齿瓣石斛组织培养技术研究

以齿瓣石斛蒴果为外植体进行胚培养的试验表明,初始萌发培养基为1/2MS;原球茎萌发培养基为3/4MS＋10%马铃薯汁＋5%香蕉汁＋6-BA0.2mg·L^-1＋NAA0.05mg·L^-1＋0.05%AC;继代增殖培养基为MS＋10%马铃薯汁＋10%香蕉汁＋6-BA0.5mg.L^-1＋NAA0.2mg.L^-1＋0.1%AC;壮苗生根培养基为1/2MS＋10%香蕉汁＋5%马铃薯汁＋6-BA0.2mg·L^-1＋NAA1.0mg·L^-1＋0.1%AC,生根诱导率达100%,成活率达90%以上。     

铁皮石斛茎段丛生芽诱导研究

通过对铁皮石斛组培过程的外植体消毒方法,以及不同培养基、培养基添加物的筛选试验,结果表明：多种消毒剂配合使用并进行二次消毒的效果最好;基础培养基以1/2MS较好;1/2 MS＋5.0mg/L NAA＋2.0mg/L 6-BA是最适合丛芽分化的诱导培养基;在培养基中添加香蕉10%＋洋芋10%生根多,瓶苗长势好。     

铁皮石斛组培快繁及移栽技术研究

以红杆铁皮石斛种子为外植体,进行组织培养快繁及移栽技术研究。采用对比试验研究不同培养基、激素浓度配比、基本培养基对铁皮石斛原球茎增殖、分化和生根壮苗的影响,并研究驯化时间与移栽基质对铁皮石斛移栽的影响。结果表明,MS+10％马铃薯泥+20％香蕉泥＋20 g/L蔗糖+6 g/L琼脂最适合铁皮石斛原球茎增殖;MS+0.5 mg/L NAA+3.0 mg/L BA+20 g/L蔗糖+6 g/L琼脂+200 ml/L椰汁最适合原球茎分化;1/2MS+0.5 mg/L NAA+15％香蕉泥+20 g/L蔗糖+6 g/L琼脂最适合铁皮石斛壮苗生根;驯化28 d的铁皮石斛移栽成活率最高,达96%;以松树皮∶椰糠∶石头=1∶1∶1为栽培基质,对其苗长势最佳。     

铁皮石斛高效再生体系研究与应用

以原球茎为实验材料,对影响铁皮石斛再生体系的主要影响因素进行试验,建立铁皮石斛在生产中的高效再生体系。试验结果表明,在基本培养基MS、Fonnesbech和N6中,最适合的基本培养基为MS;原球茎最佳增殖培养基为MS＋6-BA0.75 mg/L＋NAA0.2 mg/L＋4.0% 白糖,接种35 d后原球茎增殖倍数为4.19;最佳分化培养基为MS＋6-BA0.3 mg/L＋3.0%白糖,分化率为74%。分化出的丛芽在生根培养基MS＋AC0.05%＋白糖3.0% 中,28 d生根率达到87%。     

铁皮石斛杂交种组织培养技术试验

以铁皮石斛杂交种子为外植体的组织培养技术试验结果：铁皮石斛杂交种原球茎最佳诱导培养基为3/4Ma＋5%椰子汁;增殖分化培养基为3/4Ma＋6-BA 0.2 mg·L-1＋NAA 0.1 mg·L-1＋10%马铃薯泥＋2%香蕉泥;壮苗生根培养基为3/4Ma＋6-BA 0.2 mg·L-1＋NAA 1.0 mg·L-1＋8%马铃薯泥＋5%香蕉泥,生根率可达100%,移栽成活率在97%以上。     

鼓槌石斛组培快繁技术体系研究

以鼓槌石斛八成熟蒴果为外植体,通过对其种子无菌萌发培养、原球茎继代增殖及生根壮苗培养基的筛选,建立鼓槌石斛的组培快繁技术体系。结果表明：1/2 MS＋1.0 mg/L NAA＋8.0%土豆泥＋0.10%活性炭培养基效果较理想,种子萌发率较高,发芽快;最适增殖培养基为3/4 MS+3.0 mg/L 6-BA＋8%香蕉泥,增殖系数可达7.23;最佳生根培养基为3/4 MS＋1.0 mg/L NAA＋0.5 mg/L CA＋8%香蕉泥,平均根数量达7.49条。炼苗移栽到松树皮作为栽培基质的苗床上,1个月以后,成活率均达80%。     

不同有机添加物对叶底红生根壮苗的影响

以叶底红试管苗为材料,以1/2MS+IBA0.5 mg/L+蔗糖30 g/L+活性炭1 g/L为基础培养基,对根系、颜色、株高及最大叶的长和宽等不同形态指标进行加权分析,研究香蕉、椰汁、马铃薯、蛋白胨等4种培养基添加物对试管苗生根壮苗的影响。结果表明:4种有机添加物对生根壮苗的促进作用由大到小依次为椰汁、香蕉、蛋白胨、马铃薯。     

闽西宁化2个铁皮石斛品系离体培养条件的优化

[目的]优化闽西宁化2个铁皮石斛品系的离体培养条件。[方法]以闽西宁化红杆和青杆2个铁皮石斛试管苗为材料,设计了8组培养基对2个铁皮石斛品系离体培养条件进行优化。[结果]MS+6-BA 0.5 mg/L+NAA 0.5 mg/L培养基有利于红杆铁皮石斛和青杆铁皮石斛丛生芽增殖;MS+KT 0.5 mg/L+NAA 0.5 mg/L培养基有利于红杆铁皮石斛、青杆铁皮石斛壮苗生长,壮苗培养基适当添加香蕉泥有利于植株增高。[结论]2个铁皮石斛品系间的丛生芽增殖和根系生长能力存在较大差异,红杆铁皮石斛的丛生芽增殖能力弱于青杆铁皮石斛;红杆铁皮石斛的根系长度和分蘖数都低于青杆铁皮石斛,一级根系数高于青杆铁皮石斛。     

2种多胺对铁皮石斛瓶内开花的影响

以铁皮石斛无根组培苗为试验材料,研究不同浓度的外源腐胺（Put）和精胺（Spm）对铁皮石斛瓶内开花的影响。结果表明：培养基中添加适量的Put和Spm可提高开花率。当Put浓度为0.4 mg/L时,铁皮石斛瓶内开花率最高,为30.47%;Spm浓度为0.2 mg/L时,铁皮石斛瓶内开花率最高,为22.26%;Put浓度为0.2 mg/L时,铁皮石斛始花期最短,为83.33 d,观赏期最长,为43.33 d。Put浓度为0.4 mg/L时,植株可溶性糖和可溶性蛋白含量最高;对照处理下植株全N含量达最高;Spm浓度为0.6 mg/L时,植株C/N比达最大。Put浓度为0.4 mg/L时,有利于铁皮石斛组培苗碳氮化合物的积累,可提高铁皮石斛的开花率;Put浓度为0.2 mg/L时,能使花期提前,延长观赏期。Spm浓度为0.4 mg/L时,有利于铁皮石斛组培苗株高增长和生根,促进铁皮石斛组培苗的营养生长。     

黑甘薯脱毒快繁技术研究

以富含硒的日本黑薯的茎尖为材料进行脱毒快繁研究,结果表明剥取小于0.3 mm的甘薯茎尖进行组织培养产生愈伤的最适培养基是MS＋6-BA1.0 mg/L＋NAA0.1 mg/L;继代培养基为MS;生根培养基为1/2MS＋活性炭,填加活性炭的生根培养基能提高生根率。     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Extreme resistance to infection by potato virus X in genotypes of wild tuber-bearingSolanum species

Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X¹ (also called RX_act).     

Cyanobacteria Secondary Metabolites as Biotechnological Ingredients in Natural Anti-Aging Cosmetics: Potential to Overcome Hyperpigmentation,Loss of Skin Density and UV Radiation-Deleterious Effects

The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O₂^•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O₂^•− scavenging, (IC₅₀ = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC₂₅ = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC₅₀ = 863 µg/mL; elastase, IC₅₀ = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O₂^•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.     

Marine Pharmacology in 2009–2011: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis,and Antiviral Activities; Affecting the Immune and Nervous Systems,and other Miscellaneous Mechanisms of Action ?

The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.     

Recent Modifications of Chitosan for Adsorption Applications: A Critical and Systematic Review

Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).