scholarly journals Generating new mixtures of food additives with antimicrobial and cytotoxic potency against Bacillus cereus and Staphylococcus aureus

2022 ◽  
Author(s):  
Samy Selim ◽  
Mohammed S. Almuhayawi ◽  
Mohammed H. Alruhaili ◽  
Shadi A. Zakai ◽  
Mona Warrad
2020 ◽  
Vol 83 (8) ◽  
pp. 1302-1306
Author(s):  
EUN-SEON LEE ◽  
JONG-HUI KIM ◽  
MI-HWA OH

ABSTRACT In dairy plants, clean-in-place (CIP) equipment cannot be disassembled, making it difficult to clean the inner surface of pipes. In this study, the inhibitory effects of chemical agents on biofilms formed by three foodborne pathogens, Bacillus cereus, Escherichia coli, and Staphylococcus aureus, was evaluated in a dairy CIP system. The experiment was conducted on a laboratory scale. Each of the three bacteria (200 μL) was inoculated onto stainless steel (SS) chips (25 by 25 mm), and the effect of single cleaning agents was evaluated. Individual treatments with NaClO (30, 50, 100, and 200 ppm), NaOH (0.005, 0.01, 0.05, and 0.1%), citric acid (1, 3, 5, and 7%), and nisin (5, 10, 25, 50, 100, and 200 ppm) were used to clean the SS chip for 10 min. The most effective concentration of each solution was selected for further testing in a commercial plant. Simultaneous cleaning with 200 ppm of NaClO (10 min) and 7% citric acid (10 min) reduced the biofilms of B. cereus, E. coli, and S. aureus by 6.9, 7.0, and 8.0 log CFU/cm2, respectively. Both 7% citric acid and 0.1% NaOH were optimal treatments for E. coli. NaClO and citric acid are approved for use as food additives in the Republic of Korea. Our results revealed that a combined treatment with NaClO and citric acid is the most effective approach for reducing biofilms formed by common foodborne pathogens on CIP equipment. These findings can contribute to the production of safe dairy products. HIGHLIGHTS


Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 36
Author(s):  
Carla Gonçalves ◽  
Ana Gomes ◽  
Alexandra Esteves ◽  
José António Silva ◽  
Cristina Maria Saraiva

The present study aims to contribute to sustainable development goals by increasing knowledge of food safety and food waste of meals produced by the cook–chill system in hospital units. The food waste (FW) of meals served at lunch was evaluated for all new hospitalized patients with light diet (n = 17) and soft texture diet (n = 10), during their hospital stay, using the physical method by weighing for dish and the visual estimation method for the soup. Samples of each diet (light, n = 3; soft texture, n = 3) were also collected in four different moments (after cooked, after cold transportation, after refrigerated storage and after hot regeneration) for detection and enumeration of Listeria monocytogenes, Salmonella spp. and Staphylococcus aureus and enumeration of Escherichia coli, Clostridium spp., Bacillus cereus, Enterobacteriaceae, total viable counts (TVC) at 30 °C, as well as pH, water activity, moisture, ashes and protein. The FW (%) of the light diet (n = 64) was 39.8 ± 6.3 in dish and 14.9 ± 5.4 in soup, and of the soft texture diet (n = 51) was 65.1 ± 9.0 in dish and 39.0 ± 5.8 in soup. Regarding the percentage of protein per meal, both light (8.73%) and soft (3.33%) diets presented on average values lower than those recommended by the WHO (10–15% protein). The value of different microorganisms varied along the production moments; however, the final products in the light diet (after hot regeneration) presented 1.34–1.73 log cfu/g of TVC. Counts of Bacillus cereus and Staphylococcus aureus were also obtained at low levels (less than 1 log cfu/g). Besides these results, the risk of foodborne diseases should be considered. The implementation of effective measures to increase food safety and reduce FW in hospital is crucial.


1970 ◽  
Vol 18 ◽  
pp. 16-20
Author(s):  
BA Omogbai ◽  
FA Eze

Context: Plant based antimicrobial represent a vast untapped source for medicines and further exploration of plant antimicrobial neeto occur. Evolvulus alsinoides (L) (Convolvulaceae) is a perennial herb is used in traditional medicine in East Asia, India, Africa and Philippines to cure fever, cough, cold, venereal diseases, azoospermia, adenitis and dementia.   Objective: The objective of this research was to evaluate the antimicrobial activity of the extracts of E. alsinoides on some clinical microbial isolates.   Materials and Methods: The ed thanolic and aqueous extracts of the whole plant (leaves and twigs) were analysed for alkanoids, tannins, glycosides, steroids, flavonoids, saponins, volatile oil and resins. The determination of antibacterial activity was done using the agar well diffusion technique. Pure cultures of pathogenic bacteria such as Bacillus cereus, Staphylococcus aureus, Micrococcus leutus, Klebsiella Pneumoniae, Pseudomonas aeruginosa, Escherichia coli and Salmonella typhi were used for antibacterial activity assay, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC).   Results: The ethanolic extract of the plant had MIC values ranging from 16 mg/ml to 512.5 mg/ml. The least MIC was 16mg-ml against Salmonella typhi while Bacillus cereus and Staphylococcus aureus showed the highest MIC of 512.5 mg-ml. In the aqueous extract the MIC ranged between 512.5 to >1025 mg/ml. Salmonella typhi, Micrococcus luteus and Staphylococcus aureus were not inhibited by the water extract. Phytochemical result showed ethanol to be a better solvent for the extraction of the bioactive agents in this plant which include: glycosides, alkaloids, saponins, tannins, flavonoids and volatile oil.   Conclusion: In this study the gram-negative organisms had the lowest MICs and MBCs. This suggests their higher susceptibility to the extract of this plant. On the basis of the result obtained in this investigation it can be concluded that ethanol extract of Evolvulus alsinoides had significant in vitro broad spectrum antimicrobial activity.   Keywords: Evolvulus alsinoides; Phytochemical screening; Antibacterial activity. DOI: http://dx.doi.org/10.3329/jbs.v18i0.8769 JBS 2010; 18(0): 16-20


1979 ◽  
Vol 42 (6) ◽  
pp. 464-469 ◽  
Author(s):  
M. E. STILES ◽  
L.-K. NG

Ham and chopped ham from two manufacturers were contaminated with five enteropathogens: Bacillus cereus, Clostridium perfringens, Escherichia coli, Salmonella typhimurium and Staphylococcus aureus, at time of slicing and vacuum-packaging, to simulate contamination by manufacturer. Subsequent treatment of the samples, representing sound and undesirable retail handling and consumer use conditions, indicated marked differences in the fate of the pathogens between these products and within product type between the two manufacturers. Greatest differences were observed between the chopped ham products. All pathogens, except C. perfringens, grew actively in fresh ham and chopped ham with abusive holding at 30 and 21 C. After storage at 4 or 10 C for 30 days, B. cereus and C. perfringens were no longer detected, even after subsequent holding at 30 or 21 C for 24 h. E. coli survival and growth was variable, S. typhimurium survived well and grew under some conditions and S. aureus was generally inhibited at high levels of competition.


2008 ◽  
Vol 71 (2) ◽  
pp. 325-332 ◽  
Author(s):  
YONG-SUK KIM ◽  
ZIAN-BIN ZHENG ◽  
DONG-HWA SHIN

Kimchi is a unique Korean traditional vegetable product that is fermented by lactic acid bacteria (LAB) and is mainly consumed as a side dish with boiled rice. Its main ingredients are brined Chinese cabbage, red pepper powder, and fermented fish sauce, and these are combined with many spices such as garlic, green onion, ginger, and some seaweed. The relationship between the concentration of LAB or the pH and the growth of three gram-positive foodborne pathogens (Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus) was evaluated. Heat treatment (HT; 85°C for 15 min) or neutralization treatment (NT; pH 7.0) was conducted on day 0 (0-D group) and day 3 (3-D group) of incubation. The pH in the control group and the NT group dropped sharply to 4.12 to 4.30 after 2 days of incubation and slightly decreased thereafter, whereas the pH in the control group and HT group stayed at 7.0 during incubation. LAB were not detected in the HT kimchi during incubation. B. cereus in the NT-0-D, NT-3-D, and HT-3-D groups was reduced by 1.5 to 3.1 log CFU/ml but increased slightly in the HT-0-D group. L. monocytogenes in HT-3-D and NT-3-D groups disappeared after 5 days of incubation, and S. aureus in the NT-0-D group disappeared after 4 days. These findings indicate that growth of all the foodborne pathogens was inhibited by NT-0-D, HT-3-D, and NT-3-D, but B. cereus was not inhibited by HT-0-D. Thus, growth of LAB in kimchi is an important factor in the control of foodborne pathogens.


1969 ◽  
Vol 43 (4) ◽  
pp. 278-290
Author(s):  
Lilybett Valentín-Ramos

A study was undertaken for the purpose of obtaining information about the flora normally encountered in sweetpotatoes and fresh guavas. Homogeneous suspensions of the cortex and flesh of both products were prepared in sterile water and used for the isolation of micro-organisms. Isolations were carried out on Tryptone Glucose Extract Agar plates incubated at 27°, 37°, and 55° C. An extensive study of the morphological and physiological characteristics of each micro-organism was carried out in accordance with the 7th edition of the Bergey's Manual of Determinative Bacteriology (1957). It was found that the organisms isolated from sweetpotatoes are similar to the Genera Bacillus cereus and B. lichemformis. Those isolated from guava were classified as Bacillus megatherium; B. cereus; B. pumilus; B. subtilis var. niger; and Staphylococcus aureus.


2019 ◽  
Vol 12 (2) ◽  
Author(s):  
Gino Nemesio Cepeda ◽  
Meike Meilan Lisangan ◽  
Isak Silamba ◽  
Nitia Nilawati ◽  
Eka Syartika

ABSTRACT  Akway (Drimys piperita) is a woody, evergreen and aromatic plant that belongs to family winteraceae. This plant is used by Sougb tribe lived in Sururey village, District of Anggi, to enhance the vitality of body. The objectives of the research were to determine antimicrobial stability of akway bark extracts influenced by heating time of 100OC, levels of acidity (pH) and salt contents.. Antimicrobial assays were done by using agar well diffusion method against four species of bacteria, i.e.  Escherichia coli ATCC25922, Bacillus cereus ATCC10876, Pseudomonas aeruginosa ATCC27853 and Staphylococcus aureus ATCC25923. The results showed that ethanolic extracts of akway bark only inhibited growth of B. cereus and S. aureus with minimum inhibitory concentration 0,99% and 0,89% . The levels of concentration and acidity of ethanol extracts  influenced the antimicrobial capacity of extracts.. Whereas heating time on 100OC during 25 minutes and salt contents  up to 5% of extract solution did not influence the antimicrobial stability of  akway bark extracts. Key words : akway, extracts, antimicrobe, pH, Heating, salt ABSTRAK Akway (Drimys piperita) adalah tumbuhan berkayu, aromatik dan hijau sepanjang tahun dan tergolong dalam suku winteraceae. Tumbuhan ini digunakan oleh Suku Sougb yang bermukim di desa Sururey Distrik Anggi, untuk mengobati malaria dan meningkatkan vitalitas tubuh. Tujuan dari penelitian ini adalah untuk menentukan stabilitas antimikroba ekstrak kulit kayu akway pada waktu pemanasan ekstrak pada 100OC, tingkat keasaman (pH) dan kandungan garam. Pengujian antimikroba dilakukan dengan menggunakan metode difusi agar terhadap empat spesies bakteri yaitu Escherichia coli ATCC25922, Bacillus cereus ATCC10876, Pseudomonas aeruginosa ATCC27853 and Staphylococcus aureus ATCC25923. Hasil menunjukkan bahwa ekstrak etanol kulit kayu akway hanya dapat menghambat bakteri Bacillus cereus dan Staphylococcus aureus dengan konsentrasi hambat minimum masing-masing adalah 0,99% dan 0,89%. Tingkat konsentrasi dan keasaman (pH) mempengaruhi kapasitas antimikroba ekstrak etanol kulit kayu akway. Sedangkan perlakuan pemanasan pada suhu 100OC dengan lama pemanasan sampai dengan 25 menit dan penambahan garam NaCl sampai konsentrasi 5%  tidak berpengaruh pada stabilitas antimikroba ekstrak etanol kulit kayu akway.  


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