLC method.Results: It was discovered that nine genera of fungi, namely Aspergillus, Penicillium, Rhizopus, Ulocladium, Alternaria, Drechselera, Trichothecium, Scopulariopsis, and Mucor were identified in 78% of the samples. Samples contaminated with Aspergillus flavus (22 samples) were studied to determine the presence of aflatoxin. The results showed that 16 (72.72%) of the samples were contaminated with AFB1, AFB2, and AFG2 and the mean concentrations were 0.926, 0.563, and 0.155 ng/g, respectively.Conclusion: Some parameters that affect mycotoxin production are temperature, food substrate, the strain of the mold, and other environmental factors. Due to the toxigenic quality of some of these fungi and their hazard to human health, it is crucial that fungal contamination and aflatoxin identification tests are carried out before certain products are made available to the mass market.

The Role of Segmented Filamentous Bacteria in Immune Barrier Maturation of the Small Intestine at Weaning.

The microbiological, physical, chemical, and immunological barriers of the gastrointestinal tract (GIT) begin developing in utero and finish maturing postnatally. Maturation of these barriers is essential for the proper functioning of the GIT. Maturation, particularly of the immunological barrier, involves stimulation by bacteria. Segmented filamentous bacteria (SFB) which are anaerobic, spore-forming commensals have been linked to immune activation. The presence and changes in SFB abundance have been positively correlated to immune markers (cytokines and immunoglobulins) in the rat ileum and stool samples, pre- and post-weaning. The abundance of SFB in infant stool increases from 6 months, peaks around 12 months and plateaus 25 months post-weaning. Changes in SFB abundance at these times correlate positively and negatively with the production of interleukin 17 (IL 17) and immunoglobulin A (IgA), respectively, indicating involvement in immune function and maturation. Additionally, the peak in SFB abundance when a human milk diet was complemented by solid foods hints at a diet effect. SFB genome analysis revealed enzymes involved in metabolic pathways for survival, growth and development, host mucosal attachment and substrate acquisition. This narrative review discusses the current knowledge of SFB and their suggested effects on the small intestine immune system. Referencing the published genomes of rat and mouse SFB, the use of food substrates to modulate SFB abundance is proposed while considering their effects on other microbes. Changes in the immune response caused by the interaction of food substrate with SFB may provide insight into their role in infant immunological barrier maturation.

Continuous hydrolysis of milk proteins in membrane reactors of various configurations

Introduction. The article provides a review of technologies for membrane fractionation of various hydrolyzed food substrates in membrane bioreactors (MBR). In food industry, MBRs are popular in functional food production, especially in the processing of whey, which is a very promising raw material due to its physicochemical composition.
 Study objects and methods. The research was based on a direct validated analysis of scientific publications and featured domestic and foreign experience in MBR hydrolysis of protein raw material.
 Results and discussion. The MBR hydrolysis of proteins combines various biocatalytic and membrane processes. This technology makes it possible to intensify the biocatalysis, optimize the use of the enzyme preparation, and regulate the molecular composition of hydrolysis products. The paper reviews MBRs based on batch or continuous stirring, gradient dilution, ceramic capillary, immobilized enzyme, etc. Immobilized enzymes reduce losses that occur during the production of fractionated peptides. Continuous MBRs are the most economically profitable type, as they are based on the difference in molecular weight between the enzyme and the hydrolysis products.
 Conclusion. Continuous stirred tank membrane reactors have obvious advantages over other whey processing reactors. They provide prompt separation of hydrolysates with the required biological activity and make it possible to reuse enzymes.

Improving Phenolic Bioactive-Linked Functional Qualities of Sweet Potatoes Using Beneficial Lactic Acid Bacteria-Based Biotransformation Strategy

Beneficial lactic acid bacteria (LAB) based fermentation is an effective biotransformation strategy to preserve and improve the human health-supporting functional qualities of plant-based food substrates. In this study, a food grade strain of Lactiplantibacillus plantarum was recruited to improve the retention, stability, and bioavailability of phenolic bioactives to enhance the antioxidant, anti-hyperglycemic, and anti-hypertensive functional qualities of three flesh-colored sweet potato varieties, Murasaki (off-white-fleshed), Evangeline (orange-fleshed), and NIC-413 (purple-fleshed). Liquid (cold water) extracts of the sweet potatoes, which are relevant for food grade applications, were fermented for 72 h at 37 °C. Total soluble phenolic content, phenolic profile, antioxidant, anti-hyperglycemic, and anti-hypertensive benefits relevant functional properties of fermented and unfermented sweet potato extracts were evaluated at 0, 24, 48, and 72 h time points using in vitro assay models. Overall, high total soluble phenolic content and total antioxidant activity were observed at 24 h, retaining this high level even after 72 h of fermentation. Additionally, moderate to high α-amylase, α-glucosidase, and angiotensin-I-converting enzyme inhibitory activities were observed in the fermented sweet potato extracts. The results suggested that LAB-based fermentation is an effective post-harvest processing strategy for a higher retention of phenolic bioactives and concurrently improves the human health protective bioactive functional qualities of sweet potatoes.

The timing of intermittent hypoxia differentially affects macronutrient intake and energy substrate utilization in mice.

Sleep apnea is a common sleep disorder characterized by periodic breathing cessation and intermittent hypoxia (IH). Although previous studies have demonstrated that IH alone can influence metabolic outcomes such as body weight, it remains unclear how the timing of IH can specifically affect these outcomes. Here, we examine how pairing 10-h periods of IH to either the animals' resting phase (e.g., IH during the day) or active phase (e.g., IH during the night) differentially affects body weight, macronutrient selection, energy expenditure, respiratory exchange rate, and glucose tolerance. We find that in contrast to mice exposed to IH during the night, mice exposed to IH during the day preferentially decrease their carbohydrate intake and switch to fat metabolism. Moreover, when the IH stimulus was removed, mice that had been exposed to day IH continued to eat a minimal amount of carbohydrates and consumed a higher percentage of kilocalorie from fat for at least 5 days. These data demonstrate that food choice and substrate utilization are secondary to the timing of IH but not IH itself. Taken together, these data have key clinical implications for individuals with sleep apnea and particularly those who are also experiencing circadian disruption such as night-shift workers.NEW & NOTEWORTHY Pairing repeated hypoxic episodes to a mouse's resting phase during the day preferentially decreases carbohydrate intake and results in a switch to metabolic fat oxidation. These data indicate that the timing of intermittent hypoxia should be considered when calculating sleep apnea's effects on metabolic outcomes.

Quantitative analysis of FQs antibiotics content in FMF using THz spectral and imaging technology

Rapid and accurate detection of fluoroquinolones (FQs) antibiotics residues in food substrate are of great significance to food safety. In this study, terahertz spectroscopy was employed to conduct the spectral and imaging analysis to explore its feasibility for detection concentrations of FQs in fish meal feeds (FMF). Four methods (frequency of maximum difference in frequency-domain, characteristic absorption peak, successive projections algorithm and stepwise regression) were used to selected characteristic frequencies of sample. Terahertz imaging was formed at selected characteristic frequency and back propagation neural network was used to establish quantitative evaluation models to select optimal characteristic imaging frequency. Finally, relationship between concentrations of FQs and their gray values was revealed, and each data had a small range of error bar. The results showed that terahertz spectral and imaging technique can visualize norfloxacin and enrofloxacin concentrations in FMF precisely. This study explored a brand-new visualization method for quantitative detection of FQs in FMF based on terahertz spectral and imaging technology.

Improving Phenolic-Linked Antioxidant, Antihyperglycemic and Antibacterial Properties of Emmer and Conventional Wheat Using Beneficial Lactic Acid Bacteria

Beneficial lactic acid bacteria (LAB)-based fermentation is an effective bioprocessing approach to improve human-health-targeted functional benefits of plant-based food substrates, such as cereal grains. Previously, we observed high phenolic bioactive-linked antioxidant and anti-hyperglycemic properties in whole grain Emmer (hulled). In this study, beneficial LAB (Lactiplantibacillus plantarum) was recruited to ferment (0–72 h) aqueous extracts (0.4 g/mL concentration) of previously optimized hulled Emmer wheat and conventional red spring wheat cv. Barlow. The fermented and unfermented (control) wheat extracts were analyzed for phenolic content, phenolic profile, antioxidant activity, and antihyperglycemic properties (α-amylase and α-glucosidase enzyme inhibitory activity) using in vitro assay models. Additionally, antimicrobial activity against pathogenic bacteria Helicobacter pylori, and potential prebiotic activity supporting the growth of beneficial Bifidobacterium longum were also investigated. Improvement in antioxidant activity and antihyperglycemic functional benefits were observed, while soluble phenolic content remained high after 72 h fermentation. Antimicrobial activity against H. pylori was also observed in 48 and 72 h fermented wheat extracts. This study provides an insight into the efficacy of LAB-based fermentation as a safe bioprocessing tool to design health-targeted functional foods and ingredients from underutilized whole grains like Emmer for targeting type 2 diabetes dietary benefits.

A sampling survey of enterococci within pasteurized, fermented dairy products and their virulence and antibiotic resistance properties.

Globally, fermented foods (FFs), which may be traditional or industrially-produced, are major sources of nutrition. In the traditional practice, the fermentation process is driven by communities of virtually uncharacterized microflora indigenous to the food substrate. Some of these flora can have virulent or antibiotic resistance properties, posing risk to consumers. Others, such as Enterococcus faecalis and Enterococcus faecium, may also be found in such foods. Enterococci that harbor antibiotic resistance or virulence factors can cycle among animals, food, humans and the environment, thereby transferring these harmful properties at the gene level to harmless commensals in the food matrix, animals and humans. In this work, several microbial isolates obtained from different FF sources were analyzed for their identity and virulence and/or antibiotic resistance properties. For identification aiming at enterococci, isolates that were Gram-positive and catalase- and oxidase-negative were subjected to multiple tests including for growth in broth containing 6.5% NaCl, growth and hydrolytic activity on medium containing bile-esculin, hemolytic activity on blood agar, and growth at 45°C and survival after incubation at 60°C for 30 min. Furthermore, the isolates were tested for susceptibility/resistance to a select group of antibiotics. Finally, the isolates were molecularly-characterized with respect to species identity and presence of virulence-encoding genes by amplification of target genes. Most sources contained enterococci, in addition to most of them also containing Gram-negative flora. Most of these also harbored virulence factors. Several isolates were also antibiotic-resistant. These results strongly suggest attention should be given to better control presence of such potentially pathogenic species.

ComBase Models Are Valid for Predicting Fate of Listeria monocytogenes on 10 Whole Intact Raw Fruits and Vegetables

Listeria monocytogenes was associated with more than 60 produce recalls, including tomato, cherry, broccoli, lemon, and lime, between 2017 and 2020. This study describes the effects of temperature, time, and food substrate as factors influencing L. monocytogenes behavior on whole intact raw fruits and vegetables. Ten intact whole fruit and vegetable commodities were chosen based on data gaps identified in a systematic literature review. Produce investigated belong to major commodity families: Ericaceae (blackberry, raspberry, and blueberry), Rutaceae (lemon and mandarin orange), Roseaceae (sweet cherry), Solanaceae (tomato), Brassaceae (cauliflower and broccoli), and Apiaceae (carrot). A cocktail of five L. monocytogenes strains that included clinical, food, or environmental isolates linked to foodborne outbreaks was used to inoculate intact whole fruits and vegetables. Samples were incubated at 2, 12, 22, 30, and 35°C with relative humidities matched to typical real-world conditions. Foods were sampled (n = 6) for up to 28 days, depending on temperature. Growth and decline rates were estimated using DMFit, an Excel add-in. Growth rates were compared with ComBase modeling predictions for L. monocytogenes. Almost every experiment showed initial growth, followed by subsequent decline. L. monocytogenes was able to grow on the whole intact surface of all produce tested, except for carrot. The 10 produce commodities supported growth of L. monocytogenes at 22 and 35°C. Growth and survival at 2 and 12°C varied by produce commodity. The standard deviation of the square root growth and decline rates showed significantly larger variability in both growth and decline rates within replicates as temperature increased. When L. monocytogenes growth occurred, it was conservatively modeled by ComBase Predictor, and growth was generally followed by decreases in concentration. This research will assist in understanding the risks of foodborne disease outbreaks and recalls associated with L. monocytogenes on fresh whole produce.

A rapid and sensitive lateral flow immunoassay (LFIA) for the detection of gluten in foods

The gluten protein found in a variety of cereal grains is a food allergen that can elicit a spectrum of immuno-inflammatory responses in people. Consumer awareness has prompted changes in food labeling requirements, expanded gluten-free food product availability and increased demand for effective gluten testing methodologies. To meet the challenges associated with gluten testing from diverse and complex foods we developed a lateral flow immunoassay (LFIA) using a pair of novel gliadin monoclonal antibodies (MAbs). Using a visual gold reporter, we show sensitive gluten detection (150 ng/mL) from complex food substrates using a fast (<5 min) and easy testing methodology. In this report we characterize the binding properties of a cohort of newly generated gliadin monoclonal antibodies suitable for gluten detection using multiple assay formats and introduce a novel plug-n-play test strip platform with integrated test components in a single-use format.

Age-Related Changes in the Yeast Component of the Drosophila melanogaster Microbiome

Drosophila melanogaster fruit flies are an important model for studying the multifaceted interactions between a multicellular organism and its microbiome. The nature of these interactions is largely determined by the regular changes in abundance and composition of the microbiome that occur during the host’s life. The currently available data on age- and life cycle stage-related changes in the Drosophila microbiome relate mainly to its bacterial component, while little is known about such changes in the equally important yeast component. The present work describes the quantitative and qualitative composition of the yeast component of the D. melanogaster microbiome in three laboratory lines, reared under different conditions, at four developmental stages: late larvae and adults aged 1, 7, and 14 days after eclosion. In all three lines, the total yeast abundance changed similarly with the age of insects, with the highest and lowest yeast counts in 7- and 1-day adults, respectively. In the fly lines reared on moderately unfavorable substrates supplemented with 2 and 4% NaCl, the abundance and species diversity of yeasts at all four developmental stages was higher than in the flies reared on a standard (favorable) food substrate. Our results indicate the inconstancy of the yeast component of the D. melanogaster microbiome and its regular changes with the insect’s age, which must be taken into account when studying the relationships between symbiotic yeasts and their hosts.

Stewardship of Wild and Farmed Edible Insects as Food and Feed in Sub-Saharan Africa: A Perspective.

Edible insects have gained popularity as alternative food resources in the face of climate change and increasing carbon and environmental footprints associated with conventional agricultural production. Among the positive attributes that make edible insects suitable as food and feed substrates include rapid reproduction, high energy conversion efficiency, wide distribution, diversity, reduced greenhouses gases and ammonia emissions, possibility to reduce waste and high nutritional composition. In Sub-Saharan Africa, considerable scientific data exist on use of insects as food and livestock feed. However, coherent policies regarding safety, sustainability, trade and regulation of insects as food and animal feed are lacking. The benefits associated with edible insects are likely to accrue in Sub-Saharan Africa through use of a combination of approaches such as ensured sustainable utilization of edible insects in the wild, preservation of traditional conservation, harvesting and consumption practices, development of captive mass production schemes and strengthening robust value chains to incentivise indigenous participants. Collectively these approaches are referred to as the steward and use of insects as food and animal feed. This paper examines the policy frameworks that exist to support the use of edible insects as food and feed on the African continent. This investigation employed a literature review focussing on national policies in selected African countries to assess the relevance to edible insects. Using a baseline of more than 10 edible insect species consumed, 10 country cases in Sub-Saharan Africa were used to support our in-depth examination of the policy situation that may support good stewardship of edible insects as food and feed. Focus on how policies encompassing biodiversity, natural resources, culture, education, research, technology development, trade, health and nutrition and how that could be improved to support inclusivity of edible insects is discussed. We conclude by proposing a pathway that may accelerate recognition and valorisation of edible insects as important food and feed resources in Sub-Saharan Africa including improving policies to support good stewardship of these resources for sustainability.

Starvation Alters Gut Microbiome in Black Soldier Fly (Diptera: Stratiomyidae) Larvae.

Unlike for vertebrates, the impact of starvation on the gut microbiome of invertebrates is poorly studied. Deciphering shifts in metabolically active associated bacterial communities in vertebrates has led to determining the role of the associated microbiome in the sensation of hunger and discoveries of associated regulatory mechanisms. From an invertebrate perspective, such as the black soldier fly, such information could lead to enhanced processes for optimized biomass production and waste conversion. Bacteria associated with food substrates of black soldier fly are known to impact corresponding larval life-history traits (e.g., larval development); however, whether black soldier fly larval host state (i.e., starved) impacts the gut microbiome is not known. In this study, we measured microbial community structural and functional shifts due to black soldier fly larvae starvation. Data generated demonstrate such a physiological state (i.e., starvation) does in fact impact both aspects of the microbiome. At the phylum level, community diversity decreased significantly during black soldier fly larval starvation (p = 0.0025). Genus level DESeq2 analysis identified five genera with significantly different relative abundance (q < 0.05) across the 24 and 48 H post initiation of starvation: Actinomyces, Microbacterium, Enterococcus, Sphingobacterium, and Leucobacter. Finally, we inferred potential gene function and significantly predicted functional KEGG Orthology (KO) abundance. We demonstrated the metabolically active microbial community structure and function could be influenced by host-feeding status. Such perturbations, even when short in duration (e.g., 24 H) could stunt larval growth and waste conversion due to lacking a full complement of bacteria and associated functions.

Twists and Turns in the Salicylate Catabolism of Aspergillus terreus, Revealing New Roles of the 3-Hydroxyanthranilate Pathway.

In fungi, salicylate catabolism was believed to proceed only through the catechol branch of the 3-oxoadipate pathway, as shown, e.g., in Aspergillus nidulans However, the observation of a transient accumulation of gentisate upon the cultivation of Aspergillus terreus in salicylate medium questions this concept. To address this, we have run a comparative analysis of the transcriptome of these two species after growth in salicylate using acetate as a control condition. The results revealed the high complexity of the salicylate metabolism in A. terreus with the concomitant positive regulation of several pathways for the catabolism of aromatic compounds. This included the unexpected joint action of two pathways-3-hydroxyanthranilate and nicotinate-possibly crucial for the catabolism of aromatics in this fungus. Importantly, the 3-hydroxyanthranilate catabolic pathway in fungi is described here for the first time, whereas new genes participating in the nicotinate metabolism are also proposed. The transcriptome analysis showed also for the two species an intimate relationship between salicylate catabolism and secondary metabolism. This study emphasizes that the central pathways for the catabolism of aromatic hydrocarbons in fungi hold many mysteries yet to be discovered.IMPORTANCE Aspergilli are versatile cell factories used in industry for the production of organic acids, enzymes, and pharmaceutical drugs. To date, bio-based production of organic acids relies on food substrates. These processes are currently being challenged to switch to renewable nonfood raw materials-a reality that should inspire the use of lignin-derived aromatic monomers. In this context, aspergilli emerge at the forefront of future bio-based approaches due to their industrial relevance and recognized prolific catabolism of aromatic compounds. Notwithstanding considerable advances in the field, there are still important knowledge gaps in the central catabolism of aromatic hydrocarbons in fungi. Here, we disclose a novel central pathway, 3-hydroxyanthranilate, defying previously established ideas on the central metabolism of the aromatic amino acid tryptophan in Ascomycota We also observe that the catabolism of the aromatic salicylate greatly activated the secondary metabolism, furthering the significance of using lignin-derived aromatic hydrocarbons as a distinctive biomass source.

Development and Validation of a Method to Simultaneously Determine Multiple Sterols in Diversiform Food Substrates with UPLC-MS/MS

Sterols play an essential part in physiological activities of almost all creatures. However, there is a lack of a widely applicable routine method to investigate various sterols with both saturated and unsaturated forms in diversiform food materials. In this study, a new UPLC-MS/MS method with wider extensive applicability has been developed to fill this blank, which is considered time and cost saving, and can improve labor efficiency. The Agilent Eclipse Plus C18 column and methanol-water gradient elution system were employed to improve the separation at 40 °C and the flow rate was 0.5 mL/min. The method validation parameters include precision, recovery, linearity, and limit of detection and quantification (LOD and LOQ). The recoveries of sterols in all food matrices and the inter-day and intra-day precisions represented by RSDs were all within the recommended range of chemical analysis. The LODs and LOQs in different types of samples were in range of 0.0036–0.68 μg/mL and 0.01–2.0 μg/mL, respectively. All the results demonstrated that this method was sensitive and accurate enough. Additionally, the acid hydrolysis was found closely related to the degradation of unsaturated sterols in the pretreatment.

Aspergillus derived mycotoxins in food and the environment: Prevalence, detection, and toxicity.

Aspergillus species are the paramount ubiquitous fungi that contaminate various food substrates and produce biochemicals known as mycotoxins. Aflatoxins (AFTs), ochratoxin A (OTA), patulin (PAT), citrinin (CIT), aflatrem (AT), secalonic acids (SA), cyclopiazonic acid (CPA), terrein (TR), sterigmatocystin (ST) and gliotoxin (GT), and other toxins produced by species of Aspergillus plays a major role in food and human health. Mycotoxins exhibited wide range of toxicity to the humans and animal models even at nanomolar (nM) concentration. Consumption of detrimental mycotoxins adulterated foodstuffs affects human and animal health even trace amounts. Bioaerosols consisting of spores and hyphal fragments are active elicitors of bronchial irritation and allergy, and challenging to the public health. Aspergillus is the furthermost predominant environmental contaminant unswervingly defile lives with a 40-90 % mortality risk in patients with conceded immunity. Genomics, proteomics, transcriptomics, and metabolomics approaches useful for mycotoxins' detection which are expensive. Antibody based detection of toxins chemotypes may result in cross-reactivity and uncertainty. Aptamers (APT) are single stranded DNA (ssDNA/RNA), are specifically binds to the target molecules can be generated by systematic evolution of ligands through exponential enrichment (SELEX). APT are fast, sensitive, simple, in-expensive, and field-deployable rapid point of care (POC) detection of toxins, and a better alternative to antibodies.

Metabolic profiles for the pyrrolizidine alkaloid neopetasitenine and its metabolite petasitenine in humans extrapolated from rat in vivo and in vitro data sets using a simplified physiologically based pharmacokinetic model.

Naturally occurring food substances may constitute safety hazards. The risks associated with plant-derived pyrrolizidine alkaloids have been extensively evaluated. Petasites japonicus (common Japanese name, fuki) is a widely consumed water-soluble pyrrolizidine alkaloid-producing plant. In this study, neopetasitenine (acetylfukinotoxin) was selected as a model food substrate (for which human pharmacokinetics were estimated) because of its high concentration in fuki, along with petasitenine (fukinotoxin), its carcinogenic deacetylated metabolite. Although neopetasitenine was rapidly absorbed and converted to petasitenine after oral administration of 1.0 mg/kg in rats, petasitenine was slowly cleared from plasma. Forward dosimetry was conducted using in silico simplified physiologically based pharmacokinetic (PBPK) modeling formulated on experimental pharmacokinetic rat data. From ~2 hr after the oral administration of neopetasitenine in rats, the plasma concentrations of petasitenine were higher than those of neopetasitenine under the present conditions. A human PBPK model was established following an allometric scaling approach applied to rat parameters (without considering interspecies factors) to estimate human intrinsic hepatic clearances from empirical rat values. Human in silico neopetasitenine and petasitenine plasma concentration curves were simulated after daily oral administrations of 3.0 and 1.3 mg/kg neopetasitenine. These doses were taken from reported acute/short-term cases of pyrrolizidine alkaloid toxicity. In vitro hepatotoxicity of neopetasitenine and petasitenine was caused by their high concentrations in the medium for human hepatocyte-like cell line HepaRG cells as an index of lactate dehydrogenase leakage. Neopetasitenine was estimated to be rapidly absorbed and converted to deacetylated carcinogenic petasitenine, even after hepatotoxic doses of 1.0 mg/kg in humans. If the water-soluble pyrrolizidine alkaloid-producing plant P. japonicus were daily consumed as food, current simulation results suggest that dangerous amounts of deacetylated petasitenine could be continuously present in human plasma.

Biological aspects of Caligo teucer (Lepidoptera: Nymphalidae) with banana tree leaves

Caligo teucer (Linnaeus, 1758) is widely distributed in Argentina, Bolivia, Brazil and Ecuador. The objective was to study biological aspects of Caligo teucer japetus Stichel, 1903 with banana leaves, Musa sapientium L. (Zingiberales: Musaceae), in the butterfly garden, under environmental conditions, and in the laboratory of biological control of insects at the Universidade Federal de Viçosa in Viçosa, Minas Gerais state, Brazil at 24 ± 2 oC, 68 ± 10% relative humidity and 12 hours photophase. The duration of the egg incubation, larvae, pupa and egg to adult periods of C. teucer japetus were, respectively, 11.8 ± 0.1; 53.9 ± 0.9; 17.9 ± 0.3 and 82.6 ± 1.0 days for females, and 11.8 ± 0.1; 50.3 ± 0.6; 18.4 ± 0.3 and 79.4 ± 0.6 days for males in cages in the laboratory. The longevity of C. teucer japetus adults was 26.0 ± 10.4 and 47.5 ± 8.7 for females and 24.7 ± 3.5 and 35.4 ± 15.7 for males in the butterfly garden and in laboratory cages, respectively. The high survival and the relatively short period of development of its immature stages confirm that banana leaves are an adequate food substrate for the development and survival of Caligo teucer japetus.