Vegetable farming is an activity sensitive to the dynamism of the population and to the level of intensification in the use of soil resources. A study was conducted in the peri-urban zones of Yaoundé to present the socioeconomic characteristics of vegetable farming and the farmers' perception of soil and water degradation as a result of this activity. A semi-structured questionnaire was administered to this purpose in 2016 in two vegetable farming sites in Yaoundé, namely Nkolbisson and Nkolondom III. Results showed that most vegetable farmers from both sites (around 75%) lack training in agriculture while 74 and 90 didn't benefit from training on management of pesticides. Spreading and landfilling of amendments are the two most popular ways of applying fertilizers. In fact, while the majority (35.4%) of these fertilizers is applied at planting time, the minority (4.9%) is applied several months before planting. Besides young plots are more exploited (52.4% and 30%) compared to older ones (2.4% and 5%) in Nkolondom III and Nkolbisson respectively, as they are more responsive to fertilizer application. As consequence, high rates of fertilizers are applied to the oldest farms. As for irrigation water, it is altogether polluted. Base on the above, the farmers' perception of degradation is seen through the degradation of soils properties with time in the order of 14.3% to 60% and 15% to 44% at Nkolbisson and Nkolondom III respectively resulting in a gradual decrease of crop production (up to 50%). It is also seen through the polluted produce obtained from irrigation and cleaning water.

8106positive for aminoglycosides and/or quinolones and/or macrolides (17.24%) and beta-lactam and/or sulfonamides and/or tetracyclines (51.72%). Residues of aminoglycosides and/or quinolones and/or macrolides were detected in 25% of curds, 2.38% of pasteurized milk and 16.66% of yoghurt while, the residues of beta-lactam and/or sulfonamides and/or tetracyclines were detected in 70% of curds, 66.66% of pasteurized milk and 38.88% of yoghurt. Conclusion and Application: Milk and dairy products are contaminated by antibiotics residues of different families exceeding the authorized maximum limits. Therefore, measures to raise awareness of farmers and quality control of dairy products must be made to preserve the health of consumers.

Ultrasound (US) and ozone processing allow achieving food technological aims such as the improvement of food safety and preservation. The combination of these technologies has been reported to be beneficial in inactivating microorganisms from fruits and vegetables. However, treatment conditions and mechanisms of action of these technologies can affect vegetables or fruits structure as well as their phytochemical components. This study therefore, aimed to evaluate the antimicrobial capacity of ultrasound and ozone alone or combined on artificially inoculated cabbage with E. coli and Salmonella. The impact of these decontamination processes on cabbage intercellular structure, pH, total phenol, total flavonoid and antioxidant activities were also determined. Results showed that the combination treatment significantly inactivated populations of artificially inoculated E. coli and Salmonella compared to individual processing. The inactivation effectiveness was greatly enhanced with increased ozone concentration (1.5 mg/L) and processing time, with no detectable bacteria in the washing water after only 8 min of treatment. Furthermore, ultrasound treatment alone for 8 min led to improved cabbage content of phenol, flavonoid and antioxidant activity without affecting its intercellular structure. However, the combination treatment exerted a slight decrease of these components though not statistically significant compared to untreated samples. A significant decrease was observed with the longest exposure time (20 min). We conclude that ultrasound individual treatment or its combination with ozone can be used as sanitizer to not only reduce microorganisms from fresh cabbage but also maintain its appearance quality and improve its bioactive properties and antioxidant activity. Practical applications This study was conducted to evaluate the inactivation effectiveness of ultrasound and ozone on inoculated cabbage leaves. To make an effective disinfection on the leaves, US and ozone have been combined, which resulted in a reduction of treatment time and maintenance of the bioactive compounds, the antioxidant activity and How to cite this article: Traore MB, Sun A, Gan Z, et al. Assessing the impact of the combined application of ultrasound and ozone on microbial quality and bioactive compounds with antioxidant attributes of cabbage (Brassica

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The high frequency and incidence of foodborne outbreaks related to fresh vegetables consumption is a major public health concern and an economic burden worldwide. This study evaluated the effect of individual and combined application of ultrasound (40 kHz, 100 W) and ozone on the inactivation of foodborne Escherichia coli and Salmonella, as well as their impact on cabbage color and vitamin C content. Plate count, scanning electron microscopy (SEM), and flow cytometry (FCM) following single or double staining with carboxyfluorescein diacetate and (or) propidium iodide were used to determine bacterial inactivation parameters, such as cell culturability, membrane integrity, intracellular enzyme activity, and injured and dead cells. The results of FCM and SEM showed that ultrasound treatment affected bacteria mainly by acting on the cell membrane and inactivating intracellular esterase, which resulted in bacterial death. Furthermore, when combined with ozone at 1.5 mg/L, the maximum reduction of bacterial populations was observed at 8 min with no damage on the surface of treated leaves. Therefore, fresh products sanitization using a combination of ultrasound and ozone has the potential to be an alternative for maintaining the color and vitamin C content of green cabbage.