Research Publications (Food Safety)

The medicinal plants, like Alhagi maurorum, has received great attentions, especially by food scientists and manufacturers as natural food preservatives due to their antimicrobial and antioxidant activities.

Bacillus cereus is one of the important foodborne pathogens that can be found in various foodstuffs; causing diarrheal and/or emetic syndromes. This study aimed to evaluate the prevalence, antimicrobial susceptibility profile, pathogenic potential, and genotypic diversity of B. cereus isolated from diverse food products from markets in Cairo, Egypt. A total of 39 out of 165 food samples were positive for B.

The antibacterial effect of volatile compounds in millets and cereal by‐products was investigated. Hexane extracts of rice bran (RB), corn cob (CC), green (GM), and yellow millets (YM) showed antibacterial activities against Escherichia coli ATCC 35150, Bacillus cereus ATCC 14579, Helicobacter pylori MH179991, and Staphylococcus aureus ATCC 13150 with minimum inhibitory concentration (MIC) ranging from 2.5 to 5 mg/ml.

Members of the Bacillus cereus group are spore-forming organisms commonly associated with food poisoning and intestinal infections. Moreover, some strains of the group (i.e., B. cereus sensu stricto and Bacillus thuringiensis) can cause bacteremia in humans, mainly in immunocompromised individuals. Here we performed the genetic characterization of 17 human clinical strains belonging to B. cereus group isolated from blood culture.

The lesser-known traditionally processed meat products such as beef kargyong, pork kargyong, satchu, and khyopeh are popular food items in the Himalayan state of Sikkim in India. The present study aimed to assess the microbiological safety of traditional meat products by identifying the potential spoilage or pathogenic bacteria, detecting the enterotoxins, and screening the antibiotic susceptibility patterns.

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The presence of Bacillus cereus plays a key role in clubroot suppression and improves plant biomass in pak choi. B. cereus is reported for the first time as a novel biocontrol agent against clubroot.

Author(s): Yiying Huang, Steve H. Flint, Shubo Yu, Yu Ding, Jon S. Palmer

Avocado Hass (Persea americana Mill) peel extract (APE) has the potential as a natural ingredient to substitute for chemical preservatives.

Author(s): Hui Guo, Pengfei Yu, Shubo Yu, Juan Wang, Junhui Zhang, Ying Zhang, Xiyu Liao, Shi Wu, Qinghua Ye, Xiaojuan Yang, Tao Lei, Haiyan Zeng, Rui Pang, Jumei Zhang, Qingping Wu, Yu Ding

Flagellar motility is considered an important virulence factor in different pathogenic bacteria. In Listeria monocytogenes the transcriptional repressor MogR regulates motility in a temperature-dependent manner, directly repressing flagellar- and chemotaxis genes. The only other bacteria known to carry a mogR homolog are members of the Bacillus cereus group, which includes motile species such as B.

Bacillus cereus is the fourth most common cause of foodborne illnesses that produces a variety of pore-forming proteins as the main pathogenic factors. B. cereus hemolysin II (HlyII), belonging to pore-forming β-barrel toxins, has a C-terminal extension of 94 amino acid residues designated as HlyIICTD. An analysis of a panel of monoclonal antibodies to the recombinant HlyIICTD protein revealed the ability of the antibody HlyIIC-20 to inhibit HlyII hemolysis.

Bacteria survive metal stress by several mechanisms and metal binding is one such mechanism which has been screened in the present study to investigate the survival strategies of metal resistant bacteria. The production of siderophores, a metal chelating agent, was detected by chrome azurol S agar assay. The changes in cell wall studied by analyzing the peptidoglycan and teichoic acid content indicated an increase in the cell wall content.

Production and world consumption of spices are constantly increasing. Although the antimicrobial properties of some spices are well documented, their use in the agri‐food industry is also responsible for microbial contamination and spoilage. Bacterial spores introduced by spices can withstand different preparation processes, particularly thermal treatments, leading to food alterations during storage.

Bacteriophage endolysins have attracted attention as promising alternatives to antibiotics, and their modular structure facilitates endolysin engineering to develop novel endolysins with enhanced versatility. Here, we constructed hybrid proteins consisting of two different endolysins for simultaneous control of two critical foodborne pathogens, Staphylococcus aureus and Bacillus cereus. The full-length or enzymatically active domain (EAD) of LysB4, an endolysin from the B.

Native egg albumin (NEA) was isolated from hen eggs and hydrolyzed by pepsin to produce hydrolyzed egg albumin (HEA). HEA was chemically characterized and screened for its antibacterial activity against 10 pathogenic bacteria (6 Gram (+) and 4 Gram (−)). The SDS-PAGE pattern of NEA showed molecular weights of hen egg albumin subunits ranging from 30 to 180 kDa. The highest intensive bands appeared at a molecular mass of about 50 and 97 kDa.

Cysteine is a semiessential amino acid and plays an important role in metabolism and protein structure and has also been applied in various industrial fields, such as pharmaceutical, food, cosmetic, and animal feed industries. Metabolic engineering studies have been conducted for the cysteine production through bacterial fermentation, but studies on the cysteine biosynthetic pathway in microorganisms are limited.

This study aimed at evaluating the effects of a probiotic additive in productive performance and physiological parameters for Rhamdia quelen. The fish were fed diets containing increasing levels of the additive (0.15; 0.30; 0.45; and 0.60 g/kg of feed), which consisted of a blend of Bacillus cereus and B. subtilis, both at the concentration of 4 × 1011 CFU). Productive performance parameters were higher in fish fed diets containing 0.60 g/kg of the probiotics.

In this study, a new vancomycin (Van)-modified poly-l-lysine (PLL) magnetic bead (MB) technique was developed for isolation of gram-positive bacteria. The method combines magnetic separation with a multiplex PCR (mPCR) assay and gel electrophoresis for easy and rapid detection of Bacillus cereus. Vancomycin was used as a molecular ligand between the MB and the d-alanyl-d-alanine moieties on the cell wall surface of B. cereus.

by Anna V. Skorynina, Emma G. Piligrimova, Olesya A. Kazantseva, Vladislav A. Kulyabin, Svetlana D. Baicher, Natalya A. Ryabova, Andrey M. Shadrin

Antibiotic misuse is a public health problem due to the appearance of resistant strains in almost all human pathogens, making infectious diseases more difficult to treat. The search for solutions requires the development of new antimicrobials as well as novel strategies, including increasing social awareness of the problem.

The aim of this research was to examine bacteriological quality of some ready-to-eat foods that were served in some food centres in Zaria. Samples of jollof rice, pounded yam and melon seed soup were collected from three categories of food service centres and enumerated on selective media for the isolation of Bacillus cereus, Escherichia coli and Staphylococcus aureus.

Bacillus cereus sensu lato strains (B. cereus group) are widely distributed in nature and have received interest for decades due to their importance in insect pest management, food production and their positive and negative repercussions in human health. Consideration of practical uses such as virulence, physiology, morphology, or ill-defined features have been applied to describe and classify species of the group.

As a multifactorial cause, gastric ulceration-mediated diarrhea is widely prevalent in the weaned piglets, impairing pig health and economic benefits. With full implementation of antibiotic stewardship programs in China, Bacillus cereus (B. cereus) and Aspergillus fumigatus (A. fumigatus) were identified frequently in porcine feedstuffs and feeds of the animal industry. Association between feed-borne B. cereus and frequent diarrhea remains unclear.

The ubiquitous soil bacterium Bacillus cereus presents major challenges to food safety. It is responsible for two types of food poisoning, the emetic form due to food intoxication and the diarrheal form emerging from food infections with enteropathogenic strains, also known as toxico-infections, which are the subject of this review. The diarrheal type of food poisoning emerges after production of enterotoxins by viable bacteria in the human intestine.

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