Artificial Brassica napus flowering in Bangladesh

Summary Natural rapeseed (Brassica napus L.; AACC 2n=38), originated in the temperate climate of the Southwest European Mediterranean region, fails to complete its generative phase in the subtropics and is thus not cultivated in countries like Bangladesh. Adapted agroecotypes are available from the diploid representatives of its genome A (B. campestris/pekinensis, 2n=20) and C (B. oleracea/alboglabra, 2n=18). An artificial resynthesis based on carefully selected progenitor lines was expected to give a photoperiodically better adapted rapeseed. B. pekinensis x B. oleracea/alboglabra gave 2 hybrids and 87 matromorphous plants from 1,448 crossed flowers and the reciprocal combination gave no hybrid but 11 matromorphous plants from 2,228 pollinated flowers. The two true hybrids were vegetatively propagated and chromosome doubled. Part of the F₂ was grown in Sweden (all plants flowered and the most early ones were selected), part in Bangladesh (13 out of 706 plants flowered). The selected F₃ material flowered in Bangladesh and transgressions in earliness could be recorded, some lines were of definite agronomic potential. A correlation in earliness between reaction in Sweden (long day) and Bangladesh (short day) was observed.     

库车种子植物区系垂直分布格局分析

该研究通过野外植被调查及相关文献资料查阅,探讨了库车山区种子植物区系的垂直分布格局特征及其对海拔变化的响应。结果表明:该区种子植物约有78科376属960种。其中,裸子植物3科3属9种,被子植物75科373属951种。植物科、属、种总数随着海拔的升高呈现先增加后降低的单峰分布结构。其中科总数在海拔1 600~1 800 m处为最高峰,属总数在海拔1 800~1 900 m处呈现最高峰;物种总数在海拔1 900~2 000 m处呈现最高峰,有478种(隶属59科,230属)。种子植物区系地理成分分析中,库车山区植物区系垂直海拔梯度上不管是科级水平还是属级水平种类成分都以温带分布型占优势。在垂直分布梯度上,温带分布科最高点出现在海拔1 800~1 900 m(含20科),从海拔2 800~2 900 m开始,随着海拔梯度升高呈现下降趋势,到海拔3 600~3 700 m时为最低点(含6科);温带分布属峰值出现在海拔1 900~2 000 m,随着海拔的升高呈现下降趋势。该研究结果对该区植物种质资源和生态系统多样性,植物资源的引种驯化、栽培和合理利用具有重要意义。     

Encapsulation of soybean meal with fats enriched in palmitic and stearic acids: effects on rumen-undegraded protein and in vitro intestinal digestibility

Fat coating of soybean meal (SBM) can reduce its protein degradability in the rumen, but the encapsulation of SBM with palmitic (PA) and stearic acids (SA) has not yet been investigated, despite both fatty acids are common energy sources in dairy cow diets. This study aimed to evaluate the effects of applying a novel method, using either 400 or 500 g fat/kg (treatments FL40 and FL50, respectively), which was enriched in PA and SA at different ratios (100:0, 75:25, 50:50, 25:75 and 0:100), on physical and chemical characteristics, ruminal degradability, solubility and in vitro intestinal protein digestibility (IVIPD) of the obtained products. Encapsulation of SBM in fat resulted in greater mean particle size and lower bulk density and protein solubility than unprotected SBM (USBM). Treatment FL50 resulted in increased (p < 0.01) rumen-undegraded protein (RUP) compared to USBM. There were no differences in RUP of SBM when different PA: SA ratios were used. The mean RUP content of treatments FL40 and FL50 (306 and 349 g/kg, respectively) was greater compared to USBM (262 g/kg, p < 0.05), but lower than that for a standard heat-treated SBM (431 g/kg). Values of IVIPD did not differ among SBM, heat-treated SBM and FL40 and FL50 samples, all being greater than 97.8%. In conclusion, encapsulation of SBM with fats enriched in PA and SA proved to be effective in reducing protein solubility and increasing RUP without depressing protein digestibility in the intestine. For validation of the method, in vivo research to investigate the effects of these products on the production of dairy cows is warranted.     

Effect of NaCl concentrations in irrigation water on growth and polyamine metabolism in two citrus rootstocks with different levels of salinity tolerance

Six-months-old, uniform sized seedlings of two citrus rootstocks; Cleopatra mandarin (Citrus reshni Hort. ex Tan) and Troyer citrange (Poncirus trifoliata × Citrus sinensis) were irrigated with half-strength Hoagland nutrient solution containing 0, 40 or 80 mM NaCl for 12 weeks. Shoot height, leaf number and fresh weights of the seedlings, and relative chlorophyll contents, chlorophyll fluorescence yields (Fv/Fm), net photosynthetic and respiration rates in the leaves decreased with the increase in salinity level in the irrigation water. The decrease was greater in Troyer citrange as compared to Cleopatra mandarin. The concentrations of sugars i.e. fructose, glucose and sucrose in the leaves of Cleopatra mandarin and both leaves and roots of Troyer citrange decreased with the increase in salinity level. However, the concentrations in the roots of Cleopatra mandarin increased with the increase in salinity level. Free proline content in the leaves of Troyer citrange and root tissue of Cleopatra mandarin also increased with the increased salinity level. Among the polyamines, spermine titer increased in the leaves of both rootstocks as a response to salinity treatments. Na⁺ concentrations were higher in leaf and root tissue of Cleopatra mandarin, while that of Cl⁻ were higher in Troyer citrange.     

Discovery of 3-hydroxy-4-cyano-isoquinolines as novel, potent, and selective inhibitors of human 11β-hydroxydehydrogenase 1 (11β-HSD1)

Derived from the HTS hit 1, a series of hydroxyisoquinolines was discovered as potent and selective 11β-HSD1 inhibitors with good cross species activity. Optimization of substituents at the 1 and 4 positions of the isoquinoline group in addition to the core modifications, with a special focus on enhancing metabolic stability and aqueous solubility, resulted in the identification of several compounds as potent advanced leads.     

Essential roles of core starvation-stress response loci in carbon-starvation-inducible cross-resistance and hydrogen peroxide-inducible adaptive resistance to oxidative challenge in Salmonella typhimurium

The starvation-stress response (SSR) of Salmonella typhimurium encompasses the physiological changes that occur upon starvation for an essential nutrient, e.g. C-source. A subset of SSR genes, known as core SSR genes, are required for the long-term starvation survival of the bacteria. Four core SSR loci have been identified in S. typhimuriumrpoSstiAstiB, and stiC. Here we report that in S. typhimurium C-starvation induced a greater and more sustainable cross-resistance to oxidative challenge (15 mM hydrogen peroxide (H₂O₂) for 40 min) than either N- or P-starvation. Of the four core SSR loci, only rpoS and stiC mutants exhibited a defective C-starvation-inducible cross-resistance to H₂O₂ challenge. Interestingly, (unadapted) log-phase S. typhimurium rpoS and stiA mutants were very sensitive to oxidative challenge. Based on this, we determined if these core SSR loci were important for H₂O₂ resistance developed during a 60 min adaptive exposure to 60 μM H₂O₂ (adapted cells). Both unadapted and adapted rpoS and stiA mutants were hypersensitive to a H₂O₂ challenge. In addition, a stiB mutant exhibited normal adaptive resistance for the first 20 mins of H₂O₂ challenge but then rapidly lost viability, declining to a level of about 1.5% of the wild-type strain. The results of these experiments indicate that: (i) the rpoS and stiC loci are essential for the development of C-starvation-inducible cross-resistance to oxidative challenge, and (ii) the rpoSstiA, and, in a delayed effect, stiB loci are needed for H₂O₂-inducible adaptive resistance to oxidative challenge. Moreover, we found that both stiA and stiB are induced by a 60 μM H₂O₂ exposure, but only stiA was regulated (repressed) by (reduced form) OxyR.     

Spectral lights trigger biomass accumulation and production of antioxidant secondary metabolites in adventitious root cultures of Stevia rebaudiana (Bert.)

Stevia rebaudiana (S. rebaudiana) is the most important therapeutic plant species and has been accepted as such worldwide. It has a tendency to accumulate steviol glycosides, which are 300 times sweeter than marketable sugar. Recently, diabetic patients commonly use this plant as a sugar substitute for sweet taste. In the present study, the effects of different spectral lights were investigated on biomass accumulation and production of secondary metabolites in adventitious root cultures of S. rebaudiana. For callus development, leaf explants were excised from seed-derived plantlets and inoculated on a Murashige and Skoog (MS) medium containing the combination of 2,4-dichlorophenoxy acetic acid (2, 4-D, 2.0 mg/l) and 6-benzyladenine (BA, 2.0 mg/l), while 0.5 mg/l naphthalene acetic acid (NAA) was used for adventitious root culture. Adventitious root cultures were exposed to different spectral lights (blue, green, violet, red and yellow) for a 30-day period. White light was used as control. The growth kinetics was studied for 30 days with 3-day intervals. In this study, the violet light showed the maximum accumulation of fresh biomass (2.495 g/flask) as compared to control (1.63 g/flask), while red light showed growth inhibition (1.025 g/flask) as compared to control. The blue light enhanced the highest accumulation of phenolic content (TPC; 6.56 mg GAE/g DW), total phenolic production (TPP; 101 mg/flask) as compared to control (5.44 mg GAE/g DW; 82.2 mg GAE/g DW), and exhibited a strong correlation with dry biomass. Blue light also improved the accumulation of total flavonoid content (TFC; 4.33 mg RE/g DW) and total flavonoid production (TFP; 65 mg/flask) as compared to control. The violet light showed the highest DPPH inhibition (79.72%), while the lowest antioxidant activity was observed for control roots (73.81%). Hence, we concluded that the application of spectral lights is an auspicious strategy for the enhancement of the required antioxidant secondary metabolites in adventitious root cultures of S. rebaudiana and of other medicinal plants.     

Fruit Bats (Chiroptera: Pteropodidae) as Seed Dispersers and Pollinators in a Lowland Malaysian Rain Forest1

The aims of this study were to (1) characterize the food resources exploited by fruit bats (Pteropodidae) within an old‐growth Malaysian dipterocarp forest, (2) test the viability of the seeds they disperse, and (3) provide an estimate of the proportion of trees that are to some degree dependent upon bats for seed dispersal and/or pollination. Fruit species exploited by bats could be distinguished from those eaten by birds largely on the basis of color (as perceived by human beings). Bat‐dispersed fruits were typically inconspicuous shades of green–yellow or dull red–brown, whereas fruits eaten by birds were generally bright orange to red. Dietary overlap between bats and nonflying mammals was relatively high. In contrast to primates and squirrels, which were major seed predators for several of the plant species under investigation, fruit bats had no negative impact on seed viability. A botanical survey in 1 ha of old‐growth forest revealed that 13.7 percent of trees (?15 cm girth at breast height) were at least partially dependent upon fruit bats for pollination and/or seed dispersal.     

Synthesis and Biological Evaluation of 1,3,5-Trisubstituted 2-Pyrazolines as Novel Cyclooxygenase-2 Inhibitors with Antiproliferative Activity

A new series of 1,3,5-trisubstituted 2-pyrazolines for the inhibition of cyclooxygenase-2 (COX-2) were synthesized. The designed structures include a COX-2 pharmacophore SO₂CH₃ at the para-position of the phenyl ring located at C-5 of a pyrazoline scaffold. The synthesized compounds were tested for in vitro COX-1/COX-2 inhibition and cell toxicity against human colorectal adenocarcinoma cell lines HT-29. The lead compound (4-chlorophenyl){5-[4-(methanesulfonyl)phenyl]-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl}methanone ( 16 ) showed significant COX-2 inhibition (IC₅₀=0.05±0.01 μM), and antiproliferative activity (IC₅₀=5.46±4.71 μM). Molecular docking studies showed that new pyrazoline-based compounds interact via multiple hydrophobic and hydrogen-bond interactions with key binding site residues of the COX-2 enzyme.