Seed Coat Fragments Research Articles

Effect of seed coat fragments on cotton yarn structure: impact of fragment size, attached fibres and position within yarn core

Seed coat fragments are a major source of cotton yarn imperfections. This article discusses the factors influencing the disruption caused by seed coat fragments in ring-spun yarn structure with a focus on three characteristics: the fragment's size, the amount of fibres attached to it and its position relative to the yarn core. The three characteristics were investigated through two experiments involving various types of yarn defects and a range of ring-spun yarn counts. Results presented in this article indicate that the three factors considered have a significant influence on the intensity of the disruption the seed coat fragment causes in the yarn structure, and are determinant of the type of defect that this disruption engenders (short/long defect).

Tracking Seed Coat Fragments in Cotton Ginning

Seed coat fragments (SCF) in lint cause problems in textile mills during spinning and dyeing, so it is important to prevent or remove them during ginning. The objective of this experiment was to quantify SCF as they were formed and removed during ginning so that future studies can focus on preventing SCF formation. Samples of cotton, seed, and trash were collected throughout a gin to analyze SCF, motes, seed meats, and seed. The lint cleaner did not change the number of SCF in lint, but it reduced the weight of SCF by 56% as it removed larger SCF or broke them into smaller SCF. Seed meats in the ginned seed and small seed missing after the gin stand were estimated to be 0.8% and 2.3%, respectively, of all seed ginned, accounting for 32% and 15% of SCF formed in the gin stand, so a significant portion of SCF was attributed to seed damage not revealed by simply observing damaged seed in the seed roll. Damaged seed observed in the seed roll was 7% higher than in seed cotton, and these were thought to be a major source of SCF found in lint. The SCF mass entering the gin stand was 24% of the SCF mass exiting the gin stand, so a small but significant portion of SCF were formed before the gin stand. Seed meats found in the seed cotton cleaner waste were estimated to account for 22% of SCF found entering the gin stand. Seed damage occurred in the field, in seed cotton cleaners, and in the gin stand, so there are opportunities at each of these steps to prevent SCF in lint.

Effect of hydrolytic and oxidative enzymes produced by solid-state fermentation on greige linen fabric

Solid state fermentation (SSF) was applied for production of fungal enzyme preparations from Phanerochaete chrysosporium, Aspergillus oryzae, Aspergillus giganteus and Trichoderma virens using cotton seed-coat fragment waste as a carbon source and enzyme inducer. Lignin-holocellulose matrix of cotton seed coat fragment proved to be effective in inducing production of ligninolytic, cellulolytic and xylanolytic enzymes in solid-state fermentation. The effect of the enzymes produced by SSF on greige linen fabric is discussed and evaluated. In the first experiment the hydrolytic and accompanying oxidative enzymes in the buffer extract of the whole SSF cultures were used for fabric treatment. In the second trial, the enzymes produced in situ (whole SSF material—mixture of fungal biomass, residual substrate and enzymes) were used for the treatment. Weight loss, reducing sugar liberation and removal of colouring materials were measured. The results showed that at equal enzyme charges the intact SSF materials were more efficient than the enzyme extracts. Of the six strains evaluated, Ph. chrysosporium VKM F-1767 was the most effective in removing colouring matters from greige linen fabric.

Cultivar Differences in Gin Stand Energy Utilization

This study included 38 early and 27 medium maturing cultivars planted in Stoneville, Mississippi (2002 and 2003) and Tribbett, Mississippi (2003). About 50% of the cultivars tested in 2002 were repeated in 2003. Variation in gin stand energy consumption was measured as an indicator of differences in fiber-seed bond strength. After subtracting idling energy, the gin stand consumed an average of 20.2 Wh/kg lint with a range of 16.4 to 24.3 Wh/kg lint across cultivars in all tests. Changes in ginning energy were found to correlate with changes in seed linters content, ginning rate, seed percent, and turnout, but ginning energy did not appear to be dependent on these factors. The gin stand energy requirements were lower for cultivars with large seed and low seed linters content. Ginning energy did not change with fiber length, but it increased with short fiber content as more fibers were broken in multiple places. Cultivars that used less energy during ginning tended to have higher HVI fiber strength, so reduced fiber-seed bond strength was not the result of reduced fiber strength. Ginning energy increased with the number of neps, number of seed coat neps, and weight of seed coat fragments, and it decreased with seed cotton cleaner efficiency. This indicated that energy was used to remove tangled fibers and trash. Some properties were found to be closely related to ginning energy, but ginning energy was thought to be independent of these properties. Evidence suggested that cultivar differences in energy consumption at the gin stand were closely related to differences in the fiber-seed bond strength.

Biopreparation of cotton fabric with enzymes produced by solid-state fermentation

Fungal enzyme preparations from Phanerochaete chrysosporium, Aspergillus oryzae, Aspergillus giganteus and Trichoderma virens, produced by solid-state fermentation (SSF) on cotton seed-coat fragment waste as substrate and enzyme inducer were investigated in biopreparation of cotton fabric. Cotton seed-coat fragment is rich in lignin, cellulose and hemicelluloses, therefore enzyme complexes produced by target fungi on such a substrate can be used effectively to degrade impurities in cotton fabrics during biopreparation. Activities of extracellular hydrolytic and ligninolytic enzymes were determined from the SSF extract materials. The potential of the hydrolytic and accompanying oxidative enzymes in the whole SSF cultures was exploited in degradation of seed-coat fragments and other coloring materials of greige cotton fabric. Enzyme assays indicated that many extracellular enzymes have been produced under these conditions including both hydrolytic and oxidative enzymes. A. oryzae NRRL 3485 produced significantly higher amounts of both hydrolytic and oxidative enzymes than other tested fungi. Best results in removal of seed-coat fragments from cotton fabric were obtained by P. chrysosporium NCAIM (=ATCC 34541), P. chrysosporium VKM F-1767 and A. oryzae NRRL 3485 SSF enzyme complexes.

Genetic variation among cotton ( G. hirsutum L.) cultivars for motes, seed-coat fragments and loading force

Seed quality is one of the important objectives in cotton production and breeding. Seed-coat fragments (SCFs) and motes are the main impurities in lint cotton and are major concerns in the textile industry. A 2-year study was conducted to compare 10 cotton ( Gossypium hirsutum L.) cultivars for the number of SCFs, motes, and resistance to loading force (RL). Although cultivars were not significantly different for the number of SCFs in both years, mean values changed among cultivars and between years. Heritability for the number of SCFs was 0.52 indicating almost equal genotypic and environmental effects on phenotype. There was no correlation between the number of SCFs and RL. Cultivars were different for number of motes. Genotypic and environmental effects on the number of motes were 0.71 and 0.29, respectively. No significant correlation was detected between number of SCFs and RL.

Development and Use of an Attenuated Total Reflectance/Fourier Transform Infrared (ATR/FT-IR) Spectral Database To Identify Foreign Matter in Cotton

The presence of foreign matter in cotton seriously affects the cotton grade and thus the price per bale paid by the spinner to the grower, the efficiency of the spinning and ginning operations, and the quality of the final woven product. Rapid identification of the nature of the extraneous matter in cotton at each stage of cleaning and processing is necessary to permit actions to eliminate or reduce its presence and improve efficiency and quality. Although several instruments are being successfully employed for the measurement of contamination in cotton fibers based on particle size/weight, no commercial instrument is capable of accurate qualitative identification of contaminants. To this end, ATR/FT-IR spectra of retrieved foreign matter were collected and subsequently rapidly matched to an authentic spectrum in a spectral database. The database includes contaminants typically classified as "trash", cotton plant parts (hull, shale, seed-coat fragments, bract, cacyx, leaf, bark, sticks, and stems) and grass plant parts (leaf and stem); "foreign objects and materials", synthetic materials (plastic bags, film, rubber, bale wrapping and strapping); organic materials (other fibers, yarns, paper, feathers, and leather); plus entomological and physiological sugars and inorganic materials (sand and rust). The spectral matching resulted in consistently high-score identification of the foreign matter based on chemical composition, irrespective of its particle size. The method is envisioned to be employed with stand-alone rugged infrared instrumentation to provide specific identification of extraneous materials in cotton as opposed to only general classification of the type by particle size or shape.

Degradation of Lignin-Containing Materials by Xylanase in Biopreparation of Cotton

Solubilization of lignin and carbohydrates from the lignin-holocellulose structure of cotton seed-coat fragments was investigated by UV/VIS spectrometry. Xylanase (Pulpzyme HC) pre-treatment partially destroyed the lignocellulosic structure of the seed-coat fragments, producing reducing sugars and soluble lignin in the supernatant. Furthermore, the pre-treatment by enzyme enhanced the delignification in the subsequent alkaline scouring process and increased the lightness of the substrate.

Role of the EDTA Chelating Agent in Bioscouring of Cotton

Our previous work demonstrated that ethylenediamine-tetra-acetic acid (EDTA) markedly enhances the apparent activity of commercial xylanase and pectinase enzymes in cotton bioscouring, accelerating degradation and removal of impurities. In this study, we explore how EDTA can improve the efficiency of the enzyme process in cotton bioscouring. The effects of EDTA on the enzyme action and degradation of seed-coat fragments—the most resistant natural impurities of cotton to be degraded in bioscouring—are investigated. Results show that application of EDTA in different concentrations does not inhibit the main activities of the enzymes investigated. Thus, the pectinase activity of Viscozyme 120L and the xylanase activity of Pulpzyme HC remain almost unchanged. On the other hand, EDTA modifies the substrate structure by removing the calcium ions from the cross bridges that link the macromolecules in pectin to one another or pectin to other polysaccharides. While EDTA pretreatment significantly decreases the efficiency of enzymatic hydrolysis monitored by reducing sugar liberation, simultaneous application of EDTA and enzyme in one treatment bath largely accelerates the degree of hydrolysis, indicating a synergistic effect of enzyme and EDTA.

Chemical Structural Investigation of the Cotton Fiber Base and Associated Seed Coat: Fourier-Transform Infrared Mapping and Histochemistry

Fourier-transform mid-infrared mapping and histochemical staining are used to reveal the location and relative importance of chemical components involved with the base of cotton fibers and their associated seed coat. These two complementary techniques are focused on the nature of the chemical components that hold cotton fibers at their bases to the seed coat and with other portions of seed coat fragments that are often found as part of the trash component of ginned cotton. Infrared results reveal waxes or long-chain alcohols adjacent to the shank of cotton fiber bases in the outer epidermal tissue in all regions of the cotton seed; uronate anions in the outer epidermis and pigment layers surrounding the bases of the fibers and strongly present in the upper palisade layer tissue of all seed regions; compounds containing carbonyl functionality, acids, and bases, at the juncture of the upper palisade and colorless layers; tannin or pretannin-type aromatic structures in the outer pigment layer and interior to the cells in the epidermal layer of all seed coat regions; and lignin-type aromatics in the "colorless" layer of all regions of the seed coat. The infrared results are complemented by staining with Oil Red O for waxes, Ruthenium Red for pectins, acid phloroglucinol for lignins, and vanillin-HCl for tannins. The results provide a better understanding of fiber-seed interactions that are important to the development of methods for improving the separation of cotton fibers from seed coats. In turn, this will help to avoid breaking fibers and pulling out seed coat fragments with the fibers during ginning.

Seed Coat Fragments: The Consequences of Carding and the Impact of Attached Fibers

Seed coat fragments (SCF) are extremely difficult contaminants to remove from cotton fibers because of the fibers attached to them. Literature data suggest that carding is the most effective cleaning step during which a significant proportion of the SCF is eliminated. In the study described here, different detection methods are used to evaluate the ability of carding to clean SCF-Contaminated cottons. Variations in SCF number and size distribution are evaluated. The amount of fibers attached to the SCF is measured by image analysis, and it appears to have a significant effect on the ability of the card to remove SCF.

Effect of Seed Coat Fragments on Cotton Yarn Strength: Dependence on Fiber Quality

Contaminants in cotton fibers cause yam regularity defects that alter their structure. The effect of these alterations on yarn strength is discussed with particular focus on seed coat fragments (SCF), one of the primary cotton contaminants from the fiber to the finished product. This paper presents the results of an experimental study showing that, in certain cases, the presence of SCF has a significant effect on yarn strength. This effect is closely correlated with fiber quality, and a discussion of this interaction is presented on the basis of different statistical methods.

Enzymes and chelating agent in cotton pretreatment

Desized cotton fabric and cotton seed-coat fragments (impurities) have been treated with commercial cellulase (Celluclast 1.5 L), hemicellulase–pectinase (Viscozyme 120 L) and xylanase (Pulpzyme HC) enzymes. Seed-coat fragments hydrolyzed much faster than the cotton fabric itself. This relative difference in hydrolysis rates makes possible a direct enzymatic removal of seed-coat fragments from desized cotton fabric. Addition of chelating agents such as ethylenediamine-tetra-acetic acid (EDTA) markedly enhanced the directed enzyme action. Pretreatments carried out in acidic solution at pH 5 increased the lightness of seed-coat fragments, contrary to the samples treated in neutral medium at pH 7. Alkaline scouring resulted in darker seed-coat fragments except for the samples pretreated with Pulpzyme HC plus EDTA. This effect is similar to that observed in the biobleaching process in pulp and paper industry.

Microstructure of the processing of black beans (Phaseolus vulgaris L.) from purée to drum‐dried flakes

AbstractBlack bean purée and drum‐dried flake microstructures were studied and compared with raw bean by light and scanning electron microscopies. Results illustrate the value of microscopy as a tool for evaluating physical and chemical changes in bean components due to processing. Microscopy was employed to follow the microstructural changes during the processing of black beans by looking at the intermediate product (the purée) and the end product (the flake). The consequences of processing on storage components such as starch, proteins, lipids, and cell walls were elucidated. The bean purée contained starch granules within intact cells and seed coat fragments throughout the product. The drum‐dried flakes had a rough exterior, and starch granules were also found within intact cells. Both starch granules and seed coat fragments were found in the drum‐dried flake matrices. Protein bodies, occurring in the raw bean, were present (but less obvious than in the raw bean) in both the bean purée and the drum‐dried flake. Cell contents that no longer occurred in intact cells consisted of fused protein bodies in both products. The seed coat did not change significantly during processing, and pieces of seed coat were easily differentiated throughout the bean purée and the drum‐dried flakes. The endosperm, which is closely adherent to the inner portion of the seed coat in the intact bean, was no longer evident in the processed samples, presumably because the endosperm tissue had completely solubilized following the addition of water. Lipids occurred as small droplets and were located throughout both the bean purée and the drum‐dried flakes. The bean purée consisted mostly of clumps of intact cotyledon cells with very few broken cells. The cotyledon cells contained intact starch granules with no evidence of starch gelatinization [i.e., the irreversible breakdown of the granule structure (Dengate 1984)]. Free starch granules in the purée, resulting from broken cells, were slightly swollen and had begun to gelatinize. Protein bodies were still evident in the purée, but no longer stained as in the raw, mature bean. The drum‐dried flakes contained intact and broken cotyledon cells. Intact cells contained protein bodies that were difficult to detect and appeared to be a rather continuous protein matrix. The cotyledon cells also contained partially gelatinized starch granules that remained mostly distinct but were beginning to fuse. Starch granules interspersed between intact cells were fused and completely gelatinized. The drum‐dried flake matrix consisted of a continuous mixture of protein, starch, and cell wall material.

Combining Traditional Cotton Scouring with Cellulase Enzymatic Treatment

The action of a cellulase enzymatic pretreatment in the efficient alkaline scouring of cotton fabrics is studied and reported in this work. Improved removal of seed-coat fragments is the primary goal of the experiments, and spinning blowroom waste, rich in seed-coat fragments, is the main target substrate for enzymatic studies. Commercially available cellulase enzyme, a complex mixture of cellulase components (endo- and exoglucanases, beta-glucosidase) and accompanying enzymes (e.g., hemicellulases. pectinases ), is used throughout the experiments. Depending on time and enzyme con centration, 28-34% of the spinning blowroom waste can be hydrolyzed by cellulase. With consecutive cellulase treatment and traditional pad-steam scouring, weight loss is as high as 78-86%. Alkaline cotton scouring (control) results in only 66% weight loss. The cellulase enzyme complex makes the residual seed-coat fragments more ac cessible to scouring chemicals. The effect of enzymatic treatment on seed-coat fragment removal from desized cotton fabric is also significant. As photomicrographs show, the tiny fibers that attach the seed-coat fragments to the fabric are hydrolyzed by the enzyme, facilitating removal of these impurities from the fabric surface.

PROCESSING COTTON CULTIVARS WITH CONVENTIONAL GIN MACHINERY

Cleaning, drying, and ginning cotton cultivars on conventional ginning equipment produces commerciallyuseful information for comparative purposes. Evaluation of numerous cultivars grown in Mississippi in two years ondifferent soil types indicated substantial differences between the cultivars in terms of monetary returns to the farmer andfiber properties important to the textile industry. In 1994, gross monetary returns averaged $1,097.71 per hectare andranged from about $957.92 to $1,258.19; classers color was generally Middling grade but leaf ranged from 1.3 to 3.3;the number of neps averaged 289 and ranged from 209 to 381 per gram of lint; seed-coat fragments (SCFs) averaged59.6 and ranged from 44 to 116 per 3 g of lint; and short fiber content (SFC) by weight averaged 8.0% and ranged from5.4% to 11.2%. Similar results occurred in 1993, unfortunately, the best characteristics were not all present in thecultivars that yielded the highest monetary return. These results show the potential for improving cotton fiber qualityparameters but care must be exercised to ensure that all growth conditions are considered.

Cottonseed Moisture and Seed Damage at Gins

Cottonseed merchants are concerned about damage to cottonseed that occurs at the cotton gin. Because of these concerns a two-year study was conducted to determine the effect of cottonseed moisture levels and seed cotton feedrates during ginning on cottonseed damage and the occurrence of seed coat fragments (SCF) in the lint. Five cottonseed moisture levels were tested the first year whereas four were used the second year. Two feedrate levels were considered each year. During the first-year experiment, the higher feedrate gave significantly higher seed damage while the SCF count only showed a higher trend. However, neither seed damage nor SCF numbers were significantly affected by the feedrates in the second-year experiment although both parameters tended to be higher for the higher feedrate. Seed damage increased with moisture content with the largest increase occurring at seed moisture levels above 12%. Seed coat fragment numbers and weights in ginned lint tended to be larger for the higher moisture contents. The study indicated cottonseed was more susceptible to damage at higher moisture contents and that high feedrates seem to accelerate the damage process.

Further Comments on "Lint Cleaning Effect on Seed-Coat Fragment Size Distribution in Cotton"

Further Comments on "Lint Cleaning Effect on Seed-Coat Fragment Size Distribution in Cotton"

Seed Coat Fragments in Cotton Yarns

Five Acala cottons, two with high and three with low seed coat fragment counts, were included in a study of fiber properties to determine plausible causes of the pro pensity for certain cultivars to produce a high seed coat fragment count. Physical properties were determined and compared for each variety grown in three locations.

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