精密组织切片的制备及其应用

精密组织切片是被研究人员广泛使用的器官体外模型,它保持了体外系统的主要优点,弥补了细胞系所缺失的功能,能充分维持组织活性、功能活性以进行毒性、诱导和感染研究.本文简要介绍了精密组织切片技术的发展进程、优点以及应用前景,对精密组织切片的制备方法、培养体系和活性测定指标,以及精密组织切片技术作为一种新型的离体模型应用于各个...     

超声提取桂西生姜色素的最佳工艺及稳定性研究

[目的]探索超声提取桂西生姜色素的最佳工艺及稳定性。[方法]以生姜为原料,采用单因素试验,研究不同料液比、提取温度、超声功率和提取时间对生姜色素提取效果的影响,再采用正交试验确定超声提取生姜色素的最佳工艺条件;通过稳定性试验,研究pH、温度、金属离子、常见食品添加剂、氧化剂和还原剂以及太阳光照对生姜色素稳定性的影响。[结果]生姜色素的最佳提取工艺条件为料液比1∶30,提取温度65℃,超声功率140 W,提取时间40 min。生姜色素在酸性条件下较稳定,耐热性较好,耐光性较差,耐氧化还原性较强;苯甲酸钠和柠檬酸对生姜色素稳定性的影响较大;金属离子中,Ni2+、Fe3+、Cu2+对色素稳定性有一定影响,以Fe3+影响最大。[结论]该研究为生姜色素的开发和利用奠定了理论基础。     

免炕壮苗素对生姜生长及产量和品质的影响

研究了生姜上炕人工催芽与"免炕壮苗素"浸种直播对不同生姜品种产量、品质和农艺性状、病虫害的影响。试验结果表明,莱芜大姜应用"免炕壮苗素"比上炕人工催芽产量高19.8%,莱芜小姜为10%。在生姜生长因子适宜的范围内,用"免炕壮苗素"浸种直播越早,生姜产量越高,且生长量大,生长势强,品质良好。与上炕人工催芽相比,"免炕壮苗素"浸种直播生姜株高、有效叶数、根茎鲜重、茎粗、分枝数增幅分别达到7.3%7、.8%、18.4%、15.1%和16.2%以上,根茎中可溶性糖、VC、挥发油含量分别提高31.5%、10.6%和25%以上。对生姜姜瘟病防效达50%,姜螟亦有所减轻,但效果不显著。"免炕壮苗素"对生姜生长的影响主要为迅速打破休眠,提高长势及免疫性能,改善生姜品质,且对不同品种增产效应有差异。     

Garlic and ginger extracts modulated broiler chicks innate immune responses and enhanced multidrug resistant Escherichia coli O78 clearance

Administration of antibiotics as feed additives in broilers resulted in prompting of some undesirable effects such as the rising emergence of multi-drug resistant (MDR) bacteria, so scrutinizing for new alternatives like herbs is the up to date task for global health. This study was designed to determine the in-vitro antibacterial and ex-vivo immunomodulatory efficacy of garlic (Allium sativum) and ginger (Zingiber officinale) extracts post dietary supplementation for 900-one-day-old Sasso broiler chicks. The in-vivo protective actions of these extracts against avian pathogenic MDR Escherichia coli (E. coli) O78 challenge was evaluated after 21 days of extracts supplementation. Garlic extract exhibited broader antimicrobial spectra against MDR E. coli O78 and S. aureus isolates. Through the 21 days of garlic or ginger dietary supplementation, the chicks’ innate immune response was modulated via various mechanisms including phagocytosis augmentation, bactericidal activity enhancement and nitric oxide (NO) production reduction, together with triggering the IL-1β, IL-6 and IFN-γ cytokines expression levels in comparison with the non-supplemented chicks. It is tempting to speculate that protection against pathogenic E. coli O78 challenge was high in chicks supplemented with each individual extract with severe reduction in the bacterial colony forming units in chicks’ vital organs that confirm the extracts immunomodulatory activity and provide a mechanism(s) of their protective actions. Our data suggest promising useful insights to garlic and ginger dietary supplementation in broilers that may be safe for consumers from antibiotic toxic metabolites’ residues and protective against the risk of infection with bacterial pathogens.     

Allelopathic effect of ginger on seed germination and seedling growth of soybean and chive

The rhizome, stem and leaf aqueous extracts of ginger were assayed at 10, 20, 40, and 80 g l⁻¹ for their effects on seed germination and early seedling growth of soybean and chive. All aqueous extracts at all concentrations inhibited seed germination, seedling growth, water uptake and lipase activity of soybean and chive compared with the control, and the degree of inhibition increased with the incremental extracts concentration. The degree of toxicity of different ginger plant parts can be classified in order of decreasing inhibition as stem > leaf > rhizome. The results of this study suggest that rhizome, stem and leaf of ginger contain water-soluble allelochemicals which could inhibit seed germination and seedling growth of soybean and chive. The rhizome is the main harvested part of ginger. The residue (mainly stems and leaves) of the ginger plant should be removed from the field so as to diminish its inhibitory effect. Further work is needed to specify and verify the allelochemicals produced by this plant. The results of this study suggest that ginger allelochemicals are heterotoxic, and thus intercropping should not be practiced using ginger.     

蔗糖浓度对生姜试管苗生长及内源激素变化的影响

随蔗糖浓度的提高,生姜试管苗的株高显著降低,而繁殖系数显著增加,蔗糖浓度超过80 g·L~(-1)时,繁殖系数则显著降低。不同蔗糖浓度处理生姜试管苗叶片及根状茎內源激素IAA、ZR变化较小;而GA则随蔗糖浓度的提高呈下降趋势;蔗糖浓度在20～50 g·L~(-1)范围内叶片ABA变化不大,而根状茎ABA则迅速降低,蔗糖浓度超过50 g·L~(-1),叶片ABA迅速增加,而根状茎ABA则变化不大。生姜试管苗根状茎形成与叶片及根状茎内源激素ABA/GA密切相关,相关系数分别为0.935 8和0.996 7。蔗糖浓度80～110 g·L~(-1)时,叶片ABA/GA在1.0～1.4之间,诱导根状茎效果较好。     

生姜高产优化施肥最佳方案的选择与分析

采用二次正交旋转回归设计法,进行了生姜N、P₂O₅、K₂O肥施用量的试验,建立了生姜产量与N、P₂O₅、K₂O肥用量间的三元二次数学模型.通过对模型解析得出,N肥用量对生姜产量影响最大,但用量过多会引起减产.应用计算机模拟寻优,筛选出试验条件下亩产超2500kg的农艺方案14个,最高产量为2614.06kg/亩,相应的肥料用量为N38.69 kg,P₂O₅ 18.91kg、K₂O51.90kg,其比例为2:1:2.7.     

射频加热烫漂对苹果片理化性质和微观结构的影响

烫漂是苹果乃至果蔬加工业中的一个重要步骤。采用中试型射频加热系统,在不同极板间距下对苹果片进行射频加热,测定射频加热升温曲线和均匀性,测定 颜色、质构、多酚氧化酶（PPO）活性和重量的变化,采用扫描电子显微镜(SEM)观察射频加热过程中苹果片的微观结构,揭示苹果片射频加热烫漂过程中理化 特性变化的机理。结果表明：115 mm时升温速度最快而125 mm下升温最慢,从22℃升到95℃,分别需95 s和140 s;苹果片呈现中间温度高,边缘温度低的现象 。苹果片射频加热的PPO相对酶活是射频加热温度和持续时间的双重作用。随着烫漂温度的升高护色效果变好,苹果片硬度随着烫漂温度的升高而减小。苹果片 细胞破坏程度随着烫漂温度的升高而增大,升温速度越快苹果片细胞破坏越小。苹果片最佳的射频加热条件为极板间距105 mm下加热101 s。     

高效液相色谱-质谱法测定香姜中有机氯农药残留

[目的]建立高效液相色谱-质谱法(HPLC-MS)测定香姜中有机氯农药残留分析方法。[方法]采用正己烷-丙酮(4∶1)超声提取,过滤,盐析,干燥,经弗洛里硅土柱净化,用丙酮+正己烷(10+90)洗脱,用高效液相色谱-质谱联用法检测香姜中有机氯农药残留。[结果]试验表明,有机氯农药标准的线性范围2~50μg/L,相关系数r均在0.99以上,在5、10、20μg/L加标水平下,平均回收率分别为80.0%~95.7%、82.4%~97.2%和83.6%~98.3%;相对标准偏差(RSD)分别为4.2%~9.8%、1.8%~9.4%和2.6%~8.8%。方法检出限(信噪比S/N≥3)均为1μg/kg,方法定量下限(信噪比S/N≥10)均为5μg/kg。[结论]该方法简单、快速、准确,灵敏度和精密度好,适合香姜中有机氯农药残留的测定。     

微波真空干燥条件对苹果脆片感官质量的影

选择微波功率、真空度和初始含水率为自变量,采用二次回归正交旋转组合设计结合响应面法,建立了微波真空干燥苹果脆片感官质量的回归模型,分析了各试验因素及交互作用对感官质量的影响规律,获得较高感官质量的工艺条件理想取值区间:微波功率10.6～12.7 W/g、真空度0.083～0.094 MPa和初始含水率0.6～0.9.获得高品质苹果脆片的最佳工艺条件为:微波功率11.7 W/g、真空度0.089 MPa、初始含水率0.75, 感官质量预测得分可达到9.51.通过试验验证,感官质量实测平均得分值为9.42,进一步证明回归模型具有较好的拟合度.