Silk Floss Research Articles

"Needle" hidden in silk floss: Inactivation effect and mechanism of melamine sponge loaded bismuth oxide composite copper-metal organic framework (MS/Bi2O3@Cu-MOF) as floating photocatalyst on Microcystis aeruginosa

Photocatalytic technology showed significant potential for addressing the issue of cyanobacterial blooms resulting from eutrophication in bodies of water. However, the traditional powder materials were easy to agglomerate and settle, which led to the decrease of photocatalytic activity. The emergence of floating photocatalyst was important for the practical application of controlling harmful algal blooms. This study was based on the efficient powder photocatalyst bismuth oxide composite copper-metal organic framework (Bi2O3 @Cu-MOF), which was successfully loaded onto melamine sponge (MS) by sodium alginate immobilization to prepare a floating photocatalyst MS/Bi2O3 @Cu-MOF for the inactivation of Microcystis aeruginosa (M. aeruginosa) under visible light. When the capacity was 0.4g (CA0.4), MS/Bi2O3 @Cu-MOF showed good photocatalytic activity, and the inactivation rate of M. aeruginosa reached 74.462% after 120h. MS/Bi2O3 @Cu-MOF-CA0.4 showed a large specific surface area of 30.490m2/g and an average pore size of 22.862nm, belonging to mesoporous materials. After 120h of treatment, the content of soluble protein in the MS/Bi2O3 @Cu-MOF-CA0.4 treatment group decreased to 0.365mg/L, the content of chlorophyll a (chla) was 0.023mg/L, the content of malondialdehyde (MDA) increased to 3.168 nmol/mgprot, and the contents of various antioxidant enzymes experienced drastic changes, first increasing and then decreasing. The photocatalytic process generated·OH and·O2-, which played key role in inactivating the algae cells. Additionally, the release of Cu2+ and adsorption of the material also contributed to the process.

Inclusion Complex, Antioxidant, and Antimicrobial Properties of Silk Floss Sheet Modified with ß-Cyclodextrin and Loaded with Herbal Essential Oils as a Green Tissue

Inclusion Complex, Antioxidant, and Antimicrobial Properties of Silk Floss Sheet Modified with ß-Cyclodextrin and Loaded with Herbal Essential Oils as a Green Tissue

Comparison of dental flosses – an investigation of subjective preference and mechanical properties

Objective To investigate the properties (tensile strength, roughness, abrasiveness) of different dental flosses and how these properties relate to subjective preference for floss by users. Materials and method Four flosses of differing compositions were selected (polytetrafluoroethylene (PTFE), nylon, silk, and ultra-high-molecular-weight polyethylene (UHMWPE)). Tensile strength (TS) was measured utilising a universal testing machine (total n = 40). Surface roughness (Ra) was measured on 3D reconstructed models of scanning electron microscope and abrasiveness was measured through block-on-ring tests against human enamel. Subjective preference for floss was measured by asking a sample of 16 individuals to use each floss for an 8-day period using a split-mouth design. Results The highest TS was found in UHMWPE floss (194.18 ± 24.61 MPa) while the lowest TS was found in PTFE floss (11.78 ± 0.77 MPa). Silk floss had the highest Ra (0.304 ± 0.025 µm) while PTFE floss had the lowest (0.048 ± 0.003 µm). In-vitro abrasion testing of the flosses identified no significant differences between the flosses in causing wear on tooth enamel. Subjective ratings of flosses indicated PTFE floss to be most preferred and nylon floss to be least preferred. Conclusion There was a difference in subjective preference between dental flosses composed of different materials. The PTFE floss was the overall most preferred while the nylon floss was the least preferred. There was also an association between the mechanical properties and preference for their usage, with PTFE floss being the most preferred but having the lowest surface roughness and tensile strength. Clinical Relevance This study compared a wide range of mechanical properties and subject preferences of commercially available dental floss. The results of this study can provide guidance for the recommendation of dental floss for oral hygiene routines.

Phytochemical Properties of Silk Floss Tree Stem Bark Extract and Its Potential as an Eco-Friendly Biocontrol Agent against Potato Phytopathogenic Microorganisms

In the current study, the ethanolic extract of the stem bark of Ceiba speciosa, the silk floss tree (SFSB), was evaluated against various phytopathogenic microorganisms, including Ralstonia solanacearum, Dickeya solani, Pectobacterium atrosepticum, P. carotovorum, Fusarium oxysporum, and Rhizoctonia solani. At 300 µg/mL concentration, the SFSB extract exhibited the highest inhibition percentages of 83.33 and 86.67 for R. solani and F. oxysporum, respectively. In addition to its antimicrobial activity, SFSB extract exhibited strong antioxidant activity (IC50 value of 140.88 g/mL). HPLC analysis of the extract revealed the presence of various phenolic acids and flavonoids. Among these compounds, naringenin (18,698.83 µg/g), chlorogenic acid (2727.49 µg/g), ferulic acid (1276.18 µg/g), syringic acid (946.26 µg/g), gallic acid (812.34 µg/g), and methyl gallate (651.73 µg/g) were found to be the most abundant constituents. GCMS analysis showed that there were antimicrobial compounds like terpenoids, benzoic acid derivatives, phthalate esters, and different fatty acids. Isopropyl myristate was the most common compound, with a relative abundance of 55.61%. To our knowledge, this is the first investigation on the phytochemical composition and antimicrobial properties of SFSB extract. Consequently, utilizing SFSB extract could hold significant potential as a sustainable and natural approach for controlling and mitigating plant diseases.

Development of Apparel Using Blocks of Phulkari Pattern

India is truly a land of wonders blessed with a myriad of cultures, customs and religions. These cultures have given us some of the best art and craft forms. One such craft is the Indian embroidery, every region in India has its own style of embroidery. A diverse yet distinct testimony of our rich cultural heritage is Phulkari of Punjab. Phulkari is considered as an important part of the trousseau in Punjab. Traditionally Phulkari embroidery were done by hand on a special type of coarser fabric known as ‘khaddar’ with untwisted silk floss called ‘Pat’, but due to some of the reasons like, time consumption & tedious process of manufacturing, usage of coarse fabric, lack of skilled labour, etc., it is not spreading & growing at a broader range. Hence in the present study an attempt was made to develop blocks of phulkari motif for printing of apparels like saree, dupatta, blouse & skirt. The motifs were collected from various sources like internet, books, etc. Selected motifs were developed into blocks by professional artists. The developed Phulkari motifs used for placement on the apparels by using Corel draw software for visual evaluation. All the developed placement of designs were coded & judged by a panel of 30 members. Four most preferred designs from each apparel are selected for final product development. Developed products were evaluated by same panel of members and ranked the product according to obtaining scores. All the developed products were highly accepted & appreciated in the evaluation.

A Study on Dye Inclusion Complex, Adsorption, and Kinetic of Silk Floss Sheet Modified with β‐Cyclodextrin as a Biodegradable Adsorbent

AbstractIn this study, the silk floss sheet (SFS) modified with β‐cyclodextrin (β‐CD) is used to adsorb various dyes (anionic: Acid Red 33/ AR33, cationic: Basic Blue 9/ BB9, and non‐ionic: Disperse Yellow 26/ DY26) from colored solutions. The various analyses (fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), ultraviolet‐visible spectroscopy (UV‐Vis), and elemental analysis) are used to study the inclusion complex between β‐CD and the mentioned dyes. In addition, the influence of experimental parameters on the adsorption process (such as dye molecular size, adsorbent dosage, initial dye concentration, contact time, and pH) is assessed. The results show that the molecular size and pH have more effect on the adsorption capacity of SFS. It is found that optimum adsorption of acid and disperse dyes occurrs at pH 4, while basic dye can adsorb at around pH 10. Also, the experimental data have a good fit with the Langmuir equation and the kinetic data can correlate with the second‐order equations. Finally, the desorption studies show that this natural adsorbent can be reused many times without any change in its adsorption capacity.

Sericin, a Versatile Protein from Silkworm - Biomedical Applications

The silkworm, Bombyx mori, which feeds solely on the leaves of the mulberry plant, produces mulberry silk. The components of Bombyx mori silk are 60-80 percent fibroin, 15-35 percent sericin and 1-5 percent non-sericin, including wax, pigments, sugars and other impurities. Silk sericin is a natural polymer that encloses and holds together two filaments of fibroin in the silk thread used in the cocoon. In the research and production of medical biomaterials and biomedicines, protein-based silk fibroin has been widely used for two decades. Sericin is often neglected and abandoned in the manufacturing of traditional silk fabrics, silk floss or synthetic silk biomaterials as a by-product or waste. However, sericin is not only a highly useful biological substance, but also has a great deal of biological activity, similar to fibroin. General characteristics of both silk proteins, fibroin and sericin, extracted from Bombyx mori silkworm, and the biological activity and possible use of sericin were addressed in this review. Due to its amino acid make-up and antioxidant properties, sericin has been used in the food and cosmetic industry. The moisturizing power provides guidance for wound healing as a therapeutic agent, protection against ultraviolet radiation, and formulation of creams and shampoos. Antioxidant activity associated with low sericin digestibility, which increases application in the medical field, such as antitumor, antimicrobial and anti-inflammatory agent, anticoagulant, works in the health of the colon, enhances constipation and, by improving plasma lipid profile, protects the body from obesity. In addition, the properties of sericin allow its application in tissue engineering and drug delivery as a culture medium and cryopreservation, demonstrating its efficient use as an essential biomaterial.

The chloroplast genome of silk floss tree (Ceiba speciosa)

Ceiba speciosa (Malvaceae), also called silk floss tree, is a beautiful and deciduous tree native to tropical and subtropical forests of South America. Its phylogenetic position remains unclear. In this study, the complete chloroplast genome sequence of C. speciosa was reported. Its chloroplast genome size was 160,360 bp, which contains a small single copy (SSC) region of 19,947 bp and a large single copy region (LSC) of 89,393 bp, and two inverted repeats (IRs) of 25,510 bp each. In total, 129 genes were annotated for the chloroplast genome, including 86 protein-coding genes, 37 tRNA genes and 8 rRNA genes. Phylogenetic analysis showed that C. speciosa was sister to Bombax ceiba.

조선후기 이후 풀솜 제작 및 주사 방적에 관한 연구

Silk floss is a type of thread made from cocoons that cannot be spun into filament yarn, made by loosening the cocoon’s fiber in warm water. Floss yarn is thread made by spinning silk floss, and the fabric woven from floss yarn is called Tojoo or Myeonjoo. The traditional techniques of spinning silk floss and floss yarn is lost; thus, Tojoo is no longer woven today. Silk floss can be made by twisting the fiber by hand, but it was made using wooden frames, bamboo frames, and traditional roof tiles in the Joseon Dynasty. The fabric was degummed using lye and perfumed oil. After seaports were opened to Western civilization and imports, wooden frames became the tool of choice. Fabric degumming was performed through a mix of lye and sodium bicarbonate—or, more accurately, only sodium bicarbonate during this time. Once synthetic detergent entered the market, a mix of synthetic detergent and sodium bicarbonate was used for this purpose. Floss silk was made to produce floss yarn or used as material for vests, military coats, and as a substitute for cotton batting in blankets.

월정사성보박물관 소장 〈수라향낭〉의 직물과 자수 연구

This paper is for the study on textile and embroidery of Embroidered incense pouch on complex gauze, housed by Woljeongsa Museum. It is the unique case which expressed pattern with embroidery on complex gauze among relics of Korea dynasty. The shape of incense pouch is square, and all fiber materials are discolored into brown. The pattern is that young boy is born from lotus, and the pattern of incense pouch is identical at the front and rear, but has symmetrical composition. For the part of embroidery, the technique of applique was used, and complex gauze of pattern and basis is different from each other. For embroidery, two pieces of Non-patterned complex gauze and Silk Tabby in the rear were used, and another fabric of plain silk was used with linings. Concerning embroidery thread, 3 kinds such as silk floss, silk twisted thread, and wrapped gold thread can be confirmed, and 5 kinds of embroidery technique such as straight stitch, satin stitch, split stitch, couching stitch, and chain couching stitch were used. It is the chain couching stitch which we can check only in the incense pouch among Korean embroidery relics, and for special embroidery technique. The similarity between fabric composition of incense pouch and embroidery technique can be found from embroidery relics in Liao Dynasty. It is estimated that the production date of incense pouch is about 10-11 century, in early Korea dynasty.

L929 cell cytotoxicity associated with experimental and commercial dental flosses

This aim of the study was to investigate the cytotoxicity of two commercial and two experimental dental flosses. Two commercial, Oral B® Essential Floss (nylon-waxed) and Thai Silk Floss (silk-waxed), and two experimental, Floss X (nylon-waxed) and Floss Xu (nylon-unwaxed) dental flosses were used. The cytotoxic assay was performed by using cell cultures (L929) which were subjected to cell viability test with methyl-tetrazolium. Each floss specimen (0.4 g) was placed in 1 ml of Minimum Essential Medium at 37°C with 5% CO2 at 100% humidity in an incubator for 24 hours. After incubation, the cell mitochondrial activity was evaluated for detecting viable cells using optical density as per the guidelines of ISO 10993-5:2009(E). Cytotoxic effects were evaluated by measuring percentage of cell viability at 3 points of time- 5 mins, 30 mins, and 1 hr. The results showed that two commercial dental flosses and Floss X had cell viability about 90% at the three time points; however, the experimental Floss Xu presented 80% cell viability at 5 min and <70% cell viability at 30 min and 1 hr. The results concluded that the commercial dental flosses and the experimental dental floss with wax tested in this study were acceptable for clinical use.

English

English

Mechanical and Physical Properties of Various Types of Dental Floss

To compare maximum load, percentage of elongation, physical characteristics of 4 types of dental floss: (1) Thai Silk Floss (silk, waxed), (2) Oral B® Essential Floss (nylon, waxed), (3) Experimental Floss Xu (nylon, unwaxed), (4) Experimental Floss Xw (nylon, waxed). Four types of floss were tested (n=30) with a Universal Testing Machine (Instron®). Each sample (30 cm long, 5 cm segment) was fixed, and pulled apart with load cell of 100 N and a test speed of 100 mm/min. Physical characteristics were investigated by digital microscope under 2.5×10 magnification, and scanning electron microscope under 1×100 and 5×100 magnification. The size of the filaments was measured in micron (μm) and the fineness was measured in Denier. For mechanical properties, the maximum load and the percentage of elongation were presented as mean ± SD. The distribution of the data was calculated by the Kolmogorov-Smirnov test. One-way ANOVA and multiple comparison (Tukey HSD) were used to analyze the differences among the groups with the level of a statistical difference at p &lt; 0.05. The maximum load of Floss Xu, Floss Xw, Oral B and Thai Silk were 47.39, 46.46, 25.38, and 23.70 N, respectively. The percentage of elongation of Oral B, Floss Xw, Floss Xu and Thai Silk were 72.43, 44.62, 31.25, and 16.44%, respectively. All 4 types of dental floss showed statistically differences in both the maximum load and percentage of elongation at p &lt; 0.05, except for maximum load between Floss Xw and Floss Xu that showed no statistically significant difference. Physical characteristics of Thai silk revealed the most disintegrated, the smallest, and the least fine filaments. Floss Xu had the highest maximum load. Oral B had the highest percentage of elongation. Wax coating on Floss X increased the elongation but had no significant effect on the maximum load. The physical characteristics of Thai Silk resulted in the lowest mechanical properties values.

Effects of alkyl polyglycoside (APG) on Bombyx mori silk degumming and the mechanical properties of silk fibroin fibre

Alkyl polyglycoside (APG), a nonionic surfactant, is often considered to be a green surfactant and is synthesized using glucose and long chain fatty alcohols. It is used as a degumming agent of Bombyx mori silk fibre in this study for the first time. We studied APG systematically in comparison to the traditional degumming methods, such as aqueous solutions of sodium carbonate (Na2CO3) and neutral soap (NS). After repeatedly boiling silk fibres in an aqueous solution of 0.25% APG three times for 30min and using a bath ratio of 1:90-120 (g/mL), sericin was completely removed from the fibre. SDS-PAGE showed that the degumming in APG did not induce an evident breakage of the silk fibroin peptide chains, including the light chain and P25 protein. The tensile properties, thermal analysis, and scanning electron microscopic (SEM) observation of the degummed fibroin fibre all show that APG is a degumming agent similar to NS and far superior to Na2CO3. These results indicate that APG is an environment-friendly silk degumming/refining agent in the silk textile industry and in the manufacture of silk floss quilts.

Utilization of Silk to the Field of Interior Wall Materials – Silk floss wall material and Silk dupion wall cloth-paper –

Utilization of Silk to the Field of Interior Wall Materials – Silk floss wall material and Silk dupion wall cloth-paper –

Quantificação e Avaliação das Principais Espécies Florestais Licenciadas no Estado do Acre de 2005 a 2012

O presente trabalho teve como objetivo avaliar, identificar e quantificar os 15 principais gêneros e espécies florestais exploradas legalmente no estado do Acre, na Amazônia brasileira, bem como analisar o número de autorizações emitidas para exploração de florestas manejadas, o volume de madeira e a área de manejo licenciada pelo Instituto de Meio Ambiente do Acre de janeiro de 2005 a agosto de 2012. Os dados coletados demonstraram que a área e o volume de madeira licenciados apresentaram um crescimento no período analisado, atingindo o ápice em 2010 e 2011, respectivamente. Os 15 principais gêneros e espécies licenciados foram: cumaru-ferro (Dipteryx spp.), garapeira (Apuleia spp.), sumaúma (Ceiba spp.), açacu (Hura crepitans L.), matamatá (Eschweilera spp.), jatobá (Hymenaea spp.), tauari (Couratari spp.), manitê (Brosimun spp.), caucho (Castilla ulei Warb.), cedro (Cedrela spp.), guariúba (Clarisia racemosa Ruiz e Pav.), faveira (Parkia spp.), copaíba (Copaifera spp.), guaribeiro (Phyllocarpus riedelii Tul.) e abiurana (Pouteria spp.).

Effect of silk protein surfactant on silk degumming and its properties.

The silk protein surfactant (SPS) first used as a silk degumming agent in this study is an amino acid-type anionic surfactant that was synthesized using silk fibroin amino acids and lauroyl chloride. We studied it systematically in comparison with the traditional degumming methods such as sodium carbonate (Na2CO3) and neutral soap (NS). The experimental results showed that the sericin can be completely removed from the silk fibroin fiber after boiling the fibers three times for 30 min and using a bath ratio of 1:80 (g/mL) and a concentration of 0.2% SPS in an aqueous solution. The results of the tensile properties, thermal analysis, and SEM all show that SPS is similar to the NS, far superior to Na2CO3. In short, SPS may be used as an environmentally friendly silk degumming/refining agent in the silk textile industry and in the manufacture of silk floss quilts.

Viability and proliferation of L929, tumour and hybridoma cells in the culture media containing sericin protein as a supplement or serum substitute.

Cell cultures often require the addition of animal serum and other supplements. In this study, silk sericin, a bioactive protein, recovered from the waste of silk floss production was hydrolysed into three pepsin-degraded sericin peptides with different ranges of molecular mass. Normal animal cells, tumour cells and hybridoma cells were cultured systematically in FBS culture media containing sericin as a supplement or serum substitute. The culture test and microscopic observation of L929 cells showed that the smaller molecular weight of the degraded sericin is most suitable for cell culture. The cell culture results showed that with the degradation of sericin, for normal mouse fibroblast L929 cells, addition of 0.75 % sericin into FBS culture medium yields cell viability that is superior to FBS culture medium alone. When all serum was replaced by sericin, cell viability in the sericin medium could reach about one half of that in FBS medium. When in a medium containing a mixture of FBS: sericin (6:4, v/v), the cell culture effect is about 80 %. For the cultures of four tumour and one hybridoma cells, regardless of the molecular weight range, these degraded sericin peptides could substitute all serum in FBS media. The cell viability and proliferation of these tumour and hybridoma cells are equivalent or superior to that in FBS medium. In other words, cell viability and proliferation of these tumour and hybridoma cells in sericin media are more preferable to serum media. The mechanism of the sericin protein to promote cell growth and proliferation will be further investigated later.

Desenvolvimento de espécies arbóreas nativas em uma área reflorestada do corredor de biodiversidade Santa Maria - PR

Objetivou-se avaliar um plantio de enriquecimento com 12 espécies arbóreas nativas da região, em uma área reflorestada do Corredor de Biodiversidade Santa Maria, localizado entre os Municípios de Santa Terezinha de Itaipu e São Miguel do Iguaçu, no Paraná. Objetivou-se, também, avaliar a persistência da espécie invasora Megathyrsus maximus (Jacq.) B. K. Simon &amp; S. W. L. Jacobs, conhecido como capim-colonião, e alterações nas características físicas e químicas do solo. As avaliações consistiram no acompanhamento mensal da mortalidade e desenvolvimento das mudas e da massa de matéria seca obtida no manejo do capim-colonião. As alterações promovidas no solo foram verificadas por meio de três coletas de solo ao longo do experimento. A mortalidade alcançou 24,38%, sendo mais acentuada nos dois primeiros meses, janeiro (11,88%) e fevereiro (5,63%). Em relação ao desenvolvimento das mudas, destacaram-se as espécies Aloysia virgata (Ruiz &amp; Pav.) Juss. (lixeira) e Ceiba speciosa (A. St.-Hil.) Ravenna (paineira), com acréscimos mensais em diâmetro de 0,80 mm e 0,60 mm e em altura de 5,80 cm e 1,74 cm, respectivamente. O controle do capim-colonião pela metodologia aplicada foi eficiente, não havendo reincidência considerável ao longo dos meses. Por meio das análises de solo, foi possível observar que a recuperação da área, mesmo que por período curto, mostrou-se eficiente na alteração das características físicas e químicas do solo, podendo ainda levar a novas modificações em decorrência do desenvolvimento das mudas.

Ultrafiltration recovery of sericin from the alkaline waste of silk floss processing and controlled enzymatic hydrolysis

Abstract This study was designed to improve the traditional scouring procedure using a solution of sodium silicate, sodium carbonate, H2O2, surfactant etc. as a refining agent for degumming machine-drawn raw silk sheet (RSS) and raw silk from the cocoon shell of the silkworm Bombyx mori. The RSS was scoured firstly in strongly alkaline electrolyzed water (SAEW, pH ≥ 11.5) consisting mainly of hydroxyl ions by boiling for 30 min and then treated by the traditional scouring procedure (without alkaline compounds), resulting in refined silk floss. The recycled SAEW containing sericin was separated by ultrafiltration into a retentate with a range of high molecular mass values accounting for 10% (w/w) of the cocoon shell and the filtrate was separated by nanofiltration into a purified H2O filtrate and a retentate containing oligopeptides and free amino acids, which can be used directly as food additives or in biological growth media. The ultrafiltration retentate was hydrolyzed by papain under three different conditions into three groups of sericin peptides with high, middle or low molecular mass. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and gel permeation high-performance liquid chromatography (GP-HPLC) showed the molecular mass of these sericin peptides was in the range 0.2–60, 0.2–30 and 0.2–15 kDa. These clean products have a variety of applications, including coating materials for surface modification, cell culture media and food additives. The procedure described here could be applied to the manufacture of silk floss quilts and the process of refining raw silk, which results in three clean products of the silk protein fibroin (i.e. stripped of sericin) and reduces environmental pollution from scouring waste containing sericin.