The antibiotic resistome in Escherichia coli isolated from human, food, and animal sources

AIMS

The aim of this study was to analyze and compare the prevalence and distribution of resistance genes in Escherichia coli genomes isolated from human clinical samples and animal-based foods worldwide.

METHODS AND RESULTS

We download from NCBI Pathogen Detection Database the corresponding metadata of the 7,123 E. coli genome to access the information about the antimicrobial resistance gene content. The geographic location and the source of isolation were also obtained and compiled with the antimicrobial resistance gene for statistical analysis, results and discussion. Our criteria considered four groups for analyzing the antimicrobial resistance gene distribution. The first group of genomes from invasive clinical human (ICH) samples from countries with Human Development Index (HDI) ≥ 0.850; the second group of ICH from countries with an HDI ≤ 0.849; the third group of animal-based foods (ABF) from countries with HDI ≥ 0.850 and the fourth group of ABFs from countries with HDI ≤ 0.849. The most prevalent genes in the first group were blaCTX-M-134 (96.53%) and blaCTX-M-27 (86.35%). In the second group, ere(A) (95.96%), soxS (94.49%), qepA8 (90.81%), blaCTX-M-15 (85.66%), and fosA3 (80.88%). In the third group, the most frequently detected were aadA12 (98.5%), ant(3") (89.92%), and blaCARB-2 (87.2%). In the fourth group, aadA12 and aac(3)-IV were identified in 100% of the analyzed genomes.

CONCLUSIONS

It was clear that the use of aminoglycosides in animal production is increasing the selective pressure on micro-organisms in both groups of countries since genes linked to aminoglycoside resistance are related to E. coli from ABF samples. The genomic profile of E. coli from HDI ≥ 0.850 countries indicates a selective pressure aimed at cephalosporins given the high prevalence in both sources.

Behavioral Characteristics and Self-Reported Health Status among 2029 Adults Consuming a "Carnivore Diet"

BACKGROUND

The "carnivore diet," based on animal foods and excluding most or all plant foods, has attracted recent popular attention. However, little is known about the health effects and tolerability of this diet, and concerns for nutrient deficiencies and cardiovascular disease risk have been raised.

OBJECTIVES

We obtained descriptive data on the nutritional practices and health status of a large group of carnivore diet consumers.

METHODS

A social media survey was conducted 30 March-24 June, 2020 among adults self-identifying as consuming a carnivore diet for ≥6 mo. Survey questions interrogated motivation, dietary intake patterns, symptoms suggestive of nutritional deficiencies or other adverse effects, satisfaction, prior and current health conditions, anthropometrics, and laboratory data.

RESULTS

A total of 2029 respondents (median age: 44 y, 67% male) reported consuming a carnivore diet for 14 mo (IQR: 9-20 mo), motivated primarily by health reasons (93%). Red meat consumption was reported as daily or more often by 85%. Under 10% reported consuming vegetables, fruits, or grains more often than monthly, and 37% denied vitamin supplement use. Prevalence of adverse symptoms was low (<1% to 5.5%). Symptoms included gastrointestinal (3.1%-5.5%), muscular (0.3%-4.0%), and dermatologic (0.1%-1.9%). Participants reported high levels of satisfaction and improvements in overall health (95%), well-being (66%-91%), various medical conditions (48%-98%), and median [IQR] BMI (in kg/m2) (from 27.2 [23.5-31.9] to 24.3 [22.1-27.0]). Among a subset reporting current lipids, LDL-cholesterol was markedly elevated (172 mg/dL), whereas HDL-cholesterol (68 mg/dL) and triglycerides (68 mg/dL) were optimal. Participants with diabetes reported benefits including reductions in median [IQR] BMI (4.3 [1.4-7.2]), glycated hemoglobin (0.4% [0%-1.7%]), and diabetes medication use (84%-100%).

CONCLUSIONS

Contrary to common expectations, adults consuming a carnivore diet experienced few adverse effects and instead reported health benefits and high satisfaction. Cardiovascular disease risk factors were variably affected. The generalizability of these findings and the long-term effects of this dietary pattern require further study.

Development of a Food Composition Database for Assessing Nitrate and Nitrite Intake from Animal-based Foods

Scope

Nitrate and nitrite are approved food additives in some animal‐based food products. However, nitrate and nitrite in foods are strictly regulated due to health concerns over methaemoglobinaemia and the potential formation of carcinogenic nitrosamines. In contrast, plants (like leafy vegetables) naturally accumulate nitrate ions; a growing body of research reveals beneficial metabolic effects of nitrate via its endogenous conversion to nitric oxide. To refine the association of dietary nitrate and nitrite intake with health outcomes, reliable measures of nitrate and nitrite intake from dietary food records are required. While a vegetable nitrate content database has been developed, there is a need for a comprehensive up‐to‐date nitrate and nitrite content database of animal‐based foods.

Methods and Results

A systematic literature search (1980–September 2020) on the nitrate and nitrite content of animal‐based foods is carried out. Nitrate and nitrite concentration data and other relevant information are extracted and compiled into a database. The database contains 1921 entries for nitrate and 2077 for nitrite, extracted from 193 publications. The highest median nitrate content is observed in chorizo (median [IQR]; 101.61 [60.05–105.93] mg kg^‐1). Canned fish products have the highest median nitrite level (median [IQR]; 20.32 [6.16–30.16] mg kg^‐1). By subgroup, the median nitrate value in industrial processed meat products (e.g., uncured burger, patties and sausages), whole milk powder and in particular red meat are higher than cured meat products. Processed meat products from high‐income regions have lower median nitrate and nitrite content than those of middle‐income regions.

Conclusion

This database can now be used to investigate the associations between nitrate and nitrite dietary intake and health outcomes in clinical trials and observational studies.

Knowledge on the Complementary Feeding of Infants Older than Six Months among Mothers Following Vegetarian and Traditional Diets

Solid foods should be introduced not later than the age of six months, regardless of whether the family adheres to a traditional, vegetarian, or vegan diet. The aim of this study was to compare the knowledge on the complementary feeding of infants older than six months among mothers who adhere to traditional and vegetarian diets and to identify problems that require the assistance of a dietician. A total of 251 mothers of children aged 10–12 months participated in the study. Only 10% of vegetarian mothers declared that they had placed their children on a vegetarian diet, whereas 36 mothers adhered to a lacto-ovo-vegetarian diet during complementary feeding in the first year of life. Mothers adhering to a traditional diet were characterized by lower levels of knowledge (4.1 ± 2.3 points) than vegetarian mothers (5.3 ± 2.1 points). Mothers following a traditional diet were more likely to indicate a higher than recommended number of daily meals (OR = 1.76; Cl: 1.31–1.97, p < 0.001). Significant differences were noted in the respondents’ adherence to the BLW method, which was more readily implemented by vegan (p < 0.05) and lacto-vegetarian (p < 0.05) mothers and was least popular among mothers following a traditional diet (OR = 0.81; CI: 0.66–1.23, p < 0.04). Vegetarian mothers unnecessarily delayed the introduction of gluten and potentially allergizing foods to the children’s diets, sometimes even past the age of 12 months.

The Applicability of Essential Oils in Different Stages of Production of Animal-Based Foods

Essential oils (EOs) have been used for centuries, and interest in these compounds has been revived in recent years. Due to their unique chemical composition as well as antimicrobial, immunostimulatory, anti-inflammatory and antioxidant properties, EOs are used in pharmacology, cosmetology and, increasingly, in animal breeding and rearing, and processing of animal raw materials. Essential oils have become a natural alternative to preservatives, taste enhancers and, most importantly, antibiotics, because the European Union banned the use of antibiotics in metaphylaxis in animal husbandry in 2006. In the animal production chain, EOs are used mainly as feed additives to improve feed palatability and increase feed intake, improve animal resistance and health status, and to prevent and treat diseases. Recent research indicates that EOs can also be applied to sanitize poultry houses, and they can be used as biopesticides in organic farming. Essential oils effectively preserve meat and milk and, consequently, improve the safety, hygiene and quality of animal-based foods. Novel technologies such as encapsulation may increase the bioavailability of EOs and their application in the production of food and feed additives.

Fabrication of Curcumin-Loaded Dairy Milks Using the pH-Shift Method: Formation, Stability, and Bioaccessibility

The pH-shift method is a simple approach for incorporating certain kinds of polyphenol-based nutraceuticals into already existing colloidal systems. The polyphenols can be loaded into hydrophobic particles due to the fact that their water-solubility is relatively high under alkaline conditions but low under acid or neutral conditions. In this study, it was demonstrated that bovine milk could be enriched with curcumin using this approach, without adversely affecting milk fat globule stability. The storage stability of the curcumin-enriched bovine milk was assessed when samples were incubated for 60 days at different pH values and temperatures. The pH-stability was determined by storing curcumin-enriched milk at 4 °C for 60 days at pH 6.5, 7.0, and/or 8.0. At this low storage temperature, all milk samples were stable to fat globule aggregation, creaming, curcumin degradation (<13% loss), and color loss. The temperature-stability was determined by storing curcumin-enriched milk at pH 7 for 15 days at 4, 20, 37, or 55 °C. Curcumin breakdown decreased with decreasing storage temperature: 55 °C (43%) > 37 °C (21%) > 20 °C (10%) > 4 °C (5%). Interestingly, the color of the curcumin-enriched milks incubated at 4, 20, and 37 °C remained similar to that of the initial samples, but the sample stored at 55 °C showed significant color fading. Curcumin bioaccessibility determined using an in vitro gastrointestinal tract was around 40%, which was attributed to some chemical degradation and binding of the curcumin reducing its stability and solubilization. This study shows that a hydrophobic nutraceutical (curcumin) can be loaded into dairy milk products using a simple method, which could facilitate the creation of novel functional foods and beverages.

Barriers to and Facilitators of the Consumption of Animal-Based Protein-Rich Foods in Older Adults

Protein intakes in the older population can be lower than recommended for good health, and while reasons for low protein intakes can be provided, little work has attempted to investigate these reasons in relation to actual intakes, and so identify those of likely greatest impact when designing interventions. Questionnaires assessing: usual consumption of meat, fish, eggs and dairy products; agreement/disagreement with reasons for the consumption/non-consumption of these foods; and several demographic and lifestyle characteristics; were sent to 1000 UK community-dwelling adults aged 65 years and over. In total, 351 returned questionnaires, representative of the UK older population for gender and age, were suitable for analysis. Different factors were important for consumption of the four food groups, but similarities were also found. These similarities likely reflect issues of particular concern to both the consumption of animal-based protein-rich foods and the consumption of these foods by older adults. Taken together, these findings suggest intakes to be explained by, and thus that strategies for increasing consumption should focus on: increasing liking/tastiness; improving convenience and the effort required for food preparation and consumption; minimizing spoilage and wastage; and improving perceptions of affordability or value for money; freshness; and the healthiness of protein-rich foods.