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Property Evaluation of Bletilla striata/Polyvinyl Alcohol Nano Fibers and Composite Dressings  [PDF]
Jia-Horng Lin,Chao-Tsang Lu,Jin-Jia Hu,Yueh-Sheng Chen,Chen-Hung Huang,Ching-Wen Lou
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/519516
Abstract: This study used nonwoven manufacture and electrospinning to create wound dressings with solid mechanical properties and hemostasis function. 10% Polyvinyl alcohol (PVA) and 5% Bletilla striata (BS) were blended into the PVA/BS solution, which can be made into nanomaterial with high specific surface area by electrospinning. The PVA/BS solution was electrospun onto the dressing matrix made of polyester (PET) and absorbent cotton (AC), forming the PVA/BS composite dressings. According to the experiment results, when the volume ratio of PVA to BS was 9?:?1, the resulting dressings had optimal fiber formation, the finest average diameter, and the lowest toxicity. 1. Introduction Wound dressings are divided into gauze dressing, synthetic dressing, and biological dressing. Gauze dressings are composed of cellulose fibers or fur, such as gauze, cotton pad, or wool. This type of dressings is used to cover the wounds for a temporal protection and needs to be changed periodically. As various polymer materials have been developed as a result of chemical industry advances, there are many products for wounds; however, they are only good for skin-layer wounds, not for deep and large wounds [1–3]. In addition, sponge-form and spray-form synthetic dressings are available in the market; the design of synthetic dressings is further improved to be double-layer and multilayer, the former of which is composed of durable outer layer and adhesive and resilient inner layer. As all the aforementioned dressings do not significantly help large and deep burns, biological dressings with better quality and functionality are thus developed. An ideal dressing has to be able to keep wounds moist, to prevent the wounds from the second injury, to absorb the oozed blood and tissue fluid, to accelerate wound healing, as well as to have good resilience, tear strength, abrasion, and biocompatibility [4–8]. Electrospinning was first developed in 1900, when people placed melted sealing wax in an electric field, and solid fibers were jetted from the high-voltage end and accumulated on collector, forming membranes. Zeleny [9] explored the behavior of fluid droplets from a metal capillary under static electricity, and Formals (1934) published a complete electrospinning manufacturing that can successfully produce polymer filaments and that obtained the patent of electrospinning in US [10–12]. Fibers made by electrospinning are much finer than those by conventional spinning, yielding a diameter varying from tens to thousands of nanometers. The most desired functionality of electrospinning is to have
Study on Seed Germination and Rapid Propagation of Bletilla striata Rchb.f.
白及种子萌发与快速繁殖技术的研究

FU Zhi-Hui,ZHANG Jian-Xia,LI Hong-Lin,YANG Bo,
付志惠
,张建霞,李洪林,杨波

植物科学学报 , 2006,
Abstract: The effects of different culture medium on the germination rate and time of Bletilla striata Rchb.f.(Orchidaceae) seeds in different developmental phases,and multiplication of cluster shoots and rootage of plantlets was investigated.The results showed that the germination rate was positively correlated with the embryo age and the embryo rate of seeds,whereas the germination time was passively correlated with them.For the seeds with 16-week embryo age,the germination rate could be reach 84% on the medium added with 1 g/L Huabao-1 and 2 g/L Huabao-2.The germination rate of the seeds with embryo age more than 20 weeks wasn't affected by the culture medium element and could reach 100%.Moreover,its germination time only need 7 days.The best culture medium for multiplication of cluster shoots is 1/2 MS 4.0 mg/L 6-BA 0.2 mg/L NAA 100 g/L CM(coconut milk),on which the multiplication rate was 4.41.The medium with 1/2 MS 0.2 mg/L NAA was favorable to the growth of roots and the rate of rootage was 90%.
The Chromosome Numbers of 12 Species in Orchidaceae from China
十二种国产兰科植物的染色体数目

Yang Di-Qing,Zhu Xie-Fu,
杨涤清
,朱燮桴

中国科学院研究生院学报 , 1984,
Abstract: The present paper reports the chromosome numbers of 12 species in Or- chidaceae from China. The results are as follows: Bletilla striata (Thunb.) Rchb. f. 2n= 32, Calanthe discolor Lindl. 2n=40, Calanthe hamata Hand. -Mazz. 2n=40, Cephalanthera erecta (Thunb.) Bl. 2n=34, Cephalanthera falcata (Thunb.) B1. 2n=34, Changnienia amoena Chien 2n=46, Cremastra appendiculata (D. Don) Makino 2n = 42, Dendrobium moniliforme (L.) Sw. 2n=38, Gastrodia elata Bl. n=15, 18, Liparis dunnii Rolfe 2n= 20, Platanthera minor (Miq.) Rchb. f. 2n=42, Pleione bulbocoidioides (Franch.) Rolfe 2n=40.
Melanogenesis and Antityrosinase Activity of Selected South African Plants
Manyatja Brenda Mapunya,Roumiana Vassileva Nikolova,Namrita Lall
Evidence-Based Complementary and Alternative Medicine , 2012, DOI: 10.1155/2012/374017
Abstract: Melanin is the pigment that is responsible for the colour of eyes, hair, and skin in humans. Tyrosinase is known to be the key enzyme in melanin biosynthesis. Overactivity of this enzyme leads to dermatological disorders such as age spots, melanoma and sites of actinic damage. Ten plants belonging to four families (Asphodelaceae, Anacardiaceae, Oleaceae, and Rutaceae) were investigated for their effect on tyrosinase using both L-tyrosine and L-DOPA as substrates. Ethanol leaf extracts (500 μg/mL) of Aloe ferox, Aloe aculeata, Aloe pretoriensis, and Aloe sessiliflora showed 60%, 31%, 17%, and 13% inhibition of tyrosinase activity respectively, when L-tyrosine was used as a substrate. Harpephyllum caffrum (leaves) at a concentration of 500 μg/mL had an inhibitory effect of 70% on tyrosinase when L-DOPA was used as a substrate. The IC50 of Harpephyllum caffrum (leaves and bark) were found to be 51±0.002 and 40±0.035 μg/mL, respectively. Following the results obtained from the tyrosinase assay, extracts from Harpephyllum caffrum were selected for further testing on their effect on melanin production and their cytotoxicity on melanocytes in vitro. The IC50 of both extracts was found to be 6.25 μg/mL for melanocyte cells. Bark extract of Harpephyllum caffrum showed 26% reduction in melanin content of melanocyte cells at a concentration of 6.25 μg/mL. The leaf extract of this plant showed some toxicity on melanocyte cells. Therefore, the bark extract of Harpephyllum caffrum could be considered as an antityrosinase agent for dermatological disorders such as age spots and melasoma.
白及种子直播繁育新方法
The new direct seeding and breeding method of Bletilla striata
 [PDF]

牛俊峰,王喆之
- , 2016, DOI: 1672-4291(2016)04-0083-04doi:10.15983/j.cnki.jsnu.2016.04.346
Abstract: 提出一种白及种子直播繁殖的新方法,该方法由种子活力测定、苗床整理、配制育苗基质、种子的处理、播种及壮苗步骤组成。结果表明:选择树皮粉、腐殖质、营养土、鸡粪和草炭土按体积比为15∶20∶8∶1∶5配成的育苗基质,控制空气温度20~35 ℃、湿度为60%~80%,在种子萌发不同阶段定期喷洒不同的营养液,种子萌发率可由自然条件下5%提升至69.7%±3.13%;播种180 d假鳞茎直径可达1~1.5 cm。本方法简单易行,出苗速度快,且克服了因种子细小、没有胚乳、在自然条件下极难萌发的困境,适合秦巴山区及以南的区域大规模种植白及
Antioxidant and Antityrosinase Activity of Flemingia macrophylla and Glycine tomentella Roots
Bor-Sen Wang,Lih-Jeng Juang,Jeng-Jer Yang,Li-Ying Chen,Huo-Mu Tai,Ming-Hsing Huang
Evidence-Based Complementary and Alternative Medicine , 2012, DOI: 10.1155/2012/431081
Abstract: The antioxidant and antityrosinase activities of the water extract of Flemingia macrophylla root (WEFM) were investigated. The results showed that WEFM exhibited radical scavenging and reducing activities, as well as ferrous ion chelating property. In addition, WEFM also protected phospholipids against oxidation, indicating that WEFM could protect biomolecules from oxidative damage. Meanwhile, in the range of 50–100 μg/mL, the tyrosinase inhibitory activity of WEFM increased with an increase in sample concentration and was superior to that of the water extract of Glycine tomentella root (WEGT). A high performance liquid chromatography analysis was used to determine the phenolic components, revealing that daidzin, daidzein, genistin, and genistein were present in WEFM and WEGT. Acting as an antioxidant and a tyrosinase inhibitor, these bioactive constituents could contribute to the protective effects of WEFM. Overall, the results showed that WEFM might serve as a natural antioxidant and tyrosinase inhibitor.
Antioxidant and Antityrosinase Activities of Various Extracts from the Fruiting Bodies of Lentinus lepideus  [PDF]
Ki Nam Yoon,Nuhu Alam,Kyung Rim Lee,Pyung Gyun Shin,Jong Chun Cheong,Young Bok Yoo,Tae Soo Lee
Molecules , 2011, DOI: 10.3390/molecules16032334
Abstract: Lentinus lepideus is an edible mushroom currently available in Korea. The acetone, methanol and hot water extracts were prepared and assayed for their antioxidant and antityrosinase inhibitory activities. The hot water extract showed the strongest β-carotene-linoleic acid inhibition compared to the other extracts. At 8 mg/mL, the methanolic extract showed a high reducing power of 1.21. The acetone and methanol extracts were more effective in scavenging DPPH radicals than the hot water extract. The strongest chelating effect was obtained from the methanolic extract. Xanthine oxidase and tyrosinase inhibitory activities of the acetonic, methanol and hot water extracts increased with increasing concentration. Gallic acid, chlorogenic acid, vanillin, naringin, naringenin, formononetin, and biochanin-A were detected in the acetonitrile and hydrochloric acid (5:1) solvent extract. This study suggests that fruiting bodies of L. lepideus can potentially be used as a readily accessible source of natural antioxidants.
The occurrence of Glyceria striata (Lam.) Hitchc. in Europe and the new localities of the species in Poland
Bartosz Piwowarski,Wac?aw Bartoszek
Acta Societatis Botanicorum Poloniae , 2012, DOI: 10.5586/asbp.2012.004
Abstract: Glyceria striata (Lam.) Hitchc. is a North American species that has been recorded in most, semi-natural habitats in Europe, e.g. in meadows, bog springs, margins of water bodies. It is circumscribed within two taxa of lower rank: G. striata subsp. striata and G. striata subsp. stricta. Only G. striata subsp. stricta has been reported from Europe. This paper gives a list of the European locali- ties of the species (48) and describes two newly discovered localities in Poland (the Wy yna Ma opolska upland and the Western Carpathian Mts.). The distribution of G. striata in Europe is mapped and potential migration routes of the species are discussed.
白及原生质体的分离与纯化
A Protocol for the Isolation and Purification of Protoplast from Bletilla striata Leaves
 [PDF]

徐德林, 张林, 储士润, 韦欣, 钱刚, 郑明辉
XU De-Lin
, ZHANG Lin, CHU Shi-Run, WEI Xin, QIAN Gang, ZHENG Ming-Hui

植物研究 , 2016, DOI: 10.7525/j.issn.1673-5102.2016.05.023
Abstract: 为建立起白及原生质体分离纯化的技术体系,以白及组培苗叶片为材料,经不同方式预处理后,用不同浓度的纤维素酶、果胶酶、离析酶和甘露醇组合进行酶解,将释放出来的原生质体用过滤和离心的方法进行纯化,最后用荧光素双醋酸酯(FDA)法对纯化的原生质体进行活力率测定,以期系统建立起酶解法从叶片中分离纯化出白及原生质体的技术流程。结果发现在低温黑暗+0.75 mol·L-1甘露醇条件下对叶片进行预处理、酶液组合为1.5%纤维素酶Cellulase R-10+0.4%果胶酶Pectolyase Y-23+0.5%离析酶Macerozyme R-10+0.75 mol·L-1甘露醇、酶解液pH值保持在5.8、摇床转速120 r·min-1、酶解4 h时,得到的原生质体产量最大,达4.72×106个·g-1,活力率也达90.4%。本研究构建了用白及叶片分离和纯化原生质体的技术流程,为白及遗传资源的拓展和遗传改良奠定了一定的物质和技术基础。
Two sympatric spesies of the Mamuya Striata Complex (Sauria: Scincidae) in the Southern Kalahari  [cached]
Donald G. Broadley
Koedoe : African Protected Area Conservation and Science , 1969, DOI: 10.4102/koedoe.v12i1.743
Abstract: Two sympatric spesies of the Mamuya Striata Complex (Sauria: Scincidae) in the Southern Kalahari
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