Bioactivity guided isolation of antimicrobial compounds from Lythrum salicaria

Lythrum salicaria extracts showed activity against the phytopathogenic fungus Cladosporium cucumerinum and activity against the bacteria Staphylococcus aureus, Proteus mirabilis and Microccocus luteus. Bioautography on thin-layer chromatograms was used to isolate the two antifungal triterpenoids oleanolic and ursolic acid. The hexahydroxydiphenoyl ester vescalagin was isolated as active principle of the antibacterial activity. Furthermore, the flavon-C-glucosides vitexin, isovitexin, orientin and isoorientin were isolated.     

红叶石楠愈伤组织的诱导

研究了外植体类型、植物生长调节剂组合、光暗处理对红叶石楠品种"红罗宾"愈伤组织诱导的影响,结果表明:在NAA和BA不同配比的MS培养基上,均能从叶柄、叶片和节间诱导出愈伤组织;综合愈伤组织诱导率和愈伤组织松脆性,以叶柄和叶片在添加NAA 0.1 mg/L和BA 0.5 mg/L的MS培养基上诱导产生的愈伤组织最佳.叶柄和叶片诱导的愈伤组织能维持松脆状;节间发生的愈伤组织易转变为水渍状.暗培养可以抑制色素的产生从而有利于获得松脆的愈伤组织;春季愈伤组织的诱导率明显高于秋季.     

Effects of plant growth regulators,carbon sources and pH values on callus induction in Aquilaria malaccensis leaf explants and characteristics of the resultant calli

The endangered tropical tree, Aquilaria malaccensis, produces agarwood for use in fragrance and medicines. Efforts are currently underway to produce valuable agarwood compoundsn tissue culture. The purpose of this study was to develop an optimal growth medium, specifically, the best hormone combination for callus suspension culture. Using nursery-grown A. malaccensis, sterilized leaf explants were first incubated on basic Murashige and Skoog(MS) gel medium containing 15g/L sucrose and at pH 5.7. Different auxin types including 1-naphthaleneacetic acid(NAA), 2,4-dichlorophenoxyacetic acid(2,4-D), and indole-3-butyric acid(IBA), were tested at various concentrations(0.55, 1.1 and 1.65 μM) using the basic medium. Leaf explants were incubated for 30 days in the dark. Callus induced by 1.1 μM NAA had the highest biomass dry weight(DW) of 17.3 mg; however the callus was of a compact type. This auxin concentration was then combined with either 6-benzylaminopurine(BAP) or kinetin at 0.55, 1.1, 2.2 or 3.3 μM to induce growth of friable callus. The 1.1μM NAA + 2.2μM BAP combination produced friable callus with the highest biomass(93.3mg DW). When testing the different carbon sources and pHs, sucrose at 15g/L and pH at 5.7 yielded highest biomasses at 87.7mg and 83 mg DW, respectively. Microscopic observations revealed the arrangement of the friable cells as loosely packed with relatively large cells, while for the compact callus, the cells were small and densely packed. We concluded that MS medium containing 15 g/L sucrose, 1.1 μM NAA + 2.2 μM BAP hormone combination, and a pH of 5.7 was highly effective for inducing friable callus from leaf explants of A. malaccensis for the purpose of establishing cell suspension culture.     

Nitraria sibirica cell suspension culture:establishment,characterization and application

Nitraria sibirica Pall.is a shrub that grows in saline-alkali soil and has traditional medicinal value and potential commercial value.The objectives of this study include induction and multiplication of callus,establishment of a suspension cell line,and isolation of protoplasts from cell suspensions.Murashige and Skoog(MS) medium was used for callus induction from mature seeds of N.sibirica.Seed-derived calluses were further multiplied on MS medium augmented with 0.5 mgL~(-1) 6-benzylaminopurine(6-BA) and 1.0 mgL~(-1) 2,4-dichlorophenoxy(2,4-D) acetic acid.Suspension cultures of N.sibirica were initiated by transferring friable calli to the same liquid multiplication medium.Characterization of the suspension culture was assessed based on fresh mass,dry mass,cell viability and p H value of the culture.A typical growth curve was observed after inoculating 1.5 g of callus in 40 mL liquid medium,including a lag phase,an exponential growth phase,a stationary phase,and a negative acceleration phase.The effect of factors such as pre-plasmolysis,enzyme combination,enzymolysis time and mannitol concentration,on the isolation of cell-derived protoplasts were evaluated to determine the usefulness of suspension cultures.The maximum yield(9.79 9 106 cells/g) and highest viability(79.97%) of protoplast were reached when approximately 1 g of cell suspension(cultured for 6 days) was inoculated for 12 h in cell and protoplast washing solution made of 0.8 molL~(-1) mannitol mixture solution,cellulose onozuka R-10 2%(w/v),hemicellulose 0.2%,macerozyme R-10 1%,and pectolyase Y-23 0.5%.Protoplast yield was significantly influenced by pre-plasmolysis and cellulose onozuka R-10(P0.05).     

大果西番莲的扦插育苗

介绍了大果西番莲的生长习性和扦插繁殖时的季节、扦插基质、插穗的选择、扦插方法以及扦插后的管理。       

Isoflavonoid production by callus cultures of Maackia amurensis

Callus cultures were established from the different parts of Maackia amurensis plants and analyzed for isoflavonoids. The isoflavones daidzein, retuzin, genistein and formononetin and the pterocarpans maakiain and medicarpin were found to be produced by these cultures. The content of isoflavones and pterocarpans was essentially the same in cultures derived from leaf petioles, inflorescences and apical meristems of the plant. The maximal yield of isoflavones and pterocarpans in calluses was 20.8 mg/g cell dry wt., approximately four times higher than the content of the heartwood of M. amurensis plants. Unlike wild-growing plants, none of the cell cultures had the ability to accumulate stilbenes.     

Cytotoxic activity of extracts from Linum cell cultures

Callus and suspension cultures of Linum narbonense and Linum leonii were developed to study the production of lignans and their cytotoxic activity. Justicidin B was determined to be the main lignan. The maximal yield of justicidin B up to 2.22 mg/g of the cell dry weight was detected in the callus cultures of L. leonii, followed by the callus cultures of L. narbonense (1.57 mg/g dwt). The cytotoxicity of the obtained extracts was measured using the MTT-dye assay. L. narbonense and L. leonii both showed cytotoxic activity.     

Ecophysiological aspects of in vitro biotechnological studies using somatic embryogenesis of callus tissue toward protecting forest ecosystems

This review on current biotechnological methods in forestry for in vitro tissue cultures to define the effect of stress conditions on trees,concentrates on somatic embryogenesis.Callus tissue,the key product of somatic embryogenesis,grows over a tree wound under ex vitro conditions.Callus tissue can be used in research in areas such as pathogenic susceptibility at the embryonic level,effect of heavy metals,influence of low temperatures(cryopreservation),production of secondary metabolites and transformation of plants.Callus of arborescent plants can be induced in vitro by fungal elicitors to produce secondary metabolites for pharmaceutical and cosmetic industries and are strongly repellant to herbivores and can thus act to protect forests.Analyses of dual cultures demonstrated that callus tissue exposed to a pathogenic fungus responds by synthesizing low-molecular-mass proteins belonging to an immune protein class.Cryopreservation of embryonic callus tissue also has broad applications,e.g.,for valuable plant genotypes in gene banks.Without strategies to protect forests against stressfactors,forest ecosystems will degrade to the detriment of all life,including humans.In vitro biotechnological research using callus tissue contributes to progress in forestry and the disciplines of ecology,physiology,phytopathology,culture and selection of plants.     

Anthraquinone production by callus cultures of Rubia cordifolia

Munjistin and purpurin were identified as the major components of anthraquinone pigments produced by callus cultures of R. cordifolia. Anthraquinone content in calluses was 0.62–1.22% (by dry wt.) depending on the source of explants. Selection of coloured aggregates yielded a cell line with twofold increase in anthraquinone production.     

Regeneration, in vitro glycoalkaloids production and evaluation of bioactivity of callus methanolic extract of Solanum tuberosum L.

Callus and differentiated shoots initiated from Solanum tuberosum L. on MS media containing BA, IAA, and Kin. Glycoalkaloids are produced in callus and shoots in concentrations higher than original tubers using HPLC. Callus methanolic extract had promising anticancer activity with low IC₅₀ values against human carcinoma cell lines of breast, lymphoplastic leukemia, larynx, liver, cervix, colon, and brain, IC₅₀ (µg/mL) were 2.7, 3.7, 6, 6.7, 10, 13.6, and 22.3 respectively. Antioxidant capacity of the extract (76.4%) performed using ESR. Preliminary screening showed that the extract exhibited in vitro virucidal activity against Herpes simplex. The extract possessed in vitro schistomicidal and fasciolicidal activity.     

地涌金莲组织培养中的褐化抑制

地涌金莲组织培养中的褐化问题一直是其优良品种选育及规模化生产的技术瓶颈。为解决这一问题,以地涌金莲未成熟雄花为试材,研究了外植体消毒方式、植物生长调节剂种类及配比和不同抗褐化剂对愈伤组织褐化的影响。结果表明,未经消毒的外植体其污染率为0%,且褐化率和褐化指数均显著低于消毒后的外植体;6-BA在地涌金莲愈伤组织诱导中起主要作用,浓度为2 mg·L-1、3 mg·L-1时有利于愈伤组织的诱导,能显著降低褐化指数;添加柠檬酸+抗坏血酸(VC)混合液、表面添加VC均对地涌金莲褐化未起到明显抑制作用,姜汁和阿魏酸对抑制愈伤组织褐化有较好的效果,48.5 mg·L-1的阿魏酸能显著降低愈伤组织的褐化,使愈伤组织分化率达17.9%,较对照的2.9%提高了15%。     

利用悬浮培养和培养基选择改善火炬松的体细胞胚胎发生和植株再生(英文)

三个基固型的火炬松成熟合子胚被培养在附加 8mg·L-12 ,4 D ,4mg·L-1BA ,4mg·L-1KT ,5 0 0mg·L-1水解酪蛋白和 5 0 0mg·L-1谷氨酰胺的愈伤组织诱导培养基上诱导愈伤组织 .来自于子叶、胚轴和胚根的愈伤组织在附加 1 6mg·L-12 ,4 D ,0 8mg·L-1BA和 0 8mg·L-1KT的愈伤组织增殖培养基上培养 9周后 ,可获得 16 9%的胚性愈伤组织 .通过建立胚性细胞悬浮系和研究ABA、PEG和活性炭对体细胞胚成熟的促进作用 ,优化的体细胞胚胎发生体系被建立 .71棵再生小苗被用于移栽试验 ,2 3棵小苗在田间移栽成活     

榉树叶器官再生植株技术

以榉树（Zelkova schneideriana）叶片为外植体,先诱导愈伤组织的产生,再诱导愈伤组织分化出芽,研究榉树叶器官再生植株技术,结果表明：榉树叶片诱导出愈伤组织很容易,幼嫩叶片的诱导率可达到90％以上,而由愈伤组织诱导芽分化则相对较难,仅有10％左右的诱导率,老叶片诱导的愈伤无法再分化出芽。     

<Emphasis Type="Italic">Nitraria sibirica</Emphasis> cell suspension culture: establishment,characterization and application

Nitraria sibirica Pall. is a shrub that grows in saline-alkali soil and has traditional medicinal value and potential commercial value. The objectives of this study include induction and multiplication of callus, establishment of a suspension cell line, and isolation of protoplasts from cell suspensions. Murashige and Skoog (MS) medium was used for callus induction from mature seeds of N. sibirica. Seed-derived calluses were further multiplied on MS medium augmented with 0.5 mg L^?1 6-benzylaminopurine (6-BA) and 1.0 mg L^?1 2,4-dichlorophenoxy (2,4-D) acetic acid. Suspension cultures of N. sibirica were initiated by transferring friable calli to the same liquid multiplication medium. Characterization of the suspension culture was assessed based on fresh mass, dry mass, cell viability and pH value of the culture. A typical growth curve was observed after inoculating 1.5 g of callus in 40 mL liquid medium, including a lag phase, an exponential growth phase, a stationary phase, and a negative acceleration phase. The effect of factors such as pre-plasmolysis, enzyme combination, enzymolysis time and mannitol concentration, on the isolation of cell-derived protoplasts were evaluated to determine the usefulness of suspension cultures. The maximum yield (9.79 × 10⁶ cells/g) and highest viability (79.97%) of protoplast were reached when approximately 1 g of cell suspension (cultured for 6 days) was inoculated for 12 h in cell and protoplast washing solution made of 0.8 mol L^?1 mannitol mixture solution, cellulose onozuka R-10 2% (w/v), hemicellulose 0.2%, macerozyme R-10 1%, and pectolyase Y-23 0.5%. Protoplast yield was significantly influenced by pre-plasmolysis and cellulose onozuka R-10 (P < 0.05).     

Different growth sensitivity to enhanced UV-B radiation between male and female Populus cathayana

We investigated sex-related morphological and physiological responses to enhanced UV-B radiation in the dioecious species Populus cathayana Rehd. Cuttings were subjected to two UV-B radiation regimes: ambient (4.5 kJ m?2 day?1) and enhanced (12.5 kJ m?2 day?1) biologically effective UV-B radiation for one growing season. Enhanced UV-B radiation was found to significantly decrease the shoot height and basal diameter and to reduce the leaf area, dry matter accumulation, net photosynthesis rate (P(n)), chlorophyll a/b ratio (Chl a/b) and anthocyanin content. Enhanced UV-B radiation also increased chlorophyll pigment, leaf nitrogen, malondialdehyde and abscisic acid (ABA) content, superoxide dismutase and peroxidase activities and UV-B-absorbing compounds. No significant effects of enhanced UV-B radiation were found on biomass allocation, gas exchange (except for P(n)), photochemical efficiency of photosystem II or water use efficiency. Moreover, different sensitivity to enhanced UV-B radiation between males and females was detected. Under enhanced UV-B radiation, males exhibited significantly higher basal diameter and leaf nitrogen, and lower Chl a/b, ABA content, UV-B-absorbing compounds, as well as less decrement of leaf area and dry matter accumulation than did females. However, no significant sexual differences in these traits were found under ambient UV-B radiation. Our results suggest that males may possess a greater UV-B resistance than do females, with males having a more efficient antioxidant system and higher anthocyanin content to alleviate UV-B penetration stress than females.     

杜仲愈伤组织培养过程中胶含量的动态变化

培养杜仲愈伤组织并测定其含胶量,结果发现,杜仲胶的合成与愈伤组织的生长周期有一定的相关性。在继代培养中,随着继代次数的增加,含胶量呈增加趋势。外植体上愈伤组织一旦形成就有杜仲胶的积累,杜仲胶含量在S5~S8代出现一个高峰值,S8代愈伤组织的含胶量已经达到原植株的94.38%,S9代后又迅速下降。     

Growth and physiological responses to supplemental UV-B radiation of two contrasting poplar species

We compared the growth and physiological responses of cuttings of Populus kangdingensis C. Wang et Tung and P. cathayana Rehder originating from altitudes of 3500 m and 1500 m, respectively, when exposed to three ultraviolet-B (UV-B) radiation regimes: zero UV-B, ambient (4.5 kJ m(-2) day(-1)) and twice-ambient (9 kJ m(-2) day(-1)) biologically effective UV-B radiation for one growing season, to determine if Populus trees that are adapted to contrasting UV-B habitats exhibit different tolerances to enhanced UV-B radiation. Compared with cuttings grown without UV-B radiation, twice-ambient UV-B radiation significantly decreased total biomass, total leaf area and internode length in both species, whereas root/shoot ratio, leaf number, amount of photosynthetic pigments and ascorbate peroxidase activity were unaffected. Differences in responses were also observed between the study species. Cutting height increment, total biomass, total leaf area, free proline concentration and membrane damage assessed by electrolyte leakage were significantly more affected by the twice-ambient UV-B radiation in P. cathayana than in P. kangdingensis. However, specific leaf mass, amount of UV-B absorbing compounds and superoxide dismutase and guaiacol peroxidase activities increased more with increasing UV-B radiation in P. kangdingensis than in P. cathayana, perhaps reflecting important characteristics of species with low to moderate tolerance to UV-B radiation. Overall, the results indicated that P. kangdingensis, which originates from altitudes of 3500 m, has greater tolerance to enhanced UV-B radiation than P. cathayana originating from altitudes of 1500 m.     

Micropropagation and tissue culture of Eucalyptus-a review

Micropropagation has the potential to provide very high multiplication rates of selected tree genotypes, with resulting short-term silvicultural gains. Aseptic cultures have been established from seeds, seedlings, shoots, flowers and lignotubers. Callus cultures have been established from a wide range of tissue sources for at least 30 species of Eucalyptus. Plant regeneration from callus was successful for 12 of these species. Micropropagation through axillary proliferation, or adventitious shoot proliferation on nodal explants, or both, has been successful. An agar-based medium of Murashige and Skoog with a low auxin/cytokinin ratio is most commonly used for shoot multiplication. Vitrification and shoot senescence remain problems. Gibberellic acid was added in some media to stimulate shoot elongation. Various media are used for in vitro root initiation. Suspension and protoplast cultures have been achieved and plants have been regenerated from protoplasts. In vitro techniques are presently being applied to Eucalyptus to achieve genetic transformations.     

Responses to ultraviolet-B radiation by purely symbiotic and NO3-fed nodulated tree and shrub legumes indigenous to southern Africa

Purely symbiotic and NO3-fed nodulated seedlings of Virgilia oroboides (Bergius) T.M. Salter, Cyclopia maculata (L.) Vent and Podalyria calyptrata Willd. were exposed to biologically effective ultraviolet-B radiation (UV-B) to assess the effects of above- and below-ambient UV-B on growth, symbiotic function and metabolite concentrations. Seedlings were grown outdoors either on tables under ambient or 34 or 66% above-ambient UV-B conditions (UV-B100 control, UV-B134 and UV-B166, respectively), or in chambers providing below-ambient (22% of ambient) UV-B (UV-B22) along with a UV-A control and a photosynthetically active radiation (PAR) control. Exposure of seedlings to UV-B166 radiation reduced (P < or = 0.05) leaf and stem dry mass by 34 and 39%, respectively, in C. maculata, and reduced leaf nitrogen concentration (%N) by 12% in V. oroboides. Nodule %N in C. maculata and stem %N in P. calyptrata also decreased (P < or = 0.05) in response to UV-B22 radiation compared with the UV-A control, but not compared with the PAR control. Concentrations of flavonoids, soluble sugars and starch were unaltered by the UV-B treatments. Application of 1 mM NO3 to UV-B166-treated seedlings increased whole-plant dry mass of V. oroboides and P. calyptrata by 47 and 52%, respectively. Dry mass of organs, nodule %N and total N concentration of these species also increased with NO3 application. However, NO3 supply decreased (P < or = 0.05) nodule dry mass, stem %N and leaf %N as well as root and leaf anthocyanin concentrations in C. maculata. In terms of UV-B x N interactions, dry mass of stems, roots, nodules and total biomass of NO3-fed C. maculata seedlings were reduced, and nodule %N, total N and leaf anthocyanins were depressed by the UV-B134 and UV-B166 treatments relative to UV-B100-treated seedlings. Although we found that above-ambient UV-B had no effects on growth and symbiotic function of V. oroboides and P. calyptrata seedlings, feeding NO3 to these species increased (P < or = 0.05) seedling growth. In contrast, purely symbiotic C. maculata seedlings were sensitive to the UV-B166 radiation treatment, and adding NO3 further increased their sensitivity to both the UV-B134 and UV-B166 treatments.     

草地早熟禾耐盐愈伤组织筛选的适宜NaCl浓度和继代次数研究

草地早熟禾(Poa pratensis L.)是禾本科早熟禾属多年生草本植物,是我国北方地区应用最广泛的冷季型草坪草.近年来,由于土壤的盐化问题日益严重,培育耐盐的草地早熟禾品种显得尤为重要.体细胞无性系变异是来源于已经存在的细胞变异和培养过程中诱导的变异[1].变异的诱导与选择为提高植物的耐盐性提供了一条有效的途径.