Human beings experience adversative effects due to the large fluoride concentrations present in potable water. Because of the low cost and simple operation, the extensively acknowledged process is adsorption. The objective of this study is to investigate the performance of some of the prepared carbons from bio-waste materials viz., Citrus limon, Citrus nobilis, Pithecellobium dulce, and Bombax malabaricum sheaths in defluoridation. Initial concentration, particle size, agitation time, adsorbent dose, and pH were the different parameters chosen to study their effect on adsorption. Studied the adsorption kinetics. Further suitability to adsorption isotherms was reviewed.

In this study, some different selected plant leaves grown in Jordan such as Citrus limon (Rutaceae), Ceratonia siliqua L., Olea europaea (Oleaceae), Washingtonia filifera, and Myoporum (Myoporaceae) were examined for removal of copper (Cu) and zinc (Zn) ions from aqueous solutions. Cu and Zn were analyzed by atomic absorption spectrometry. A pH S-2 acidometer was used for determining the acidity of leaves solution system. Our findings showed the plants leaves were relatively efficient for removal of Cu and Zn compared to activated carbon. Removal of a 5 mg/L aqueous metal solution of Cu and Zn was treated with 2.5 g oven-dried plant in a 50 mL deionized water. The removal of Cu and Zn was expressed in terms of a time function ranged between 0 and 192 hours of contact time. The uptake of Cu and Zn by plant leaves was arranged in the following order:(i)Cu: Activated carbon > Washingtonia filifera > Ceratonia siliqua L. > Olea europaea (Oleaceae) > Myoporum (Myoporaceae) > Citrus limon (Rutaceae)(ii)Zn: Activated carbon > Olea europaea (Oleaceae) > Citrus limon (Rutaceae) > Ceratonia siliqua L. > Washingtonia filifera > Myoporum (Myoporaceae)

Food contamination by aflatoxin B1 (AFB1), produced by mycotoxigenic strains of Aspergillus spp., causes severe medical and economic implications. Essential oils (EOs) are mixtures of eco-friendly natural volatile substances. Their ability to inhibit fungal growth has been investigated, while no data are available about their efficacy in inhibition of AFB1 biosynthesis. This study investigates the efficacy of five different citrus EOs to inhibit the growth and AFB1 synthesis of A. flavus through in vitro tests for a future application in food matrices. AFB1 detection was carried out by LC-ESI-TQD analytical approach. Lemon (Citrus limon (L.) Burm. f.), bergamot (Citrus bergamia Risso), and bitter orange (Citrus aurantium L.) EOs were the most effective causing a 97.88%, 97.04%, and 96.43% reduction in mycelial growth, respectively. Sweet orange and mandarin EOs showed the lowest percentage of mycelial growth reduction. Citrus EOs showed different capacity of AFB1 inhibition (lemon > bitter orange > bergamot > sweet orange > mandarin). Our results showed a dose-dependent antifungal activity of lemon, bitter orange, and bergamot EOs which at 2% (v/v) inhibited both mycelium growth and AFB1 genesis of A. flavus. Our results show that EOs’ use can be a pivotal key to recovery and reuse of citrus fruit wastes and to be used as eco-friendly fungicides for improvement of food safety. The use of EOs obtained at low cost from the residues of citric industry presents an interesting option for improving the profitability of the agriculture.