Bleaching Activity Research Articles

Review of Bleach Activators for Environmentally Efficient Bleaching of Textiles

Textile wet processing is the most polluting aspect of textile manufacturing and contributes to the global textile industry’s substantial carbon footprint. Textile preparation of cotton typically includes scouring and bleaching at high temperature and high pH. Substantial amounts of wastewater are produced that must be treated prior to being released to receiving fresh water. Recent research in our laboratories has focused on the development and application of compounds that enhance the bleaching process. We have developed novel cationic bleach activators that can be used to bleach cellulosic fabrics and flber blends at reduced temperature, pH, and time. Results show that after optimization equivalent or improved performance in whiteness, absorbency and strength are possible relative to conventional bleaching methods. One of the most promising bleach activators to date is N-[4-(Triethylammoniomethyl) Benzoyl]-Butyrolactam Chloride (TBBC). TBBC was designed in our group to a) exhibit strong oxidation potential when activated; b) have reasonable hydrolytic stability; and c) be inherently substantive towards cellulosic and other flbers. In this paper, we review the development of bleach activators for textile bleaching, and discuss the opportunities and potential hurdles involved in commercialization of bleach activators for textile wet processing.

Cytotoxic, apoptotic and anti-α-glucosidase activities of 3,4-di-O-caffeoyl quinic acid, an antioxidant isolated from the polyphenolic-rich extract of Elephantopus mollis Kunth.

The decoction of the whole plant of Elephantopus mollis Kunth. is traditionally consumed to treat various free radical-mediated diseases including cancer and diabetes. This study was initiated to determine whether the most effective antioxidant compound isolated from the whole plant of Elephantopus mollis can also contribute to its claimed traditional values as anticancer and antidiabetes agents. An active antiradical phenolic compound (3,4-di-O-caffeoyl quinic acid) was isolated from the methanol extract (with the highest in polyphenolic content) and their antioxidant activities were compared using four different assays, that are DPPH, FRAP, metal chelating, and β-carotene bleaching tests. The compound was also evaluated for its cytotoxic activity, apoptotic induction and anti-glucosidase efficacies using methylene blue, DeadEnd™ assay and α-glucosidase assays, respectively. The compound acted as a greater primary antioxidant than its methanol extract, by having higher ferric reducing activity (EC(50) 2.18±0.05 μg/ml), β-carotene bleaching activity (EC(50) 23.85±0.65 μg/ml) and DPPH scavenging activity (EC(50) 68.91±5.44μg/ml), whereas the methanol extract exhibited higher secondary antioxidant activity as a metal chelator with lower EC(50) value (49.39±3.68 μg/ml) than the compound. Cytotoxicity screening of this compound exhibited a remarkable dose-dependent inhibitory effect on NCI-H23 (human lung adenocarcinoma) cell lines (EC(50) 3.26±0.35 μg/ml) and was found to be apoptotic in nature based on a clear indication of DNA fragmentation. This compound also displayed a concentration-dependent α-glucosidase inhibition with EC(50) 241.80±14.29 μg/ml. The findings indicate the major role of 3,4-di-O-caffeoyl quinic acid to antioxidant capacities of Elephantopus mollis extracts. The compound also exerted apoptosis-mediated cytotoxicity and α-glucosidase inhibitory effects and is thus a promising non toxic agent in treating cancer and type 2 diabetes mellitus.

One-copper laccase-related enzyme from Marasmius sp.: Purification, characterization and bleaching of textile dyes

In the culture filtrate of a Marasmius sp. strain isolated in Indonesia during a screening for fungi with the ability to decolorize textile dyes, two laccase-related enzymes (laccase-related enzyme I and II) were detected. Laccase-related enzyme I was purified to homogeneity by ion exchange and hydrophobic interaction chromatography. The native enzyme was shown to have a molecular mass of 53kDa, an N-terminal amino acid sequence characteristically seen in laccases and an isoelectric point of pH 3.8. The enzyme accepts typical laccase substrates including 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), syringaldazine and guaiacol, but has no tyrosinase activity. The pH optimum is at pH 3.0 for ABTS and at 6.0 for syringaldazine and the enzyme is stable up to pH 10. The UV/vis spectrum of the laccase-related enzyme is non-typical for laccases and metal content analysis revealed that the enzyme contains only a single copper atom per enzyme molecule. This suggests that this enzyme could be related to the group of the so-called “white” laccases, however, no zinc or any other metal ion could be detected in this enzyme, suggesting that the enzyme is a unique laccase-related enzyme. Comparison of the bleaching activity of the whole fungus with that of the isolated laccase-related enzyme showed that this enzyme is the major bleaching enzyme produced by this Marasmius sp. strain and was able to bleach violet, red, orange and yellow dyes in addition to a number of blue dyes.

Evaluation of antioxidant and DNA protection activities in the extracts of the Terminalia catappa leaves

Terminalia catappa (Combretaceae) is used commonly as a folk medicine in Taiwan, and has been claimed to have therapeutic effects in hepatitis and liver related diseases [1, 2]. The leaves, bark and fruit of the Terminalia catappa have also been commonly used as a folk medicine for antidiarrheic, antipyretic and haemostatic purposes in India, Philippines, Malaysia and Indonesia [3]. The extracts from the Terminalia catappa leaves were used in this study. Antioxidant activities were measured by both 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH·) scavenging and 2, 2-azino-bis (3-ethylbenz- thiazoline-6-sulfonic acid) (ABTS·+) decolourisation methods. To further evaluate the effect of Terminalia catappa extracts on UV induced DNA damages, the DNA protection assay was employed. Terminalia catappa leaf extracts had effective DPPH bleaching activity and ABTS·+ radical scavenging activity in a concentration dependent manner. Furthermore, the Terminalia catappa leaf extracts to inhibit the oxidative DNA damages were assessed by measuring the conversion of supercoiled pUC119 plasmid DNA to the linear forms. UV irradiation of DNA with hydrogen peroxide resulted in the formation of linear forms of DNA, indicating double-strand DNA breaks. Addition of Terminalia catappa plant extracts to DNA resulted in a partial inhibition of the conversion of supercoiled DNA to linear forms, indicating that the Terminalia catappa plant extract was able to protect plasmid DNA against hydroxyl radical induced oxidative damage. The inhibition of hydroxyl radical induced DNA strand breaks by Terminalia catappa plant extracts exhibited a concentration dependent relationship.

Carotenoids and antioxidant capacities from Canarium odontophyllum Miq. fruit

Carotenoids were isolated and identified from peel, pulp and seed fractions of Canarium odontophyllum Miq., and their antioxidant capacities were evaluated. all- trans-β-carotene was present in a large amount in peel (69.5 ± 1.0 mg/kg), followed by pulp (31.1 ± 0.76 mg/kg) and seed (15.1 ± 3.0 mg/kg). Additionally, 15- cis-β-carotene, 9- cis-β-carotene and 13- cis-β-carotenes were also major contributors to carotenoid contents in peel, pulp and seed fractions. Pulp exhibited excellent β-carotene bleaching activity, significantly higher than peel and seed; high 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, whereas peel exhibited significantly higher scavenging activity of 2,2’-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radicals. All the extracts exhibited good inhibitory effect against hydrogen peroxide-induced haemoglobin oxidation, ranging from 45.3 to 59.7%. This is the first report about carotenoids and antioxidant capacities from C. odontophyllum fruit, and indicates that this fruit can be explored and promoted as a potential source of natural antioxidants.

땅콩나물 추출물의 항산화 효과

For the long-term goal of using peanut sprouts as a functional food material, the total polyphenol content and the antioxidant activity of methanol extracts were examined with use of 9 day-old peanut sprouts and peanuts collected in Chungbuk, Gyeongbuk and Jeonbuk provinces of Korea, China and Vietnam. The polyphenol levels in the sprout extracts were higher than those of the peanut extracts. The phenolic content of the Gyeongbuk peanut sprout extract (20.4 ㎎/g) was the highest of the tested samples. After 9 days of germination the peanut sprout extracts had higher activities than those of the peanut extracts. In particular, the activity of Gyeongbuk peanut sprout extract was the highest (37.67% at a concentration of 200 ㎕/㎖), and its reducing power demonstrated a similar trend. The DPPH radical scavenging activities were measured for methanol extracts of cotyledon, root and stem of Gyeongbuk peanut sprouts; the highest (90.96% at a concentration of 200 ㎕/㎖) was the activity of cotyledon. ABTS radical scavenging and β-carotene bleaching activities also were higher in the cotyledon extract than in those of the root or the stem. The resveratrol content was higher in the Gyeongbuk peanut sprout extract than in the Gyeongbuk peanut extract (15.05 ㎍/g and 1.42 ㎍/g, respectively). These results suggest that peanut sprouts potentially could be used as a functional food material exhibiting antioxidant effects.

Bleaching cellulosic fibers via pre-sorption of N-[4-(triethylammoniomethyl)-benzoyl]-butyrolactam chloride

The sorption of a novel cationic bleach activator, N-[4-(Triethylammoniomethyl)benzoyl]-butyrolactam Chloride (TBBC), was measured on regenerated bamboo fiber. At 25 °C near neutral pH, the sorption rate of TBBC onto the fiber was initially rapid and equilibrium was reached within 20 min. Adsorption equilibria experiments followed a Freundlich isotherm. At the sorption equilibrium, bleaching was initiated by addition of sodium perborate to liberate hydrogen peroxide, which reacted with TBBC to generate a peracid that is a more kinetically active oxidant than peroxide. A sorption–activation model was developed that supports the enhanced bleaching of cellulosic fibers using cationic bleach activators under neutral to alkaline conditions.

Changes in colour and antioxidant activities of Hizikia fusiformis cooking drips by gamma irradiation

To utilize the cooking drips produced during the seaweed drying process, the effect of gamma irradiation on microbial contamination, colour, and antioxidant activities of Hizikia fusiformis cooking drips (HCD) was investigated. A two log cycles reduction of total aerobic bacteria and yeast and moulds counts was obtained irradiating HCD at 1 kGy. The Hunter L ∗ value of the HCD ethanol extract was increased by the gamma irradiation treatment, but the a ∗ and b ∗ values decreased upon irradiation depending on the absorbed dose. The 1,1-diphenyl-2-picrylhydrazyl radical scavenging and β-carotene bleaching activities of the HCD extracts increased as a result of gamma irradiation, which was rationalized by the observed increase in polyphenolic compounds content. These results suggest that wasted cooking drips can be used as a functional component by the food and cosmetic industries if the irradiation technology were applied.

Activated peroxide bleaching of regenerated bamboo fiber using a butyrolactam-based cationic bleach activator

Regenerated bamboo fibers are potentially a valuable source of renewable fibers for use in a wide variety of applications. As with almost all natural fibers, inherent yellowness must be reduced or eliminated in order for the fibers to be used effectively in processes such as dyeing. Oxidative bleaching in the form of hot alkaline hydrogen peroxide is the most common method for bleaching cellulosic fibers. However, significant fiber damage results, especially in the case of regenerated bamboo. Recently, more benign oxidative bleaching methods have been developed using so-called bleach activators. Reported is an effective bleaching method using a novel bleach activator, N-[4-(triethylammoniomethyl)benzoyl]butyrolactam chloride (TBBC). The ratio of TBBC to hydrogen peroxide and pH were found to be critical to achieving effective bleaching at low temperature. Using equimolar amounts of TBBC and hydrogen peroxide at pH 7 and 50 °C, comparable whiteness and less fiber damage compared with conventional peroxide bleaching was obtained. However, at pH 11.5, TBBC had no effect on whiteness.

Hydrolytic stability of a series of lactam-based cationic bleach activators and their impact on cellulose peroxide bleaching

A series of five cationic bleach activators containing lactam-based leaving groups of varying ring size was synthesized and characterized. The hydrolytic stability of each activator was determined via HPLC-based analysis of hydrolysis products, titration of available oxygen, and whiteness assessment of cellulosic fibers using a peroxide-activator bleaching system following solution storage for various times under controlled conditions. Aqueous alkaline solutions of each activator hydrolysed at different rates with the slowest rates observed with the ω-octalactam ring system, the largest ring size investigated, and the most rapid hydrolysis was found with a six-membered lactam ring based activator. The whiteness of cotton bleached with stored bleach activator solutions inversely correlated with the hydrolysis rate for each activator. The hydrolysis rate followed pseudo first order kinetics.

Effects of Bleach Activator, Sodium Alkyl Acyloxybenzene Sulfonate, on House Dust Mites (Dermatophagoides farinae)

House dust mites (Dermatophagoides farinae) in bedding and clothes are a major allergen. However, house dust mites cannot be killed by general washing conditions under 50 degrees C. Therefore, low-temperature washing conditions must be improved to eliminate house dust mites. Sodium alkyl acyloxybenzene sulfonate (OBS) is a bleach activator that is used to intensify the bleaching effects of some laundry products. The purpose of this study was to evaluate the effect of OBS on the elimination of house dust mites in low-temperature washing conditions. D. farinae was soaked in solutions containing different types of OBS for various durations and at various temperatures. The miticidal effects of the various washing conditions were also evaluated for D. farinae. Then sodium lauroyloxybenzene sulfonate (OBS-12) produced the highest D. farinae mortality rate among the OBS solutions that were examined and had a stronger miticidal effect than available chlorine under general washing conditions. OBS exhibited miticidal effects under general washing conditions at low temperatures. Since OBS is already used as an additive in some laundry products to increase the bleaching activity, OBS can be easily used to kill house dust mites under general washing conditions.

Antioxidant capacity and phenolic acids of virgin coconut oil

The antioxidant properties of virgin coconut oil produced through chilling and fermentation were investigated and compared with refined, bleached and deodorized coconut oil. Virgin coconut oil showed better antioxidant capacity than refined, bleached and deodorized coconut oil. The virgin coconut oil produced through the fermentation method had the strongest scavenging effect on 1,1-diphenyl-2-picrylhydrazyl and the highest antioxidant activity based on the β-carotene–linoleate bleaching method. However, virgin coconut oil obtained through the chilling method had the highest reducing power. The major phenolic acids detected were ferulic acid and p-coumaric acid. Very high correlations were found between the total phenolic content and scavenging activity (r=0.91), and between the total phenolic content and reducing power (r=0.96). There was also a high correlation between total phenolic acids and β-carotene bleaching activity. The study indicated that the contribution of antioxidant capacity in virgin coconut oil could be due to phenolic compounds.

ENAMEL MICROHARDNESS AFTER APPLICATION OF 30% CARBAMIDE PEROXIDE AND SUBSEQUENTLY AFTER APPLICATION OF FLUORIDE

Thirty percent carbamide peroxide is widely used as in extra-coronal bleaching method. Its current effect on enamel (e.g. enamel microhardness) is still uncertain. In dentistry, fluoride is recommended to be applied in 60 seconds. The aim of this study is to observe the effect of 30% carbamide peroxide on enamel microhardness and also the effect of fluoride application on enamel microhardness that changed upon bleaching activity within shorter period than time of application recommended (30 seconds), in recommended period of application (60 seconds), and in a longer period of 90 seconds. Thirty extracted teeth were bleached with 30% carbamide peroxide for 1 hour, and the enamel microhardness was measured by Knoop method. The microhardness of enamel was also evaluated soon after application of fluoride to the bleached tooth and after fluoride application and immersion in artificial saliva for one hour. It was revealed that the microhardness of normal enamel was 360,46 KHN and decreased significantly to 170,33 KHN (57%) after application of 30% carbamide peroxide. Soon after application of fluoride there was an increase in enamel microhardness although not significant on all duration of application. After application of fluoride and one hour immersion in saliva, the enamel microhardness increases significantly, especially in duration of fluoride and one hour immersion in saliva, the enamel microhardness increased significantly, especially in duration of fluoride application longer than recommended (90 seconds). Based on data above, it can be concluded that there was a 57% decrease in enamel hardness after application of 30% carbamide peroxide and this enamel microhardness increased after application of fluoride and after immersion in artificial saliva.

참치 자숙액의 항산화 활성에 감마선 조사가 미치는 영향

Division of Food Beverage and Culinary Art, Yeungnam College of Science and Technology, Daegu 705-703, KoreaAbstractThis study was conducted to examine the effect of a gamma irradiation on the antioxidant activity of ethanol extract from cooking drips of Thunnus thynnus (ECT). The electron donating ability against 1,1-diphenyl- 2-picryl-hydrazyl (DPPH), authentic hydroxyl radical scavenging activity by Ultra Weak Luminescence Analyzer, oxidative protection factors by Racimat method, ferric reducing antioxidant power (FRAP), and β-carotene bleaching activity were measured as indices of antioxidant activity. All of the results shown that irradiation increased the antioxidant activity of ECT. These results suggested that ECT could be used as an antioxidative component in food and gamma irradiation could enhance these antioxidative properties.Key words: cooking drips, Thunnus thynnus, antioxidant activity, gamma irradiation

Distribution along durum wheat kernel of the components involved in semolina colour

A bright yellow colour of pasta is an important qualitative trait for the durum wheat industry. Final colour is the result of the balance between yellow and brown components in semolina. Carotenoid pigments and lipoxygenase (LOX) enzyme are mainly involved in yellowness, whereas peroxidase (POD) and ash affect brown hue. All these components have a different distribution across the kernel, with varietal differences too. This study aimed to evaluate the distribution pattern of carotenoid pigments, α-tocopherol, linoleic acid, and ash content as well as of LOX and POD activities within the kernel of six durum wheat cultivars characterised by different pigment content and hydroperoxidation activity of LOX in semolina. The results confirmed differences in the distribution of these components across the kernel and among varieties. Additionally, this study identified for some components (POD, pigments and bleaching activity of LOX) a higher effect of genotype whereas for others (ash, α-tocopherol, hydroperoxidation activity) a marked effect of the debranning process. These results suggest that improvement of the final semolina colour could be reached both through breeding activity, enabling an early selection of better lines, and through an appropriate debranning process.

Enhanced PAA bleaching of cotton by incorporating a cationic bleach activator

Peracetic acid is a well‐known alternative to hydrogen peroxide as a bleaching agent for cotton. In this study, a novel cationic bleach activator, N‐[4‐(triethylammoniomethyl)benzoyl]butyrolactam chloride, was used in combination with peracetic acid to investigate the enhancement of cotton bleaching efficiency. The effects of temperature, pH and concentrations of activator and peracetic acid on the bleaching performance were studied using a statistical design of experiment. Adding activator to a peracetic acid bleaching bath improved the resultant whiteness of the substrate and at optimal conditions produced less fibre damage than when peracetic acid was used alone. In addition, the bleaching performance of both peracetic acid and hydrogen peroxide in the presence of activator was compared. In the absence of activator, the peracetic acid performance was considerably superior to a conventional hydrogen peroxide bleach system in which no bleach activator is present. However, addition of activator to the hydrogen peroxide bath increased the whiteness to a level comparable to peracetic acid.

Development of in vitro tooth staining model and usage of catalysts to elevate the effectiveness of tooth bleaching

Objectives Whole blood or tea was frequently used to stain the teeth for measuring the effectiveness of different bleaching materials. However, the components of blood or tea cannot be quantitatively determined and variability might exist among different brands of tea. The purpose of this study was to develop a reproducible in vitro tooth-staining model to simulate the intrinsic discoloration of teeth and evaluate the ability of two catalysts to enhance the bleaching activity of H 2O 2. Methods Rhodamine B, Orange II, Fe(III) phthalocyanine, and tea were used to stain the tooth specimens for 4–72 h and subsequently bleached by H 2O 2 for 4–72 h. The process was photographed using a digital stereoscopic microscope and a digital camera. The image was transformed to get L *, a *, b * values of CIE Lab system with image processing software. The catalytic ability of light irradiation plus addition of Fe/Sodium-Y or Mn/Sodium-Y for specimens stained by Orange II was evaluated in test tubes and in extracted tooth model. Results The color of specimens stained by Rhodamine B could not be sufficiently recovered after bleaching by H 2O 2. In addition, the reaction of Fe(III) phthalocyanine with H 2O 2 in test tubes was too fast to be monitored. Light activation plus use of Fe/Sodium-Y or Mn/Sodium-Y could significantly accelerate the bleaching efficiency of H 2O 2. Significance Orange II was the most appropriate dye for tooth staining among the dyes used in this study. Addition of Fe/Sodium-Y or Mn/Sodium-Y plus light irradiation could elevate the bleaching efficacy of H 2O 2 for those specimens stained by Orange II.

Antioxidant and antibacterial activity of leaves of Etlingera species (Zingiberaceae) in Peninsular Malaysia

Methanolic extracts from fresh leaves of five Etlingera species were screened for total phenolic content (TPC), antioxidant activity (AOA), and antibacterial activity. Analysis of TPC was done using the Folin–Ciocalteu method. Evaluations of AOA included 1,1-diphenyl-2-picrylhydrazyl free radical-scavenging ability, ferric-reducing antioxidant power (FRAP), ferrous-ion chelating (FIC) ability, and β-carotene bleaching (BCB) activity. Antibacterial activity was screened using the disc-diffusion method. Highest TPC, ascorbic acid equivalent antioxidant capacity (AEAC), and FRAP were found in leaves of E. elatior and E. rubrostriata. Leaves of E. maingayi, with the lowest TPC, AEAC, and FRAP, had the highest FIC ability and BCB activity. Ranking of TPC and AOA of different plant parts of E. elatior was in the order: leaves > inflorescences > rhizomes. Leaves of highland populations of Etlingera species displayed higher values of TPC and AEAC than those of lowland counterparts. Leaves of Etlingera species exhibited antibacterial activity against Gram-positive but not Gram-negative bacteria.

Investigations into the efficacy of methyhlphosphonic acid functionalised 1,4,7-triazacyclononane ligands in bleaching catalysis

In an attempt to reduce the dye and fabric damage caused by manganese complexes of 1,4,7-trimethyl-1,4,7-triazacyclononane previously employed as low temperature bleaching catalysts in domestic laundry formulations, a novel series of analogues with chelating phosphonic acid pendant arms has been prepared. In order to identify possible bleaching catalysts more rapidly, and with reduced environmental impact, a bleaching screening test has been developed that seeks to identify metal–ligand combinations that may represent active low temperature bleaching catalysts. Of the four methylphosphonic acid containing ligands tested in combination with a range of transition metal salts, only two metal–ligand combinations with manganese salts displayed sufficient activity to take forward for further testing, with the efficacy of the ligands in the oxidative removal of stains decreasing as the number of pendant arms increased. Both of the active ligand systems produced greater dye damage than existing bleach activators, with the ligand with a single methylphosphonic acid pendant arm being particularly aggressive towards stained fabrics sensitive to oxidative damage. This indicates that the systematic addition of chelating pendant arms, whilst tempering the activity of the complexes as bleaching catalysts, unfortunately does not provide a solution to the problem of dye and fabric damage. In contrast to the activity observed in the bleaching screen, the activity of the manganese–ligand combinations in the epoxidation of some alkene substrates was found to bear no relation to the number of methylphosphonic acid pendant arms.

Evidence for a radical mechanism in biocatalytic degradation of synthetic dyes by fungal laccases mediated by violuric acid

The bleaching activity of the Pleurotus ostreatus POXC laccase isoenzyme has been tested against selected single textile acid dyes (two anthraquinonic and two azo dyes), as well as towards a solution mimicking a real acid dye waste-water for wool. The catalytic reaction of POXC has been investigated both in the presence and in the absence of the synthetic mediator violuric acid (VIO) (–NOH type of mediator). In all the cases tested, the presence of the mediator enhanced the reaction rate and the percentage of decolorization, apart from one of the dyes (Acid Blue 62), which is itself a good substrate for the laccase-catalyzed oxidation. Electron paramagnetic resonance (EPR) experiments, after the addition of an excess of VIO to the solution of laccase, showed the presence of a strong and stable radical signal that was assigned to a neutral radical form of VIO.