Bleaching Step Research Articles

Optimization of bleaching process for cellulose extraction from apple and kale pomace and evaluation of their potentials as film forming materials

Celluloses from apple and kale pomaces were extracted through sequentially chemical treatments, characterized, and evaluated for the film forming property. Since bleaching step is critical to cellulose quality, bleaching conditions including concentration of bleaching agent (NaClO) (0.5–3 %), temperature (60−80 °C) and time (1−2 h) were optimized. NaClO concentration and temperature exhibited significant impact on the quality of celluloses. Excessive bleaching conditions caused severe oxidation of celluloses and significantly reduced their dimension. The optimum bleaching conditions for apple pomace were identified as 1–1.5 % NaClO at 80 °C for 1 h, resulting in cellulose yield of 7.9 %, water retention value of 2.96, and whiteness index of 72.36. Morphological analysis of optimum apple pomace-celluloses revealed their long-shaped structure with 500−750 μm in length and 20−25 μm in width. The prepared cellulose films had high transparency and good mechanical strength. This study provided new insight in converting fruit processing byproducts into high quality celluloses.

Single Molecule Fluorescence Imaging Reveals the Stoichiometry of BKγ1 Subunit in Living HEK293 Cell Expression System

Large conductance Ca2+-activated K+ (BKCa) channels are ubiquitously expressed in plasma membrane of both excitable and non-excitable cells and possess significant physiological functions. A tetrameric complex of α subunit (BKα) forms a functional pore of BKCa channel. The properties of BKCa channel, such as voltage-dependence, Ca2+ sensitivity and pharmacological responses, are extensively modulated by co-expressing accessory β subunits (BKβ), which can associate with BKα in one to one manner. Although the functional significance of newly identified γ subunits (BKγ) has been revealed, the stoichiometry between BKα and BKγ1 remains unclear. In the present study, we utilized a single molecule fluorescence imaging with a total internal reflection fluorescence (TIRF) microscope to directly count the number of green fluorescent protein (GFP)-tagged BKγ1 (BKγ1-GFP) within a single BKCa channel complex in HEK293 cell expression system. BKγ1-GFP significantly enhanced the BK channel activity even when the intracellular Ca2+ concentration was kept lower, i.e., 10 nM, than the physiological resting level. BKγ1-GFP stably formed molecular complexes with BKα-mCherry in the plasma membrane. Counting of GFP bleaching steps revealed that a BKCa channel can contain up to four BKγ1 per channel at the maximum. These results suggest that BKγ1 forms a BKCa channel complex with BKα in a 1 : 1 stoichiometry in a human cell line.

Influence of refining processes on the bioactive composition, in vitro antioxidant capacity, and their correlation of perilla seed oil

The effect of chemical refining process on the bioactive composition, in vitro antioxidant capacity, and their correlation of perilla seed oil (PSO) were investigated. In this paper, seven samples corresponding to each step of the refining process (degumming, neutralization, bleaching, deodorization, winterization, crude, and refined oils) were studied. The results showed that phenolic compounds and tocopherols were removed from PSO to a degree of 19.4% and 5.4%, respectively. In addition, the carotenoid content of PSO decreased during the refining process. The main carotenoid of PSO was found to be lutein, and the compound was lost completely during the bleaching step of the refining process. In this paper, we analyzed the variation of carotenoid content in PSO during the refining process for the first time. Neutralization affected the contents of phytosterols the most, followed by the effects of degumming and bleaching. The demonstrated results of Pearson product-moment correlation indicated that total tocopherols were significantly correlated with the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and oxygen radical absorption capacity (ORAC) values, whereas carotenoids were significantly correlated with the DPPH value. However, phenolic compounds and phytosterols have no significant difference with DPPH, 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, ORAC, and ferric reducing antioxidant power values. The collected information can be applied to seeking out optimum factors needed to suffice the fundamental requirements for PSO production and minimize micronutrient losses to enhance its market value. PRACTICAL APPLICATION: The present study aimed to determine influence of chemical refining in the bioactive composition of perilla seed oil (PSO) as well as its antioxidant capacity in vitro. Moreover, we also intend to find the correlation between them. Results indicated that this study supplies a good reference for the industrial parameters of the refining process to minimize micronutrient losses and further obtain high-quality PSO products for consumers.

Physicochemical Characteristics of Fungal Xylanases and their Potential for Biobleaching of Kraft and Non-wood Pulps

Xylanases are enzymes with a wide variety of biotechnological applications, such as in the bioconversion of lignocellulosic materials, improvement of feed digestibility, and bleaching kraft pulps to increase pulp brightness. Many studies have been conducted and published over the years on cellulose pulp bleaching due to the need to search for more sustainable tools and thus reduce environmental pollution. Thus, in this review, we focus on analyzing the biochemical properties of xylanases produced by mesophilic and thermophilic fungi that have been used in the bleaching processes of kraft and non-wood pulps. Eucalyptus kraft pulp is still one of the most used raw materials in the production of pulp and paper, while straw and bagasse are alternative sources of non-wood pulps. Thermophilic fungal xylanases show optimum enzymatic activity at high temperatures and a shorter treatment period when compared to mesophilic xylanases in the bleaching step. However, mesophilic fungal xylanases exhibit a longer period of enzymatic treatment but achieve a satisfactory brightness and kappa number. Hence, these approaches will contribute to future applications of these xylanolytic enzymes in pulp and paper industries.

Survey on chemical, physical, and thermal prediction behaviors for sequential chemical treatments used to obtain cellulose from Imperata Brasiliensis

The effects of chemical treatment sequences on the chemical, physical, and mainly the thermal properties of Imperata Brasiliensis grass in the process used to obtain cellulose fibers were analyzed. The thermal properties were extensively investigated by a thermogravimetric analysis, and a thermal behavior prediction was carried out using kinetic parameters and simulation. Thermal simulations using statistical tools enable thermal predictions for any material under different conditions. However, they are currently not widely reported in the literature for untreated and treated natural fibers. We used an alkaline treatment and alkaline treatment followed by one, two, or three bleaching steps with hydrogen peroxide (H2O2) (24% v/v). After each chemical treatment, changes in chemical composition due to the removal of amorphous constituents were observed and confirmed by the analysis of properties such as coloration, density, porosity, crystallinity, and thermal decomposition. The alkaline treatment followed by one step of bleaching was the most effective and viable chemical treatment sequence to obtain cellulose. The changes in coloration from dark brown to light yellow were accompanied by increases in real density (65%), crystallinity (69%), and thermal stability (27.4%) upon one step of bleaching. In general, the subsequent bleaching steps provided similar values. The predicted thermal degradation profiles were compared with experimental data in order to validate the proposed degradation mechanisms and models. The obtained kinetic parameters adequately described the mass loss histories of the studied natural fibers, even when extremely simplified kinetic schemes were used. The degradation mechanisms consisted of diffusion followed by autocatalytic reactions for all studied fibers.

Modification of AgNOR staining to reveal the nucleolus in thick sections specified for stereological and pathological assessments of brain tissue

BackgroundVarious stains have been devised to reveal degenerative or reactive cell phenotypes, or the disintegrative and/or neuropathic lesions associated with Alzheimer's, Parkinson's, and Pick's diseases, Down's syndrome, or chemical toxicity. Utilization of silver staining has allowed researchers to elucidate neural pathways promoting a greater understanding of the functional connections between brain regions. All of these methods employing silver can be characterized as ‘directed staining technologies’. New methodsThe argyrophilic proteins (AgNOR) staining protocol was modified to stain nucleoli in thick sections prepared for stereological evaluation of brain tissue. Nucleoli appeared as black dots against a pale amber background. Tissue sections were counterstained with Toluidine Blue, or reduced-strength Tyrosine Hydroxylase immunohistochemistry to facilitate visualization of basic cellular morphology and regional nucleus identification. Here, we present a modified method for nucleolar staining in free-floating thick sections of brain embedded in a gelatin matrix. The modifications in our procedure include incubation in HCl to denature (‘unravel’) the DNA, a bleaching step to reduce non-specific background silver staining, and counterstaining with Toluidine Blue or reduced-strength tyrosine hydroxylase immunohistochemistry. Comparison with old methodsPrior to the development of immunohistochemistry, silver staining was used primarily to identify pathological profiles and trace axon pathways; however, in many cases, a combination of silver staining and immunohistochemistry are required to fully visualize pathomorphology. The mechanism of these stains requires the binding of silver ions to cellular components and the subsequent reduction of the ions to metallic silver. Dilutions of TH primary antibody were evaluated to maximize identification of neurons and the nucleolus amongst the soma and processes present in the thick section. The use of stereology as a tool to estimate cell number has become increasingly prevalent in neuroscience experiments. As requirements for the preparation of experimental tissue have been refined, researchers have begun to use thicker sections, between 40 to 80 microns, to increase the number of optical planes available for analysis. These thick sections require modified staining protocols to assure complete penetration of stains throughout the tissue section. ConclusionsThis method is particularly useful in nucleolar identification for Stereology, and automated counting methods. Use of the nucleolus avoids some of the problems associated with use of the nucleus. The nucleolus is smaller than the nucleus and is less susceptible to transection during sectioning. It has a higher density than the nucleus and is easier to visualize. It is generally darker staining than the immunohistochemical reaction product that provides the identification marker for the cells to be counted. Examples of the method in several brain sections of the rat are shown, though the method has been also proven in other mammalian models.

Xylanase enzyme production from Bacillus australimaris P5 for prebleaching of bamboo (Bambusa tulda) pulp

Production of Xylanase from a potential bacterial strain Bacillus australimaris P5 and its characterization have been studied. The different parameters of enzyme production were optimized and a xylanase titre of 104 U/ml was obtained. The extracted xylanase was applied on unbleached bamboo pulp @ 10 U/g, maintaining temp at 60 °C, pH at 8, time 2 h and the pulp consistency at 10% which was found suitable for pre bleaching of bamboo unbleached pulp. Xylanase prebleaching decreased the pulp kappa no by 29.5% and improved ISO brightness by 11.4%. Pre-treatment also improved the physical properties of pulps and reduced the requirement of bleaching chemicals in subsequent bleaching steps. Variations in pulp cellulose crystallinity were measured by X-ray diffraction analysis. Scanning Electron Micrographs of cellulose fibre revealed the changes in the morphology and surface property in enzyme treated pulp fibers.

Semi–automated standardisation of melanin bleaching procedures of heavily pigmented melanocytic lesions for immunohistochemical analysis on an automated platform

ABSTRACTBackground: The diagnosis of heavily pigmented melanocytic lesions is problematic. This is often compounded by lack of visibility of nuclear detail of tumour cells due to physical masking by melanin pigment. Similarly, there can be colour merging of chromogenic final reaction products with melanin, making an evidence of antigenic localisation problematic. There are a number of melanin bleaching techniques available for immunohistochemical assessments.Material and methods: All methods to date have involved the bleaching of melanin as a manually performed primary step before loading subsequently bleached slides onto automated immunohistochemical platforms. Here we define a semi-automated bleaching procedure that allows full integration on one of the most widely employed automated IHC staining platforms (Roche Ventana BenchMark Ultra). The bleaching protocol was defined on the BenchMark Ultra and involved the assessment of 24 histological cases of heavily pigmented malignant melanoma lesions (13 cutaneous and 11 metastatic) routinely fixed processed and paraffin wax embedded.Results: Completion of the bleaching was assessed on H&E preparations performed following the semi-automated bleaching step and employing the Roche Ventana BenchMark Ultra machine for 60 min at 42°C. Complete immunohistochemical staining was achieved on the automated platform within 5–6 h including the bleaching step. Results were consistent across all tissue evaluated.Discussion: This data provides evidence that the hydrogen peroxide bleaching procedure can be adapted for integration on one of the most widely employed automated IHC staining platforms and as a result, improve the efficiency and reproducibility of the technique.

Isotherms, kinetics, and thermodynamic studies for adsorption of pigments and oxidation products in oil bleaching from catfish waste

The aim of this work was to study the bleaching of oil extracted from the heads of the catfish by thermomechanical process through equilibrium, kinetics, and thermodynamics adsorption studies. The condition for the bleaching step was with 1% (w/w) adsorbent composed of 95% activated earth and 5% activated carbon (w/w). The pseudo-first order and pseudo-second order models were the most appropriate to represent the adsorption kinetics. The temperature of 80 °C increased the adsorption capacity of the two adsorbates, and the activation energies values were of 47.47 and 44.82 kJ mol−1, respectively, for the adsorption of carotenoids and peroxides. The Langmuir model was the most appropriate to describe the bleaching equilibrium curves. The thermodynamic parameters revealed that the processes were endothermic, favorable, and spontaneous and the interaction between adsorbent and adsorbate was physical.

Automated Stoichiometry Analysis of Single-Molecule Fluorescence Imaging Traces via Deep Learning.

The stoichiometry of protein complexes is precisely regulated in cells and is fundamental to protein function. Singe-molecule fluorescence imaging based photobleaching event counting is a new approach for protein stoichiometry determination under physiological conditions. Due to the interference of the high noise level and photoblinking events, accurately extracting real bleaching steps from single-molecule fluorescence traces is still a challenging task. Here, we develop a novel method of using convolutional and long-short-term memory deep learning neural network (CLDNN) for photobleaching event counting. We design the convolutional layersto accurately extract features of steplike photobleaching drops and long-short-term memory (LSTM) recurrent layers to distinguish between photobleaching and photoblinking events. Compared with traditional algorithms, CLDNN shows higher accuracy with at least 2 orders of magnitude improvement of efficiency, and it does not require user-specified parameters. We have verified our CLDNN method using experimental data from imaging of single dye-labeled molecules in vitro and epidermal growth factor receptors (EGFR) on cells. Our CLDNN method is expected to provide a new strategy to stoichiometry study and time series analysis in chemistry.

EyeCi: Optical clearing and imaging of immunolabeled mouse eyes using light-sheet fluorescence microscopy

Immunofluorescent imaging is an indispensable technique to study morphology and molecular aspects in tissues. Classical approaches make it necessary to cut physical sections of tissue samples to overcome the limited penetration depth of light, restricting the available information to two dimensions. Recent advances in tissue-clearing techniques enable imaging of fluorescently labeled organs and entire organisms on a cellular level in three dimensions without the need of sectioning. Volume imaging of immunolabeled and cleared tissues started a new era of systems biology, because these techniques provide information on connectivity and circuits, especially in structures with projections in three dimensions such as vascular or nervous systems. The variety of published clearing protocols allows the imaging of every organ with a single exception: the eye. Whole-eye clearing approaches were unsuccessful so far due to the strong pigmentation of the retinal pigment epithelium. Here, we present a new protocol that combines a highly effective melanin bleaching step with solvent-based clearing, termed EyeCi. The protocol is compatible with immunolabeling as demonstrated by the visualization of ocular and retinal vasculature in the intact mouse eye by means of light-sheet fluorescence microscopy. This novel protocol is rapid (1 week) and inexpensive, hence allowing high-throughput, high resolution analysis of vascular architecture of healthy and diseased eyes, in its native, three-dimensional organization within intact eyeballs. Volume imaging of whole cleared eyeballs further enables three-dimensional surface reconstruction and automated quantification of choroidal and retinal vasculature extending ocular imaging to a global level. Thus, EyeCi represents an extension to state-of-the-art light microscopy techniques and is potentially suitable for the investigation of vascular leakage or neovascularization processes.

Effect of lights with various wavelengths on bleaching by 30% hydrogen peroxide.

The objective of this study was to evaluate the bleaching effect of light sources with various wavelengths using 30% hydrogen peroxide (HP) in vitro. The hematoporphyrin-stained paper was bleached with HP and irradiated for 10min using LED light sources with 265, 310, 365, 405, or 450nm respectively. In control group, HP was applied for 10min without light irradiation. The bleaching procedure was repeated two times. The L*a*b* values of the samples before bleaching and after each bleaching step were measured using a colorimeter. Color changes of specimens were then calculated and statistically analyzed. There was an interaction between light sources and time of irradiation in the color change (p < 0.05). Time and light sources significantly affected ΔE and ΔL (p < 0.05). The light source of 256nm showed the highest bleaching effect over time followed by that of 310nm, which were statistically different from other groups (p < 0.001). The 365nm, 450nm groups, and control group showed low bleaching effect visually with no significant differences in ΔE and ΔL (p > 0.05). It was concluded that the wavelengths of the light sources affected the bleaching by HP. The 310-nm light can be a potential source for bleaching.

High-Resolution Peat Core Chronology Covering the Last 12 KYR Applying an Improved Peat Bog Sampling

ABSTRACTThis work focuses on building a high-resolution age-depth model for quantitative palaeoclimate study from the Mohos peat bog, East Carpathian mountains. The investigated core presents a continuous peat profile for the last 12 kyr. The chronology was based on 36 accelerator mass spectrometry radiocarbon (AMS14C) analyses of the separatedSphagnumsamples from different depths of the profile. DrySphagnumsamples for AMS dating were prepared using the classic acid-base-acid (ABA) method followed with an oxidative bleaching step to get clean cellulose.Sphagnumcellulose samples were measured by AMS using the EnvironMICADAS at the ICER (Debrecen, Hungary). A high-resolution chronology was obtained with the use of Bayesian age-depth modeling. Peat accumulation rate has been calculated and the sections with variable accumulation rate values were observed along the profile.

Extractive Profiles in the Production of Sulfite Dissolving Pulp from Eucalyptus Globulus WOOD

The profile of major families of extractives soluble in acetone and dichloromethane during the production of acid sulfite dissolving pulp from Eucalyptus globulus wood was assessed. Nearly 85% of total extractives were removed from wood during pulping and nearly 11% in the course of E-O-P pulp bleaching and secondary pulp screening. Unlike extractives of polyphenolic origin that were almost completely removed after the alkaline extraction stage (E), fatty acids were the main retained component in fully bleached pulp followed by sterols and fatty alcohols. Throughout the bleaching steps, the profiles of extractives were not necessarily decreasing and depended on their reactions with bleaching reagents and the presence of auxiliary chemicals (e.g. antifoams). In this context, the content of fatty acids and fatty alcohols was mostly vulnerable. It has been suggested that Fock reactivity of dissolving pulps is unaffected by extractives at concentrations up to 0.3%.

Effect of refining on bioactive composition and oxidative stability of hazelnut oil

In this study, the effect of refining process on the content of phytochemicals, antioxidant capacity and oxidative stability of hazelnut oil was investigated. The oil samples were taken at the consecutive steps of hazelnut refining process and analyzed for some compositional properties along with the antioxidant capacity and oxidative stability. The results have shown that, carotenoid content of the hazelnut oil was decreased during the refining process. The main carotenoids of hazelnut oil were found to be lutein and zeaxanthin and these compounds were lost completely during bleaching step of the refining. On the other hand, phenolic compounds and tocopherols were also partly removed from hazelnut oil to a degree. Loses in antioxidant compounds caused a clear decrease in antioxidant capacity measured in either the oils or polar extract of oils. Oxidative stability of the oil samples was measured by Rancimat method and it was found that neutralization caused an increase in oxidative stability compared to the crude oil. However, deodorization step caused a slight decrease in oxidative stability probably as a result of partial removal of tocopherols at this stage.

Modeling of the soybean oil bleaching and optimization of its conditions in the refining process for environmental interest

Abstract In this work, we propose mathematical models describing the soybean oil bleaching process as a function of its parameters (temperature: 80 – 120 °C, clay dosage: 0.25 – 2 %, contact time: 10 – 30 min). The crude soybean oil visible spectrum shows three values of maximum wavelength (λmax). A value at 426 nm corresponding to the chlorophyll-a, the values at 451 and at 479 nm were assigned to β-carotene pigment. The models were developed using multiple linear regression analysis (MLRA) and were performed with Matlab programming language. The input variables are the temperature (X1), the clay dosage (X2) and the contact time (X3). The output parameter is the bleaching capacity (Y in % uptake). Statistical analysis methods were used to analyze and to confirm the reliability of the selected models. The optimal bleaching conditions for the soybean oil were: temperature 100 °C; clay dosage 2 % w/w and contact time 30 min. The highest bleaching capacity was found to be 81.04 % at 426 nm, 90.60 % at 451 nm and 93.66 % at 479 nm. The developed models allowed predicting the bleaching capacity representing the removal of the β-carotene and chlorophyll-a pigments present in the crude soybean oil at each λmax. Also they allowed a better control of the most influencing parameters on the bleaching step and contribute to the optimization of the spent bleaching clay rejects by optimizing the amount of bleaching clay used in the refining process; consequently, to reduce risks of pollution.

Properties of Cellulose Extract from Different Types of Oil Palm Biomass

This study focuses on the characteristics of cellulose extracts from different oil palm biomass namely oil palm mesocarp fiber (OPMF), oil palm empty fruit bunch (OPEFB) and oil palm frond (OPF). Cellulose was obtained from these biomass through soda pulping process followed by a totally chlorine free (TCF) bleaching step using peracetic acid solution. It was found that the cellulose extract for OPMF, OPEFB and OPF had 88.8%, 93.0% and 94.6% purity. Further analyses on the properties of cellulose in terms of morphology, thermal stability and crystallinity were conducted. The OPF cellulose obtained after pretreatment exhibited the highest crystallinity at 84.5%, followed by OPEFB (82.4%) and OPMF (69.2%). This directly affected the thermal stability of the celluloses, in which OPF cellulose was more thermally stable compared to celluloses from OPEFB and OPMF, as being recorded by a thermogravimetry analyzer (TGA). Results from this study provide new insight not only for fundamental understanding, but also to forecast the potential applications of cellulose extracts from different type of oil palm biomass, based on the performance of the celluloses reported herein.

Ethylcellulose oleogels with extra virgin olive oil: the role of oil minor components on microstructure and mechanical strength

The structuring of Extra Virgin Olive Oil with ethylcellulose and the role of oil minor compounds on oleogel structural and mechanical properties were investigated. To this aim a refining process, consisting of degumming, neutralization and bleaching steps, was applied to the oils to progressively remove specific minor components. At each step, the oils were characterized by free fatty acids and polyphenol contents, primary and secondary oxidation products and polarity of the solvent; the purified oils were then used to produce ethylcellulose-based oleogels. Large deformation tests such as Back Extrusion and Two Plates Compression Analysis were performed to investigate the mechanical properties of the oleogels, while the microstructure was studied by Atomic Force Microscopy. Results showed that the purification steps affected the chemical composition of the oils and their polarity which, in turn, influenced oleogel properties. From a microstructural perspective, a change in the size, diameter and shape of the pores in the gels produced with the purified oils was observed. Pore roundness and circularity decreased throughout the purification, with a progressive loss in roundness and circularity and a predominance of elongated and bean-shaped pores as minor compounds were selectively removed from the matrix. A decreasing trend in gel hardness was observed upon oil refining showing that minor compounds significantly affected also the mechanical properties of the oleogels. The polarity of the solvent and the presence of minor components were confirmed to be important parameters to determine the relation between ethylcellulose network characteristics and oleogel mechanical strength. From a multiple partial least regression MPLSR, it resulted that pores diameter, roundness and circularity were positively affected by polar and amphiphilic compounds like polyphenols while gel hardness was positively influenced by free fatty acids and total polar compounds.

Effects of cultivation, washing, and bleaching conditions on bacterial cellulose fabric production

This study aims to compare different conditions in the three-step (cultivation, washing, and bleaching) production of white bacterial cellulose (BC) fabric to introduce it as a new type of fabric in the textile industry. The BC fabric was evaluated on the basis of its surface morphology and chemical structure. The “production BC” after the cultivation step was cultured using glucose as the carbon source in the Hestrin–Schramm (HS) medium. It was produced with the highest production yield (33.2 ± 6.85%), the highest thickness (0.35 ± 0.09 mm), and the flattest surface (211 nm). The bacteria remaining on “washed BC” after the washing step were washed out using 3% NaOH solution, and the nanoscale network structure maintained its integrity after washing. The white BC fabric after the bleaching step was bleached using 5% H2O2 solution. The white BC fabric with the highest white index (73.15 ± 1.09%) without a natural yellowish-brown color was produced. In the Fourier transform infrared spectroscopy (FTIR) spectra of the white BC fabric, the peaks of proteins and amino acids derived from the bacteria disappeared, while the cellulose I crystal structure was maintained. Also, X-ray diffraction analysis showed that the crystallinity of the white BC fabric increased compared to that of the control sample, and the highest crystallinity of 80.6% was obtained.

Outcome of Refining on the Physicochemical Properties of Cottonseed Oil

The influence of refining processes on the physicochemical properties including fatty acid composition of cottonseed oil (CSO) was studied. Physicochemical properties were determined by standard AOCS and IUPAC methods. The obtained results of physical parameters showed that neutralization, bleaching and deodorization processes on crude CSO significantly reduced the moisture content, color, freezing point and smoke point, while slightly decrease in refractive index was observed. Similarly, in the case of chemical properties free fatty acids, saponification value and peroxide value were reduced from 1.7 to 0.15%, 175 to 173 mg KOH/g oil and 3.4 to 1.2 mEq O2/Kg oil, respectively. Refining processes did not showed significant effect on the fatty acid composition and iodine value. As, soap contents generated in the chemical neutralization step, therefore soap content were decreased from 61.0 to 15.5 ppm in bleaching and deodorization steps. Moreover, this work suggests that overall deodorization process has greater impact on physicochemical properties to improve the quality and stability of cottonseed oil.