Food Levels Research Articles

Organophosphate flame retardants and their metabolites in paired dog food and urine: Pet exposure through food consumption.

Companion dogs are exposed to various chemicals. However, our understanding of the sources and pathways of chemical exposure in pets remains limited. In this study, we collected urine samples from 47 dogs and corresponding samples of the food they consumed to analyze the concentrations and dietary exposure to organophosphate flame retardants (OPFRs) and their metabolites (mOPFRs). Triphenyl phosphate (TPHP) and its metabolite, diphenyl phosphate (DHPH), were the predominant compounds detected in dog food and urine samples. The concentration of mOPFRs in urine decreased as body weight increased; however, neither sex nor age significantly influenced mOPFR levels in dog urine. The estimated daily intake of OPFRs (343 ng/kg bw/day) through food consumption (EDIfood) was comparable to the previously reported levels of polycyclic aromatic hydrocarbons (324 ng/kg bw/day) and higher than those of pesticides (214 ng/kg bw/day), parabens (120 ng/kg bw/day), and polychlorinated biphenyls (103 ng/kg bw/day). By calculating the ratio of EDIfood to the cumulative daily intake based on urinary mOPFR concentrations, it was found that dietary sources contributed to 66% of the total TPHP exposure in dogs. This finding was further supported by Spearman's correlation analysis between parent OPFR concentrations in dog food and mOPFR levels in urine (p < 0.01), indicating that dietary intake may be one of the most significant exposure pathways for OPFRs in dogs. To the best of our knowledge, this is the first study to investigate the levels of OPFR exposure in paired dog food and urine samples.

EFFECT OF AFLATOXIN EXPOSURE IN LIVESTOCK AND PUBLIC HEALTH: REVIEW

Aflatoxins are toxic metabolites produced by the fungi Aspergillus parasiticus and Aspergillus flavus, which commonly infest various nutritious foods and animal feed. Given the widespread occurrence of aflatoxins and their significant impact on livestock and public health, understanding the mechanisms of toxicity, routes of exposure and economic implications is crucial. This review aims to investigate the causes and effects of aflatoxin exposure on both human and animal health while proposing strategies for preventing and controlling contamination. Aflatoxin contamination impacts the entire food chain, affecting the production, storage, processing, trade and consumption of both plant and animal products. Its consequences extend to human health, livestock welfare, agricultural productivity, environmental integrity and trade, particularly in regions with inadequate aflatoxin control measures. Aflatoxicosis can result in acute mortality, cancer, immune suppression and other chronic health issues. Effective control measures include pre-harvest interventions, careful management during harvest and post-harvest decontamination. Strategies such as selecting resistant crop varieties, employing biological decontamination using microorganisms, physically removing contaminated materials and chemically inactivating aflatoxins are crucial for prevention. Regulating aflatoxin levels in food and feed is essential for protecting public health and promoting equitable trade, necessitating the establishment and enforcement of maximum allowable limits.

Keeping toxigenic Aspergillus section Flavi and aflatoxin contamination at bay by deploying atoxigenic-based biocontrol products during production of groundnut and maize in Mozambique.

Aflatoxins, produced by aflatoxigenic Aspergillus section Flavi fungi, commonly occur in groundnut and maize grown in Mozambique and have long been associated with high prevalence of liver cancer, stunting, and restricted access to lucrative international markets. Effective aflatoxin control options in the country are limited and not adequately explored. Biocontrol products based on atoxigenic strains of A. flavus provide viable aflatoxin mitigation measures but require development for Mozambique. Four hundred and sixty-eight (468) and 558 groundnut and maize farmers, respectively, voluntarily evaluated the effectiveness of two biocontrol products (Aflasafe MWMZ01 and Aflasafe MZ02), each containing as active ingredients four distinct atoxigenic isolates of A. flavus belonging to native vegetative compatibility groups (VCGs), at preventing aflatoxin contamination and displacement of aflatoxigenic fungi for 2 years in various agro-ecologies. Most groundnut and maize treated with the biocontrol products were below maximum levels for food in the European Union (EU; 85%; p < 0.01) and the United States (US; 99%; p < 0.01). In contrast, most non-treated maize and groundnut (ranging from 38 to 70%; p = 0.05) were above the EU and US maximum allowable levels for food. Aflatoxin reductions ranged from 78 to 98% (p < 0.01) in treated groundnut, and from 61 to 93% (p < 0.01) in treated maize. Toxigenic fungi were almost completely displaced from soils and crops by the applied atoxigenic active ingredients. This study revealed that the atoxigenic based biocontrol technology is effective in Mozambique at displacing aflatoxigenic fungi and reducing aflatoxin accumulation in both groundnut and maize but a combination with other management tools is encouraged for better retention of crop quality along the value chain.

Thicker is better? Impact of food consistencies on aspiration detection using IDDSI levels

Background/purposeWater is the most commonly, and often the only tested material in swallow screening. Our objective is to assess the impact of food consistencies on the reliability of trial swallows in predicting aspiration in dysphagic patients, utilizing the International Dysphagia Diet Standardisation Initiative (IDDSI) levels. MethodsAll trial swallows were evaluated using 5 ml of standardized test food with IDDSI levels of 0, 2, 4, 5. The flexible endoscopic evaluation of swallowing was used as the basis for comparison. The sensitivity, specificity, and predictive values of commonly used direct clinical signs for the detection of aspiration were analyzed, including cough with swallow (choking) and post-swallow voice change (wet voice). ResultsIDDSI 2 test food demonstrated the highest accuracy for detecting aspiration when using both clinical signs of cough (91%) and wet voice (83%). Despite reduced risk of aspiration, the percentage of silent aspiration among aspirators was significantly higher when tested with higher IDDSI levels of test food. ConclusionThe diagnostic accuracy of commonly-used clinical signs for the indication of aspiration is significantly affected by food consistency. Test foods with varying consistencies, particularly those at IDDSI level 2, should be considered during clinical swallow examinations, especially for screening purposes.

The Development of a High-Throughput Homonuclear Decoupling HSQC NMR Platform for the Determination of 10 Sex Hormones in Animal-Source Food and Medicines

Owing to their endocrine disruption effect, the hormone levels in animal-source food and medicines need to be efficiently and accurately quantified by a reliable analytical method. In the current study, by using a homonuclear decoupling and heteronuclear single quantum correlation (HSQC) experiment, coupled with non-uniform sampling (NUS) that was used to shorten the experimental time, we developed a method to quantify 10 hormone residues in animal-source products. This method was validated following the guidelines of USP–NF 2022. The application of the homonuclear decoupling (HD) technique to conventional HSQC yielded 2D spectra that exhibited excellent signal separation and specificity. For all the tested hormones, good linearity with correlation coefficients of more than 0.99 was observed in the linear range of 0.2–6 mg/0.6 mL. Satisfactory precision and recoveries of spiked animal samples were also obtained. Finally, the method was applied in residue determination of 10 hormones in real animal-source samples at the ug/g level.

Analytical methodologies for the determination of sterigmatocystin in food and current concentration levels

Sterigmatocystin (STE) is a possible human carcinogenic compound (2B) according to the International Agency for Research on Cancer classification. Structurally, STE is a precursor to aflatoxins, sharing a similar polyketide-derived biosynthetic pathway, which underscores its toxicological relevance. It has been reported to occur in a variety of foodstuffs including cereals and cereal-based products, spices, cheese, and nuts, among others. STE poses a substantial challenge to food safety and addressing this issue requires a comprehensive strategy encompassing prevention, monitoring, and regulation to protect both human and animal health from its harmful effects. The present paper presents the analytical methodologies for the determination of STE in foodstuffs and the reported levels of STE in food, based on a review of scientific publications from 2021 to 2024. Significative progress has been made in the development of analytical methodologies for STE determination in food; however, further advancements in analytical techniques, standardized protocols, and monitoring are essential to improve risk assessment and guide effective mitigation strategies.

Determinants of knowledge, attitude, and practice towards aflatoxin contamination in food and aflatoxin biomarker levels among healthy Malaysian adults

Determinants of knowledge, attitude, and practice towards aflatoxin contamination in food and aflatoxin biomarker levels among healthy Malaysian adults

Causal relationship of salt intake with osteoarthritis: A Mendelian randomization analysis.

Recent studies have demonstrated a correlation between salt intake (SI) and various diseases. However, it remains uncertain whether the relationship between SI (including salt added to food and sodium levels in urine) and benign osteoarthritis is causal. To investigate this, we conducted a 2-sample Mendelian randomization (MR) analysis to estimate the causal impact of SI on osteoarthritis (OA). A genome-wide association study of salt added to food and sodium in urine was used as the exposure, while hip osteoarthritis, knee osteoarthritis, and rheumatoid arthritis were defined as the outcomes. Inverse variance weighting (IVW) was used to calculate causal estimates, and sensitivity analyses were performed using methods including weighted mode, weighted median, MR-Egger, and Bayesian weighted MR. All statistical analyses were conducted using R software. Our results, primarily based on the IVW method, support the existence of a causal relationship between salt added to food and knee osteoarthritis (KOA). Specifically, salt added to food was associated with a decreased risk of KOA (OR = 1.248, P = .024, 95% CI: 1.030-1.512). This study is the first MR investigation exploring the causal relationship between salt added to food and KOA, potentially providing new insights and a theoretical basis for the prevention and treatment of KOA in the future.

Comparison of DNA isolation methods for GMO detection from biscuit samples

The global increase in genetically modified organism (GMO) content in feed and food products has necessitated the development of precise detection methods to differentiate between biotechnologically derived foods and those without GMOs. Despite the various regulations in different countries, an internationally consistent approach to labeling GMO products is needed. For this reason, there is a widespread need to develop effective GMO detection methods to provide reliable and transparent food safety to consumers. The first experimental step in creating accurate and reliable detection methods for GMOs is effective DNA isolation. Determining DNA isolation methods specific to different processing levels of foods is very important. This study was aimed to compare different DNA extraction methods in biscuit samples. For this reason, DNA from different biscuit samples was isolated using three different protocols (CTAB-PVP, modified CTAB-1, and modified CTAB-2). DNA samples extracted from biscuits, were evaluated regarding DNA concentration and purity. According to the results obtained, the CTAB-2 procedure generally showed the best performance in terms of both DNA amount and purity rates for biscuit samples.

The Impact of COVID-19 Pandemic on the Performance of Food and Beverage Micro and Small Enterprises (MSEs): A Case Study of Langsa City, Aceh Province

The PSBB and PPKM policies were perceived to have caused economic downturns by restricting community activities, including productive economic endeavors. The primary issue in this study is the decline in the GDP of the accommodation food, and beverage sectors in Langsa City in 2020. The research objectives are formulated as follows: (1) to analyze the impact of the Covid-19 pandemic on the income of food and beverage MSMEs in Langsa City; (2) to analyze the impact of the Covid-19 pandemic on the production levels of food and beverage MSMEs in Langsa City; (3) to analyze the impact of the Covid-19 pandemic on the assets of food and beverage MSMEs in Langsa City; and (4) to analyze the impact of the Covid-19 pandemic on the workforce of food and beverage MSMEs in Langsa City. The study was conducted in Langsa City, Aceh Province, utilizing primary data, A purposive sample of 50 MSME owners in Langsa City was selected. Respondents were not categorized by business scale (micro or small businesses). The accidental sampling method was used to determine respondents and data was collected through structured interviews using a questionnaire. The impact of the Covid-19 pandemic on the performance of food and beverage MSMEs in Langsa City was analyzed using for indicators: (1) MSME income, (2) sales volume, (3) assets, and (4) workforce size. A descriptive analysis was performed, followed by a paired sample t-test (with a = 0.05) to compare conditions before and during the Covid-19 pandemic. The analysis concluded that: (1) there was a significant decline in the income of food and beverage MSMEs in Langsa City during the Covid-19 pandemic; (2) there was a significant decline in sales volume; (3) there was a significant reduction in the value of MSME assets; and (4) there was a significant decrease in the number of employees. Keywords: Business, Assets, Number of Employees, Income, Sales, MSMEs

A multifunctional fluorescent probe for monitoring of SO2 and viscosity and its application in food, ferroptosis, and bioimaging

Inflammation is an intrinsic defense mechanism of organisms against tissue injury, characterized by biological pathways such as autophagy, depolarization, and endogenous sulfite production. Ferroptosis, a newly identified form of iron-dependent programmed cell death, leads to the accumulation of excessive lipid peroxides, resulting in changes in viscosity and SO₂ levels. Investigating the dynamic relationship between SO₂ and viscosity in these two conditions is crucial for elucidating the precise regulatory mechanisms of inflammation and ferroptosis. Here, we developed a fluorescent probe, named CNNP, which possesses dual targeting capabilities for lipid droplets and mitochondria. This innovative probe facilitates the simultaneous and precise detection of both SO₂ and viscosity, utilizing distinct emission wavelengths without cross-talk interference. Furthermore, we successfully employed this probe to determine bisulfite levels in food and herbal medicine samples, achieving high recovery rates (99.2 %–104.2 %), thereby demonstrating its practical utility. Notably, CNNP enables both exogenous and endogenous imaging of SO₂ and viscosity within cells. We observed subtle fluctuations in SO₂ levels and viscosity during inflammation and ferroptosis, as evidenced by abnormal changes in process parameters in both in vivo and in vitro levels. These findings introduce new perspective for the diagnosis and treatment of these pathological processes.

Identifying Foods within the UK diet that are rich sources of the micronutrient Queuosine (Q)

This abstract was presented as the Novel Nutrition Research Methodologies and TechnologiesTheme Highlight. Queuosine (Q) is a vital micronutrient crucial for protein translation and cellular function in humans. Deficiencies of Q have been linked to chronic illnesses, such as inflammatory bowel disease, neurodegenerative diseases, and various cancers. Human requirements for this micronutrient have not yet been established. Thus far, there has been no systematic investigation of the human diet to understand typical intakes. It is necessary to measure the levels of Q metabolites in commonly consumed foods to identify the richest dietary sources and determine Q intake. Only then can its role in human health and disease be established.This study aimed to comprehensively analyse Q distribution in the UK diet by quantifying it in foods, identifying rich sources, and ultimately, enabling the design of dietary intervention studies assessing Q absorption/bioavailability.Data from the UK National Diet and Nutrition Survey (NDNS 5Y) were processed to identify the most frequently consumed foods in 31 main categories, reflecting the dietary habits of &gt;99.5% of UK consumers. Extraction techniques were developed, including a methanol-based method for extracting free Q metabolites and a specialized approach for isolating tRNA-bound Q metabolites from various food matrices. Quantitative LC-MS/MS (SCIEX 5500+) was utilized to accurately measure queuine (q), Q, Q monophosphates (QMPs), and Q precursor (PreQ1) in food samples. These values were summed to determine Total Q levels. Additionally, four-day food diary data from 93 participants in the Northern Ireland Dietary Assessment Study (NIDAS) were analysed to determine the average daily consumption of Q metabolites in adults. Dairy sources were considered promising, so five commercial probiotic yoghurt brands were compared side-by-side.Q metabolite levels varied significantly across various food types. Total Q metabolite levels in foods ranged from 0.05ng/g to 80ng/g, with a mean level of 20ng/g. The calculated Q consumption of participants in NIDAS ranged from nil/day in some individuals to 170µg/day in others, with a typical mean intake of 18µg/day. The mean amounts (ng/g) of Total Q metabolites (tRNA-bound + free) measured in food categories were dairy 57.2 ± 9.7, meat 20.1 ± 9.9, poultry 4.9 ± 4, and plant-based milk 15.3 ± 10, fruits 2 ± 1.3, vegetables 5.3 ± 2.8, starchy foods 2.2 ± 0.7. Dairy products emerged as significant sources of Q metabolites based on these findings. Concentrations observed in shortlisted probiotic yoghurts ranged from 32 to 352 ng/g.This study determined typical Q intakes and is the first to identify Q-rich food sources in the UK diet. The highly Q-enriched probiotic yoghurt products could be used in controlled dietary intervention studies to assess Q absorption/bioavailability and this micronutrient’s role in human health and disease.

Effects of food level and fecal material on the plasticity of metamorphic traits in Asiatic toad, Bufo gargarizans, in Central China

Abstract According to Richards’ hypothesis, the presence of a nonpigmented unicellular alga in the intestinal tract of tadpoles is believed to be the inhibitory factor that affects their growth. It is proposed that thecanimals eat their fecal material containing these algal cells, which are then reintroduced into their systems when the alga is shed with the feces and dropped to the bottom. In this study, we aimed to investigate the plasticity of metamorphic traits in the Asiatic toad (Bufo gargarizans) under different combinations of fecal material and food levels. Our findings revealed that B. gargarizans tadpoles reared at high food levels exhibited accelerated larval periods but had smaller metamorphic sizes compared to those reared at low food levels. This suggests that the tadpoles prioritize rapid development at the expense of body mass during metamorphosis. Furthermore, our study discovered evidence supporting the positive effect of fecal material on tadpole growth, as indicated by the investigation of growth rate. Importantly, the presence of feces did not result in smaller body mass on average for Asiatic toad tadpoles compared to those raised in the absence of fecal material. The difference in body mass between fecal material treatments tended to be smaller at low food levels, implying that feces does not inhibit growth in B. gargarizans tadpoles. Therefore, our results contradict Richards’ hypothesis and provide support for a novel mechanism that is selected for in areas where coprophagy is likely to be advantageous, particularly in times of food scarcity.

Human health risk assessment of metal contamination in cereals and pulses in the mica mining areas of Jharkhand, India

This study was carried to investigate the contamination levels of heavy in food crops (rice, wheat, maize, and pulses) grown in the vicinity of the mica mine in Jharkhand, India. Except for Pb and Zn in select places, the metal concentrations in the food crops were below the maximum allowed levels for food in India. The principal component analysis identified three components that accounted for 71.3 % of the variability in the data. The components that were retrieved indicated that soil, irrigation water, and air dust deposition could be the sources of metals in the food crops. The estimated daily intake (EDI) and target hazard quotient (THQ) of food crop consumption were used to highlight the potential health concerns associated with metal exposure. In several samples, local individuals' daily intakes of Pb was greater than the WHO's recommended daily intakes of these heavy metals. Taking into account the geometric mean of metal concentrations in food crops samples from the, the hazard index (HI) for the consumers was 10.28 which is far above unity. Pb, Co, and As were the primary contributors to the potential non-carcinogenic risk. The HI ranged from 7.22 to 18.29 across different locations, indicating a significant health risk to the consumers of locally grown food crops in the vicinity of the mica mining areas.

Impacts of adaptation to climate change on farmers’ food security and level of sesame production in Western Ethiopia

The existence of multiple stresses and poor adaptive capacity make Africa most susceptible to climate change. In Ethiopia the potential adverse effects of climate change on the agricultural sector, the main stay of the country’s economy, are major concerns. To ensure food security, reducing the vulnerability of agricultural systems through different feasible adaptation strategies is one of the policy options in response to climate change impact This study is a first of its kind in examining the relative effectiveness of various adaptation strategies in ensuring farmers’ food security and enhancing level of sesame production in rural area of Western Ethiopia. In addition to data obtained from meteorological stations, cross-sectional data were collected interviewing 400 farm households. Descriptive statistics, two-stage least square (2SLS) and double-hurdle (D-H) models were used to analyze the data. The results of the study indicate that households are adapting using various strategies to the looming climate change in the area. The study also indicated that, though sesame production was negatively impacted by the climate hazards, smallholders have continued its production at minimum level due mainly to its high value crop character. 2SLS estimation results revealed that rainfall and temperature variability have negative impact on household’s food security. Moreover, the result indicates effectiveness of climate adaptation strategies namely agronomic practices, irrigation and soil and water conservation in reducing climatic risks and ensuring household food security. The result also implicitly indicated that farmers continued to adapt sesame production under risk climate and it is contributing to farmers’ food security. Further, the result revealed that climate change adaptation strategies have positively impacted the level of sesame production. Consequently, policy that augments households’ climate awareness and promotes adaptation decision and strategies could help reducing risks pertaining to climate and thereby improves farmers’ food security status and production of high value export potential crop—sesame.

The Effects of Ghrelin on Spike Activity of the Suprachiasmatic Nucleus Neurones of the Rat

In one of the most important non-photic mechanisms of the circadian biological clock synchronization with environmental geophysical 24 h rhythm, information on feeding schedule, composition and calorie content of food is used. Hormone ghrelin, a product of the neuroendocrine oxyntic cells of the gastric mucosa to be a signal molecule within this mechanism. In experiments on sagittal hypothalamic slices of male Wistar rats, the effects of 25 nM ghrelin on spike activity and parameters of spike information coding were investigated. Application of ghrelin induced an increase in spike frequency and a decrease in entropy of interspike interval distribution in 32.1% of the neurones recorded. In 29.6% of the cells, opposite responses in the form of a reduction of activity and an increase in the entropy of interspike interval distribution were observed. Parameters of spike activity of the reminder 38.3% neurones of the suprachiasmatic nucleus did not change. The observed responses of the entropy of interspike interval distribution indicate the appropriate changes in a degree of irregularity of interspike interval induced by ghrelin. Application of selective high-affinity antagonist of GHS-R1a receptor, JMV 2959 (100 nM) did not induce responses of the investigated parameters of spike activity but completely prevented changes of both, spike frequency and entropy of interspike interval distribution observed in the presence of ghrelin. The obtained data show that hormone ghrelin by a direct influence on the suprachiasmatic nucleus in vitro modulates the activity level and spike code of relatively numerous population of neurones of the nucleus, wherein the effects of ghrelin are implemented via GHS-R1a receptors. The results of the current study provide additional evidence in favour of the hypothesis on the involvement of ghrelin in mechanisms of non-photic entrainment of the circadian biological clock in accordance with severity of food motivation and level of metabolism.

Sustainable dairy farming and fipronil risk in circular feeds: insights from an Italian case study

Circular feeds, such as grain dry distillers, citrus pulp, cane molasses, and potatoes peels, are co-products of biomass processes. They are currently proposed in animal nutrition to improve the environmental and economic sustainability of the food production chain. In this paper, we report a case study involving fipronil, a pesticide currently not authorized for agriculture within the EU, but used in the Americas, Eastern Europe, and Asia. Fipronil was found at a mean level of 0.49 mg/kg, in a grain dry distiller batch administered to dairy cows. This finding, along with other evidence of potential fipronil presence in feed materials, prompted us to evaluate the risk to food safety and food security from 12 different conventional and sustainable feeding regimens. To this purpose, we considered a fipronil feed-to-milk carry-over rate of 0.52, the tolerance levels in fodders and food from The EU, Codex Alimentarius, and US-EPA, and the Acceptable Daily Intake (ADI) of 0.0002 mg/kg body weight for adverse effects on thyroid function in dairy cows. Under a conservative scenario, fipronil-contaminated potato peels and grain distillers in the feeding regimens may play a pivotal role in exceeding the EU Maximum Residue Level (MRL) in bovine milk and fat (0.005 and 0.030 mg/kg, respectively). Hay-based diets with soybean hulls and cane molasses show negligible risks (Hazard Index ∼ 1). In all cases, the ADI exceedance suggests the need to evaluate thyroid function in dairy cows exposed to fipronil as a food security factor.

Applying the internet of things (IoT) for raising black soldier Fly (BSF) in closed system to minimize greenhouse gas emissions

The Black Soldier Fly (BSF), scientifically known as Hermetia Illucens L., effectively reduces organic waste and decreases harmful gas emissions more efficiently than landfill or composting methods. However, it can still produce harmful gases during the rearing of BSF larvae, including carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and ammonia (NH3), which contribute directly and indirectly to the greenhouse effect. The pH level of the food provided to the larvae affects their biomass and leads to varying levels of gas emissions. This study aims to investigate the impact of greenhouse gas emissions when different pH levels of food are used, utilizing IoT technology to measure greenhouse gases and control the environmental conditions for rearing BSF larvae. The greenhouse gases monitored in this study include carbon dioxide (CO2) and methane (CH4), with environmental factors such as air temperature, humidity, soil moisture, and light intensity being controlled. The experiment tested pH levels ranging from 2.0, 4.0, 6.0, 7.0, and 8.0 to 10.0. The results show that different pH levels in food affect the emission of CO2 and CH4. Initially, a large amount of CO2 is released, gradually decreasing over time, while CH4 emissions steadily increase. In the early days, CH4 emissions are unstable, fluctuating before stabilizing. Food with a pH of 2.0 results in the lowest average CO2 emissions (430.53 PPM) from BSF larvae, and the lowest CH4 emissions (16.11 PPM) are also observed with a pH of 2.0.

Exploring the influence of refuges and additional foods on predator–prey interactions amidst environmental stochasticity and water level fluctuations

By considering that the predators have some additional foods apart from the focal prey and the prey take refuge, a predator–prey model with the effect of seasonality in a fluctuating environment is investigated in this study. Gaussian white noises, created by random fluctuation of water level, are introduced on the prey’s growth rate and predator’s mortality rate. Both the deterministic and stochastic systems are analyzed mathematically as well as numerically. Our analytical findings show that the intensity of environmental noise, additional foods and prey refuge play significant roles in survival as well as extinction of both prey and predator populations in the aquatic system. Our numerical results show that the effectual level of additional foods, depending on water level, has positive as well as negative effects on the predator and prey populations. We find that both species strongly persist at certain water level and for the low intensity of noise. However, for an increased value of noise intensity, they persist weakly and then go to extinction. Overall, our findings show that the variations of water level together with additional food and white noise plays crucial roles in persistence and extinction of species in the ecosystem.

Rapid and sensitive determination of bongkrekic acid with molecularly imprinted polymer-coated wooden-tip electrospray ionization mass spectrometry

In this study, a novel methodology has been developed for the rapid and sensitive analysis of bongkrekic acid (BA), a highly toxic bacterial metabolite, using a molecularly imprinted polymer-coated wooden-tip coupled with electrospray ionization mass spectrometry (MIPWT-ESI-MS). A MIPWT solid phase microextraction (SPME) probe specifically tailored for BA was fabricated, by employing dummy template molecules/functional monomers in the imprinting coating modification. This approach exhibits an enrichment factor (EF) of 683 ± 53 for efficient extraction of BA from aqueous matrices, demonstrating the utility of dummy templates in enhancing the selectivity and sensitivity of the MIPWT-ESI-MS method. The analytical performance of the MIPWT-ESI-MS method was evaluated, demonstrating a desirable linear correlation (r = 0.9988), along with remarkable sensitivity by a limit of detection (LOD) and limit of quantitation (LOQ) at 0.05 μg/L and 0.16 μg/L in pure water, respectively. Additionally, the method demonstrated high repeatability with a relative standard deviation (RSD) < 3.9 % (n = 6) and reproducibility with an RSD < 13.4 %. The practical application of the method was confirmed through the successful analysis of real-world samples, including tap water, wastewater from a food processing factory, and the aqueous extracts of food samples, with BA detected at 0.296 µg/L in Tremella. Spiking experiments further validated the accuracy of the method, with recoveries ranging from 81 % to 97 %. This study integrates MIP with ambient mass spectrometry, offering a robust, selective, and sensitive tool for the monitoring of trace BA levels in complex food and environmental samples, contributing significantly to public health safety and food quality control.