New strategies in the treatment of diseases caused by Acanthamoeba based on nanoparticles: a systematic review.

BACKGROUND: Acanthamoeba is one of the opportunistic parasites with a global prevalence. Currently, due to the side effects and the emergence of drug resistance to this parasite, much research has been performed on the use of nano-drugs to treat Acanthamoeba-caused diseases. Therefore, this systematic review study aims to evaluate new strategies for treating diseases caused by Acanthamoeba based on nanoparticles (NPs). METHODS: We designed a systematic review based on the articles published in English between 2000 and 2022. Our search strategy was based on syntax and specific tags for each database, including ScienceDirect, PubMed, Scopus, Ovid, and Cochrane. From the articles, those that had inclusion criteria were selected, and their data were extracted and analyzed. RESULTS: In this study, 26 studies were selected. Metallic nanoparticles were mostly used against the Acanthamoeba species (80.7%). 19.2% of the studies used polymeric nanoparticles, and 3.8% used emulsion nanoparticles. Most studies (96.1%) were performed in vitro, and only one study (3.8%) was carried out in vivo. Silver NPs were the most used metallic nanoparticles in the studies. The best effect of the anti-Acanthamoeba compound was observed for green synthesized nanoparticles based on stabilization by plant gums, loaded with citrus fruits flavonoids hesperidin (HDN) and naringin (NRG) with a 100% growth inhibition at a concentration of 50 µg/mL. CONCLUSION: This study showed that chlorhexidine and other plant metabolites loaded with silver and gold nanoparticles increase the anti-Acanthambae activity of these nanoparticles. However, green synthesized nanoparticles based on stabilization by plant gums, loaded with citrus fruits flavonoids hesperidin (HDN) and naringin (NRG), showed the best anti-Acanthambae effect. Nevertheless, further studies should be performed to determine their safety for human use.

Potential medicinal plants involved in inhibiting 3CLpro activity: A practical alternate approach to combating COVID-19.

At present, a variety of vaccines have been approved, and existing antiviral drugs are being tested to find an effective treatment for coronavirus disease 2019 (COVID-19). However, no standardized treatment has yet been approved by the World Health Organization. The virally encoded chymotrypsin-like protease (3CLpro) from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which facilitates the replication of SARS-CoV in the host cells, is one potential pharmacological target for the development of anti-SARS drugs. Online search engines, such as Web of Science, Google Scholar, Scopus and PubMed, were used to retrieve data on the traditional uses of medicinal plants and their inhibitory effects against the SARS-CoV 3CLpro. Various pure compounds, including polyphenols, terpenoids, chalcones, alkaloids, biflavonoids, flavanones, anthraquinones and glycosides, have shown potent inhibition of SARS-CoV-2 3CLpro activity with 50% inhibitory concentration (IC50) values ranging from 2-44 µg/mL. Interestingly, most of these active compounds, including xanthoangelol E (isolated from Angelica keiskei), dieckol 1 (isolated from Ecklonia cava), amentoflavone (isolated from Torreya nucifera), celastrol, pristimerin, tingenone and iguesterin (isolated from Tripterygium regelii), tannic acid (isolated from Camellia sinensis), and theaflavin-3,3'-digallate, 3-isotheaflav1in-3 gallate and dihydrotanshinone I (isolated from Salvia miltiorrhiza), had IC50 values of less than 15 µg/mL. Kinetic mechanistic studies of several active compounds revealed that their mode of inhibition was dose-dependent and competitive, with Ki values ranging from 2.4-43.8 µmol/L. Given the significance of plant-based compounds and the many promising results obtained, there is still need to explore the phytochemical and mechanistic potentials of plants and their products. These medicinal plants could serve as an effective inexpensive nutraceutical for the general public to help manage COVID-19.

Medicinal Plants as an Alternative to Control Poultry Parasitic Diseases.

Parasitic infections are a major public health concern affecting millions of people universally. This review elaborates on the potential impacts of plants and their bioactive components that have been widely used in the cure of several parasitic infections of poultry. The medicinal importance of natural herbs depends upon their bioactive ingredients, which are originated from crude plants, consequently leading to the specific action on the body. Due to the limited availability of effective drugs and high cost, the development of drug resistance in several harmful parasites and microbes leads to huge economic losses in the poultry industry. This will impose the development of innovative sources for drugs to overwhelm the therapeutic failure. Moreover, the environment-friendly feed additives which can be applied as a substitute to antibiotic growth promoters (AGP) for broilers were proven. The application of natural products with therapeutic characteristics is an ancient practice that is appropriately gaining more acceptance. Globally, it is assessed that some 20,000 species of higher plants are used medicinally, although traditional medicine has a scarcity of knowledge on its efficiency and wellbeing. This review explores the usage of medicinal herbs for parasitic infections, emphasizing the recent knowledge available while detecting the research gaps which may be explored to find the usage of herbal medicines for parasitic infections in poultry. In conclusion, herbal medicines are the effective source of prime components for drug detection and the formation of phytopharmaceuticals in the control of devastating parasitic infections. There is a prerequisite to applying the traditional medicine information in clinical applications via value addition.

Enhanced volatile fatty acids production from waste activated sludge with synchronous phosphorus fixation and pathogens inactivation by calcium hypochlorite stimulation.

An efficient approach for synchronous volatile fatty acids (VFAs) promotion, phosphorus fixation and pathogens inactivation during waste activated sludge (WAS) anaerobic fermentation was achieved with optimal calcium hypochlorite (Ca(ClO)2) stimulation. The maximal VFAs were 3.6 folds of control in reactors with 0.01 g Ca(ClO)2/g TSS addition. The low dosage of Ca(ClO)2 enhanced WAS solubilization and hydrolysis by disrupting the extracellular polymeric substance (EPS) effectively. Sufficient substrates for fermentative bacteria were thereby provided with the maintenance of acceptable microbial activity and viability. However, high dosage of Ca(ClO)2 deteriorated the performance of anaerobic fermentation due to its strong oxidative ability, resulting in cell lysis greatly. Moreover, the largely released phosphorus during WAS fermentation was effectively precipitated and removed by the combination of Ca2+ at 0.01 g Ca(ClO)2/g TSS dosage. In addition, Ca(ClO)2 had distinguished effects on pathogens inactivation. The simultaneous phosphorus fixation and pathogens reduction during VFAs production increased the utilization value of fermentation liquid and benefitted the further disposal of fermented sludge.

Phosphorus recovery as vivianite from waste activated sludge via optimizing iron source and pH value during anaerobic fermentation.

This study presented an innovative method for phosphorus (P) recovery as vivianite from waste activated sludge (WAS) via optimizing iron dosing and pH value during anaerobic fermentation (AF). The optimal conditions for vivianite formation were in the pH range of 6.0-9.0 with initial PO43- >5 mg/L and Fe/P molar ratio of 1.5. Notably, FeCl3 showed advantages over ZVI for the simultaneous release of Fe2+ and PO43- during WAS fermentation, especially in acidic conditions. The FeCl3 dosing at pH 3.0 could contribute to 78.81% Fe2+ release and 85.69% of total PO43- release from WAS. They were ultimately recovered in the form of high-purity vivianite (93.67%). Clostridiaceae (40.25%) was the predominant bacteria in FeCl3-pH3 reactors, which played key roles in inducing dissimilatory iron reduction for Fe2+ formation. Therefore, P recovery as vivianite from WAS fermentation might be a promising and highly valuable approach to relieve the P crisis.

Potentials and challenges of phosphorus recovery as vivianite from wastewater: A review.

Due to the shortage of phosphorus resources and the limitations of existing phosphorus recovery methods, phosphorus recovery in the form of vivianite has attracted considerable attention with its natural ubiquity, easy accessibility and foreseeable economic value. This review systematically summarizes the chemistry of vivianite, including the characteristics, formation process and influencing factors of the material. Additionally, the potential of phosphorus recovery as vivianite from wastewater has also been comprehensively examined from the prospects of economic value and engineering feasibility. In general, this method is theoretically and practically feasible, and brings some extra benefits in WWTPs. However, the insufficient understanding on vivianite recovery in wastewater/sludge decelerate the development and exploration of such advanced approach. Further researches and cross-field supports would facilitate the improvement of this technique in the future.