Diego Lomonaco

Study of technical CNSL and its main components as new green larvicides

Larvicidal activities against Aedes aegypti of technical cashew (Anarcadium Occidentale L.) nut shell liquid (CNSL) and its main constituents, cardanol, cardol and their products of hydrogenation were evaluated. In addition, the structure-activity relationship is also discussed.

Cashew nut oil: opportunities and challenges in the context of sustainable industrial development

The new millennium is marked by a growing search for renewable fuels and alternative raw materials from biomass in the petrochemicals industry. However, there are many challenges to overcome regarding technological and human resources aspects. In this scenario, cashew nut oil, which is rich in natural phenols, is considered to be very promising for the development of synthetic and functional products and as a feedstock for production of fine chemicals and a wide variety of new materials.

Thermo-oxidative evaluation of new cardol derivatives as antioxidants for mineral oils

In this study, the thermo-oxidative stability of two new phosphorylated derivatives of cardol, a compound from the cashew (Anacardium occidentale L.) industry waste CNSL (cashew nutshell liquid), were evaluated. The antioxidant capacity of these new molecules upon two mineral oils, NH10 and NH20 were also studied by thermogravimetric analysis (TG/DTG), observing the onset and offset temperatures variation. The results showed that both MP and DP Cardol increased considerably the onset and offset temperatures of NH10 and NH20 oils.

Cashew Nutshell Liquid (CNSL): From an Agro-industrial Waste to a Sustainable Alternative to Petrochemical Resources

The global concern about the problems caused by the growing consumption of petrochemical compounds, such as global warming and the diminishing of fossil fuels reserves, has given rise to the green chemistry field—based on the design of products and processes that minimize the use and generation of hazardous substances—in both academy and industry. In face of the increasing demand for chemicals, sustainable and innovative technologies are necessary in order to overcome current difficulties and also avoid the evolution of new ones. The advent of agro-industry waste as a resource of raw materials has attracted the attention of researchers and opened a window of opportunity for the breakthrough of alternative products to the oil industry. In this sense, cashew nutshell liquid (CNSL), a by-product from cashew industrial processing and one of the richest natural sources of phenolic compounds, emerges as a promising and renewable feedstock for the development of a wide range of functional products. This chapter is focused on the discussion of the origin and chemical composition of the different types of CNSL, and also on the challenges involved in the methods of isolation and main applications of its major component, cardanol, in the context of a sustainable development.

Thermal and mechanical properties of biocomposites based on a cashew nut shell liquid matrix reinforced with bamboo fibers

Cardanol–formaldehyde thermoset resin was reinforced with raw and chemically modified fibers of bamboo (Bambusoideae). Modified fibers were treated with alkali solutions of NaOH (5% and 10%) and bleached with sodium hypochlorite NaClO/H2O (1:1) at 60℃–75℃. The biocomposites were fabricated with a hand lay-up technique. This study investigated the fibers microstructure before and after alkali treatment, as the interaction between matrix and reinforce by scanning electron microscopy. The Fourier transform infrared spectra allowed the identification of characteristic stretching frequencies attributed to the methyl groups of lignin. A considerable increase in thermal stability was observed in the materials studied, which was verified by thermogravimetric analysis and confirmed by X-ray diffraction. The tensile tests showed that the mechanical properties (tensile modulus, tensile strength, and elongation at break) of bamboo fibers improved after alkali treatment, as well as the increase in the biodegradation in simulated soil, showing that the alkaline treatment acted removing the macro components of the fibers (lignin and hemicellose), making them more susceptible to the action of microorganisms.

Cardanol-Based Heterocycles: Synthesis and Applications

This chapter provides an overview of the progresses of research activities related with the synthesis of functional heterocyclic systems utilizing mainly cardanol—or structural analogous (i.e., anacardic acid, cardol, methylcardol) deriving from the cashew nut shell liquid—as starting material, a renewable feedstock having significant perspectives in the field of the green chemistry and design of innovative environmentally friendly chemical processes.

Efficacy of new natural biomodification agents from Anacardiaceae extracts on dentin collagen cross-linking

OBJECTIVES Several polyphenols from renewable sources were surveyed for dentin biomodification. However, phenols from cashew nut shell liquid (CNSL, Anacardium occidentale) and from Aroeira (Myracrodruon urundeuva) extract have never been evaluated. The present investigation aimed to compare the dentin collagen crosslinking (biomodification) effectiveness of polyphenols from Aroeira stem bark extract, proanthocyanidins (PACs) from grape-seed extract (Vitis vinifera), cardol and cardanol from CNSL after clinically relevant treatment for one minute. METHODS Three-point bending test was used to obtain the elastic modulus of fully demineralized dentin beams before and after biomodification, whilst color change and mass variation were evaluated after four weeks water biodegradation. Color aspect was assessed by optical images after biodegradation whereas collagen cross-linking was investigated by micro-Raman spectroscopy. Statistical analysis was performed with repeated-measures two way ANOVA and Tukeys test (p<0.05). RESULTS The increase in elastic modulus after biomodification was in the order cardol>cardanol>aroeira=PACs with cardol solution achieving mean 338.2% increase. The mass increase after biomodification followed the same order aforementioned. Nevertheless, after four weeks aging, more hydrophobic agent (cardanol) induced the highest resistance against water biodegradation. Aroeira and cardol attained intermediate outcomes whereas PACs provided the lower resistance. Tannin-based agents (Aroeira and PACs) stained the specimens in dark brown color. No color alteration was observed with cardol and cardanol treatments. All four agents achieved crosslinking in micro-Raman after one minute application. SIGNIFICANCE In conclusion, major components of CNSL yield overall best dentin biomodification outcomes when applied for one minute without staining the dentin collagen.

Cashew tree wood flour activated with cashew nut shell liquid for the production of functionalized composites

Abstract This work is aimed at the one-step chemical modification of the surface of cashew wood flour particles using the technical grade cashew nut shell liquid (CNSL). The goal is to develop an alternative way to introduce chemically active sites on the surface of the particles, which allows the addition of new functionalities to such particles. The influence of time and temperature and catalyst on the substitution of lignocellulosic hydroxyls with cardanol/cardol urethane derivatives was evaluated by thermogravimetric analysis, scanning electron microscopy, Fourier-transform infrared spectroscopy (FTIR), and contact angle measurements. The mechanical behavior of the modified particles in polypropylene composites was also evaluated by mechanical testing and dynamic mechanical thermal analysis. The FTIR, thermogravimetry, and contact angle results indicated changes on the particle surface, and the mechanical and thermomechanical behavior of the mercerized and modified particles in the composites was found to be similar. These results point that the CNSL approach is a viable way to chemically modify cashew wood flour particle surfaces, while maintaining their properties.

Developing eco-friendly methods for purification of compounds derived from hydrogenated cardanol

ABSTRACT The present work made a comparative study between two purification methods, column chromatography and recrystallization, for compounds derived from cardanol, a by-product of the cashew industry (Anacardium occidentale L.). The compounds were successfully synthesized and characterized, focusing our attention to results obtained in terms of yield, purity, generation of solid waste and amount of solvent used in each purification process. For all the synthesized compounds, the amount of solvent used was greatly reduced in the recrystallization process, with purities above 80%, when compared to chromatographic column, which still demands high amounts of eluent.

Cardanol-based green nanovesicles with antioxidant and cytotoxic activities

ABSTRACT This manuscript describes the preparation of green nanovesicles by using cardanol as renewable starting material with embedded minor amounts of phthalazines, a class of heterocyclic bioactive compounds. The nanovesicles were prepared by stirring induced self-assembly in aqueous medium without involvement of any organic solvent. Dynamic light scattering studies and transmission electron microscopy revealed the formation of nanostructure with an average diameter in the range of 227–375 nm and a well defined spherical morphology. Potential antioxidant activity of nanovesicles were evaluated for the first time by 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging assay and bleomycin-dependent DNA damage. Moreover, their cytotoxic effects were also investigated by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay on different tumour cell lines. Unloaded nanovesicles showed moderate antioxidant and antitumoural activity that was further enhanced particularly by embedding the 2-[4-(4-Hydrazinophthalazin-1-yl)-phenyl]-isoindole-1,3-dione compound.