Clava Tunic Research Articles

Selenium-loaded cellulose film derived from Styela clava tunic accelerates the healing process of cutaneous wounds in streptozotocin-induced diabetic Sprague–Dawley rats

Purpose: Aims of this study is to evaluate the therapeutic effects and toxicity of Se-loaded cellulose film originated from Styela clava tunic (SeSCTF) on cutaneous wounds during diabetic conditions.Materials and methods: Alterations in skin regeneration, angiogenesis and toxicity were examined using streptozotocine (STZ)-induced diabetic Sprague Dawley® (SD) rats with surgical skin wounds after application of SeSCTF for 12 days.Results: SCTF showed high tensile strength (1.64 MPa), low elongation (28.59%), low water vapor transmission rate (WVTR) and outstanding porous structure. Although SeSCTF application did not induce any significant alterations in glucose concentration or toxicity, wound morphology was rapidly recovered in the SeSCTF treated group relative to the gauze (GZ) and SCTF treated group. Moreover, recovery of re-epithelization, wound contraction and number of blood vessel was observed in SeSCTF treated groups when compared with all other groups. Furthermore, the SeSCTF treated group showed complete recovery of key protein expressions of the downstream signaling pathway of vascular endothelial growth factor (VEGF), angiopoietin-2/1 (Ang-2/1), the signaling pathway of insulin receptors and anti-oxidative status.Conclusions: Overall, the results of this study suggest that SeSCTF accelerates the healing process of cutaneous wounds in STZ-induced diabetic SD rats through stimulation of angiogenesis and the glucose receptor signaling pathway.

미더덕껍질과 천연고분자 혼합물을 이용한 마스크팩시트의 제조방법

Ultraviolet radiation have much influenced with a deep wrinkles, roughness, laxity of skin damage and pigmentation through oxidative stress and oxidative photo-damage. This study investigates the functional properties of hydrogel facial mask sheets made from agar, Styela clava tunics and Broussonetia papyrifera tunics. The skin of S. clava is covered with a hard cellulose containing glycoprotein, glycosaminoglycan and chondroitin sulfate. B. papyrifera is better known as Paper mulberry. It contains kazinol which serves as a tyrosinase inhibitor and skin whitening agent. The tensile strength of facial mask sheet was measured by universal testing machine, and the water absorption and moisture permeability of facial mask sheet were measured by dryer. Additionally, the DPPH assay and MTT assay were conducted for anti-oxidative activity and cytotoxicity of facial mask sheet. The whitening effect of the facial mask sheet was measured by tyrosinase inhibitor assay. These tests showed that the three ingredients are suitable cosmetic materials. The results reveal that they produce a high quality hydrogel facial mask sheet when the membrane contains 1%(W/V) of agar, 0.1%(W/V) of B. papyrifera tunics and 0.05%(W/V) of S. clava tunics.

Effects of different cellulose membranes regenerated from Styela clava tunics on wound healing.

The aim of this study was to investigate the therapeutic effects of three different cellulose membranes (CMs) manufactured from Styela clava tunics (SCTs) on the healing of cutaneous wounds. We examined the physical properties and therapeutic effects of three CMs regenerated from SCTs (referred to as SCT- CMs), including normal CM (SCT-CM), freeze-dried SCT-CM (FSCT-CM) and sodium alginate-supplemented SCT-CM (ASCT-CM) on skin regeneration and angiogenesis using Sprague-Dawley (SD) rats. FSCT-CM exhibited an outstanding interlayered structure, a high tensile strength (1.64 MPa), low elongation (28.59%) and a low water vapor transmission rate (WVTR) compared with the other SCT-CMs, although the fluid uptake rate was maintained at a medium level. In the SD rats with surgically wounded skin, the wound area and score of wound edge were lower in the FSCT-CM-treated group than in the gauze (GZ)-treated group on days 3–6 and 12–14. In addition, a significant attenuation in the histopathological changes was observed in the FSCT-CM-treated group. Furthermore, the expression level of collagen-1 and the signaling pathway of transforming growth factor (TGF)-β1 were significantly stimulated by the topical application of FSCT-CM. However, no signs of toxicity were detected in the livers or kidneys of the three SCT-CM-treated groups. Overall, our data indicate that the FSCT-CM may accelerate the process of wound healing in the surgically wounded skin of SD rats through the regulation of angiogenesis and connective tissue formation without inducing any specific toxicity.

Ethanol extracts collected from the Styela clava tunic alleviate hepatic injury induced by carbon tetrachloride (CCl4) through inhibition of hepatic apoptosis, inflammation, and fibrosis.

The Styela clava tunic (SCT) is known as a good raw material for preparing anti-inflammatory compounds, wound healing films, guided bone regeneration, and food additives. To investigate whether ethanol extracts of the SCT (EtSCT) could protect against hepatic injury induced by carbon tetrachloride (CCl4) in ICR mice, alterations in serum biochemical indicators, histopathology, hepatic apoptosis, inflammation, and fibrosis were observed in ICR mice pretreated with EtSCT for 5 days before CCl4 injection. EtSCT contained 15.6 mg/g of flavonoid and 37.5 mg/g phenolic contents with high 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (93.3%) and metal chelation activity (46.5%). The EtSCT+CCl4-treated groups showed decreased levels of ALT, LDH, and AST, indicating toxicity and a necrotic area in the liver, while the level of ALP remained constant. The formation of active caspase-3 and enhancement of Bax/Bcl-2 expression was effectively inhibited in the EtSCT+CCl4-treated groups. Furthermore, the levels of pro- and anti-inflammatory cytokines and the phosphorylation of p38 in the TNF-α downstream signaling pathway rapidly recovered in the EtSCT+CCl4-treated groups. The EtSCT+CCl4-treated groups showed a significant decrease in hepatic fibrosis markers including collagen accumulation, MMP-2 expression, TGF-β1 concentration, and phosphorylation of Smad2/3. Moreover, a significant decline in malondialdehyde (MDA) concentration and enhancement of superoxide dismutase (SOD) expression were observed in the EtSCT+CCl4-treated groups. Taken together, these results indicate that EtSCT can protect against hepatic injury induced by CCl4-derived reactive intermediates through the suppression of hepatic apoptosis, inflammation, and fibrosis.

Protective effects of the antioxidant extract collected from Styela clava tunics on UV radiation-induced skin aging in hairless mice

Ultraviolet(UV) radiation is considered a primary cause of skin damage, which is characterized by deep wrinkles, roughness, laxity and pigmentation through oxidative stress and oxidative photodamage. To examine the therapeutic effects of ethanol extract of Styelaclava tunics(EtSCT) on UV radiation-induced skin aging in hairless mice, alterations in skin phenotype, histological structures, inflammation, endoplasmic reticulum(ER) stress, oxidative conditions and toxicity were investigated during 13weeks of UV irradiation and topical application of EtSCT. EtSCT showed high reducing power (3.1%), 2,2-diphenyl-1-picrylhydrazyl(DPPH) radical scavenging activity (92.7%) and NO scavenging activity (15.6%) due to its high total flavonoids (15.3mg/ml) and total phenolics (36.8mg/ml). The topical application of EtSCT suppressed photoaging of the skin of UV-irradiated mice, and this was demonstrated by the inhibition of wrinkle formation, the suppression of the erythema index as well as the prevention of transepidermal water loss. Additionally, the epidermal thickness and adipocytes number were recovered to a similar level as that in the no radiation group in the UV+EtSCT‑treated groups compared with the UV+vehicle‑treated group, and the expression of collagenI increased. The attenuation of mitogen‑activated protein kinase and ERstress signaling pathways activated by reactive oxygen species was also detected in the UV+EtSCT‑treated group. Inflammatory responses including the infiltration of mast cells, CD31expression and interleukin-6 secretion were significantly lower in the UV+EtSCT-treated groups. Moreover, the concentration of malondialdehyde was reduced and the activity of superoxide dismutase was effectively recovered in the UV+EtSCT-treated groups compared with that in the vehicle-treated groups. Liver and kidney toxicity factors were maintained at a constant level. These results suggest that EtSCT has the potential for use as therapeutic drug which protects against skin aging by regulating the skin morphology, histopathological structures, ER stress, inflammation and oxidative conditions.

고분자필름과 금속막 의료소재에 대한 생체적합성 및 독성 평가를 위한 새로운 세포배양시스템의 개발 및 적용

고분자(polymer), 금속(metal), 세라믹(ceramic), 합성물(composite) 등과 같은 바이오소소재(Biomaterials)는 그들의 물리화학적 성질 때문에 의료용섬유(medical fibers), 인공혈관(artificial blood vessels), 인공관절(artificial joints), 임플란트(implants), 연조직(soft tissue), 인공성형물(plastic surgery materials) 등 의료용으로 많이 사용되며, 개발연구도 활발히 진행되고 있다. 그러나, 필름(film)이나 판(plate)형태의 바이오소재에 대한 생체적합성(biocompatibility)이나 독성(toxicity)을 포유동물세포를 이용하여 평가하는 것은 적절한 평가용 장치가 없기 때문에 매우 어려운 상황이다. 따라서 이러한 문제를 해결하기 위해서, 본 연구에서는 고분자필름이나 금속판에 유용하게 적용할 수 있는 실리콘링, 상판(top panel), 하판(bottom panel)으로 구성된 새로운 포유동물배양시스템을 개발하고, 이를 실제 적용하고자 하였다. 개발된 시스템은 평가하고자 하는 시료를 상판과 하판사이에 조립하는 샌드위치시스템을 기반으로 한다. 세포배양장치의 조립 후, SK-MEL-2세포를 3가지 시료; Styela Clava Tunic (SCT)- PF, NaHCO₃-added SCT (SCTN)-PF, magnesium MP (MMP)에 적용하고 37℃ 이산화탄소 배양기에서 24시간과 48시간 동안 배양하였다. MTT분석결과에서, 세포생존율(cell viability)은 24시간과 48시간 동안 SCT-PF배양그룹에서 정상적으로 유지되었지만 48시간 동안 SCTN-PF배양그룹에서는 급격하게 감소되었다. 더불어, MMP배양그룹에서 세포생존율은 24시간과 48시간 배양 후에 대조군과 유사하게 유지되었다. 이러한 결과는 본 연구에서 새롭게 개발된 샌드위치형태의 포유동물세포배양장치는 고분자필름이나 금속판형태의 바이오소재에 대한 독성이나 생체적합성을 평가하기 위한 우수한 잠재력을 보유하고 있음을 제시하고 있다. Biomaterials including polymer, metal, ceramic, and composite have been widely applied for medical uses as medical fibers, artificial blood vessels, artificial joints, implants, soft tissue, and plastic surgery materials owing to their physicochemical properties. However, the biocompatibility and toxicity for film- and plate-form biomaterials is difficult to measure in mammalian cells because there is no appropriate incubation system. To solve these problems, we developed a novel mammalian cell culture system consisting of a silicone ring, top panel, and bottom panel and we applied two polymer films (PF) and one metal plate (MP). This system was based on the principal of sandwiching a test sample between the top panel and the bottom panel. Following the assembly of the culture system, SK-MEL-2 cells were seeded onto Styela Clava Tunic (SCT)-PF, NaHCO₃-added SCT (SCTN)-PF, and magnesium MP (MMP) and incubated at 37℃ for 24 hr and 48 hr. An MTT assay revealed that cell viability was maintained at a normal level in the SCT-PF culture group at 24 or 48 hr, although it rapidly decreased in the SCTN-PF culture group at 48 hr. Furthermore, the cell viability in the MMP culture group was very similar to that of the control group after incubation for 24 hr and 48 hr. Together, these results suggest the sandwich-type mammalian culture system developed here has the potential for the evaluation of the biocompatibility and toxicity of cells against PF- and MP-form biomaterials.

알칼리처리에 따른 미더덕 껍질의 이화학적 특성

This study was performed to evaluate the effect of alkaline treatment on Styela clava tunic (SCT). Considerable damage to the surface of alkali-treated SCT was observed by scanning electron microscopy (SEM) in a concentration-dependent manner upon alkaline treatment. The amount of crystalline region in SCT gradually increased with increasing NaOH concentration, which was analyzed by X-ray diffraction and thermogravimetric analysis. The initial enzymatic reaction of Celluclast toward SCT was elevated by treatment with NaOH up to 1.0 N concentration due to disruption of the SCT surface by promoting binding of enzymes with SCT. However, in the late stage of the enzyme reaction, hydrolysis rate decreased with elevation of NaOH concentration, thereby increasing the amount of non-reacted residuals. This result was due to the increase in the crystalline regions in SCT.

Stalked sea squirt (Styela clava) tunic waste as a valuable bioresource: Cosmetic and antioxidant activities

The aim of this study was to assess the skin aging related-enzyme inhibitory effects and antioxidant effects of different solvent extracts of the tunics of the solitary ascidian tunicate Styela clava, which are regarded as fishery waste. All extracts dose-dependently inhibited the enzyme activities of collagenase, elastase and hyaluronidase. The anticollagenase activities (IC50) of hot water (5.058mg/ml) and n-butanol (5.760mg/ml) extracts were comparable to that of ascorbic acid (3.838mg/ml), but lower than that of EDTA (10.856mg/ml). The antielastase activities (IC50) of ethanol (0.356mg/ml), acetone (1.668mg/ml), and n-butanol (2.040mg/ml) extracts were much lower than that of ursolic acid (4.073mg/ml), a representative elastase inhibitor, and the antihyaluronidase activities of ethyl acetate (0.210mg/ml) and hexane (0.596mg/ml) extracts were lower than that of ketoprofen, a well-known hyaluronidase inhibitor. Hot water extract scavenged ABTS radicals with an IC50 value of 0.192mg/ml, which was comparable to that of ascorbic acid (0.052mg/ml). These results suggest that S. clava tunics (SCTs) are a potential candidate for wrinkle-care cosmetics and for the treatment of inflammation-related disorders. As far as we are aware, this is the first report to describe the potential antiaging activity of SCT.

수산폐기물인 미더덕껍질 용매 추출물의 항산화 및 항고혈압 활성

Styela clava tunic is generated in large amounts as a waste from S. clava processing plants and leads to environmental problems. It destroys the beach scenery and causes a bad smell and pollution by trashing on the seashore. Therefore, purpose of this study was to investigate antioxidant and antihypertensive activities of different solvent extracts from S. clava tunic for recycling of fishery waste. Antioxidant and antihypertensive activities of all extracts were concentration-dependent. Of extracts, hot water extract showed the highest DPPH radical scavenging activity with the lowest effective concentration (<TEX>$EC_{50}$</TEX>) value (0.733 mg/ml). Chloroform extract exhibited the highest metal chelation activity with the lowest <TEX>$EC_{50}$</TEX> value (2.696 mg/ml). Autoclaved water extract showed the highest NO radical scavenging activity with the lowest <TEX>$EC_{50}$</TEX> value (0.491 mg/ml) and n-hexane extract showed the highest reducing power (<TEX>$A_{700}=1.897$</TEX> at 100 mg/ml). And n-butanol extract showed the highest SOD-like activity with the lowest <TEX>$EC_{50}$</TEX> value (19.116 mg/ml) and ACE inhibition activity with the lowest inhibitory concentration(<TEX>$IC_{50}$</TEX>) value (0.149 mg/ml). These results indicate that extracts obtained from S. clava tunic may potential candidate to reduce diseases caused by various oxidative stresses and hypertension.

미더덕껍질 셀룰로오스의 매립 생분해성에 대한 연구

To investigate the biodegradation of the cellulose powder(CP) derived from Styela clava tunics(SCT), some physico-chemical properties and biodegradability of SCT-CP were measured after the incubation for 45 days. The particles size of SCT-CP prepared with washing, bleaching, drying, and grinding processes was 150-400μm although most of particles (70%) was more than 400μm. The cellulose structures of SCT-CP detected using the X-ray diffraction and DSC analysis was very similar with that of wood pulp powder(WP-CP). The glass transition temperature was not detected in both samples. Furthermore, more than 90% of the SCT-CP was degraded, whereas only over 70% of the WP-CP was degraded after the incubation for 45 days. Therefore, these results suggest the possibility that SCT-CP is particularly applicable to prepare medical fiber and film for disease treatment.

흡수성이 우수한 창상치료용 미더덕껍질 셀룰로오스필름의 제조 및 특성 분석

To establish the optimal conditions for the manufacture of high absortive cellulose film(CF) originated from Styela clava tunic(SCT), the physicochemical properties included absorption was measured in CFs prepared under the various conditions. The highest absorption was observed for SCT-CF20 prepared from the cellulose solution dissolved at 80°C for 20min, although the filtration treatment did not induce any significance alteration. Also, the absorption was higher in SCT-CF20-F prepared by the freeze drying than SCT-CF20-N(ambient air drying) and SCT-CF20-H(heat drying). The addition of porogen(NaHCO3) induced an increase of absorption in SCT-CF20-PF relative to SCT-CF20-F, while the number of interconnected porous structures was enhanced in SCT-CF20-PF. Furthermore, a high level of SK-MEL-2 cells viability was observed in SCT-CF20-PN and SCT-CF20-PF cultured group. These results show that SCT-CF may have high absorption and biocompatibility when prepared from SCT cellulose solution dissolved at 80°C for 20min after addition of porogen and then subjected to freeze drying.

Toxicity of antioxidative extract collected fromStyela clavatunics in ICR mice

Some polymers and bioactive compounds derived from Styela clava tunic (SCT) have been reported as traditional medicine for the treatment of inflammation, oxidative stress and surgical wounds although there is little scientific evidence of their liver and kidney toxicity. To investigate the toxicity of ethanol extracts of SCT (EtSCT) in the liver and kidney of ICR mice, alterations in related markers including body weight, organ weight, urine composition, liver pathology and kidney pathology were analyzed following oral administration of 50 and 100 mg/kg body weight/day of EtSCT for 14 days. EtSCT showed a high level of free radical scavenging activity for DPPH (93.1%) and NO (16.2%) as well as the presence of 14.8 mg/mL of flavonoids and 36.2 mg/mL of phenolics, while EtSCT treated groups did not show any significant alterations in the body and organ weight, clinical phenotypes, urine parameters or mice mortality when compared with the vehicle treated group. In addition, constant levels of serum biochemical markers including alanine phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN) and serum creatinine (CRE) were maintained. Moreover, no specific histopathological features induced by most toxic compounds were observed in liver and kidney sections stained with hematoxilin and eosin. Therefore, the present results indicate that EtSCT with strong antioxidant activity cannot induce any specific toxicity in liver and kidney organs of ICR at doses of 100 mg/kg body weight/day.

미더덕 껍질, 뽕잎, 양파 추출물을 첨가한 항고혈압 저염간장의 제조 및 특성

고혈압과 같은 혈관성 질환을 개선할 수 있는 항고혈압 저염간장을 개발하기 위하여 미더덕 껍질, 뽕잎, 양파 추출물을 저염간장(염도 12%)에 첨가하였다. 그 결과 단일 소재 추출물을 첨가하였을 때보다 두 가지 이상을 혼합하여 첨가하였을 때 높은 ACE 저해능과 DPPH 라디칼 소거능을 나타내었다. 특히 미더덕 껍질과 양파의 추출물들을 첨가한 저염간장에서 ACE 저해능과 DPPH 라디칼 소거능이 기존의 일반 염도인 15% 간장에 비하여 상대적으로 약 30% 향상되었다. 이상의 결과는 미더덕 껍질, 뽕잎, 양파의 추출물들이 항고 혈압능과 항산화능에 유익한 저염간장을 제조할 수 있는 유익한 소재로 활용될 수 있음을 시사한다.

미더덕껍질의 유수추출물이 과산화수소에 의해 유발된 HepG2간암세포의 세포사멸에 미치는 보호 효과

Styela Clava tunic (SCT) has found some applications in many areas of medical treatment including as an anti-inflammatory compound, a wound healing film, in guided bone regeneration, and as a food additive. The protective effect of SCT aqueous extract (AE-SCT) on cell death induced by H₂O₂ treatment was investigated by measuring the changes in cell viability in HepG2 cells after AE-SCT treatment. High concentrations of antioxidant compounds including flavonoids (3.3 mg/g) and phenolics (32.3 mg/g) were detected in AE-SCT but no significant cytotoxicity was observed in HepG2 cells treated with AE-SCT. The viability of HepG2 cells was also not changed by treatment with different concentrations of AE-SCT after H₂O₂ treatment. However, cell viability was significantly increased in cells treated with three different concentrations of AE-SCT before H₂O₂ treatment. The greatest increase in cell viability was observed in the group treated with 50 μg/ml AE-SCT, when compared with vehicle-treated group. FACS and DAPI staining analysis indicated that the decrease in number of dead cells was dependent on the concentration of AE-SCT. Alterations in the Bax/Bcl-2 ratio after H₂O₂ treatment were significantly restored by treatment with different concentrations of AE-SCT. These results indicate that AE-SCT, which contains high levels of antioxidants, may protect cells against death induced by H₂O₂ treatment.

Cellulose film regenerated from Styela clava tunics have biodegradability, toxicity and biocompatibility in the skin of SD rats

Cellulose is one of the most widespread biomolecules in nature and has been exploited in various applications including scaffolding, tissue engineering, and tissue formation. To evaluate the biocompatibility of cellulose film manufactured from Styela clava tunics (SCT-CF), these films were implanted in Sprague-Dawley (SD) rats for various lengths of time, after which they were subjected to mechanical and biological analyses. The cellulose powders (12-268 m) obtained from SCT was converted into films via casting methods without adding any additives. SCT-CF contained about 98 % α-cellulose and very low concentrations of ββ-cellulose. Additionally, the crystallinity index (CrI) of SCT-CF was lower (10.71 %) than that of wood pulp-cellulose films (WP-CF) (33.78 %). After implantation for 90 days, the weight loss and formation of surface corrugations were greater in SCT-CF than that of WP-CF, while the surface roughness was significantly higher in WP-CF than SCT-CF. However, there were no differences in the number of white blood cells between SCT-CF implanted rats and vehicle implanted rats. The level of metabolic enzymes representing liver and kidney toxicity in the serum of SCT-CF implanted rats was maintained at levels consistent with vehicle implanted rats. Moreover, no significant alteration of the epidermal hyperplasia, inflammatory cell infiltration, redness, and edema were observed in SD rats implanted with SCT-CF. Taken together, these results indicate that SCT-CF showed good degradability and non-toxicity without inducing an immune response in SD rats. Further, the data presented here constitute strong evidence that SCT-CF has the potential for use as a powerful biomaterial for medical applications including stitching fiber, wound dressing, scaffolding, absorbable hemostats and hemodialysis membrane.

수산폐기물 재활용을 위한 미더덕껍질 용매 추출물의 생리활성 탐색

Styela clava tunic is generated in large amounts as a waste from S. clava processing plants and causes environmental problem. Although biological activities of S. clava were reported by many investigators, study on S. clava tunic was little. In this study, therefore, tyrosinase inhibition and antioxidative activities of extracts from S. clava tunic using different solvent were investigated for recycling of the fishery waste. Among extraction methods tested, autoclaved extraction (25.7%) and hot water extraction (18.2%) appeared to be effective for extraction. The highest total phenolic content was 46.6 mg/g in autoclaved extract while the highest flavonoid content was 23.0 mg/g in chloroform extract. All extracts possessed tyrosinase inhibition activity and the inhibition activity was concentration-dependent. Inhibition concentration (<TEX>$IC_{50}$</TEX>) against tyrosinase activity was <TEX>$0.36{\times}10^4$</TEX> mg/ml in ethanol extract, <TEX>$0.11{\times}10^3$</TEX> mg/ml in acetone extract and 0.27 mg/ml in n-butanol extract. Among extracts tested, hot water and autoclaved extracts displayed higher antioxidative activity than organic solvent extracts. Therefore, our data suggest that extract from S. clava tunic may potential candidate for cosmetic product with whitening effect and medicine for diseases caused by various oxidative stresses.

미더덕 껍질 추출물을 함유한 곤약의 제조 및 품질 분석

Styela (S.) clava (Korean name: miduduk) tunic is produced as a by-product after processing of S. clava. For utilizing this tunic, a konjac containing the tunic extracts was prepared and the qualities evaluated for their color, textural properties, and sensory attributes. The tunic extract was prepared by boiling tunic with water, followed by filtration through filter paper. Significant 2,2`-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activity was found in the tunic extract. Increasing the concentration of tunic extract in the konjac tended to decrease lightness (L) and increase the redness (a) and the yellowness (b) of the konjac. The strength and hardness of the konjac increased with increasing concentrations of the tunic extract. All test samples with a 3 mm thickness had good flexibility and did not break even after 4 times folds. In sensory evaluations, the konjac containing 25% S. clava tunic extracts acquired a relatively higher score. The results suggest that S. clava tunic can be applied to konjac products to improve their quality and functionality.

미더덕 껍질 분말을 함유한 어묵의 제조 및 품질 분석

Styela clava (Korean name: miduduk) tunic was produced as a byproduct after processing of S. clava. To utilize S. clava tunic, fish paste containing tunic powder was prepared, and quality characteristics were evaluated for color, textural properties, and sensory attributes. Increasing the amount of S. clava tunic in fish paste tended to decrease lightness (L), redness (a), and yellowness (b) values of the surface part of fish paste. Strength and hardness of fish paste increased with increasing amount of tunic. All test samples with 3 mm thickness showed good flexibility and did not break even after folding in half four times. For overall acceptance in the sensory evaluation, fish paste containing 1% S. clava tunic acquired a relatively higher score. These results suggest that S. clava tunic can be applied to fish paste products to improve quality and functionality.

미더덕 껍질과 PVA를 혼합한 재료로부터 제조한 복합섬유의 제법과 성질(II)

Regenerated composite fibers are prepared from solution(styela clava tunics /poly vinyl alchol) using N-methylmorpholine-N-oxide(NMMO)/water(87/13)(wt/wt) as a solvent by dry-wet spinning. The chemical cellulose (94%, -cellulose content) used for this study is extracted from styela clava tunics (SCT, Midduck), which are treated in chemical process and mechanical grinding. The structure and physical properties of regenerated composite fibers were investigated through IR-spetra, DSC, TGA and SEM. The optimal blend ratio of SCT/PVA for spinning solution was 70/30 and the total weight was 4% concentrations in NMMO/water solvent system. The fiber density, moisture contents and the degree of swelling were 10.2(%) and 365(%), respectively. The crystallinity index of composite fibers are decreased as the PVA contents increased. Thermal decomposition of composite fibers took place in two stages at around and . The best thermal stability was obtained with 30% PVA contents.

Chondroitin sulfate extracted from the Styela clava tunic suppresses TNF-α-induced expression of inflammatory factors, VCAM-1 and iNOS by blocking Akt/NF-κB signal in JB6 cells

Inflammatory mediators are known to play a key role in tumorigenesis, therefore, it is a promising strategy to inhibit the inflammation for cancer prevention and/or treatment. Current study was performed to investigate the effects of chondroitin sulfate (CS) extracted from Styela clava tunic on TNF-α-induced inflammation and to elucidate the mechanism of CS on the regulation of inflammatory factors in JB6 cells. Our results showed that CS inhibited TNF-α-induced NF-κB activation and subsequent vascular cell adhesion molecule 1 and inducible nitric oxide synthase expressions by blocking Akt signals in JB6 cells. Our results suggest that CS may be developed as an effective anti-inflammatory agent in the future.