Controlling of Mycobacterium by Natural Degradant-Combination Models for Sequestering Mycolic Acids in Karish Cheese.

Degradation of the mycobacterial complex containing mycolic acids (MAs) by natural bioactive compounds is essential for producing safe and value-added foods with therapeutic activities. This study aimed to determine the degradation efficiency of natural organic acid extracts (i.e., citric, malic, tartaric, and lactic), quadri-mix extract from fruits and probiotics (i.e., lemon, apple, grape, and cell-free supernatant of Lactobacillus acidophilus), and synthetic pure organic acids (i.e., citric, malic, tartaric, and lactic), against MA in vitro in phosphate buffer solution (PBS) and Karish cheese models. The degradation effect was evaluated both individually and in combinations at different concentrations of degradants (1, 1.5, and 2%) and at various time intervals (0, 6, 12, 24, and 48 h). The results show that MA degradation percentage recorded its highest value at 2% of mixed fruit extract quadri-mix with L. acidophilus and reached 99.2% after 48 h both in PBS and Karish cheese, unlike other treatments (i.e., citric + malic + tartaric + lactic), individual acids, and sole extracts at all concentrations. Conversely, organic acid quadri-mix revealed the greatest MA degradation% of 95.9, 96.8, and 97.3% at 1, 1.5, and 2%, respectively, after 48 h. Citric acid was more effective in MA degradation than other acids. The fruit extract quadri-mix combined with L. acidophilus-fortified Karish cheese showed the highest sensorial characteristics; hence, it can be considered a novel food-grade degradant for MA and could be a promising biocontrol candidate against Mycobacterium tuberculosis (Mtb) in food matrices.

Binding and removal of polycyclic aromatic hydrocarbons in cold smoked sausage and beef using probiotic strains.

The aim of this study is to bio-monitor the levels of 16 polycyclic aromatic hydrocarbons (PAHs) in cold smoked beef and sausages. The ability of probiotics to remove PAHs was also investigated as function of the cell viability (viable, non-viable and acid-treated cells), bacterial counts (107, 108, and 109 CFU/mL), pH (3, 5, and 7), and incubation time (6, 12, and 24 h). The results indicated a significant difference (p < 0.05) among the analyzed sausages and beef samples for the PAHs concentration. Non-viable probiotics achieved the highest PAHs reduction rates. Limosilactobacillus fermentum EMCC 1346 presented the lowest binding activity value (i.e. 41.10-56.80 %) for all PAHs, followed by Lacticaseibacillus rhamnosus EMCC 1105 with binding percentage of 50.40-65.80 %. On the other hand, the highest removal for all PAHs was achieved by Lactobacillus bulgaricus EMCC 1102 with binding rate of 60.50-76.80 %, at 109 CFU/mL, pH 7, after incubation for 24 h. The fortified sausages results revealed that L. bulgaricus EMCC 1102 cultures exhibited the maximum and significant reduction (p < 0.05) of PAHs with values of 44.71 µg/kg for the center part, compared to control non treated sausages (82.65 µg/kg). Regarding the sensorial profile, treated samples with probiotics led to a preference from the panelists, compared to control. Consequently, the results confirm that fermented probiotic suspension is a feasible future strategy to control PAHs levels in cold smoked meat stuffs.

Evaluation of the Effectiveness of Charcoal, Lactobacillus rhamnosus, and Saccharomyces cerevisiae as Aflatoxin Adsorbents in Chocolate.

The high incidence of aflatoxins (AFs) in chocolates suggests the necessity to create a practical and cost-effective processing strategy for eliminating mycotoxins. The present study aimed to assess the adsorption abilities of activated charcoal (A. charcoal), yeast (Saccharomyces cerevisiae), and the probiotic Lactobacillus rhamnosus as AFs adsorbents in three forms-sole, di- and tri-mix-in phosphate-buffered saline (PBS) through an in vitro approach, simulated to mimic the conditions present in the gastrointestinal tract (GIT) based on pH, time and AFs concentration. In addition, the novel fortification of chocolate with A. charcoal, probiotic, and yeast (tri-mix adsorbents) was evaluated for its effects on the sensory properties. Using HPLC, 60 samples of dark, milk, bitter, couverture, powder, and wafer chocolates were examined for the presence of AFs. Results showed that all the examined samples contained AFs, with maximum concentrations of 2.32, 1.81, and 1.66 µg/kg for powder, milk, and dark chocolates, respectively. The combined treatment demonstrated the highest adsorption efficiency (96.8%) among all tested compounds. Scanning electron microscope (SEM) analysis revealed the tested adsorbents to be effective AF-binding agents. Moreover, the novel combination of tri-mix fortified chocolate had a minor cytotoxicity impact on the adsorptive abilities, with the highest binding at pH 6.8 for 4 h, in addition to inducing an insignificant effect on the sensory attributes of dark chocolate. Tri-mix is thus recommended in the manufacturing of dark chocolate in order to enhance the safety of the newly developed product.

Lead, cadmium, and aluminum in raw bovine milk: Residue level, estimated intake, and fate during artisanal dairy manufacture.

OBJECTIVE: The goal of this study was to determine the levels of lead (Pb), cadmium (Cd), and aluminum (Al) in raw bovine milk. Milk consumption was used to calculate the estimated weekly intake (EWI), provisional tolerable weekly intake (PTWI), and target hazard quotient (THQ) for individuals. Metal distribution in dairy products and byproducts was studied as a result of artisanal processing. MATERIAL AND METHODS: Seventy-five raw bovine milk samples were collected from artisanal producers in Alexandria city, West Delta, Egypt, and analyzed using the atomic absorption spectrophotometer. The effect of artisanal dairy processing on metal distribution was studied. RESULTS: The averages of Pb, Cd, and Al in milk samples were 45.06, 4.77, and 2.93 µg/l, with 13.33% and 1.33% of analyzed samples had Pb and Al levels higher than the permissible limits, respectively. The EWI values of Pb, Cd, and Al were 1.050, 0.111, and 0.068 µg/kg body weight, which contributed to about 4.20%, 1.59%, and 0.97% from the PTWI, respectively. The THQ of three metals was <1, which referred to safe consumption. Metal residues were heavily concentrated in artisanal cheese and yogurt after coagulation and fermentation compared with other dairy products. Accordingly, the maximum average and reduction values of Pb, Cd, and Al were 745.87, 51.99, and 71.58 µg/l and -72.87%, -56.5%, and -40.96% in Damietta cheese; 535.51, 40.11, and 62.43 µg/l and -24.11%, -20.74%, and -22.94%) in Kareish cheese; and 418.42, 31.26, and 50.66 µg/l and 3.02%, 5.90%, and 0.27% in yogurt, respectively. CONCLUSIONS: The results indicated that consumption of raw bovine milk did not pose a risk to Alexandria citizens. Metal concentration increased in artisanal cheese and yogurt because of metal bio-gathering after coagulation and fermentation. Fat separation, churning, and boiling milk might keep metal concentration in dairy products and byproducts at lower levels than milk. Thus, they are suggested to be applied especially in highly contaminated areas.