Search results

The purpose of this study was to assess the repercussions of eucalyptus bark and tea leaf extract as natural dyes and antibacterial agents for jute–cotton union fabric.

The dye was collected from the eucalyptus tree’s bark and tea leaves by the aqueous extraction method. The fabric was dyed with potassium alum mordant, using pre-mordanting, post-mordanting and meta-mordanting methods. Examine the color performance analyzed the K/S, L*, a*, b*; fastness to washing using standard test method ISO 105 C06 A2S, rubbing fastness was performed by Crock meter using AATCC 115. The dyed fabrics were characterized by Fourier transform infrared radiation for the existence of various functional groups. Also, antimicrobial activity testing was done by the agar diffusion method (AATCC method SN 195 920) where Escherichia coli and Staphylococcus aureus were used.

The extracted dye tea leaves meta-mordant dyed samples were determined to have the strongest relative color. Fabrics pre-mordanted and post-mordanted with extracted eucalyptus and extracted tea dye produced the same outcome, which was excellent for wash fastness to staining and very good for wash fastness to fading. For both eucalyptus bark and tea, rubbing fastness on the pre-mordanted fabric produced very positive results. In mordanted colored fabric, significant antibacterial activity was discovered against S. aureus and E. coli.

This study demonstrates that the eucalyptus bark and tea leaves extract encompasses a solid antimicrobial action with amazing coloring execution for jute–cotton union fabric.

The purpose of this paper is to carry out phytochemical investigations of different extracts of Eucalyptus globulus bark such as aqueous, methanolic and supercritical carbon dioxide fluid extract (SCFE) with ethyl acetate as entrainer. Three fractions (Eu 8, 9 and 10) containing steroidal δ‐lactone were isolated from SCF extract and the structure of Eu‐10 was earlier determined on the basis of NMR, HPLC‐MS, X‐Ray crystallography.

Column chromatography led to the isolation of flavonoids, tannins, steroids, etc. in different solvent systems. Isolated steroidal lactone (Eu‐8,9&10) of Withanolide series were tested for the presence of total phenolic content, total flavonoid content and the results were expressed as gGAE/100 g (TPC), and gQE/100 g (TFC), respectively. The antioxidant capacity was evaluated based on their ability to scavenge free radicals generated from ABTS, DPPH, FRAP and H₂O₂ by spectrophotometric method.

The result of the present study showed that different extracts of E. globulus bark and the isolated fractions, exhibited different antioxidant activity. This was due to the fact that they contained different amounts of flavonoid and phenolic compounds as per their ability to solubilize these compounds; the high scavenging property of E. globulus may be attributed to hydroxyl groups existing in the phenolic compounds. All the samples exhibited different extent of antioxidant activity (AOA) and showed higher potency when compared with BHT in scavenging action of DPPH free radical. Comparative data analysis showed SCF extract to be better than methanolic and aqueous extracts, both in terms of yield and AOA, while Eu‐10 was the best amongst purified fractions.

The present research has serious implications on identification of natural antioxidants from E. globulus. Natural antioxidants with better structure‐activity relationship are under investigation. Isolation of withanolide from Eucalyptus bark has opened newer horizon for its use.

Collection of Eucalyptus bark from the forest (a forest waste) by women folk can be a source of revenue generation and thus has social implication as well. It is an important agro product.

The steroidal lactone (Eu‐10) showed highest radical scavenging effect even at IC50, thus the isolated lactone proved to be the best potential scavenger of free radicals amongst all crude extracts and the isolated fractions.

Commercial natural dyes are quite costly as manufacturers are to follow multi-step extraction and purification procedures for standardisation purposes. Upon cost comparison, they lose in the market to synthetic dyes. However, in the handicraft sector, reproducibility may be of lesser importance against cost. In the present study, a domestic method of dyeing silk with the aqueous extract of raw plant/tree components (flower, leave, bark and root) by using a natural mordant and alum will be described. Good dyebath exhaustion and washing and light fastness are observed for some of the natural colouring matters.

The efficiency of UV radiation on boiled aqueous and alkaline extracts of Eucalyptus bark powder has been determined. Irradiated and un-irradiated cotton fabrics were used to study the dyeing parameters such as material-liquor ratio, dyeing time and dyeing pH. Pre- and postmordanting were carried out by using copper and iron mordants. The data colour report was obtained for evaluation of un-irradiated and irradiated dyed cotton using a Spectra Flash (SF- 650) in the CIE Lab system. It was found that UV irradiation has the potential to improve dyeing and fastness properties, such as washing, light and rubbing, of cotton dyed with Eucalyptus bark powder.

This paper aims to investigate the potential application of Balanites aegyptiaca bark powder (BABP) for removing a basic textile dye, methylene blue (MB), from aqueous solutions.

The biosorbent (BABP) was characterized using Fourier transform infrared spectroscopy (FTIR) and point of zero charge (pH_PZC). Batch mode was selected to study the biosorption of MB onto BABP surface at different experimental conditions (shaking speed, contact time, initial solution pH, ionic strength, solution temperature, biosorbent dosage and initial dye concentration). Besides, the reusability of BABP for MB biosorption was also examined.

The biosorption results revealed that approximately 96% of MB was removed successfully at the optimized operational conditions. Pseudo-second-order and Langmuir models, respectively, better described the adsorption kinetics and isotherms. The monolayer biosorption capacity (q_max) for MB was about 97.09 mg/g. According to thermodynamics findings, the MB biosorption onto BABP is an exothermic and spontaneous process. The results demonstrate that BABP can be considered as potential eco-friendly, readily available and low-cost biosorbent for hazardous textile dyes removal from water bodies and also provides a promising method for minimization of agricultural solid wastes (e.g. plant barks).

The utilization of Balanites aegyptiaca bark powder (BABP), solid waste material, as low-cost and eco-friendly biosorbent for the removal of hazardous basic textile dye (methylene blue) from the aquatic environment.

Everyone is extremely concerned about environmental protection and health safety due to the rise in living standards. Plant-derived natural dyes have garnered much industrial attention in food, pharmaceutical, textile, cosmetics, etc. owing to their health and environmental benefits. The present study aims to focus on the elimination of the use of synthetic dyes and provides brief information about natural dyes, their sources, extraction procedures with characterization and various advantages and disadvantages.

In producing natural colors, extraction and purification are essential steps. Various conventional methods used till date have a low yield, as these consume a lot of solvent volume, time, labor and energy or may destroy the coloring behavior of the actual molecules. The establishment of proper characterization and certification protocols for natural dyes would improve the yielding of natural dyes and benefit both producers and users.

However, scientists have found modern extraction methods to obtain maximum color yield. They are also modifying the fabric surface to appraise its uptake behavior of color. Various extraction techniques such as solvent, aqueous, enzymatic and fermentation and extraction with microwave or ultrasonic energy, supercritical fluid extraction and alkaline or acid extraction are currently available for these natural dyes and are summarized in the present review article.

If natural dye availability can be increased by the different extraction measures and the cost of purified dyes can be brought down with a proper certification mechanism, there is a wide scope for the adoption of these dyes by small-scale dyeing units.

The purpose of this paper is to evaluate the effect of different amounts of sodium hydroxide (NaOH) introduced during the resin synthesis on the properties of bark‐phenol‐formaldehyde (BPF) adhesives aims at achieving a balance between storage life and other properties of BPF adhesives.

Based on the best synthetic technologies for the production of BPF adhesives obtained in a previous study, a new synthetic technology is developed for the production of BPF adhesives that involve a three‐step addition of NaOH using different amounts of NaOH in the third charge. Gel permeation chromatography is used to evaluate properties of the phenol‐formaldehyde (PF) and BPF adhesives.

The amount of NaOH in the third charge has an important influence on many BPF adhesive properties. The paper determines that the synthetic technology involving three‐step NaOH additions with only water introduced in the third charge of NaOH produces a BPF adhesive with the longest storage life and best bonding strength.

BPF adhesives are very complex systems with many unknown variables.

The improved storage life of the BPF adhesive prepared with the new synthetic technology is comparable to that of a commercial PF adhesive, which indicates that this new technology shows greater potential for commercial applications.

A new synthetic technology is developed to produce a BPF adhesive that is more comparable to commercial PF adhesives than other BPF adhesives in terms of storage life and other resin properties.

This study aims to explore the possibility of using magnetic biochar composite (MBCC) derived from Heglig tree bark (HTB) powder (agricultural solid waste) and cobalt ferrite (CoFe₂O₄, CFO) for oil spill removal from seawater surface.

One-pot co-precipitation route was used to synthesize MBCC. The prepared materials were characterized by X-ray diffraction, scanning electron microscopy-energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy. The densities of the prepared materials were also estimated. Crude, diesel engine and gasoline engine oils were used as seawater pollutant models. The gravimetric oil removal (GOR) method was used for removing oil spills from seawater using MBCC as a sorbent material.

The obtained results revealed that the prepared materials (CFO and MBCC) were able to remove the crude oil and its derivatives from the seawater surface. Besides, when the absorbent amount was 0.01 g, the highest GOR values for crude oil (31.96 ± 1.02 g/g) and diesel engine oil (14.83 ± 0.83 g/g) were obtained using MBCC as an absorbent. For gasoline engine oil, the highest GOR (27.84 ± 0.46 g/g) was attained when CFO was used as an absorbent.

Oil spill removal using MBCC derived from cobalt ferrite and HTB. Using tree bark as biomass (eco-friendly, readily available and low-cost) for magnetic biochar preparation also is a promising method for minimizing agricultural solid wastes (e.g. HTB) and obtaining value-added-products.

This paper aims to investigate the tensile behavior of epoxy and polyester matrix composites reinforced with continuous and aligned aloe vera fibers.

Composites with different volume fractions (30, 40 and 50 Vol. %) were fabricated by laying the fibers in a steel mould and pouring liquid resin, either DEGEBA/TETA epoxy or methyl-ethyl ketone hardened orthophthalic polyester, under pressure of 3 MPa. The specimens were cured for 24 h at room temperature and then tested in a universal Instron testing machine, model 5582, at 298 K (25°C).

The fracture surface was analyzed by scanning electron microscopy (SEM) under an acceleration voltage of 15 kV. SEM fractography revealed a poor adhesion between both the epoxy and polyester matrices with the aloe vera fiber. The results showed that in both cases the introduction of aloe vera fibers had a minor effect on the matrix reinforcement.

Investigation and comparison of tensile behavior of epoxy and polyester matrix composites reinforced with continuous and aligned aloe vera fibers have not been attempted so far.

This paper aims to focus on the aqueous extraction of natural dye from haematoxylum campechianum L. bark for finishing the bio-mordant cotton fabrics producing value-added, environment-friendly textile products, for biomedical applications.

The study focuses on the creation of eco-friendly bio-mordant cotton fabric using gallic acid and gelatin, Al³⁺ and Fe²⁺ salts and metal mordant. The optimal pH for extraction, structural characterization and phytochemical analysis of the extracted dye were estimated using UV-visible spectrophotometer, FTIR and qualitative analysis. Variations in electrolyte concentration and pH medium were also considered. The study also examines build-up properties, colorimetric values and fastness characteristics of the colored fabrics.

All the dyed fabrics exhibit very good to excellent in terms of antimicrobial resistance against S. aureus and C. allbicans.

Pre-mordant cotton fabrics with Fe²⁺ and a combination of metal and bio-mordant show higher antibacterial resistance against P. aerugionsa. Further, bio-mordant and a combination of both mordant exhibit excellent UV protection and antioxidant activity performance compared to that of undyed fabrics.

This work opens up a huge potential for producing healthy bioactive-colored fabrics used in medical textiles and other usages.