Annona muricata L. is a tropical tree that is used in traditional medicine around the world. The high content of flavonoid, alkaloid, acetogenin, phenolic and lipophilic compounds of this tropical tree forms the basis of its traditional medical uses. Our objective was to study soursop leaf extracts to support their use as antiviral therapies and investigate their protective effects against oxidative damage. The aqueous extract (AE) and acidified ethanolic extract (AEE) of soursop leaves were characterized by ultra performance liquid chromatography (UPLC), and their effects on human erythrocytes and in vitro antioxidant capacity, as evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays, were investigated. The antiviral effects were evaluated using a bacteriophage surrogate. AEE showed the highest phenolic content, with rutin as the predominant compound. This extract showed higher values in the DPPH and ABTS assays, with 23.61 ± 0.42 and 24.91 ± 0.16 mmol of Trolox equivalent per gram, respectively. Inhibition of hemolysis was 34% and 51% for AE and AEE, respectively. AEE was selected for the antiviral study because of its higher antioxidant activity. The viral reduction ranged from 5–6 log10 plaque-forming units/volume (PFU) at contact times of 15–360 min. Soursop leaves have a positive effect on reducing oxidative stress in human erythrocytes and viral infections.

In this study, chitosan was chemically modified with 2-methylpyridine. Subsequently, the modified chitosan was cross-linked to cellulose using succinic anhydride. Additionally, the capacity of cellulose derivatives to adsorb Pb(II) ions in an aqueous solution was studied through the determination of Pb(II) ions concentration in water, using microwave plasma atomic emission spectroscopy (MP-AES). A maximum adsorption capacity of 6.62, 43.14, 60.6, and 80.26 mg/g was found for cellulose, cellulose-succinic acid, cellulose-chitosan, and cellulose-chitosan-pyridine, respectively. The kinetic data analysis of the adsorption process showed a pseudo-second-order behavior. The increase in metal removal from water is possibly due to metal chelation with the carbonyl group of succinic acid, and the pyridine groups incorporated into chitosan.

The herbicides are used frequently to fight the proliferation of weeds. The use of herbicides correlates with an improvement in agricultural yield, but the harm to the health of human populations is well established and has been demonstrated in numerous scientific studies. In many developing countries, farmers build their own homes, and this, along with the application of herbicides in their fields, increases their exposure, through both contact with skin and respiration. It is scientifically proven that herbicides cause infertility, kidney problems, endocrine disruption, apoptosis, cytotoxicity, and neurotoxic effects. Such diseases impact the quality of those affected, and naturally the contaminated environment negatively affects human health. This chapter focuses on revising the most relevant studies regarding the health effects on agricultural workers living in rural environments due to herbicide contamination and how to sustain the herbicide use.

The versatile combination of metal nanoparticles with chemotherapy agents makes designing multifunctional drug delivery systems attractive. In this work, we reported cisplatin’s encapsulation and release profile using a mesoporous silica-coated gold nanorods system. Gold nanorods were synthesized by an acidic seed-mediated method in the presence of cetyltrimethylammonium bromide surfactant, and the silica-coated state was obtained by modified Stöber method. The silica shell was modified first with 3-aminopropyltriethoxysilane and then with succinic anhydride to obtain carboxylates groups to improve cisplatin encapsulation. Gold nanorods with an aspect ratio of 3.2 and silica shell thickness of 14.74 nm were obtained, and infrared spectroscopy and ζ potential studies corroborated surface modification with carboxylates groups. On the other hand, cisplatin was encapsulated under optimal conditions with an efficiency of ~58%, and it was released in a controlled manner over 96 h. Furthermore, acidic pH promoted a faster release of 72% cisplatin encapsulated compared to 51% in neutral pH.

In the present study, arsenic, cadmium, lead, and manganese contamination in propolis was assessed. A total of 12 raw propolis samples were analysed using atomic emission spectrometry with inductively coupled plasma (ICP-OES) for each of the metals. The analyses revealed that the samples were contaminated with each of the following metals: arsenic (ranging from <0.21 to 0.4 ppm), cadmium (<0.008 to 0.123 ppm), lead (0.580 to 117.01 ppm), and manganese (4.22 to 47.57 ppm). Lead levels exceeded the acceptable limits for consumption. A chemometric characterization was performed, looking at the correlation between elemental contamination, showing high correlation between cadmium and manganese levels (r = 0.80). Furthermore, the samples with the highest contamination levels were in areas with high industrial and agricultural activity. A risk assessment for toxic metals indicated a risk associated with lead. While the amount of lead present in the propolis samples was deemed to pose a low carcinogenic risk, it is noteworthy that the levels of the other metals detected do not pose any discernible health risk associated with the consumption of propolis. This conclusion is crucial for understanding the safety profile of propolis as a dietary supplement or natural product.