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This paper aims to synthesize 6-ethyl-4-hydroxyquinolin-2(1H)-one as a new enol-type coupling component in the preparation of some 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes and evaluate the solvent effects on their absorption in ultraviolet-visible spectra.

6-Ethyl-4-hydroxyquinolin-2(1H)-one was synthesized by thermal cyclocondensation reaction of N, N′-bis(4-ethylphenyl) malonamide at 130–140°C in polyphosphoric acid. This compound was then applied in the azo-coupling reaction with some aniline-based diazonium salts, so as to prepare seven new mono-heterocyclic azo dyes. The structures of the compounds were confirmed using mass spectroscopic technique. Fourier transform infra red (FT-IR) and 1H proton nuclear magnetic resonance (1H NMR) and carbon-13 nuclear magnetic resonance (13 C NMR) studies on the structure of the azo compounds revealed that they exist as two E- and Z-isomers of hydrazone tautomer both in solid and solution state. The effects of acid and base on the visible absorption spectra of the dyes were also evaluated and discussed.

Ultra violet-visible UV-vis absorption spectra of the dyes didn’t show significant variation by changing of solvents because of intramolecular H-bonding between proposed hydrazone forms and 2- and 4-keto functions in their structures. The spectra of the dyes were not sensitive to the addition of acid but were very sensitive to base.

The synthesized 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes are new members in the 4-hydroxyquinolin-2(1H)-one azo dyes family, where very few details regarding the synthesis of such dyes are reported before in the literature. They are unique in terms of synthesis and spectral properties.

To evaluate the photochromic performance of fulgide 1‐E with ferrocene in polymer matrices.

The fulgide 1‐E with ferrocene dye 2 doped in polymethylmethacrylate was prepared and the effects of UV irradiation were studied using spectrophotometer. The reversible reaction was effected using white light. The effect of heat was also determined.

A film of the brown coloured fulgide 1‐E with ferrocene doped in PMMA polymer was irradiated with ultraviolet light (365 nm), the film turned red. The later colour was partially switched back to the original brown colour when the film was irradiated with a white light. It was found that the rate constants of photocoloration reaction at initial stages are faster than those at late stages. Similarly, the photocoloration reaction was slower than the photobleaching reaction. Photocoloration reaction decreased with the increase of the annealing temperatures, but for photobleaching reaction, the rates were almost similar (at 46 and 82°C). The fatigue resistance of the film was greatly improved when the annealing temperature increased to 82°C.

The polymethylmethacrylate polymer doped photochromic fulgide 1‐E and ferrocene 2 described in the present paper was prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds.

The photochromic materials developed can be used for different applications, such as coatings and holography.

The method developed may be used to enhance the performance of photochromic materials.

Trans fatty acids arise as a result of hydrogenation processes in margarine manufacture, and in nature in the rumen of ruminant animals. Concern that high intake of trans fatty acids may increase the risk of coronary heart disease has been strengthened by recent studies. Further, there is evidence that trans fatty acids may adversely affect foetal and neonatal growth and development. Therefore, a reduced intake of trans fatty acids seems prudent. Certain foods, particularly stick margarines, shortenings and hydrogenated frying fats, contain large amounts of trans fatty acids, and are the main reason for the rather high intake of trans fatty acids in the USA and northern European countries, including Denmark. Therefore, the National Food Agency is presently working on a legal provision to reduce the level of trans fatty acids in these products.

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

The poly(methyl methacrylate) PMMA and epoxy resin doped with photochromic spirooxazine (SO) are prepared and the effects of ultraviolet (UV) irradiation are studied using spectrophotometer. The reversible reaction is effected using white light. Photochemical fatigue resistance of these films is also studied.

Irradiation of colourless 7′,8′‐dichloro‐1,3,3‐trimethylspiro[indoline‐2,3′‐[3H]benzo[b][1,4]oxazine] (SO) doped in PMMA and epoxy resin with UV light (366 nm) results in the formation of an intense purple‐red coloured zwitterionic photomerocyanine (PMC). The reverse reaction is photochemically induced by irradiation with white light. Photocolouration and photobleaching reactions follow a first‐order rate equation. It is found that photocoloration rate constant of (SO) in both matrices is almost the same, which is unexpected. On the other hand, the rate of photobleaching reaction of (PMC) in PMMA is twice slower than that in the epoxy resin. It seems that the presence of the two chlorine atoms at positions 7′ and 8′ of the benzooxazine moiety destabilise the PMC in epoxy resin film and results in speeding up the fading process compared to that in PMMA. SO doped in epoxy resin shows much better fatigue resistance than that doped in PMMA.

The PMMA and epoxy resin polymers doped photochromic spirobenzooxazine described in this paper were prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds.

The photochromic materials developed can be used for different applications, such as coatings and holography.

The method developed may be used to enhance the performance of photochromic materials.

Purpose: Evidence of adverse health effects of artificial trans fatty acids (TFAs) have accumulated since 1990s, yet TFAs are widely used by several food manufacturers around the world. This review aimed to: ascertain the available evidence of the known unfavourable biochemical properties of artificial TFAs, their metabolic functions and health consequences; estimate their average intake levels and trends in different countries in order to critically evaluate whether more action is required to eliminate them from the diet. Methodology: The published evidence was searched by employing: Medline, Pubmed, InterScience, BioMed Central and Annual Reviews. Findings: With reference to human health, evidences from epidemiological, retrospective and observational studies revealed that the consumption of TFAs could outweigh the health risks posed by saturated fat consumption. The main health concerns included unfavourably altered blood cholesterol concentrations, insulin resistance, foetal brain and neural disturbances, proinflammatory and carcinogenic responses. Great variation exists in the global trends of industrial TFAs intake, being low in Mediterranean region, Japan and Scandinavia and high in parts of United States of America and Iceland. Besides the intense use of TFAs by food manufacturers and in eateries, the use of TFAs in food products is often poorly regulated and ill‐informed to consumers. Value: Since competitive alternatives to TFAs have made them non‐mandatory a broad public health intervention at government level to regulate or completely eliminate them from the national diet is warranted.

Fish is subjected to different methods of preparation and a major challenge facing consumers is maintaining and preserving the nutritional quality of cooked fish. This paper aims to examine the effects of different cooking methods (baking, boiling, deep‐frying, pan‐frying, microwaving and grilling) on total carotenoids and lycopene content in muscle and skin fractions of Omani kingfish.

Fresh, commercially harvested kingfish samples were purchased from a supermarket and prepared using six commonly used cooking methods. Raw fish samples were used as control. Muscle and skin fish portions for each cooking method and raw samples were analyzed for total carotenoids and lycopene contents.

The paper finds that cooking methods affected kingfish skin and muscle differently. The positive effects of cooking methods on kingfish muscle scored from high to low are as follows for total carotenoids content: grilling, microwaving, pan‐frying, boiling, deep‐frying and baking; and grilling, microwaving, boiling, deep‐frying, baking and pan‐frying for lycopene content. Baking resulted in the highest increase in both total carotenoids and lycopene contents in the skin, followed by grilling and pan‐frying for total carotenoids. In conclusion, grilling, followed by microwaving, is finds to be the best cooking method for high‐carotenoids content and healthy eating of kingfish.

This is the first paper to be reported on the effects of different cooking methods on total carotenoids content (including lycopene) in skin and muscle of kingfish caught in the warm waters of the Gulf of Oman.

This study aims to focus on the possibility of developing new thiazole azo dyes with good colouristic application properties, biological and pharmacological activities.

Coupling of curcumin with different aromatic diazonium salts of 2-amino thiazole derivatives, such as 2-aminobenzothiazole, 2-amino-5-phenylthiazole, 2-amino-5-methylthiazole and 2-amino-5-nitrothiazole-produced novel azo dyes. Structures of all synthesised dyes were fully confirmed via spectroscopic and analytical methods. Those compounds were examined for their antimicrobial, anticancer and antioxidant activities. They were applied on polyester fabrics and, subsequently, their dyeing properties, light, washing, perspiration, rubbing and sublimation fastness were determined.

Prepared dyestuffs were suitable for dyeing polyester fabrics. It was found that all prepared dyes possess high colour strength, as well as good overall fastness properties. Meanwhile, the synthesised compounds exhibited good biological and pharmacology activity.

Synthesis of these four azo dyes for textile dyeing was not conveyed earlier.

Thaizolyl disperse dyes were responsible for giving better colour assessment and fastness properties on polyester fabrics.

Although, most of synthesis eco-friendly dyes are expensive, they are showing a good antimicrobial and anticancer activity.

It gave straightforward approach to synthesise novel thiazolyl azo dyes with good biological, pharmacology activities, good colour assessment, and fastness properties.

This study aims to investigate the effects of nano or inorganic fillers on unsaturated polyester’s (UPE) thermal, mechanical, and physical properties. UPE reinforced with nanoparticles shows better properties than the pure polymer itself. Nano or inorganic fillers are used in the polymeric matrix to improve thermal, mechanical and physical properties.

To improve thermal, mechanical and physical properties, UPE resin was modified with silica (S), boron nitride (BN) and S/BN hybrid nanoparticles at different ratios. Viscosity and solids content measurement, Fourier transform infrared spectroscopy, contact angle measurement, scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and thermal conductivity coefficient tests were performed on the samples.

In the SEM analysis, the UPE sample showed a smooth appearance, while all samples containing additives showed phase separation and overall heterogeneous distribution. TGA results demonstrated that the thermal stability of the resin increased in the presence of S and BN additives. According to the results, it was observed that the presence of S and BN additives in the UPE resin and the use of certain ratios improved the resin properties.

As a result of the literature search, to the best of the authors’ knowledge, no study was found in which BN nanoparticles were included in the UPE resin together with S.

This study aims to synthesize some new curcumin containing Aroyl derivatives dyestuffs and study their application in dyeing polyester fabrics, rendering to their antibacterial evaluation.

Modification of curcumin dye was carried out by introducing benzoyl rings through coupling with curcumin. All newly synthesized dyes were characterized by elemental analyses and spectral data (IR, 1 H-NMR and MS). Moreover, the optimal dyeing condition was assigned. Antibacterial activities of the dyed samples at different concentrations of both dyes were studied against gram positive (Staph aureus) and gram-negative (Salmonellatyphimurium) bacteria.

Synthesized curcumin containing benzoyl dyes were applied on polyester fabrics. Meanwhile, these synthesized dyes showed reasonable results towards fastness properties at optimal conditions matching the curcumin dye. In addition to their good fastness assets, synthesized dyes displayed antibacterial efficacy towards both gram positive and gram-negative bacteria. The dyed polyester fabrics showed higher antibacterial efficacy after multiple events of washing.

The synthesized benzoyl containing curcumin moiety was not described before.

Disperse dyes derived from curcumin were prepared via coupling of various diazonium salts of p-aminobenzaldhyde, p-aminoacetopheneone, p-aminobenzoic acid and p-aminobenzoyl chloride with curcumin. The resulting disperse dyes were applied on polyester fabrics at optimal conditions, and antibacterial efficacy of dyed fabrics were evaluated.

Curcumin being was used in food colouration and was effective for dyeing and antimicrobial finishing on textile fabrics. Novel antibacterial dyestuff containing curcumin moieties with benzoyl amine coupling components showed interesting colourant for polyester fabrics. This work introduced innovative disperse dyes for medical textile applications.

Wine, fruits, vegetables and whole grains are the main products of a healthy diet. The purpose of this paper is to scrutinize the existence of an interesting and evocative bond among moderate intake of wine, health and well-being.

By means of a fuzzy cluster analysis, the authors try to investigate the existence of groups of regions similar in wine consumption, subjective well-being, health and social relations. The latter are expressed through composite indicators, built and developed by Istat within the Italy ESW project’s activities (equitable and sustainable well-being). The analysis also investigates how this link has evolved over time. Data are related to refer to the situations in 2010 and 2017 in 21 regions of Italy.

Results obtained in 2010 seem to confirm the hypothesis of the existence of a link among moderate wine consumption, hedonism well-being and health, and in addition, findings highlight the so-called North‒South gap, that is the strong differences and economic issues among the different areas of the country. Then, outcomes obtained for 2017 appear in line with 2010 results.

Several authors from medicine, economics and chemistry domain strongly suggest and demonstrate that regular and moderate intake of wine reduces the incidence of heart disease, diabetes mellitus and hormonal problems, and correlatively increases longevity. In this work, the authors develop further research step including the aspects related to personal well-being and social relations under the umbrella of a hedonism approach. Finally, results highlight the existence of an amazing tie among moderate intake of wine consumption, well-being and health.