Olive Varieties under UV-B Stress Show Distinct Responses in Terms of Antioxidant Machinery and Isoform/Activity of RubisCO

In recent decades, atmospheric pollution led to a progressive reduction of the ozone layer with a consequent increase in UV-B radiation. Despite the high adaptation of olive trees to the Mediterranean environment, the progressive increase of UV-B radiation is a risk factor for olive tree cultivation. It is therefore necessary to understand how high levels of UV-B radiation affect olive plants and to identify olive varieties which are better adapted. In this study we analyzed two Italian olive varieties subjected to chronic UV-B stress. We focused on the effects of UV-B radiation on RubisCO, in terms of quantity, enzymatic activity and isoform composition. In addition, we also analyzed changes in the activity of antioxidant enzymes (SOD, CAT, GPox) to get a comprehensive picture of the antioxidant system. We also evaluated the effects of UV-B on the enzyme sucrose synthase. The overall damage at biochemical level was also assessed by analyzing changes in Hsp70, a protein triggered under stress conditions. The results of this work indicate that the varieties (Giarraffa and Olivastra Seggianese) differ significantly in the use of specific antioxidant defense systems, as well as in the activity and isoform composition of RubisCO. Combined with a different use of sucrose synthase, the overall picture shows that Giarraffa optimized the use of GPox and opted for a targeted choice of RubisCO isoforms, in addition to managing the content of sucrose synthase, thereby saving energy during critical stress points.     

Development of flurbiprofen-loaded nanoparticles with a narrow size distribution using sucrose

Objective: A novel flurbiprofen-loaded nanoemulsion which gave uniform emulsion droplets with a narrow size distribution was previously reported to be prepared using membrane emulsification method. The purpose of this study is to develop a novel flurbiprofen-loaded nanoparticle with a narrow size distribution and improved bioavailability.

Method: The nanoparticle was prepared by solidifying nanoemulsion using sucrose as a carrier via spray drying method. Its physicochemical properties were investigated using SEM, DSC and PXRD. Furthermore, dissolution and bioavailability in rats were evaluated compared to a flurbiprofen-loaded commercial product.

Results: The flurbiprofen-loaded nanoparticles with flurbiprofen/sucrose/surfactant mixture (1/20/2, weight ratio) gave good solidification and no stickiness. They associated with about 70?000-fold improved drug solubility and had a mean size of about 300 nm with a narrow size distribution. Flurbiprofen was present in a changed amorphous state in these nanoparticles. Moreover, the nanoparticles gave significantly shorter T_max, and higher AUC and C_max of the drug compared to the commercial product (p?0.05). In particular, they showed about nine-fold higher AUC of the drug than did the commercial product

Conclusion: These flurbiprofen-loaded nanoparticles prepared with sucrose by the membrane emulsification and spray drying method would be a potential candidate for orally delivering poorly water-soluble flurbiprofen with enhanced bioavailability.     

Development of templated carbon by carbonisation of sucrose–zeolite composite for hydrogen storage

The templated carbons were synthesised by carbonisation of a zeolite–sucrose composite. The effects of carbonisation temperature and dwelling time on the development of pore structure of templated carbon were investigated. Various characterisation techniques were employed to investigate the structural and topographical properties of template precursor as well as synthesised carbons. The highest total surface area of 1033 m²/g and micropore area of 647 m²/g were obtained for carbon synthesised at 750°C with 3 h dwelling time. It was observed that at lower carbonisation temperature or dwelling time, the surface area and pore volume were lower, which may be attributed to incomplete carbonisation of the sucrose. At higher carbonisation temperature or dwelling time, the decrease in surface area and pore volume could be the result of collapse of the pore structure. Maximum 80% micropore area was observed for the templated carbons depending on the synthesis conditions. The hydrogen uptake of the templated carbons was measured by temperature‐programmed desorption at 1 bar pressure and different subzero temperatures. The maximum uptake (0.30 wt%) was obtained at 1 bar and ?100°C for templated carbon, having a surface area of 1033 m²/g, prepared at 750°C with 3 h dwelling time. This templated carbon had the highest total surface area as well as micropore area. Copyright © 2014 John Wiley & Sons, Ltd.     

乙酰水杨酸对番茄果实内各部位糖分含量的影响

采用不同浓度乙酰水杨酸处理番茄果实,对在不同发育阶段果实各部位组织中的糖分含量变化进行了测定,结果表明:在番茄果实不同发育期,果实果皮、胶质胎座和心室隔壁中果糖、葡萄糖和蔗糖含量均表现不同程度的增加,但对果实维管束中糖分含量影响不大,说明乙酰水杨酸具有提高番茄糖分含量的作用。     

蔗糖、乳酸及KH2PO4对乳链菌肽合成的影响

在恒pH、厌氧条件下,研究了蔗糖、乳酸及KH2PO4对L. lactis sp. lactis ATCC11454分批发酵中细胞生长和乳链菌肽合成的影响. 乳链菌肽的合成表现为初级代谢动力学特征. 蔗糖对乳链菌肽的合成具有调控作用,提高蔗糖浓度可以提高细胞浓度及乳链菌肽效价,但过高的蔗糖浓度(>30 g/L)抑制了乳链菌肽的合成. 乳酸作为代谢产物抑制了菌体的生长,同时导致乳链菌肽效价的下降,乳链菌肽对菌体的得率系数YN/X随起始乳酸浓度的增加而减小,表明乳酸对乳链菌肽合成的影响更大. KH2PO4在恒pH条件下对乳链菌肽的合成并没有促进作用.     

蔗糖电解还原制备甘露醇、山梨醇研究

研究了蔗糖水解产物电解还原制甘露醇和山梨醇的工艺,以Raney Ni为催化剂,H2SO4为支持电解质,当总糖浓度为1.0 mol/L,pH=9～10,电流密度为32 mA/cm2,温度为40℃,通电量为理论电量的1.2倍时,总糖的转化率大于95%。     

毛细管电泳电化学检测法测定南瓜中糖类物质

高效毛细管电泳-电化学检测同时测定了南瓜中的蔗糖、麦芽糖、葡萄糖、果糖的含量,考察了实验参数对分离、检测的影响。在最佳实验条件下,以125μm直径的铜圆盘电极为检测电极,检测电位为0．7V（vsAg／AgCl）,在0．08mol／L NaOH溶液中,上述各组分在13min内完全分离。在0．002～2mmol／L的浓度范围内,蔗糖、麦芽糖、葡萄糖和果糖的线性范围均为0．002～2mmol／L。检出限分别为0．72,1．1,0．48,0．67μmol／L（3倍S／N）。峰电流的相对标准偏差RSD分别为2．15％,4．31％,1．22％和0．24％（n=7,c=0．4mmol／L）。该法直接用于南瓜中蔗糖、麦芽糖、葡萄糖和果糖的测定,结果令人满意。     

Biochemical effects of administering shock loads of sucrose to a laboratory-scale anaerobic (UASB) effluent treatment plant

An experimental study was undertaken to determine the effects of administering shock loads of sucrose to a laboratory-scale anaerobic effluent treatment plant (UASB reactor) treating diluted landfill leachate. Administration of shock loads of 10 g l⁻ sucrose caused accumulations of up to 7 g l⁻¹ of l-lactate and the resultant acidity caused the pH value of the reactor effluent to drop from 7.2 to 4.7 which inhibited methanogenesis.Major disturbances in the composition of the biogas also occurred and, under the severest conditions, the biogas contained up to 30% (v/v) hydrogen.     

蔗糖铁中2价铁含量测定的极谱电化学研究

对极谱法测定蔗糖铁中2价铁含量的理想和实际物理模型分别进行了讨论,明确了蔗糖铁极谱行为的非理想特征。通过研究发现了影响测定结果的重要参数包括脉冲电压振幅ΔE,极谱脉冲时间δ和温度T,通过详细试验研究明确了这些参数的具体影响规律。最后,对美国药典中规定的蔗糖铁注射液中2价铁含量测试方法的科学性和合理性进行了分析和探讨,并就新测试方法给出了建议。     

蔗糖溶液浸取-电感耦合等离子体原子发射光谱法测定钢渣中游离氧化钙

提出了一种测定钢渣中游离氧化钙的简便方法。在常温下, 采用200 g/L蔗糖溶液浸取试样30 min, 使游离氧化钙从试样中游离出来, 与其他元素及其他形式的钙分离, 然后将溶液过滤, 选用393.366 nm波长的谱线作为分析线, 在合适的工作条件下用电感耦合等离子体原子发射光谱法测定滤液中钙量, 从而得到样品中游离氧化钙含量。基体对游离氧化钙测定的干扰较小, 共存元素间也基本无干扰。方法被用于测定钢渣样品中游离氧化钙, 测定值与滴定法的测定值相符, 相对标准偏差在0.78%～1.1%之间。