A new carotenoid, 5,6-dihydrocrustaxanthin,from prawns and the distribution of yellow xanthophylls in shrimps

A new yellow carotenoid, named 5,6-dihydrocrustaxanthin (6), was isolated together with five yellow xanthophylls: isoastaxanthin (1), 5,6-dihydropenaeusxanthin (2), penaeusxanthin (3), tetrahydroxypirardixanthin (4), and crustaxanthin (5) from three species of prawns: Marsupenaeus japonicus, Litopenaeus vannamei, and Metapenaeus joyneri, belonging to Penaeidae. The structure of (6) was determined to be (3R,4S,5R,6R,3′R,4′S)-5,6-dihydro-β,β-carotene-3,4,3′,4′-tetrol by UV-VIS, MS, ¹H NMR, and CD spectral data. Distributions of yellow xanthophylls (1–6) in ten species of shrimps were investigated from a chemo-systematic point of view. Yellow xanthophylls (1–6) were present in only three species of prawns described above, among the ten species of shrimps investigated. Instead of 1–6, luteins and tunxanthins, having the 3-hydroxy-ε-end group, were present in other species of shrimps belonging to Penaeidae, Pandalidae, and Palaemonidae.     

珍稀濒危植物金丝李种子脱水耐性和贮藏特性

为测定不同脱水程度金丝李(Garcinia paucinervis)种子的萌发情况及其复水后的吸水率、脱水过程中抗性生理指标的变化以及不同贮藏方式下种子的萌发情况,该文研究了金丝李种子的脱水敏感性和储藏特性。结果表明:(1)金丝李种子初始含水量为45.29%,室内通风处放置35 d失水率即达45%。(2)种子失水率低于18%时,萌发率和复水后的吸水率变化不显著;失水率超过18%时,萌发率和复水后吸水率均显著下降,失水率为42%时萌发率为0。其种子的临界含水量为27.29%,半致死含水量为12.72%。(3)随着种子脱水程度的加深,相对电导率、可溶性糖及脯氨酸含量逐步上升;丙二醛含量在失水率低于24%时变化不大,高于24%时显著提高; SOD和POD的活性均呈波动性变化,失水率为18%时活性均最高。(4)室温干藏1个月和-1、-20℃下湿藏1个月的种子均不能萌发;水浸贮藏1个月的种子萌发率显著降低; 4℃湿藏1、3和6个月均显著延缓种子萌发,但对萌发率无显著影响。表明金丝李种子在失水率低于18%时,种子可通过抗性调节维持细胞的正常代谢,能忍受一定程度的脱水和低温;当失水率超过18%时,种子代谢失衡发生劣变直至死亡,属于低度的顽拗性种子。4℃湿沙藏(含水量7.5%)是短期贮藏其种子的较好方法。     

Importance of plant integrity in crop research,breeding, and production

Plant integrity looks like a “very easy and expanded topic,” but the reality is totally different. Thanks to the very high specialization of scientists, we are losing a holistic view of plants and are making mistakes in our research due to this drawback. It is necessary to sense a plant in their whole complexity—in both roots and shoot, as well as throughout their life cycles. Only such an integrated approach can allow us to reach correct interpretations of our experimental results.     

Potency of plant extracts against Penicillium species isolated from different seeds and fruits in Saudi Arabia

Antifungal activity of extracts of cinnamon (Cinnamomum zeylanicum), Cloves (Syzygium aromaticum), ginger (Zingiber officinale) and turmeric (Curcuma longa) were evaluated in vitro against 17 Penicillium spp. Seed disease and rotten fruit caused by these species cause considerable loss of quality for different agricultural products. Isolates of Penicillium spp. were screened for production of patulin an important serious mycotoxin. About 70.59% of Penicillium spp. produced this toxin in concentrations ranging from 4 to 31 ppb. The response of Penicillium spp.to plant extracts differed according to the plant extract and concentration. Cinnamon extract showed the greatest effect on P. asperosporum, P. aurintogriseum and P. brevicompactum, and cloves extract produced the greatest effect on P. chermesinum and P. duclauxii. Turmeric extract had less effect on P. duclauxii. Cloves extract was the most effective in reducing the growth of Penicillium spp. On the other hand, ginger extract with all concentrations used had less effect against most Penicillium spp in the laboratory. Plant extracts are promising as natural sources of environmentally friendly compounds in laboratory studies.     

Loss of chlorophylls, cessation of photosynthetic CO2 assimilation and respiration in the poikilochlorophyllous plant Xerophyta scabrida during desiccation

During a slow desiccation in photosynthetically fully active leaves of the poikilochlorophyllous desiccation-tolerant (PDT) monocotyledon Xerophyta scabrida (Pax) Th. Dur. et Schinz (Velloziaceae), thylakoid activity, CO₂ assimilation and respiration decline and chlorophylls and carotenoids are successively broken down. The initially slow rate of leaf water loss is related to the large reduction in leaf area which is reflected in the decrease of specific leaf area. Chlorophylls are broken down faster than carotenoids. The ratio of the variable chlorophyll fluorescence, an indicator of photosynthetic activity (Rfd690-values), shows that the functionality of thylakoids and chlorophylls is successively lost during desiccation. The decline in net CO₂ assimilation in desiccating leaves is largely caused by stomatal closure. The complete cessation of CO₂ assimilation, however, is due to the breakdown of chlorophylls and thylakoids. Respiration continued during desiccation and remained active far below -3.2 MPa leaf water potential. The differences during desiccation of the photosynthetic apparatus between poikilochlorophyllous and homoiochlorophyllous desiccation-tolerant plants are discussed.     

The effect of biochanin A on the chlorophylls and carotenoids content in the alga <Emphasis Type="Italic">Chlorella vulgaris</Emphasis> Beijerinck

The present study was undertaken to determine the influence of biochanin A, isoflavone characterised by estrogenic activity, upon the content of chlorophylls and carotenoids in the cells of green alga Chlorella vulgaris Beijerinck (Chlorophyceae). On the 6^th day of cultivation under the influence of 10⁻⁶ M biochanin A exerted the greatest biological activity and the most stimulating effect on the analysed parameters: growth of the alga expressed by the cells number and the content of photosynthetic pigments in them. The total content of carotenoids was stimulated on the 6^th day of experiment in the range of 197 % but during the 9^th day only in 179 % in comparision with the control group (100 %). At the same time content of carotenes increased to the level of 123 – 119 % and xanthophylls to 208 – 178 %. Among the carotenes, β-carotene was characterised with the 3.7 times higher content in regard to the content of α-carotene on the 6^th day of cultivation and during the 9^th day — the 5.7 times domination. The content of xanthophylls that contain two atoms of oxygene in molecule (oxygen — poor xanthophylls) was intensively stimulated in the range of 224 %. Moreover, the oxygen — rich xanthophylls content reached the value 179 % when compared to the control. The greatest stimulation of the content of chlorophylls and its isomers was observed during the 3^rd day of cultivation of Chlorella vulgaris when it rose up to 166 % and to 156 % on the 6^th day. The content of chlorophyll b and its isomers was stimulated in 181 % on the 6^th day of culture and 155 % during the 9^th day of algal culture. The evidence on the stimulating effect of biochanin A as the main representative of isoflavones on the growth and content photosynthetic pigments in eucaryotic alga C. vulgaris was demonstrated in these studies.     

Caloric content of plant species and its role in a Leymus chinensis steppe community of Inner Mongolia, China

The caloric contents of 42 species and their composition in a Leymus chinensis steppe community of Inner Mongolia, China were determined and analyzed based on the field experiment for 11 years. The caloric content (x ± SD) of aboveground parts of plant species varied from (13156 ± 1141) J·g^?1 (ash contained) to (18141 ± 527) J·g^?1. The average caloric content of all species was (16899 ± 840) J·g^?1 and the inter-specific CV (coefficient of variation) was 4.9%. Of all the species, Caragana microphylla had the highest caloric content (18142 J·g^?1). Grasses had a higher average caloric content ((17425 ± 291) J·g^?1) than forbs ((16734 ± 844)J·g^?1). When the herbaceous species were classified into subgroups according to life-form and growth-form, the order of average caloric contents, from high to low, was: tall grasses ((17717 ± 92) J·g^?1) > legume ((17228 ± 433) J·g^?1) > short grasses ((17250 ± 218) J·g^?1) > remaining forbs ((16784 ± 529) J·g^?1) > subshrubs ((16719 ± 69) J·g^?1) > annuals and biennials ((15911 ± 1759) J·g^?1). There was a positive correlation (P < 0.05) between the caloric contents of 42 species and their relative biomass in the community. When all species were classified into 3 groups according to their composition in the community, the average caloric contents, weighed by the species relative biomass, followed the order: dominant (17740 J·g^?1) > companion (17244 J·g^?1) > incidental (16653 J·g^?1). The plants with high caloric contents were more competitive, which allowed them to gain a dominant status, whereas the competitive abilities of plants with low caloric contents were generally weak. The latter made up the companion or incidental species in a steppe community.     

Interconversions of Chlorophylls a and b Synthesized from Exogenous Chlorophyllides a and b in Etiolated and Post-Etiolated Rye Seedlings

A comparative study of reciprocal conversions of chlorophylls a and b (Chl aand Chl b) in etiolated and post-etiolated rye seedlings (Secale cereale L.) was performed. The production of these pigments was initiated by infiltration of exogenous chlorophyllides a and b (Chlide a and b). It was shown that Chlide b, when infiltrated into etiolated rye seedlings, was esterified, producing Chl b. A major portion of Chl b (more than 80%) was transformed into Chl aduring long-term seedling dark exposure. The high rate of Chl b conversion into Chl a in the pool of pigments of exogenous origin was also observed during the lag-phase when there was no chlorophyll formation from endogenous precursors. The infiltration of Chlide a resulted in Chl a formation. The efficiency of its conversion into Chl b was low (about 1%) in the etiolated seedlings but increased during their greening. In the post-etiolated seedlings infiltrated with Chlide b, which were preliminary illuminated for 6–12 h, the Chl /Chl a ratio was almost similar in the pools of pigments synthesized from both exogenous and endogenous precursors. The rates of direct and reverse reactions responsible for the interconversion of Chl aand Chl b depended on the stage of the formation of the photosynthetic apparatus during greening of etiolated seedlings, when the particular structural components are formed in a definite sequence.     

Caloric content of plant species and its role in a Leymus chinensis steppe community of Inner Mongolia, China

The caloric contents of 42 species and their composition in a Leymus chinensis steppe community of Inner Mongolia, China were determined and analyzed based on the field experiment for 11 years. The caloric content (x ± SD) of aboveground parts of plant species varied from (13156 ± 1141) J·g^?1 (ash contained) to (18141 ± 527) J·g^?1. The average caloric content of all species was (16899 ± 840) J·g^?1 and the inter-specific CV (coefficient of variation) was 4.9%. Of all the species, Caragana microphylla had the highest caloric content (18142 J·g^?1). Grasses had a higher average caloric content ((17425 ± 291) J·g^?1) than forbs ((16734 ± 844)J·g^?1). When the herbaceous species were classified into subgroups according to life-form and growth-form, the order of average caloric contents, from high to low, was: tall grasses ((17717 ± 92) J·g^?1) > legume ((17228 ± 433) J·g^?1) > short grasses ((17250 ± 218) J·g^?1) > remaining forbs ((16784 ± 529) J·g^?1) > subshrubs ((16719 ± 69) J·g^?1) > annuals and biennials ((15911 ± 1759) J·g^?1). There was a positive correlation (P < 0.05) between the caloric contents of 42 species and their relative biomass in the community. When all species were classified into 3 groups according to their composition in the community, the average caloric contents, weighed by the species relative biomass, followed the order: dominant (17740 J·g^?1) > companion (17244 J·g^?1) > incidental (16653 J·g^?1). The plants with high caloric contents were more competitive, which allowed them to gain a dominant status, whereas the competitive abilities of plants with low caloric contents were generally weak. The latter made up the companion or incidental species in a steppe community.     

Nucleic acids in mummified plant seeds: screening of twelve specimens by gel-electrophoresis,molecular hybridization and DNA cloning

Summary Twelve seed specimens of varying ages and from different archaeological sites were analyzed for the presence of polymerized DNA and RNA. Amongst the samples tested, one of Vitis vinifera from an archaeological site in Iran (2,000–3,000 B.C.) was found to be completely devoid of nucleic acids. Zea mais seeds of Precolumbial age from Peru (about 800 A.D.) contained depolymerized DNA and RNA. Samples of Vitis vinifera and Rubus sp. from a Lombard archaeological site (800 A.D.) as well as radiocarbon dated seeds from the site of the Spring Sanctuary near Metaponto (I–IV century B.C.) were found to contain polymerized DNA and rRNA bands. However the electrophoretic properties of the rRNAs in one case and hybridization experiments performed with cloned seed DNA in the other, clearly demonstrated that the polymerized nucleic acids were not of plant origin.     

花生种子相关促生菌分离鉴定及功能评价

【背景】利用微生物促进植物健康生长是农业可持续发展的重要方向之一,而种子相关的促生菌可在植物生命周期早期与植物相互作用,对植物健康生长具有重要意义。【目的】发掘与利用种子相关促生菌的前提是筛选获得促生菌菌种资源,验证其益生能力,为其进一步应用与机理研究提供依据与支持。【方法】以花生种子为研究对象,从种子表面及种子内部分离纯化多株菌,测定菌株的固氮、解磷、解钾、吲哚乙酸合成和铁载体合成等促生能力,并验证菌株对常见植物病原菌的生长抑制特性;通过16S rRNA基因序列进行系统发育分析,确定分类地位;通过生物膜形成能力及根际定殖能力测定菌株在植物根际的生存能力;最后通过催芽及盆栽试验测定菌株对花生种子发芽及幼苗生长的影响。【结果】从花生种子表面、种子内和胚根内分离筛选到41株菌,均有吲哚乙酸合成能力,其中35株有固氮能力,2株有铁载体分泌能力,14株有植物病原菌生长抑制能力。各选一株为代表的菌株,即PS3、PE5和PR5,经16S rRNA基因序列比对分析鉴定为芽孢杆菌属(Bacillus)。PS3、PE5和PR5均可在MSgg液体培养基表面形成褶皱较强的生物膜,也可在花生根际形成有效定殖。催芽试验结果表明经过促生菌浸种后花生种子萌发率明显提高,在第2天时,PS5将发芽率由14.17%提高至38.33%,PE5发芽率提高至30.83%,PR5发芽率提高至39.17%。三株菌能够明显促进花生幼苗生长,PS5对花生幼苗苗高、根长、鲜重和干重分别提高21.82%、22.20%、37.11%和35.64%,PE5分别提高17.45%、18.93%、26.10%和21.18%,PR5分别提高23.11%、23.92%、38.66%和37.47%。【结论】筛选获得的花生种子相关促生菌,具有促进植物生长的潜力,明显促进种子萌发及幼苗生长,是良好的促生菌生物资源,具有较好的应用潜力。     

Inhibition of pregerminative processes in dormant and thermodormant Agrostemma githago seeds

Imbibed non-dormant seeds do not germinate immediately after completion of water uptake and reactivation of their metabolism. During the lag-period the seeds apparently undergo processes which are essential for germination. The extent to which these pregerminative processes occur in dormant seeds (freshly harvested seeds) and thermodormant seeds (afterripened seeds imbibed at a supra-optimal temperature) of Agrostemma githago was determined. The pregerminative processes were inhibited almost completely in dormant seeds, but only to 50% or less in thermodormant seeds. When seeds were progressing through the pregerminative processes, the axes showed a higher rate of protein synthesis than axes of blocked seeds. However, this increased rate of protein synthesis was a late event and neither necessary nor sufficient for germination.     

Comparison of Spectrophotometric,Fluorometric and High Performance Liquid Chromatography Methods for Determination of Chlorophyll a in Aquatic Samples: Effects of Solvent and Extraction Procedures

Chlorophyll a determinations were made on lakewater and algal samples by spectrophotometric, fluorometric and high performance liquid chromatographic methods. Acetone, methanol and ethanol solvents were evaluated for their ability to extract photosynthetic pigments from Scenedesmus sp. cultures. Routinely used methods overestimated the chlorophyll a concentrations present in the samples. Significant differences resulted when various standard equations were used to calculate chlorophyll a concentrations. Acetone did not quantitatively extract chlorophyll pigments, even after 24 h. Mechanical disruption was found to be important in assuring complete extraction of the chlorophyll pigments.     

Proteinase activities in resting and germinating seeds of Scots pine, Pinus sylvestris

Resting seeds of Scots pine contained a moderate amount of acid proteinase activity, about 90% of which was inhibited by pepstatin A and about 10% by p-hydroxymer-curibenzoate. In gel chromatography on Sephacryl S-200 the proteinase activity showed a complex elution pattern with poorly separated peaks at positions corresponding to mol. wts. 100,000 and 30,000 and several shoulders. The results suggested that pine proteinases I and II, which are the main proteinases in the endosperms of germinating seeds (Salmia 1981: Physiol. Plant. 51: 253–258), were not present in the resting seeds.—Seedling extracts showed a low level of acid proteinase activity, which separated into several peaks in chromatography on Sephacryl S-200. As none of the peaks had the catalytic properties of proteinase I or II, it seems that these endospermal enzymes are also lacking in the seedling tissues.—In the endosperms of germinating seeds the activity of the pepstatin-sensitive acid proteinase(s) remained at a constant level throughout the period of reserve protein mobilization (lasting up to the stage when the length of dark-grown seedlings was 60 mm). Proteinases I and II were absent from resting seeds, showed a small increase up to the 20-mm stage, and then increased rapidly up to the 60-mm stage.—Resting embryos contained relatively higher acid proteinase activity than resting endosperms, and again about 90% of it was inhibited by pepstatin A and about 10% by p-hy-droxymercuribenzoate. During germination the former activity decreased, the latter activity remained at approximately the same level, and the activity of the other acid proteinases increased continuously with the growth of the seedling.—It is concluded that the pepstatin-sensitive proteinase(s), which is not affected by endogenous proteinase inhibitors, plays a central role in the initiation of reserve protein mobilization in both the embryo and the endosperm. Proteinases I and II, on the other hand, seem to account for the greater part of reserve protein breakdown in the main protein storage tissue, the endosperm.     

Ligand design,synthesis and biological anti-HCV evaluations for genotypes 1b and 4a of certain 4-(3- & 4-[3-(3,5-dibromo-4-hydroxyphenyl)-propylamino]phenyl) butyric acids and 3-(3,5-dibromo-4-hydroxyphenyl)-propylamino-acetamidobenzoic acid esters

4-(4-[N-1-carboxy-3-(3,5-dibromo-4-hydroxyphenyl)-3-oxo-propylamino]phenyl)-4-oxo-butyric acid (V), 4-(3- & 4-[N-1-carboxy-3-(3,5-dibromo-4-hydroxyphenyl)-3-oxo-propylaminophenyl]-2-aryl-4-oxo-butyric acids (Xa–e) and 4-(2-alkyl-2-[N-3-(3,5-dibromo-4-hydroxyphenyl)-1-carboxy-3-oxo-propylamino]acetamido) benzoate esters (XVa–e) were designed, synthesized and biologically evaluated as anti-HCV for genotypes 1b and 4a. The design was based on their docking scores with HCV NS3/4A protease-binding site of the genotype 1b (1W3C), which is conserved in the genotype 4a structure. The docking scores predicted that most of these molecules have higher affinity to the HCV NS3/4A enzyme more than Indoline lead. These compounds were synthesized and evaluated for their cytopathic inhibitory activity against RAW HCV cell cultures of genotype 4a and also examined against Huh 5–2 HCV cell culture of genotype 1b, utilizing Luciferase and MTS assays. Compounds Xa and Xb have 95 and 80% of the activity of Ribavirin against genotype 4a and compounds XVa, XVb and XVd exerted high percentage inhibitory activity against genotype 1b equal 87.7, 84.3 and 82.8%, respectively, with low EC₅₀ doses.     

小车前（Plantago minuta Pall.）种子表面粘液物质的吸水特性及其对种子在干旱环境中萌发的影响

为了理解荒漠短命植物小车前(Plantago minuta Pall.)种子表面的粘液物质对种子在干旱环境中萌发的作用,在室内控制条件下研究了粘液物质的吸水保水特性、剥离粘液物质的种子(无粘液种子)和保留粘液物质的种子(粘液种子)在-1.15～-0.15 MPa不同渗透胁迫条件下的萌发状况.结果表明: (1)小车前种子表面的粘液物质干重占粘液种子干重的5.6%;在去离子水中,粘液物质可以吸收相当于其自身干重217.1倍的水分;粘液物质的存在使得小车前种子的吸水倍数由2倍增加至14倍,从而保证为种子萌发提供充足的水分;(2)干燥的粘液种子吸水2h后即达到饱和,而吸水饱和后的粘液种子在室温下晾置,经过48h后又干燥失水恢复至原重;(3)在去离子水中或低渗透胁迫(-0.33～-0.15 MPa) 条件下,粘液物质吸水作用能促进小车前种子萌发,粘液种子3d的发芽势和10d的总萌发率均显著高于无粘液种子;在高渗透胁迫(-1.15～-0.73MPa)条件下,粘液种子3d的发芽势显著低于无粘液种子的,而10d的总萌发率与无粘液种子的没有显著差别,表明粘液物质在干旱条件下可能从种子而非外界环境中吸取水分,减缓了种子萌发速率.通过上述结果可以认为小车前种子表面的粘液物质在早春干湿交替剧烈的荒漠生境中起到通过调节水分来调节种子萌发的作用,这种萌发策略大大降低了因大批种子同时萌发导致幼苗受旱甚至种群灭亡的潜在风险.     

Impact of planting density and soaking seeds in melatonin solution on yield,secondary products content and antimicrobial activity of lovage plant

Many studies worldwide have been done on the effect of medicinal uses of lovage plant but, very little works have been done on its production. In this study the effect of different planting density and soaking seeds in different concentration of melatonin solution as well as their combination treatments on yield, secondary products content and antimicrobial activity of lovage plant were studied. It was observed that using planting space of 15 cm gave the maximum mean values of total phenolic and antioxidant content and essential oil percentage. Using 30 cm planting space gave the maximum mean values of plant height, yield of herb fresh and dry weight per hectare, yield of roots dry weight and essential oil per hectare. While the plant space of 45 cm recorded the maximum mean values of fresh and dry weight of herb and roots fresh weight per plant and chlorophyll content. For melatonin levels, using 100 µM melatonin solution had the minimum mean values of number of days to emergence. While, soaking seeds in 75 µM melatonin solution recorded the best results of all studied parameters. Regarding the combination treatments, measurements comprising of herb fresh and dry weight as well as essential oil yield per hectare showed that the combination treatment of 30 cm between plants in row plus soaking seeds in 75 µM melatonin solution was able to achieve the maximum values of these parameters. While the combination treatment of 15 cm between plants in row plus soaking solution of 75 µM melatonin is recommended for getting the maximum yield of root fresh and dry weight per hectare and the maximum total phenolic and antioxidant contents per herb in both cuts of both studied season. The first major compound of lovage essential oil of herb is α-terpinyle acetate followed by β-Phellandrene. The percentages of these compounds were affected by the applied treatments. The volatile oil of lovage plant exhibits high antibacterial and antifungal properties in the concentrations range of 75–100 µg mL⁻¹.Abbreviation: MBC, minimal bactericidal concentration; MFC, minimal fungicidal concentration     

Effect of nitrogen on carbonic anhydrase activity, stomatal conductance, net photosynthetic rate and yield of mustard

Mustard (Brassica juncea L.) cv. Rohini was grown under three levels of urea nitrogen fertilization [0, 2, and 4 g(N) pot^-1]. Carbonic anhydrase activity and net photosynthetic rate in leaves of 50 d-old plants as well as yield attributes at harvest increased with increasing levels of nitrogen. Stomatal conductance was not affected, and oil content decreased. This revised version was published online in June 2006 with corrections to the Cover Date.