关键栽培措施对菜籽油综合品质的影响

为明确关键栽培措施对菜籽油品质的影响,本研究以“湘杂油518”和“大地199”为材料,分别在武汉和兰州进行播期、密度及氮肥处理单因素试验,籽粒成熟后收获冷榨,测定菜籽油色泽、过氧化值、极性总酚及甾醇含量等关键品质指标,综合评价各处理下菜籽油品质。结果表明:本试验条件下,播期、密度、氮肥均显著影响菜籽油关键品质指标,但各指标在两品种、两试验点间的变化规律不尽相同。两试点、两品种均在早播条件下菜籽油的油酸含量较高,且均随播期推迟,色泽加深,叶绿素含量升高,综合品质下降。两试点的湘杂油518品种在D2密度(4.5×10^(5)hm^(–2))下的菜籽油的酸价较低,极性总酚、总植物甾醇和总生育酚含量较高,综合品质较好。两试点的大地199品种则随密度增加菜籽油叶绿素含量增加,色泽加深,亚油酸含量降低,综合品质下降。两试点、两品种均在低氮下(120 kg hm^(–2))有较高的籽粒含油量和出油效率,且均随施氮量的增加菜籽油色泽加深,综合品质下降。主成分分析表明,播期对菜籽油综合品质的影响大于种植密度和施氮量处理,酸价、叶绿素、极性总酚、抗氧化能力和总植物甾醇是影响菜籽油的关键品质指标;相关性分析表明,籽粒含油量与出油效率显著正相关,叶绿素、类胡萝卜素与菜籽油色泽均呈显著正相关,极性总酚与抗氧化性显著正相关。综上所述,生产中适期早播、减少氮肥用量、降低种植密度,可提高压榨菜籽油品质。本试验结果可为高品质菜籽油优质原料的生产提供技术支撑。

长江流域不同生态区油菜籽关键品质比较研究

本研究选用长江流域上中下游各6个油菜品种,采用相同栽培措施在四川、湖北与浙江试验点种植,籽粒成熟后收获冷榨,测定菜籽油不饱和脂肪酸(USFAs)组成及叶绿素、极性总酚、植物甾醇、生育酚等含量等指标,凝炼各试点菜籽油关键特征。结果表明,油菜籽粒含油量、出油效率指标,菜籽油中叶绿素、极性总酚、植物甾醇、生育酚含量等指标在试点间均存在差异。(1)籽粒含油量四川优于湖北,浙江试点最低,并且中下游地区的品种在四川种植,含油量增加;浙江试点的籽粒出油效率最高,其次为四川试点,湖北试点最低。(2)四川试点菜籽油油酸含量最高,其次为浙江试点,湖北试点最低,但湖北试点有较高的亚油酸和亚麻酸含量;菜籽油极性总酚与植物甾醇含量在四川试点最高,其次为湖北试点,浙江试点最低;菜籽油生育酚含量及外观品质则相反,浙江试点最佳,其次则依次为湖北、四川试点。(3)四川试点的菜籽油抗氧化能力优于湖北,浙江试点最低,四川试点较强的抗氧化能力主要得益于油菜角果期较低的温度与降雨量。综上,长江流域不同试验点菜籽油品质存在差异。本研究结果可为各生态区优质油菜品种选用提供参考。

种植密度对油菜正反交组合产量与倒伏相关性状的影响

高产抗倒不协调是油菜生产中最主要的矛盾,严重制约着油菜生产效益的进一步提高。在高密度、机械化生产模式下,这种矛盾尤为突出。受母系遗传的影响,杂交油菜的正、反交组合在产量与倒伏相关性状上常表现出明显差异,但种植密度对不同杂交组合这些关键性状的影响尚不明确。本研究针对浙油50、华航901及其正交(华航901×浙油50)与反交(浙油50×华航901)组合设置5个种植密度,考察其产量及倒伏相关性状并计算其杂种优势,研究种植密度对亲本及正、反交组合产量与倒伏相关性状的影响,为当前高密度直播生产模式下杂交油菜亲本的选配提供依据。结果表明,随种植密度增加,亲本及正、反交组合的实际产量和经济系数均呈先增后降的趋势,且无论正、反交组合,其实际产量的动态变化规律均与父本更为接近;倒伏指数在两点随种植密度的变化规律不同,但无论正、反交组合,其倒伏指数的动态变化规律均与母本相一致。在西宁试点,杂交组合产量均具有明显的平均杂种优势,且正交组合比反交组合具有更大的杂种优势;正交组合具有一定的抗倒性杂种优势,但是反交组合无抗倒性杂种优势。综上所述,高密度直播生产模式下,杂交油菜亲本选配推荐方案以高产品种为父本,抗倒性强的品种为母本进行组配,可以获得高产、抗倒性强且更适宜密植的杂交油菜品种。

长江流域迟播甘蓝型油菜播种期和播种量优化配置研究

为解决长江流域稻油茬口矛盾,提高冬闲田利用率,亟须迟播油菜(10月25日之后播种)配套技术研究。本研究以早熟品种‘华油杂137’为材料,在湖北武汉进行2年播种期(10月25日至11月15日间,各播种期间隔3 d,用S1~S8表示)和播种量(2.5、5.0、7.5、10.0和12.5 kg hm^(-2),用R1~R5表示)单因素试验,考察生育期、成苗动态、农艺性状、产量和倒伏指标,统计有效积温,通过线性回归和平滑曲线拟合分析,优化播种期和播种量的配置参数,为迟播油菜生产提供技术支撑。结果表明,(1)播种期推迟,迟播油菜的生育期缩短、根颈粗降低、分枝数减少、产量降低且茎秆倒伏指数增加;4个生育期中,苗期和花期有效积温与产量呈极显著正相关。(2)播种量增加,各生育期成苗数和收获密度提高,但生育期缩短、有效积温减少,角果层厚度降低、倒伏指数先降后增、产量呈先增后降趋势。(3)2年不同播种期产量数据回归分析表明,播种期推迟至S3~S4时,越冬前有效积温保持在317.1℃以上,苗期有效积温达401.1℃,终花35 d收获产量可达2700.0 kg hm^(-2),倒伏指数为1.5左右;2年不同播种量产量数据平滑曲线拟合分析表明,不同播种量下收获密度与产量呈抛物线关系,收获密度为64.2×10^(4)株hm^(-2)时终花35 d收获产量达峰值,为2948.5 kg hm^(-2),而倒伏指数为1.6。综上,配置7.5~10.0 kg hm^(-2)的播种量确保收获密度达64.2×10^(4)株hm^(-2),抢时播种确保冬前有效积温达317.1℃,可显著提高迟播油菜产量与抗倒性。

Induction of actin disruption and downregulation of P-glycoprotein expression by solamargine in multidrug-resistant K562/A02 cells

Background Solamargine （SM）, a steroidal glycoalkaloid isolated from the Chinese herb Solanum incanum, has been shown to inhibit the growth of some cancer cell lines and induce significant apoptosis. However, the effects of SM on multidrug-resistant （MDR） cells and the molecular mechanisms involved are poorly understood. The purpose of this study was to evaluate the anti-MDR effects of SM and the associated mechanisms in MDR K562/A02 cells. Methods The cytotoxicity of SM was measured by 3-（4,5-dimethylthiazol）-2,5-diphenyltetrazolium bromide （MTT） assay. The 14＇,6-diamidino-2-phenylindole （DAPi） nuclear staining and flow cytometry were used to detect SM-induced apoptosis. The mRNA expression of P-glycoprotein （P-gp） was investigated by real-time PCR （RT-PCR）. Western blotting was used to determine the expression of Bcl-2, Bax, and actin. The changes in the morphology of actin were examined with immunofluorescence staining. Results MTT results showed that SM effectively killed the MDR sublines K562/A02, KB/VCR, and H460/paclitaxel （Taxol）, and their parental cell lines K562, KB, and H460 to an equivalent or more sensitive degree. Based on the results by flow cytometry and immunostaining, the pro-apoptotic effects of SM were observed in MDR K562/A02 cells. Furthermore, the RT-PCR results showed that SM induced the downregulation of MDR1 mRNA. In addition, the expression of P-gp and actin was decreased in the SM-treated cells, as measured by western blotting and immunostaining. Conclusions These results demonstrate that SM effectively triggers apoptosis in MDR tumor cells, which is associated with actin disruption and downregulation of MDR1 expression. This compound may merit further investigation as a Potential therapeutic aaent that bvDasses the MDR mechanism for the treatment of MDR tumors.

Pre-treatment with puerarin affects pharmacokinetics of warfarin, but not clopidogrel, in experimental rats

The present study was designed to determine the effects of puerarin pre-treatment on the pharmacokinetics of the oral anticoagulant agent warfarin and the antiplatelet agent clopidogrel in rats. In the treatment group, rats was gavaged with warfarin or clopidogrel after repeated treatment with puerarin at intraperitoneal doses of 20, 60, or 200 mg·kg-1 for 7 days, while rats in the control group were administrated only with the same dose warfarin or clopidogrel. Plasma samples were obtained at the prescribed times and analyzed by liquid chromatography tandem mass spectrometry(LC-MS/MS). The results showed that rats treated with puerarin at all the test doses of 20, 60 and 200 mg·kg-1 were found to affect the pharmacokinetics of warfarin, but not clopidogrel, suggesting a potential herb-drug interaction between puerarin and warfarin.

Scapaundulin C,a novel labdane diterpenoid isolated from Chinese liverwort Scapania undulate,inhibits acetylcholinesterase activity

In the present study, scapaundulin C(1), a new labdane diterpenoid, and four related known compounds scapaundulin A(2), 5?, 8?, 9?-trihydroxy-13E-labden-12-one(3), 5?, 8?-dihydroxy-13E-labden-12-one(4), and(13S)-15-hydroxylabd-8(17)-en-19-oic acid(5), were isolated from the Chinese liverwort Scapania undulate(L.) Dum., using column chromatography. The structures of these compounds were determined on the basis of 1D- and 2D-NMR analyses. The acetylcholinesterase(Ach E) inhibitory activity was evaluated using a bioautographic TLC assay and the cytotoxic activity was evaluated by the MTT method. All the compounds were reported for the first time to exhibit moderate Ach E inhibitory activity with minimal inhibitory quantities ranging from 250 to 500 ng. All the compounds were tested for their cytotoxicity against five human tumor cell lines, A549, K562, A2780, Hela, and HT29, and compounds 3 and 4 exhibited moderate inhibitory effects on the growth of A2780 cells.

Two natural molecules preferentially inhibit azole-resistant Candida albicans with MDR1 hyperactivation

Antifungal drug resistance is a significant clinical problem, and antifungal agents that can evade resistance are urgently needed. In infective niches, resistant organisms often co-existed with sensitive ones, or a subpopulation of antibiotic-susceptible organisms may evolve into resistant ones during antibiotic treatment and eventually dominate the whole population. In this study, we established a co-culture assay in which an azole-resistant Candida albicans strain was mixed with a susceptible strain labeled with green fluorescent protein to mimic in vivo conditions and screen for antifungal drugs. Fluconazole was used as a positive control to verify the validity of this co-culture assay. Five natural molecules exhibited antifungal activity against both susceptible and resistant C. albicans. Two of these compounds, retigeric acid B(RAB) and riccardin D(RD), preferentially inhibited C. albicans strains in which the efflux pump MDR1 was activated. This selectivity was attributed to greater intracellular accumulation of the drugs in the resistant strains. Changes in sterol and lipid compositions were observed in the resistant strains compared to the susceptible strain, and might increase cell permeability to RAB and RD. In addition, RAB and RD interfered with the sterol pathway, further aggregating the decrease in ergosterol in the sterol synthesis pathway in the MDR1-activated strains. Our findings here provide an alternative for combating resistant pathogenic fungi.

Old fusidane-type antibiotics for new challenges:Chemistry and biology

The spread of antibiotic-resistant bacteria and exhausted drug leads render some infections untreatable now and in the future.To deal with these“new challenges”,scientists tend to re-pick up“old antibiotics”.Fusidane-type antibiotics have been known for nearly 80 years as potent antibacterial agents against gram-positive bacteria,especially Staphylococci,and represent the only triterpene-derived antibiotic class in clinical setting.These attractive characteristics have drawn renewed attention on fusidane-type antibiotics in recent decades.Isolation,characterization,biological evaluation,as well as chemical modifications of fusidane-type antibiotics are increasingly being reported.Combinatorial biosynthesis of this type of antibiotics has been successfully utilized not only for elucidating the biosynthetic pathways,but also for expanding their structural diversity.Some isolated and synthetic compounds exhibit comparable or even more potent biological activity than fusidic acid.This review provides an overview of progress on the studies of structure and biology of fusidane-type antibiotics from 1943 to April 2021.The informative structure-activity relationship is also highlighted.

Seasonal Variation,Microscopic and Chromatographic Analysis of Leaves in Malus hupehensis:A Protocol for Its Quality Control

Objective To establish a quality control protocol based on microscopic, TLC, and HPLC methods, and to verify the optimal harvesting time for the leaves of Malus hupehensis(LMH). Methods The LMH were pulverized into powder for microscopic identification or TLC and HPLC analysis after ultrasonic extraction with methanol. Seasonal variations of the phlorizin content and average leaf weight were determined by HPLC analysis and weighing up the leaves collected from May to October. Results Microscopic and macromorphologic characteristics have been described for the leaf identification. A qualitative TLC assay and a quantitative HPLC method have been established for the quality control of LMH. Phlorizin was selected as a reference marker, which resolved at Rf 0.53 in TLC assay and at 14.0 min in HPLC assay. The content of phlorizin decreased gradually from 17.0% in leaves collected in May to 7.5% in October. The average leaf weight reached the level of 0.6 g in August and maintained until its falling.Conclusion These methods are simple, selective, accurate, and reliable for the quality control of LMH. The period from late August to early September is suggested as the optimal harvesting time of the LMH.