In this review, collected information related to Moringa Oleifera seeds was evaluated, such as their properties and the main active components involved in their processes, as well as their dual efficiency as both antimicrobials and natural coagulants for treating contaminated effluents. Furthermore, discussions were completed about perspectives on progress related to this field of research to understand the bioactive properties of these seed compounds, including their antibacterial, antifungal, and antiviral activity. In addition to the coagulant properties that have been quantitatively assessed, studies have examined the underlying coagulating mechanism, and seed processing techniques. In addition, the challenges associated with the use of conventional coagulants (metals or polymers) have led to numerous research efforts towards the development of natural plant-based coagulants that are eco-friendly to treat wastewater and offer a large variety of other advantages, such as their wide availability, the reduction of by-product generation, the reduction of costs, and greater biodegradability. Based on the results of different researchers, and regarding the appraisals using Moringa Oleifera seeds for wastewater treatment processes, many studies encourage their use for those operations. Due to their extensive and potent properties as an antibacterial and a coagulant, Moringa Oleifera seeds are still used today as a promising wastewater treatment method. Finally, this paper provides suggestions and comments, as well as identifies the knowledge gaps, and makes recommendations for future research development strategies, such as studying the contents of Moringa Oleifera seeds, their interactions with colloids present in wastewater, understanding their stability and behavior, assessing the performance of seed-derived flocculants according to pH values, isolating and characterizing the active compounds to determine the toxicity and optimum dose to be used as effective antimicrobials, and removing heavy metals.

Located in a semi-arid to arid region, Morocco is confronting increasing water scarcity challenges. In the circular economy paradigm, the reuse of treated wastewater in agriculture is currently considered a possible solution to mitigate water shortage and pollution problems. In recent years, Morocco has made significative progress in urban wastewater treatment under the National Wastewater Program (PNA). However, rural sanitation has undergone significant delays. Therefore, an alternative technology for wastewater treatment and reuse in rural areas is investigated in this review, considering the region’s economic, social, and regulatory characteristics. Constructed wetlands (CWs) are a simple, sustainable, and cost-effective technology that has yet to be fully explored in Morocco. CWs, indeed, appear to be suitable for the treatment and reuse of wastewater in remote rural areas if they can produce effluent that meets the standards of agricultural irrigation. In this review, 29 studies covering 16 countries and different types of wastewater were collected and studied to assess the treatment efficiency of different types of CWs under different design and operational parameters, as well as their potential application in agricultural reuse. The results demonstrated that the removal efficiency of conventional contamination such as organic matter and suspended solids is generally high. CWs also demonstrated a remarkable capacity to remove heavy metals and emerging contaminants such as pharmaceuticals, care products, etc. The removal of microbial contamination, on the other hand, is challenging, and does not satisfy the standards all the time. However, it can be improved using hybrid constructed wetlands or by adding polishing treatment. In addition, several studies reported that CWs managed to produce effluent that met the requirements of wastewater reuse in agriculture of different countries or organisations including Morocco.