A one-pot green method to synthesise Pt and Pd nanoparticles is reported. Two natural aromatic polymers, lignin and fulvic acid, were used as both reducing and stabilising agents at moderate temperature (80 °C) in water and under aerobic conditions. Full characterisation was performed using TEM, UV-vis, XRD, ¹⁹⁵Pt and ¹H NMR, FT-IR and GC-MS techniques. In the TEM images, we observed spherical nanoparticles of diameters in the range of 16 nm to 20 nm, in the case of Pd, and smaller ones of not so well defined shapes for Pt. GC-MS of the organic fractions formed during the preparation of the nanoparticles showed defined amounts of vanillin, a well known degradation product of these polymers. This finding indicates that the active participation of lignins and fulvic acids in the metal reduction step. The catalytic activity of the nanoparticles was tested for the NaBH₄ reduction of 4-nitrophenol and for the aerobic oxidation of alcohols, reactions that are always conducted under green conditions. Both Pt and Pd nanoparticles show good catalytic activity in the reduction reaction, while in the aerobic oxidation reaction only the Pt nanoparticles were effective.

Ultraviolet light can cause photodamage to the skin, such as sunburns and melanomas. TiO₂ is introduced in sunscreen formulations to reflect and scatter UV radiation. However, it can also photocatalyze the production of reactive species like O²⁻˙ and OH˙. Here, we aimed to remove the photocatalytic activity of TiO₂ (anatase and rutile), while preserving the UV filter property. Anatase and rutile were modified through two preparative protocols. The first used HCl lignin precipitation of ethylene glycol lignin solution in the presence of the cross-linker glutaraldehyde and anatase or rutile nanoparticles. The second protocol used HNO₃ lignin precipitation of lignin aqueous solution in the presence of anatase or rutile nanoparticles. Both methodologies were performed at room temperature and ambient pressure in green media, with vigorous mixing followed by 20 kHz sonication. The composite materials obtained were fully characterized by SEM, XRD analysis and FT-IR spectroscopy, and their photostability, and photo and shielding activities were evaluated through reference reactions: oxidation of 2-propanol, an ene-reaction conducted on an α,β-unsaturated carboxylic derivative and photochemical transformation of o-nitrobenzaldehyde to o-nitrosobenzoic acid. Therefore, in the near future, industrial use of these new clusters can help to minimize TiO₂ phototoxicity in sunscreen formulations, while preserving the sunscreen photoprotection activity.

A new catalytic aerobic oxidation of alcohols to aldehydes under green conditions was developed (room temperature and pressure, water solution, open vials). The water-soluble platinum(II) tetrasulfophthalocyanine (PtPcS) catalyst showed the best selectivity for carbonyl derivatives, and in particular for α,β-unsaturated alcohols; the reactions are slow.

A catalytic system consisting of metal–sulfophthalocyanines (MPcS) and monopersulfate or hydrogen peroxide as oxidants was effective in the dibenzothiophene oxidative desulfurization with various yields and selectivities. Oxidations were conducted at room temperature in acetonitrile–water mixed solvent. The dibenzothiophene oxidation involved the step by step formation of dibenzothiophene dioxide and biphenylsultone (dibenzo-1,2-oxathiine 2,2-dioxide), followed by hydrolysis to 2(2′-hydroxybiphenyl)sulfonate and finally catalytic desulfurization to 2-hydroxybiphenyl (2-phenylphenol) and sulfuric acid; all the intermediate compounds were identified. Moreover, catalytic over-oxidation of 2-hydroxybiphenyl, with ring fission and formation of various oxidation products, among them carbon dioxide, oxalic and benzoic acid, was also observed. Among the various MPcS catalysts examined (M = Fe, Co and Ru), the ruthenium derivative exhibited the best performances with persulfate and iron derivative with hydrogen peroxide; in both cases the slow step of the process consisted in the oxidation of dibenzothiophene dioxide to biphenylsultone.

Acrylamide (AA) is considered genotoxic, neurotoxic and a ‘probable human carcinogen’. It is included in group 2 A of the International Agency for Research on Cancer (IARC). The formation of AA occurs when starch-based foods are subjected to temperatures higher than 120 °C in an atmosphere with very low water content. The aim of this review is to shed light on the toxicological aspects of AA, showing its regulatory evolution, and describing the most interesting mitigation techniques for each food category involved, with a focus on compliance with EU legislation in the various classes of consumer products of industrial origin in Europe.