The occurrence of antibiotic residues in milk constitutes a potential risk to the health of consumers. The present study describes the optimisation and validation of a high-performance liquid ...chromatographic (HPLC) method for the simultaneous determination of sulphadiazine (SDZ), sulphamethoxazole (SMX), oxytetracycline (OTC), doxycycline (DOX), tetracycline (TC), enrofloxacin (ENRO) and chloramphenicol (CLP) residues in bovine milk using colchicine (COL) as internal standard. The determination of these antimicrobials was carried out on C
18
analytical column using high-performance liquid chromatographic-diode array detection (HPLC-DAD). The extraction method involving deproteinisation of the milk sample followed by a solid-phase extraction (SPE) clean-up of antibiotic residues has been developed. The method was validated according to the European Commission Decision 2002/657/EC and applied for the analysis of antibiotic residues in 21 raw milk samples collected from Ludhiana, Punjab, India. The recoveries for the studied antibiotics ranged from 83.3–111.8% with relative standard deviations between 3.5 and 16.2%. The limits of quantification for these antibiotics, with the exception of chloramphenicol, were below the maximum residue limits (MRLs), making the method suitable for performing routine analysis.
Biofilms pose a serious public health hazard with a significant economic impact on the food industry. The present scoping review is designed to analyse the literature published during 2001–2020 on ...biofilm formation of microbes, their detection methods, and association with antimicrobial resistance (if any). The peer‐reviewed articles retrieved from 04 electronic databases were assessed using PRISMA‐ScR guidelines. From the 978 preliminary search results, a total of 88 publications were included in the study. On analysis, the commonly isolated pathogens were Listeria monocytogenes, Staphylococcus aureus, Salmonella spp., Escherichia coli, Bacillus spp., Vibrio spp., Campylobacter jejuni and Clostridium perfringens. The biofilm‐forming ability of microbes was found to be influenced by various factors such as attachment surfaces, temperature, presence of other species, nutrient availability etc. A total of 18 studies characterized the biofilm‐forming genes, particularly for S. aureus, Salmonella spp., and E. coli. In most studies, polystyrene plate and/or stainless‐steel coupons were used for biofilm formation, and the detection was carried out by crystal violet assays and/or by plate counting method. The strain‐specific significant differences in biofilm formation were observed in many studies, and few studies carried out analysis of multi‐species biofilms. The association between biofilm formation and antimicrobial resistance was not clearly defined. Further, viable but non‐culturable form of the foodborne pathogens is posing an unseen (by conventional cultivation techniques) but potent threat to the food safety. The present review recommends the need for carrying out systematic surveys and risk analysis of biofilms in food chain to highlight the evidence‐based public health concerns, especially in regions where microbiological food hazards are quite prevalent.
Honey has multifaceted beneficial properties, but polluted environment and unapproved apicultural practices have led to its contamination. In this study, QuEChERS method followed by chromatographic ...analysis by GC-μECD/FTD and GC-MS was validated and used for determination of 24 pesticides in 100 raw honey samples from various floral origins of Northern India. Matrix-matched calibrations showed that the method was selective and linear (r
2
> 0.99) with detection limit < 9.1 ng g
−1
for all the studied pesticides except for monocrotophos (21.3 ng g
−1
). The average recoveries at different fortification levels ranged from 86.0 to 107.7% with relative standard deviation < 20%. Pesticide residues were detected in 19.0% samples, and most prevalent compounds detected were dichlorvos in 6.0% samples followed by monocrotophos (5.0%), profenofos (5.0%), permethrin (4.0%), ethion (3.0%), and lindane (3.0%) with concentrations ranging from 58.8 to 225.5, from 96.0 to 430.1, from 14.6 to 43.2, from 27.8 to 39.6, from 25.6 to 28.0, and from 19.6 to 99.2 ng g
−1
, respectively. Honey samples originating from cotton, sunflower, and mustard crops (33.3%) that tested positive for pesticide residues were found to be significantly higher (
p
< 0.05) than the honey originating from natural and fruity vegetation (13.5%). Therefore, considering the contamination of environmental compartments due to extensive application of pesticides in the study area and their potential for subsequent transfer to honey by the expeditious bees, the results of present study proclaim that honey may be used as an indicator of environmental pollution. Further, estimated daily intakes of all contaminants were found to be at levels well below their acceptable daily intakes suggesting that consumption of honeys at current levels does not pose deleterious effects on human health. However, precautionary measures should always be taken considering the customary honey feeding in infants and cumulative effect of these chemicals in the foreseeable future.
The present study assessed the prevalence, virulence characteristics, antimicrobial resistance and biofilm-forming ability of E. coli and S. aureus recovered from egg samples in Ludhiana, Punjab. A ...total of 393 samples from hatcheries (n = 238), retail shops (n = 94), and households (n = 61) were collected. The prevalence of E. coli was observed as 11.70% and 9.16% for S. aureus. A total of 41.30% of E. coli isolates were positive for aggR gene and 52.17% were for fimA gene; while 36.11% of the S. aureus isolates were positive for coa gene. A high proportion of E. coli (76.10%) and S. aureus (69.44%) isolates were resistant toward ≥3 tested antibiotic classes. A total of 39.13% of E. coli isolates were moderate biofilm former, whereas the majority of the S. aureus (41.67%) were weak biofilm former. No significant difference regarding biofilm formation was observed between MDR and non-MDR isolates of E. coli and S. aureus. Biofilm genes viz., fimC and crl were reported in 43.47% and 80.43% of E. coli isolates, respectively; while icaA and icaD genes were reported in 58.34% and 47.22% of S. aureus isolates, respectively. A strong metabolic activity among 52.17% of E. coli and 41.66% of S. aureus isolates was observed using XTT assay. The present study highlights the need for applied food safety measures across the egg production chain of the region to prevent the development of MDR strains and biofilms.
Abstract The study investigates the efficacy of lactic acid bacteria (LAB) strains ( Lactobacillus rhamnosus and Lactobacillus casei ) in combating Escherichia coli biofilms by determining ...antibacterial, anti‐biofilm activity, auto‐aggregation, and co‐aggregation assay. The study included 115 E. coli isolates from milk ( n = 36), chicken meat ( n = 33), and chicken eggs ( n = 46). Among 115 E. coli isolates, 22.61% were strong biofilm formers. The LAB strain, L. rhamnosus exhibited a 28.47 mm mean antibacterial inhibition zone, an average reduction of 51.22% in biofilm growth, 55.46% auto‐aggregation, and 41.57% co‐aggregation with E. coli . Similarly, L. casei demonstrated a 21.55 mm mean antibacterial inhibition zone, an average reduction of 36.74% in biofilm growth, 45.23% auto‐aggregation, and 38.74% co‐aggregation with E. coli isolates. Both strains individually and in combination demonstrate substantial reductions in biofilm growth, with L. rhamnosus observed to be more effective than L. casei. Scanning electron microscopy provides valuable insights into the structural aspects of the probiotic impact on diminishing E. coli biofilm. Probiotics' ability to auto‐aggregate and co‐aggregate with pathogenic strains serves as an initial screening method for identifying suitable probiotic bacteria. In conclusion, the results underscore the efficacy of specific LAB strains in combating E. coli biofilm formation. This study provides a basis for future investigations into LAB's capacity to mitigate biofilm‐related hurdles and strengthen microbial management protocols within food processing settings or relevant food substrates.
Listeria monocytogenes is recognized as an emerging pathogen, with limited information or statistics on this pathogen. Moreover, poor hygienic practices in the unorganized meat sector favor its ...growth and survival. Therefore, the present study was carried out in Punjab, India to assess the prevalence of Listeria spp. in chevon and mutton samples, followed by its characterization. The prevalence of Listeria in chevon, mutton and swab samples collected from butchers' shops and slaughter houses was 1.82%, 3.21% and 6.66%, respectively. The 18 (2.67%) L. monocytogenes strains isolated from 786 samples carried one or more virulence-associated gene. Based on virulence genes, 6/18 isolates were potentially pathogenic. Serovar 4b (44.4%) was predominant, followed by serovars 1/2a (22.2%), 1/2b (22.2%) and 1/2c (11.1%). Detection of L. monocytogenes in meat and environment samples indicated poor hygiene, potential cross-contamination and risk of listeriosis to consumers and occupational workers. The findings of the study were also relevant to the fact that most of the slaughtering in Punjab, India is carried out in unorganized way, and this meat is not stored propery. Moreover, in the absence of a systematic foodborne disease surveillance and monitoring program, a database on foodborne diseases is absent, and needs to be established.
Brucellosis is a zoonotic disease imposing significant impacts on livestock production and public health worldwide. India is the world's leading milk producer and Punjab is the state which produces ...the most cattle and buffalo milk per capita. The aim of this study was to investigate the epidemiology of bovine brucellosis to provide evidence for control of the disease in Punjab State, India. A cross-sectional study of dairy farms was conducted in humans and livestock in rural Ludhiana district using a multi-stage sampling strategy. The study suggests that brucellosis is endemic at high levels in cattle and buffalo in the study area with 15.1% of large ruminants testing seropositive and approximately a third of dairy farms having at least one animal test seropositive. In total, 9.7% of those in direct contact with livestock tested seropositive for Brucella spp. Persons that assisted with calving and/or abortion within the last year on a farm with seronegative livestock and people which did not assist with calving/abortion had 0.35 (95% CI: 0.17 to 7.1) and 0.21 (0.09 to 0.46) times the odds of testing seropositive compared to persons assisting with calving/abortion in a seropositive farm, respectively. The study demonstrated that persons in direct contact with cattle and buffalo in the study area have high risk of exposure to Brucella spp. Control of the disease in livestock is likely to result in benefits to both animal and public health sectors.
The present study was envisaged with an aim to determine the occurrence of antibiotic residues; enrofloxacin, oxytetracycline, penicillin G, sulphamethoxazole and chloramphenicol as well as ...mycotoxins; aflatoxin M1 and ochratoxin A in raw milk samples collected from individual animals from dairy farms located in 9 districts of Punjab, India. A total of 168 raw milk samples were collected and analysed using commercially available competitive Enzyme linked immunosorbent assay kits. Out of these, 19 (11.3%) and 9 (5.4%) samples were found positive for antibiotic residues and mycotoxins, respectively. The milk samples were positive for enrofloxacin (4.8%), oxytetracycline (3.0%), penicillin G (3.0%) and sulphamethoxazole (0.6%) residues. The percentage of samples found above maximum residue limit established by Europen Union (EU)/Codex Alimentarius Commission (CAC) were 1.7%, 1.2% and 0.6% for enrofloxacin, oxytetracycline and penicillin G residues, respectively. Aflatoxin M1 was detected in 5.4% of monitored milk samples with 1.2% samples exceeded the established maximum levels of EU but were below the maximum levels established by CAC. The occurrence of antibiotic residues and mycotoxins in raw milk samples above maximum limits is a rising concern for food safety due to possibility of health risks to the consumers.
The present study was carried out with the objectives to determine the occurrence of aflatoxin M1 (AFM1) in raw milk and identification of associated risk factors from three different types of animal ...farming systems. A total of 189 pooled raw milk samples were tested for AFM1 with enzyme linked immunosorbant assay (ELISA) as screening and high performance liquid chromatography with fluorescence detection (HPLC-FLD) as confirmatory techniques. AFM1 was found positive in 58% pooled milk samples with the mean level of 0.917 µg/L, while 50.8% and 36.5% samples were found above the legal limits set by European Commission (EC) and Food safety and standard authority of India (FSSAI), respectively for AFM1 in milk. Among all investigated risk factors, feeding of readymade concentrate feed and leftover household cereals, longer feed storage duration and feed storage quality were found significantly associated with presence of AFM1 in farm milk. High prevalence as well as levels of AFM1 in farm milk poses a health risk to the consumers especially children. Therefore, efforts are urgently required to create awareness among dairy farmers about aflatoxins contamination of feed and milk, to improve farm management practices and to control AFM1 level in milk below the legal limits.
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