Current and Emerging Technologies for Rapid Detection of Pathogens

Foodborne diseases, caused by pathogenic bacteria, have become an important social issue in the field of food safety. It presents a widespread and growing threat to human health in both developed and developing countries. As such, techniques for the detection of foodborne pathogens and waterborne pathogens are urgently needed to prevent the occurrence of human foodborne infections. Although traditional culture-based bacterial isolation and identification are the “gold standard” methods with high preciseness, their drawbacks in time-consuming are inadequate for rapid detection of pathogen to reduce foodborne disease occurrence. Fortunately, with the development of biotechnologies and nanotechnologies, various kinds of new technologies for rapid detection of pathogens have been developed so far, such as nucleic acid-based methods, antibody-based methods, and aptamer-based assays. In this chapter, we summarized the principles and the application of some recent rapid detection technologies for pathogenic bacteria. Moreover, the advantages and disadvantages of the established and emerging rapid detection methods are addressed here

Ocjena brzog imunoenzimnog testa u otkrivanju onečišćenja mlijeka, vode i izmeta bakterijom Salmonella Typhimurium

Serology-based detection methods have more applicable characteristics than standard bacterial culture methods. The aim of this study was to evaluate a cost-efficient, rapid, sensitive and simple test to diagnose milk, water and feces contaminated with Salmonella enteric subsp. enterica serovar Typhimurium (S. Typhimurium). The method developed was based on the addition of HRP-conjugated anti-Salmonella antibodies to the sample, precipitation of the complexes formed using centrifuge, and evaluation of the peroxidase activity of the sample supernatants. Raw cow’s milk, water and cattle feces samples were spiked with seven concentrations of S. Typhimurium. The optimized test recorded an accurate volume and concentration of HRP-conjugated antibodies, the bacteria, samples, ionic compounds and the precise time of the reaction. Also, the method of the test and standard sample preparation were carefully optimized. The tests were repeated at least ten times, and the minimum level of detectable bacteria was determined for each repetition. The results obtained were compared with the conventional bacterial culture method. The results showed that in an optimal condition, conjugated anti-Salmonella antibodies interacted with the bacteria in any matrix. The developed method can detect at least 30, 30, 3×103, and 3×103 cell/mL of S. Typhimurium in water, PBS, milk and feces samples respectively, in less than 20 minutes. Also, antibody detection using this EIA can detect an antibody concentration range of 4.3-70 μg/mL. The developed method is a rapid, cost-efficient and simple assay, and can be used to detect S. Typhimurium in various samples.Serološke dijagnostičke metode znatno su primjenjivije u odnosu na standardne bakteriološke kulture. Cilj ovoga istraživanja bio je ocijeniti ekonomsku isplativost, brzinu, osjetljivost i jednostavnost testa u otkrivanju onečišćenosti mlijeka, vode i izmeta bakterijom Salmonella enteric subsp. enterica serovar Typhimurium (S. Typhimurium). Metoda se temelji na dodatku HRP-konjugiranih anti-Salmonella protutijela u uzorku, precipitaciji nastalih kompleksa centrifugom i procjeni peroksidazne aktivnosti supernatanta. Uzorci sirovog kravljeg mlijeka, vode i izmeta goveda inokulirani su sa sedam koncentracija bakterije S. Typhimurium. Primjenom optimiziranog testa zabilježeni su precizni podaci o volumenu i koncentraciji HRP-konjugiranih protutijela, bakterija, uzoraka, ionskih spojeva i vremenu reakcije. Test i priprema standardnih uzoraka pažljivo su optimizirani. Test je ponovljen najmanje deset puta i u svakom je ponavljanju određena najmanja razina detektibilnih bakterija te su rezultati uspoređeni s konvencionalnim pretragama kultura. Rezultati su pokazali da su u optimalnim uvjetima konjugirana anti-Salmonella protutijela reagirala s bakterijama u svakom tipu uzoraka. Razvijena metoda može u manje od 20 minuta otkriti barem 30 stanica/mL bakterije S. Typhimurium u vodi, 30 stanica/mL u PBS-u, 3×103 stanica/mL u mlijeku i 3×103 stanica/ mL u izmetu. Također, primjena ove metode mogla bi otkriti koncentraciju protutijela od 4,3 do 70 μg/mL. Metoda je brza, jeftina i jednostavna te može otkriti bakteriju S. Typhimurium u različitim uzorcima

Bioconjugated nanomaterials for monitoring food contamination

Maintaining food safety and hygiene standards is top priority and challenge for farmers, food industries, governments and food technologists working in the food supply chain. Pesticides, toxins, veterinary drug residues, foodborne pathogens and many other harmful chemicals that may be present in a vast array of food products, due to various stages of their production like packaging and transport, constitute a global health problem that requires powerful and innovative technologies allowing constant and accurate detection of food products from production to consumption. Recent progress in generation of specific synthetic oligonucleotides against food contaminants has provided a new insight into the current sensor technologies, where these functional synthetic oligonucleotides, so-called aptamers, have been successfully combined with nanomaterials for rapid and cost-effective detection of several substances related to the food contamination, such as antibiotics, mycotoxins, heavy metals, carcinogenic dyes, pesticides, pathogens and other plastic products used for food packaging. Unique characteristics of aptamers over antibodies, such as in vitro selection, chemical and thermal stability, small size and ease of labeling have laid the solid foundation for exploring aptamers further in multiplexed food monitoring systems. In this chapter, we reviewed the application of aptamer-conjugated nanomaterials in food safety surveillance as well as the conventional techniques used for food safety monitoring in order to provide a comprehensive and comparative approach

Biosensors: A Fast-Growing Technology for Pathogen Detection in Agriculture and Food Sector

Agriculture and food have a greater role to play in order to achieve sustainable development goals. Therefore, there is a need to put an end to the effect of pathogens on food quality and safety. Pathogens have been recognized as one of the major factors causing a reduction in profitable food production. The conventional methods of detecting pathogens are time-consuming and expensive for the farmers in rural areas. In view of this, this chapter reviews the biosensors that have been developed for the detection of biological hazards in food and agricultural sectors. This chapter also lays emphasis on the impact of nanotechnology on building a fast, reliable, more sensitive, accessible, user-friendly and easily adaptable technology for illiterate farmers in the rural communities. On the whole, we have addressed the past and most recent biosensors that could ensure the quick delivery of vision 2030 which aims to end hunger and poverty

Validity of a single antibody-based lateral flow immunoassay depending on graphene oxide for highly sensitive determination of E. coli O157:H7 in minced beef and river water

Considering the health risks of E. coli O157:H7 presence in food and water, an affordable and highly sensitive detection method is crucial. Herein, we report the first use of a single antibody-based fluorescent lateral flow immunoassay (FLFIA) depending on non-radiative energy transfer between graphene oxide and quantum dots for determination of E. coli O157:H7 in beef and river water. FLFIA showed a high sensitivity rate thousand-fold better than the conventional lateral flow (LF). In inoculated minced beef and river water samples, the limits of detection were 178 and 133 CFU g or mL, respectively. Besides, it presented a high selectivity in the presence of other possible interfering bacteria. The single antibody approach reduced the assay cost to 60% less than the conventional LF. Alongside, the results could be read by portable LF readers or smartphones. These advantages offer FLFIA as a promising technology for pathogen detection in food and water

Advanced biosensors for detection of pathogens related to livestock and poultry

Infectious animal diseases caused by pathogenic microorganisms such as bacteria and viruses threaten the health and well-being of wildlife, livestock, and human populations, limit productivity and increase significantly economic losses to each sector. The pathogen detection is an important step for the diagnostics, successful treatment of animal infection diseases and control management in farms and field conditions. Current techniques employed to diagnose pathogens in livestock and poultry include classical plate-based methods and conventional biochemical methods as enzyme-linked immunosorbent assays (ELISA). These methods are time-consuming and frequently incapable to distinguish between low and highly pathogenic strains. Molecular techniques such as polymerase chain reaction (PCR) and real time PCR (RT-PCR) have also been proposed to be used to diagnose and identify relevant infectious disease in animals. However these DNA-based methodologies need isolated genetic materials and sophisticated instruments, being not suitable for in field analysis. Consequently, there is strong interest for developing new swift point-of-care biosensing systems for early detection of animal diseases with high sensitivity and specificity. In this review, we provide an overview of the innovative biosensing systems that can be applied for livestock pathogen detection. Different sensing strategies based on DNA receptors, glycan, aptamers and antibodies are presented. Besides devices still at development level some are validated according to standards of the World Organization for Animal Health and are commercially available. Especially, paper-based platforms proposed as an affordable, rapid and easy to perform sensing systems for implementation in field condition are included in this review

A review on urinary tract infections diagnostic methods: Laboratory-based and point-of-care approaches

Urinary tract infections (UTIs) are among the most common infectious diseases worldwide. This type of infections can be healthcare-associated or community-acquired and affects millions of people every year. Different diagnostic procedures are available to detect pathogens in urine and they can be divided into two main categories: laboratory-based and point-of-care (POC) detection techniques. Traditional methodologies are often timeconsuming, thus, achieving a rapid and accurate identification of pathogens is a challenging feature that has been pursued by many research groups and companies operating in this area. The purpose of this review is to compare and highlight advantages and disadvantages of the traditional and currently most used detection methods, as well as the emerging POC approaches and the relevant advances in on-site detection of pathogens ' mechanisms, suitable to be adapted to UTI diagnosis. Lately, the commercially available UTI self-testing kits and devices are helping in the diagnosis of urinary infections as patients or care givers are able to perform the test, easily and comfortably at home and, upon the result, decide when to attend an appointment/Urgent Health Care Unit.info:eu-repo/semantics/publishedVersio

New Insight into Brucella Infection and Foodborne Diseases

Brucellosis is an important zoonotic disease. More than half a million new cases from 100 countries are reported annually to the World Health Organization (WHO). The majority of patients are living in developing countries. Brucellosis is a systemic infection with a broad clinical spectrum, ranging from an asymptomatic disease to a severe and fatal illness. Clinical and laboratory features vary widely. The main presentations are acute febrile illness, localized infection, and chronic infection. Laboratory tools for diagnosis of brucellosis include culture, serology, and polymerase chain reaction (PCR). The goal of brucellosis therapy is to control the illness and prevent complications, relapses, and sequelae. Important principles of brucellosis treatment include use of antibiotics with activity in the acidic intracellular environment, use of combination regimens, and prolonged duration of treatment. This book is the result of several months of outstanding efforts by the authors and the revision of the content by experts in the field of brucellosis. This book is a valid resource and is intended for everyone interested in infectious disease to learn the most important aspects of brucellosis