Soursop (Annona muricata) Properties and Perspectives for Integral Valorization.

The increased international interest in the properties of soursop (Annona muricata) alerts us to the sustainability of productive chain by-products, which are rich in phytochemicals and other properties justifying their industrial application in addition to reducing the environmental impact and generating income. Chemical characteristics of soursop by-products are widely known in the scientific community; this fruit has several therapeutic effects, especially its leaves, enabling it to be used by the pharmaceutical industry. Damaged and non-standard fruits (due to falling and crushing) (30-50%), seeds (3-8.5%), peels (7-20%), and leaves, although they constitute discarded waste, can be considered as by-products. There are other less cited parts of the plant that also have phytochemical components, such as the columella and the epidermis of the stem and root. Tropical countries are examples of producers where soursop is marketed as fresh fruit or frozen pulp, and the valorization of all parts of the fruit could represent important environmental and economic perspectives. Based on the chemical composition of the fruit as well as its by-products and leaves, this work discusses proposals for the valorization of these materials. Soursop powder, bioactive compounds, oil, biochar, biodiesel, bio-oil, and other products based on published studies are presented in this work, offering new ideas for opportunities for the regions and consumers that produce soursop.

Alternative sources of oils and fats from Amazonian plants: Fatty acids, methyl tocols, total carotenoids and chemical composition.

Amazonian plants possess high amounts of little-explored lipid compounds. Chemical parameters and lipophilic compounds present in twelve oils and fats from different Amazonian plants were characterized. The fatty acids identified reveal saturated fats, such as babassu oil and muru-muru fat (rich in lauric acid), ucuhuba fat (myristic acid), and bacuri fat (palmitic acid). Buriti, pracaxi, and patawa oils showed high oleic acid content. Passion fruit seed and Brazil nut oils had high levels of the polyunsaturated fatty acids rich in linoleic acid. The oleaginous plants had high unsaturation degree and high content of medium-length-chain fatty acids due to high values of iodine, saponification, and peroxide. For methyl tocols and total carotenes, a simultaneous determination method was used and revealed high levels of these vitamins in buriti oil. No previous work in the literature has described all these parameters in Amazonian oils and fats, especially regarding plant species such as bacuri, cupuassu, and ucuhuba. These results provide information on oils and fats that could be used as alternative sources of raw material for the food and pharmaceutics industries.

Inhibition of Listeria monocytogenes by Melaleuca alternifolia (tea tree) essential oil in ground beef.

The food industry has been valuing the quest for natural substances for use in food preservation aiming to meet consumer demand for safer, more natural foods with preserved nutrients. This study aimed to assess the antimicrobial potential of essential oil of Melaleuca alternifolia (EOMA) in the inhibition of Listeria monocytogenes (ATCC 7644) (L. monocytogenes) in ground beef. An in vitro screening in solid phase was performed and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined through microdilution test. The time of action of EOMA was assessed through the death-time curve at 2 × MIC and MBC. The effects of MBC on bacterial morphology were verified under scanning electron microscopy (SEM). The meat samples were inoculated with four different suspensions of L. monocytogenes (1.5 × 108 CFU/mL, 4.6 × 104 CFU/mL, 9.2 × 103 CFU/mL, and 1.2 × 102 CFU/mL) and stored at 4 ±â€¯1 °C for up to 14 days. The test samples were added with 1.5% v/w EOMA. The test of diffusion in solid medium showed L. monocytogenes ATCC 7644 was extremely sensitive to EOMA. MIC and MBC values were 0.10 µL/g and 0.15 µL/mL, respectively. The death-time curve revealed a reduction of viable cells after 1 h of contact with the oil. SEM showed that the treated cells had wrinkled surface and some cells had lower size and diameter when compared to control ones. The food matrix test indicated EOMA had antimicrobial activity in all samples except for the one inoculated with the suspension at 1.5 × 108 CFU/mL. Thus, the use of essential oil of Melaleuca alternifolia as a potential natural antimicrobial agent to preserve ground beef was promising as it was effective at low concentration. The data lay bases for new tests to be carried out in other food matrices.