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Article
Publication date: 1 September 1973

D.F.G. Pusey

In view of the changes which have taken place in this field in recent years, it is perhaps a suitable time to review the fundamentals of the subject, in order that the…

Abstract

In view of the changes which have taken place in this field in recent years, it is perhaps a suitable time to review the fundamentals of the subject, in order that the significance of recent developments might not be lost for the surface coatings analyst.

Details

Pigment & Resin Technology, vol. 2 no. 9
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 18 October 2018

Hashimah Elias, Rosna Mat Taha, Nor Azlina Hasbullah, Rashidi Othman, Noraini Mahmad, Azani Saleh and Sakinah Abdullah

This paper aims to study the effect of different organic solvents on the extraction of pigments present in callus cultures of E. cinerascens.

Abstract

Purpose

This paper aims to study the effect of different organic solvents on the extraction of pigments present in callus cultures of E. cinerascens.

Design/methodology/approach

Attempts have been made to extract pigments from callus cultures through tissue culture system as an alternative replacement for conventional plant cultivation as tissue culture provides unlimited supplies of plant samples. Callus of E. cinerascens was induced from stem explant cultured in Murashige and Skoog medium supplemented with combination of 0.5 mg/L 6-benzylaminopurine and 0.5 mg/L α-naphthaleneacetic acid maintained under photoperiod of 16 h light and 8 h dark. Fresh samples of the callus were harvested and dissolved in various types and concentrations of solvents such as 100 per cent acetone, 80 per cent acetone, 95 per cent ethanol, 100 per cent methanol and 90 per cent methanol. Each of the mixtures was directly centrifuged to get clear supernatant containing pigments of interest. The pigments were detected and subsequently quantified via two simple techniques, ultraviolet-visible (UV-Vis) spectrophotometer and thin layer chromatography (TLC).

Findings

UV-Vis spectrophotometer detected two families of pigments present in the callus cultures, namely, carotenoids (carotene and xanthophyll) and tetrapyrroles (chlorophyll a and b). Pigment contents in various solvent extractions were estimated using spectroscopic quantification equations established. Through TLC, spots were seen on the plates, and Rf values of each spots were assessed to indicate the possible existence of carotenoids and tetrapyrroles.

Originality/value

This preliminary study offers significant finding for further advance research related on natural pigments extracted from E. cinerascens that would provide profits in the future applications, especially in food industry, medicine, agriculture, etc.

Details

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

Keywords

Article
Publication date: 1 November 2018

Snehal Patel and Vinit Patel

Polyphenols possess anti-allergic activities. Catechin is one of the polyphenols that are abundantly present in the Acacia catechu. In this study, the authors investigated the…

Abstract

Purpose

Polyphenols possess anti-allergic activities. Catechin is one of the polyphenols that are abundantly present in the Acacia catechu. In this study, the authors investigated the effect of catechin isolated from A. catechu in an experimental mouse model of ovalbumin (OVA)-induced allergic asthma.

Design/methodology/approach

Catechin was isolated from A. catechu, and phytochemical analysis was carried out by ultraviolet visible and thin-layer chromatography (TLC), high pressure thin-layer chromatography was used for the determination of an amount of catechin present. In a first set of an experiment, the authors have carried out dose-dependent evaluation of catechin on histamine synthesis in normal rats. In another study, allergic asthma was induced in BALB/c mice by intraperitoneal injection of 50 mg OVA dissolved in 4 mg aluminum hydroxide dissolved in 0.2 ml saline on Days 0 and 14. Catechin was given orally at the dose of 100 mg/kg, once a day from Day 1 to Day 35 and after which various respiratory parameters such as tidal volume, respiratory rate and airflow rate, biochemical parameters such as histamine release from mast cells, bronchoalveolar (BAL) lavage fluid analysis and histopathology of lungs were carried out.

Findings

Catechin showed significant (p < 0.05) improvement in respiratory parameters such as tidal volume, respiratory rate and airflow rate, as well as biochemical and hematological parameters such as blood histamine, serum bicarbonate and nitric oxide levels as compared to the disease control group. The treatment also showed inhibitory effects on histamine synthesis in rat peritoneal as well as BAL mast cells. Also, a significant (p < 0.05) improvement in lung histopathology was observed with catechin.

Originality/value

From the present study, the authors can conclude that catechin exhibited potent anti-allergic activity by inhibition of histamine synthesis by inhibition of histidine decarboxylase enzyme. The study suggests that catechin has therapeutic potential for the treatment of allergic inflammatory disease in humans.

Details

Nutrition & Food Science, vol. 49 no. 1
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 25 June 2019

Ankit Chokriwal, Bjorn John Stephen and Abhijeet Singh

Carotenoids are pigments that have significant value as colorants and antioxidants in pharmaceutical, food, textile and cosmetic industries. Owing to its high demand, this study…

Abstract

Purpose

Carotenoids are pigments that have significant value as colorants and antioxidants in pharmaceutical, food, textile and cosmetic industries. Owing to its high demand, this study aims to identify ß-carotene producing bacteria from different terrestrial habitats of Jaipur region.

Design/methodology/approach

In this paper, standard isolation and purification process was used, followed by colony morphology and biochemical characterization of ß-carotene producing bacteria. ß-carotene concentration was determined quantitatively using spectrophotometric method.

Findings

Out of 43 isolates, 21 isolates showed peak range between 400 and 500 nm confirming the presence of carotenoids. Only one bacteria SAN-A has capacity to produce ß-carotene confirmed by the thin layer chromatography and high performance liquid chromatography (HPLC) with a yield of 1.68 mg/l. The 2, 2-Diphenyl-2-picrylhydrazil (DPPH) assay showed an IC50 value of 4.0 mg/ml.

Originality/value

The present study revealed the presence of ß-carotene producing bacteria in the soil of different terrestrial habitat of Jaipur region which can be exploited as an economical source for ß-carotene production.

Details

Pigment & Resin Technology, vol. 48 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Open Access
Article
Publication date: 3 June 2019

Lutendo Patricia Mathivha, Vuyisile Samuel Thibane and Fhatuwani Nixwell Mudau

The purpose of this paper is to investigate the health and medicinal importance of bush tea (Athrixia phylicoides DC) and special tea (Monsonia burkeana Planch. ex Harv), two of…

1997

Abstract

Purpose

The purpose of this paper is to investigate the health and medicinal importance of bush tea (Athrixia phylicoides DC) and special tea (Monsonia burkeana Planch. ex Harv), two of Southern African indigenous herbal teas.

Design/methodology/approach

The two herbal teas, A. phylicoides and M. burkeana were extracted individually and in combined ratios for analysis. The phenolic content was determined and the different phenolic compounds were identified using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). The anti-diabetic activity of the teas was determined by evaluating the inhibition of both α-amylase and α-glucosidase in vitro. The anti-proliferative activity was measured on human cervical cancer (HeLa) cell line using the MTT (3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium) assay.

Findings

Gallic acid, chlorogenic acid and quercetin were identified to be present in significant quantities by TLC. The HPLC quantified the presence of catechin (1.567 mg/g) and chlorogenic acid (1.862 mg/g) in special tea while chlorogenic acid (1.288 mg/g) was present in bush tea. Bush tea and special tea expressed significant levels of phenolic content and high antioxidant activities. Special tea (S100) expressed high inhibition of α-amylase, α-glucosidase and HeLa cell line proliferation when compared to bush tea (B100).

Originality/value

Both bush tea and special tea could provide an alternative for treatment and management of both diabetes and cervical cancer. However, future studies are needed to investigate their synergistic effect with a wide range of other commercial herbal teas.

Details

British Food Journal, vol. 121 no. 4
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 24 July 2007

Choong Yew Keong, Badrul Amini Abdul Rashid, Young Swee Ing and Zakiah Ismail

The aim of this study is to identify and quantify sugar and polysaccharide contents in locally grown Hericium erinaceus.

1515

Abstract

Purpose

The aim of this study is to identify and quantify sugar and polysaccharide contents in locally grown Hericium erinaceus.

Desig/methodolog/approach

The experiment is presented of chromatography methods to determine sugars in Malaysian–grown H. erinaceus. After the extraction, the crude polysaccharide solution was followed by hydrolysis with acid as well as enzymes reaction, respectively.

Findings

In thinlayer chromatography, two sample spots turned blue after treatment with sugar visualizing reagent. The HPLC analysis of the H. erinaceus hot water crude extract showed arabinose as the major component. All H. erinaceus water crude extract showed the components of arabinose, glucose and rhamnose when reacting with different enzymes. The ratio of arabinose and glucose was 2.3:1 after enzymatic reaction compared with 2.7:1 before the enzymatic reaction.

Research limitation/implications

The H. erinaceus polysaccharides from the fruiting body can be further isolated and purified by means of GCMS. In this way, the contents of the polysaccharides isolated and types of the linkage can be determined thoroughly in a more detailed way. The purified polysaccharides also should be screened for the bioassay guide fractionation.

Practical implications

The H. erinaceus can also be analyzed for its various nutritional values. In this way, it is hoped that Malaysia can produce Hericium products locally for the benefit of the local consumers with a more competitive price.

Originalit/value

This paper fulfils an identified information of sugar and polysaccharide content in Malaysian–grown H. erinaceus.

Details

Nutrition & Food Science, vol. 37 no. 4
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 1 April 1976

G.M. STANTON

It often becomes necessary to analyse a grease for a variety of reasons:

Abstract

It often becomes necessary to analyse a grease for a variety of reasons:

Details

Industrial Lubrication and Tribology, vol. 28 no. 4
Type: Research Article
ISSN: 0036-8792

Article
Publication date: 20 September 2019

Zeng Huawei, Wang Chengtao, Qiao Jie, Zhang Bingjing, Zhao Bing and Dai Chuangyun

The Monascus pigment has been widely applied in the food processing industry as a functional additive. Lovastatin and polysaccharides are two important bio-active materials found…

Abstract

Purpose

The Monascus pigment has been widely applied in the food processing industry as a functional additive. Lovastatin and polysaccharides are two important bio-active materials found in Monascus. Citrinin is considered as mycotoxin. Thus, it is important to produce high yields of intracellular Monascus pigments with high yields of lovastatin and polysaccharides, while maintaining low citrinin yields under liquid fermentation.

Design/methodology/approach

The intracellular yields of pigments, lovastatin, polysaccharides and citrinin; biomass; and reducing the sugar content of Monascus purpureus HBSD 08 were determined every day during a 10-day culturing period using lactose, maltose, sucrose, glucose, glycerine and xylose as the sole carbon sources. Additionally, the pigment composition was analysed by a thin layer chromatography (TLC) and the in vitro antitumor activities of the pigments were determined.

Findings

The maximal yield of pigments (55.44 U/mL after six days of culture) and lovastatin content (1,475.30 µg/L after five days of culture) were obtained in the presence of glucose and maltose as the sole carbon sources, respectively. The suitable carbon sources for high intracellular polysaccharides yields were sucrose, maltose and xylose. Glucose should not be chosen as the sole carbon source because of its high food safety risk. In vitro antitumor activities of pigments in the presence of different carbon sources were in the order of xylose > glucose = maltose > glycerine > sucrose = lactose. The pigment compositions in the presence of different carbon sources were the same from the TLC analysis. Thus, maltose displayed high intracellular yields of pigments, lovastatin and polysaccharides; high food safety against citrinin, and high in vitro antitumor activity during the ten days culturing period.

Originality/value

This study shows us the benefits of using maltose as a substrate in the production of intracellular Monascus pigments while ensuring economic and food safety.

Details

Pigment & Resin Technology, vol. 48 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 15 November 2018

Huawei Zeng, Qiao Jie, Zeng Xin, Xu Dayong, Xiong Minghua, Li Feng, Sun Jianfan, Jiang Xuan and Dai Chuanyun

Monascus pigment was widely applied in food processing industry as functional additive, so more attention was paid to the fermentation optimization of pigment production…

Abstract

Purpose

Monascus pigment was widely applied in food processing industry as functional additive, so more attention was paid to the fermentation optimization of pigment production. Therefore, this paper aims to evaluate the best possible fermentative conditions for maximum production of biopigment using submerged fermentation (SFM) and solid state fermentation (SSF) by Monascus purpureus HBSD 08.

Design/methodology/approach

The biopigment was produced by using an SMF and an SSF with optimized substrate to achieve higher yield. The antioxidant activity was evaluated by DPPH radical scavenging ability, superoxide anion radical scavenging ability and hydroxyl radical scavenging ability. The pigment composition was analyzed by thin layer chromatography.

Findings

Maximum Monascus pigment production (79.6 U/ml and 1,102 U/g) were obtained under an SFM and an SFF. The antioxidant activity of the pigment in an SFM was significantly higher than that in an SFM. The composition of pigment was not different in an SFM and an SFF.

Originality/value

The study developed new conditions, and Monascus strain was a candidate for producing pigment in an SFM and an SFF. To the authors’ best knowledge, this is a first attempt toward comparative evaluation on antioxidant capacity and composition between pigment in an SSF and an SFM. This result will serve for Monascus pigment production.

Article
Publication date: 27 September 2023

Siddhesh Umesh Mestry, Vardhan B. Satalkar and S.T. Mhaske

This study aims to describe the design and synthesis of two novel azo and imine chromophores-based dyes derived from two different aldehydes with intramolecular colour matching…

Abstract

Purpose

This study aims to describe the design and synthesis of two novel azo and imine chromophores-based dyes derived from two different aldehydes with intramolecular colour matching that are pH sensitive.

Design/methodology/approach

The visible absorption wavelength (λmax) was extended when azo chromophore was included in imine-based systems. The dyed patterns created sophisticated colour-changing paper packaging sensors with pH-sensitive chromophores using alum as a mediator or mordant. Due to the tight adhesive bonding, the dyes on paper’s cellulose fibres could not be removed by ordinary water even at extremely high or low pH, which was confirmed by scanning electron microscopy analysis. The dyed patterns demonstrated an evident, sensitive and fast colour-changing mechanism with varying pH, from pale yellow to red for Dye-I and from pale yellow to brown-violet for Dye-II.

Findings

The λmax for colour changing was recorded from 400 to 490 nm for Dye-I, whereas from 400 to 520 for Dye-II. The freshness judgement of food was checked using actual experiments with cooked crab spoilage, where the cooked crab was incubated at 37 oC for 6 h to see the noticeable colour change from yellow to brown-violet with Dye-II. The colour-changing mechanism was studied with Fourier transform infrared (FTIR) spectra at different pH, and thin layer chromatography, nuclear magnetic resonance and FTIR spectroscopy studied the desired structure formation of the dyes. Potential uses for smart packaging sensors include quickly detecting food freshness during transportation or right before consumption.

Originality/value

1. Two novel azo-imine dyes have been synthesized with a pH-responsive effect. 2. The pH-responsive mechanism was studied. 3. The study was supported by computational chemistry using density functional theory. 4. The obtained dyes were used to make pH-responsive sensors for seafood packaging to judge the freshness.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

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