Recovery of l-tryptophan from dilute aqueous feed by extractive solvent sublation and solvent extraction methods and optimization

Preparation of Microsponge Drug Delivery System (MSDDS) Followed by a Scale-Up Approach

In 1987, Won invented the solid-phase porous microsphere (MS), which stores bioactive compounds in many interconnected voids. Spherical particles (5-300 μm), MS, may form clusters of smaller spheres, resulting in many benefits. The current investigation focussed on gel-encased formulation, which can be suitable for dermal usage. First, quasi-emulsion (w/o/w) solvent evaporation was used to prepare 5-fluorouracil (5 FU) MS particles. The final product was characterized (SEM shows porous structure, FTIR and DSC showed drug compatibility with excipients, and gel formulation is shear-thinning) and further scaled up using the 8-fold method. Furthermore, CCD (Central Composite Design) was implemented to obtain the optimized results. After optimizing the conditions, including the polymer (600 mg, ethyl cellulose (EC), eudragit RS 100 (ERS)), stirring speed (1197 rpm), and surfactant concentration (2% w/v), we achieved the following results: optimal yield (63%), mean particle size (152 µm), drug entrapment efficiency (76%), and cumulative drug release (74.24% within 8 h). These findings are promising for industrial applications and align with the objectives outlined in UN Sustainable Development Goals 3, 9, and 17, as well as the goals of the G20 initiative.

Influence of suspended particles and dissolved organic matters on virus enrichment in reclaimed water by two-step tangential flow ultrafiltration: Phenomena and mechanisms

Enteric virus concentration in large-volume water samples is crucial for detection and essential for assessing water safety. Certain dissolution and suspension components can affect the enrichment process. In this study, tangential flow ultrafiltration (TFUF) was used as an enrichment method for recovering enteric virus in water samples. Interestingly, the bacteriophage MS2 recovery in reclaimed water and the reclaimed water without particles were higher than that in ultrapure water. The simulated reclaimed water experiments showed that humic acid (HA) (92.16% ± 4.32%) and tryptophan (Try) (81.50 ± 7.71%) enhanced MS2 recovery, while the presence of kaolin (Kaolin) inhibited MS2 recovery with an efficiency of 63.13% ± 11.17%. Furthermore, Atomic force microscopy (AFM) revealed that the MS2-HA cluster and the MS2-Try cluster had larger roughness values on the membrane surface, making it difficult to be eluted, whereas MS2-Kaolin cluster had compact surfaces making it difficult to be eluted. Additionally, the MS2-HA cluster is bound to the membrane by single hydrogen bond with SO, whereas both the MS2-Try cluster and the MS2-Kaolin cluster are bound to the membrane by two hydrogen bonds, making eluting MS2 challenging. These findings have potential implications for validating standardized methods for virus enrichment in water samples.

Valorization of wastewater to recover value-added products: A comprehensive insight and perspective on different technologies

In recent years, due to rapid globalization and urbanization, the demand for fuels, energy, water and nutrients has been continuously increasing. To meet the future need of the society, wastewater is a prominent and emerging source for resource recovery. It provides an opportunity to recover valuable resources in the form of energy, fertilizers, electricity, nutrients and other products. The aim of this review is to elaborate the scientific literature on the valorization of wastewater using wide range of treatment technologies and reduce the existing knowledge gap in the field of resource recovery and water reuse. Several versatile, resilient environmental techniques/technologies such as ion exchange, bioelectrochemical, adsorption, electrodialysis, solvent extraction, etc. are employed for the extraction of value-added products from waste matrices. Since the last two decades, valuable resources such as polyhydroxyalkanoate (PHA), matrix or polymers, cellulosic fibers, syngas, biodiesel, electricity, nitrogen, phosphorus, sulfur, enzymes and a wide range of platform chemicals have been recovered from wastewater. In this review, the aspects related to the persisting global water issues, the technologies used for the recovery of different products and/or by-products, economic sustainability of the technologies and the challenges encountered during the valorization of wastewater are discussed comprehensively.