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Article

R. Usop, Z.H.Z Abidin, N.A. Mazni, A.N. Hadi, N.A. Halim, R.M. Taha, M.A. Careem, S.R. Majid and A.K. Arof

This paper aims to study the colour stability of chlorophyll and the effect of copper (II) nitrate – Cu(NO3)2 – as an additive in natural dye coating films after being…

Abstract

Purpose

This paper aims to study the colour stability of chlorophyll and the effect of copper (II) nitrate – Cu(NO3)2 – as an additive in natural dye coating films after being exposed to ultraviolet-A (UV-A).

Design/methodology/approach

The natural dye was extracted from the leaves of Cassia alata L. using absolute ethanol as the solvent. The extract was divided into two parts and, one of it was added with 3 wt.% Cu(NO3)2 as an additive. The polymer blend of poly(methyl methacrylate) (PMMA) and acrylic polyol was used as the coating binder. Both parts of the dye with and without additive were mixed with the blended polymer in a specific ratio. The resulted mixtures were applied as coating films on glass substrates. The colour stability of the coating films on exposure to UV-A with the time of exposure was observed with Commission internationale de l’éclairage (CIE) L*a*b* colour coordinates. The hidden power by the means of reflectivity and glossiness of the coatings was also studied. Statistical standard deviation (STD) was used to analyse the data.

Findings

The test showed that the coating films containing Cu(NO3)2 had smaller colour differences, (ΔE*) indicating higher colour stability. The analysis on hidden power also showed that the coating film with Cu(NO3)2 was 1.6 times more stable than the film without additive. All the measurements in this study were observed within 35 days of duration.

Research limitations/implications

This paper implies the potential of using natural dye extracted from Cassia alata L. leaves as a stable dye colourant for coating applications.

Practical implications

The coating film developed in this study is suitable for glass substrate applications.

Originality/value

A new method of preparing solvent-based coating film from PMMA–acrylic polyol with chlorophyll colourant is introduced in this study.

Details

Pigment & Resin Technology, vol. 45 no. 3
Type: Research Article
ISSN: 0369-9420

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Article

Nordiyanah Anuar, R.M. Taha, Noraini Mahmad, Sadegh Mohajer, Siti Aisha Na’illa Che Musa and Zul Hazrin Zainal Abidin

The aim of the present study is to gain correlation between saffron colours, their antioxidant capacity and the constituents of the secondary metabolites of three…

Abstract

Purpose

The aim of the present study is to gain correlation between saffron colours, their antioxidant capacity and the constituents of the secondary metabolites of three different saffron samples commonly available in the Malaysian market.

Design/methodology/approach

In this study, saffron samples imported from Iran, Spain and Kashmir were extracted using methanol and the total antioxidant capacity were analysed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging assay. Ultra-high performance liquid chromatography (UHPLC) and electrospray ionization coupled with mass spectrometry (ESI-MS/MS) were then used to identify secondary metabolites present in the saffron crude extracts. The colour variation of the saffron extract was expressed by the CIELAB colorimeter in terms of lightness (L*), greenness (a*), yellowness (b*), chroma (C) and hue angle (H°). Principle component analysis (PCA) was carried out to analyse the similarities and correlation between variables.

Findings

This study reveals that antioxidant has a positive correlation with flavanols, especially quercetin and kaempferol. In addition, colour appearance is not necessarily an indicator for the antioxidant level.

Research limitations/implications

The major classes of polyphenolics identified in saffron methanolic crude extract are flavonoids and phenolic acids. Further improvements in the extraction and identification methods may find other compounds that could attribute to the visual factors and antioxidant capacity as a complement for this preliminary study.

Practical implications

This analysis provides comparison basis and valuable information for saffron consumers in Malaysia depending on the consumers’ purpose of whether to have a certain desired colour or health benefits.

Originality/value

A comparative study about saffron product available in Malaysian market is original. To the best of the authors’ knowledge, this is the first attempt of evaluation on a saffron product that has been carried out in Malaysia.

Details

Pigment & Resin Technology, vol. 46 no. 2
Type: Research Article
ISSN: 0369-9420

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Article

A.K. Arof, N.A. Mat Nor, N.R. Ramli, I.M. Noor, N. Aziz and R.M. Taha

The purpose of the paper is to study the effect of color stability on introducing chenodeoxycholic acid (CDCA) into a colored liquid extract from saffron and determine the…

Abstract

Purpose

The purpose of the paper is to study the effect of color stability on introducing chenodeoxycholic acid (CDCA) into a colored liquid extract from saffron and determine the color quality of the extract over a nine-month period.

Design/methodology/approach

Six colored liquid samples with different CDCA contents ranging from 0 to 45 Wt.% have been successfully prepared. Chromaticity (C*), color saturation (s), UV-Vis spectroscopy and coloring strength studies have been assessed to determine how CDCA influences the color properties and to study the color quality over time. The color quality was analyzed using the Commission Internationale de l’Eclairage (CIE) system.

Findings

All results obtained revealed that the addition of CDCA significantly influenced the overall color performance of the saffron extraction. However, the most pronounced improvement was recorded with the use of 45 Wt.% CDCA. The sample exhibited the highest color quality at the end of nine months of storage with highest absorbance: C* value = 91.38, color saturation = 0.96 and coloring strength = 687.

Practical implications

This preliminary study offers significant findings for further research focused on stability of natural colorants extracted from Spanish saffron that can provide benefits for future applications especially in coating industry, food, agriculture, medicine and others.

Originality/value

The values of this work can be observed from the information and evidence provided by CIE color stability in terms of chromaticity and saturation, as well as UV-Vis spectrophotometric measurement. It showed that the addition of CDCA additive can help to prolong and enhance the natural colorant properties from Spanish saffron (Crocus sativus L.) for nine month of storage. This proved that by adding additives such as CDCA the saffron colorant can be maintained. To the best of the authors’ concern, this is the first time CDCA is used to prevent color degradation of natural colorant from saffron.

Details

Pigment & Resin Technology, vol. 47 no. 6
Type: Research Article
ISSN: 0369-9420

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Article

Noraini Mahmad, R.M. Taha, Rashidi Othman, Sakinah Abdullah, Nordiyanah Anuar, Hashimah Elias and Norlina Rawi

The purpose of this paper is to validate the antimicrobial activity (both antibacterial and antifungal) of in vivo and in vitro ethanolic anthocyanin extracts of Clitoria

Abstract

Purpose

The purpose of this paper is to validate the antimicrobial activity (both antibacterial and antifungal) of in vivo and in vitro ethanolic anthocyanin extracts of Clitoria ternatea L. (vivid blue flower butterfly-pea) and Dioscorea alata L. (purple yam) against selected bacteria (Bacillus subtilis, Staphylococcus aureus and Escherichia coli) and fungi (Fusarium sp., Aspergillus niger and Trichoderma sp.).

Design/methodology/approach

The freeze-dried samples (0.2 g) from in vivo vivid blue flowers of C. ternatea L. were extracted using 10 mL ethanol (produced ethanolic red extraction) and 10 mL distilled water (produced aqueous blue extraction) separately. Two-month-old in vitro callus samples (0.2 g) were only extracted using 10 mL ethanol. The anthocyanin extractions were separated with the addition (several times) of ethyl acetate and distilled water (1:2:3) to remove stilbenoids, chlorophyll, less polar flavonoids and other non-polar compounds. Furthermore, the antimicrobial properties were determined using agar diffusion technique. Three bacteria (B. subtilis, S. aureus and E. coli) and fungi (F. sp., A. niger and T. sp.) were streaked on bacteria agar and dextrose agar, respectively, using “hockey stick”. Then, the sterile paper discs (6 mm diameter) were pipetted with 20 µL of 1,010 CFU/mL chloramphenicol (as control for antibacterial) and carbendazim (as control for antifungal) in vivo and in vitro extracts. The plates were incubated at room temperature for 48 h, and the inhibition zones were measured.

Findings

Based on the results, both in vivo and in vitro ethanolic extracts from vivid blue flowers of C. ternatea L. showed the best antibacterial activity against the same bacteria (B. subtilis), 11 and 10 mm inhibition zones, respectively. However, different antifungal activity was detected in in vitro ethanolic callus extract (12 mm), which was against T. sp., contrary to in vivo ethanolic extract (10 mm), which was against F. sp.; antibacterial activity of D. alata L. was seen against the same bacteria (E. coli) with the highest inhibition zone for in vivo extract (8.8 mm), followed by in vitro extract (7.8 mm).

Research limitations/implications

Anthocyanins are responsible for the water soluble and vacuolar, pink, red, purple and blue pigments present in coloured plant pigments. These pigments (pink, red, purple and blue) are of important agronomic value in many crops and ornamental plants. However, anthocyanins are not stable and are easy to degrade and fade whenever exposed to light.

Social implications

Plant extracts containing bioactive agents with antimicrobial properties have been found to be useful in treating bacterial and fungal infections, as well as showed multiple antibiotic resistance.

Originality/value

Both in vivo and in vitro extracts from vivid blue flower petals (C. ternatea L.) and purple yam (D. alata L.) have important applications as natural antimicrobial (antibacterial and antifungal) agents in the coating industry, instead of natural pharmaceutical products.

Details

Pigment & Resin Technology, vol. 47 no. 6
Type: Research Article
ISSN: 0369-9420

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Article

Noraini Mahmad and R.M. Taha

The purpose of this study is to investigate the effects of pH, UV-B radiation and NaCl on anthocyanin extracted from vivid blue petals of Clitoria ternatea L. (legume…

Abstract

Purpose

The purpose of this study is to investigate the effects of pH, UV-B radiation and NaCl on anthocyanin extracted from vivid blue petals of Clitoria ternatea L. (legume crop), as a potential natural colourant for food, dye or coating technology.

Design/methodology/approach

The anthocyanin from petals of Clitoria ternatea was extracted using 0.5 per cent trifluroacetic (TFA) in methanol solution. The liquid colourant was exposed to different pH (1, 4.5 and 5.5), UV-B radiation and sodium chloride (NaCl). The results were compared using UV-vis spectrophotometric analysis.

Findings

Anthocyanins are sensitive and quickly degrade in the presence of light. In the dry powder form, the anthocyanin is easier to maintain and preserve (storage).

Research limitations/implications

Anthocyanins extracted from vivid blue petals of Clitoria ternatea L. are sensitive and quickly degrade in the presence of light.

Practical implications

The anthocyanin pigments extracted from Clitoria ternatea L. petals with methanolic acid were successfully coated on glass slides. The combination of binders and pigments had produced environmental paint which added with stabilisers (additives) for better durability. Acrylic has been known for its high weathering and embrittlement resistance, good mechanical and electrochemical properties and gloss retention.

Social implications

This anthocyanin is suitable as natural colourant especially in baby products, cosmetics production or for coating and varnish application.

Originality/value

Till date, the natural colourant of Clitoria ternatea L. petals is widely used in food. However, this result is a new finding, as there is no report on the potential of applications of this natural colourant for coating technology. Therefore, the current study with appropriate extraction method was significantly based on the relevant literatures of coating production from pigment by using other plant species. The findings and conclusion highlight the practicality as the potential applications in coating technology.

Details

Pigment & Resin Technology, vol. 47 no. 6
Type: Research Article
ISSN: 0369-9420

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Article

Z.H.Z. Abidin, N.N. Naziron, K.M. Nasir, M.S. Rusli, S.V. Lee, M.Z. Kufian, S.R. Majid, B. Vengadaesvaran, A.K. Arof, R.M. Taha and R. Yahya

The purpose of this work is to investigate the influence of curcumin dye natural colorant on adhesion, mechanical, thermal and electrochemical properties of blend poly…

Abstract

Purpose

The purpose of this work is to investigate the influence of curcumin dye natural colorant on adhesion, mechanical, thermal and electrochemical properties of blend poly (methyl methacrylate) (PMMA) – acrylic polyol.

Design/methodology/approach

Extracted curcumin yellow dye colorant from Curcuma Demostica was mixed with PMMA‐acrylic polyol blended polymer in the volume ratios of 9:1, 8:2 and 7:3. The mixtures were applied on pre‐treated cold‐roll mild steel panels. All of the paint coating samples were subjected to potential time measurement (PTM), rapid impact deformation, differential scanning calorimetry (DSC), cross hatch and Fourier transform infrared spectroscopy (FTIR) tests.

Findings

The addition of curcumin dye colorant was able to improve the adhesion, flexibilities and resistance against electrolytes penetration of the blended poly (methyl methacrylate) (PMMA) – acrylic polyol polymer paint system. Cross hatch test studies showed that high amount of curcumin dye colorant (AP30 paint system) had the lowest peel‐off coating area from the substrate. The FTIR test had confirmed the high concentration of hydroxyl group in the AP30 sample. The hydroxyl group was able to promote hydrogen bonding between coating substrate interface. The AP30 sample had the highest coating flexibilities when tested with rapid impact test. This was due to the lowest glass transition value Tg which indicated lowest cross linking density in the coating molecules structure. In the PTM test, AP30 paint system had shown the highest rate electrolytes penetration within the AP sample.

Research limitations/implications

The composition of curcumin dye colorant in the polymer blend is limited from 10 percent to 30 percent pigment volume concentration. Increasing the amount of lawsone pigment will result inhomogeneous mixtures.

Originality/value

The AP paint system is suitable for interior applications. This paint system has to be mixed with suitable additive materials to improve its performance for exterior purpose.

Details

Pigment & Resin Technology, vol. 42 no. 2
Type: Research Article
ISSN: 0369-9420

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Article

Ummi Nur Ain Abdul Razak, R.M. Taha, Siti Aisha Na’illa Che Musa and Normadiha Mohamed

The purpose of this paper is to evaluate the potential of betacyanin pigment extracted from Hylocereus polyrhizus fruit pulp and peel as a natural colorant and to observe…

Abstract

Purpose

The purpose of this paper is to evaluate the potential of betacyanin pigment extracted from Hylocereus polyrhizus fruit pulp and peel as a natural colorant and to observe the effects of pH and light on betacyanin contents.

Design/methodology/approach

In this study, pigment from the pulp and peel of H. polyrhizus fruits was extracted using 80 per cent methanol and 80 per cent acetone. Effects of pH and light exposure during storage on betacyanin content were evaluated. The betacyanin extract, mixed with 20 per cent poly(methyl methacrylate) and coated onto glass slides, was tested with different concentrations of sodium hydroxide (NaCl) to determine its durability. An ultraviolet (UV)–visible spectrophotometer was used for analyzing the betacyanin content.

Findings

Betacyanin pigment extracted from pulp using 80 per cent acetone as the solvent at pH 1.0 had the highest betacyanin content. Betacyanin content decreased when stored under exposure of light compared to storage in dark. In this study, increasing concentration of NaCl decreased the absorbance values at faster rates for betacyanin-coated glass slides.

Research limitations/implications

Acetone is volatile and evaporates rapidly. Pigments extracted with acetone were stored in glass vials which were closed tightly to prevent evaporation.

Social implications

The social implication is the use of natural pigments from cactus species as a valuable and eco-friendly source in a coating system without adverse effects for human health.

Originality/value

The method for detection of stability and effectiveness of betacyanin pigment used as a natural colorant for coating application was beneficial and recent for environment-friendly and natural plant-based product development.

Details

Pigment & Resin Technology, vol. 46 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

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Abstract

Details

Experiencing Persian Heritage
Type: Book
ISBN: 978-1-78754-813-8

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Article

Siti Aisha Na’illa Che Musa, R.M. Taha, Ummi Nur Ain Abdul Razak, Nordiyanah Anuar and A.K. Arof

The purpose of this paper is to evaluate the potential use of natural colorant extracted from fruit flesh and leaves of Cucumis melo L. (C. melo L.) in coating applications.

Abstract

Purpose

The purpose of this paper is to evaluate the potential use of natural colorant extracted from fruit flesh and leaves of Cucumis melo L. (C. melo L.) in coating applications.

Design/methodology/approach

Carotenoids and chlorophylls compounds were extracted from C. melo L. fruit flesh and C. melo L. leaves with the best extraction solvents. Both compounds were tested at various pH for colour stability tests. Then, the most stable pH of both extracts was mixed with 20 per cent poly methyl methacrylate (PMMA) together with tetrahydrofuran and acrylic polyol to form a coating system on glass slides. The coated glass slides were exposed to three different temperatures. The effects of heat on the coated glass slides were evaluated using spectrophotometer at 400-700 nm wavelengths.

Findings

Results revealed that carotenoids extracted from C. melo L. were less stable to be applied in coating applications since the colour degraded in a very short time; however, the chlorophylls extracted were more stable where the colour retained for longer duration.

Originality/value

The method of the plant pigment production of C. melo L. with PMMA was a modified method that could give other various applications as natural product based on plant pigments.

Details

Pigment & Resin Technology, vol. 47 no. 6
Type: Research Article
ISSN: 0369-9420

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Article

Sadegh Mohajer, Rosna Mat Taha, Minoo Mohajer and Nordiyanah Anuar

This study aims to determine the appropriate irradiation dose for induction of somaclonal variation in mass of unorganized parenchyma cells derived from sainfoin …

Abstract

Purpose

This study aims to determine the appropriate irradiation dose for induction of somaclonal variation in mass of unorganized parenchyma cells derived from sainfoin (Onobrychis viciifolia) tissues.

Design/methodology/approach

To investigate the feasibility of UV-B irradiation (312 nm), seeds and callus of sainfoin were exposed to five different intensities (20-100 per cent) for evaluating the effectiveness of phytochemical constituents and cellular behaviour.

Findings

Although percentage of seed viability reduced in 20 per cent intensity of UV-B irradiation compared with control seeds, the germination speed significantly enhanced from 3.58 to 5.42. The spectrophotometer analysis confirmed that concentrations of chlorophyll (a and b) decreased after UV-B exposure as compared with control callus. Also, carotenoid content showed significant differences among treated calli. Flavonoid and phenolic contents were observed to gradually increase when the non-irradiated callus subjected to 40 and 60 per cent intensities of UV-B irradiation, respectively. Observation on cellular behaviour such as determination of nuclear and cell areas, mitotic index and chromosomal aberrations were also detected to change in different intensities of UV-B irradiation. Fragmented and aneuploidy aberrations were only observed in exposed cells with more than 40 per cent intensity of UV-B irradiation.

Originality/value

In reality, radiocytological evaluation was proven to be essential in deducing the effectiveness of UV-B irradiation to induce somaclonal variation in callus tissue of sainfoin.

Details

Pigment & Resin Technology, vol. 47 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

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