Table olive (Olea europaea L.) fruit is widely used in the food industry due to its excellent nutritional and health values. The objective of the present research was to determine aroma profiles by hydrodistillation and GC/MS of the autochthonous Meski and two introduced table olives (Picholine and Manzanella) treated with two traditional Tunisian processes. Independent of the processing method, the olive fruit had significant cultivar‐dependent differences. The volatile compounds of the treated products were affected by processing: total terpenes increased, while aldehydes decreased and new aroma profiles emerged with large variations in the rate of appearances of the different aroma compounds. Principal component analysis showed that fruit quality is strongly affected by its endogenous specificity and by the processing method used.

Food analysis is important for the evaluation of the nutritional value and quality of fresh and processed products, and for monitoring food additives and other toxic contaminants. Sample preparation, such as extraction, concentration and isolation of analytes, greatly influences the reliable and accurate analysis of food. Solid-phase microextraction (SPME) is a new sample preparation technique using a fused-silica fiber that is coated on the outside with an appropriate stationary phase. Analyte in the sample is directly extracted to the fiber coating. The SPME technique can be used routinely in combination with gas chromatography (GC), GC-mass spectrometry (GC-MS), high-performance liquid chromatography (HPLC) or LC-MS. Furthermore, another SPME technique known as in-tube SPME has also been developed for combination with LC or LC-MS using an open tubular fused-silica capillary column as an SPME device instead of SPME fiber. These methods using SPME techniques save preparation time, solvent purchase and disposal costs, and can improve the detection limits. This review summarizes the SPME techniques for coupling with various analytical instruments and the applications of these techniques to food analysis.

白酒是我国传统而又独具特色的蒸馏酒，也是世界六大蒸馏酒之一。白酒中含有多种风味化合物，包括酯类、醇类、酮类、醛类、酸类、萜烯类、含硫化合物等，这些风味物质虽然含量很低，但风味物质的组成及含量对白酒口感和香味的贡献很大，是形成不同酒类风格的重要因素。该文主要对近年来白酒中风味物质种类、风味物质分析前处理技术、风味物质测定方法及功能性风味成分相关研究进行了综述，以期为白酒中风味物质分析与鉴定提供一定的参考。

【目的】研究欧李果实发育过程中的挥发性成分与含量变化,揭示果实香气的香型转化特征,明确参与挥发物合成的主要代谢途径,为探讨果实香气代谢机制及品质育种提供数据支持。【方法】以‘燕山1号’欧李为试材,采用顶空固相微萃取-气相色谱仪-质谱联用技术（HS-SPME-GC-MS）,自坐果25 d开始,每隔10 d对果实挥发性成分进行测定。利用解卷积系统（AMDIS）与NIST11质谱库以及保留指数（RI）对挥发性成分进行鉴定,内标法确定挥发物含量,进一步明确果实香气品质与香型转化特征以及不同挥发物类型合成的主要代谢途径。【结果】发育期内共检测到140种挥发物,幼果期明显多于其他时期,成分复杂;绿果期挥发物生成速率显著升高,含量增加。酯、萜类是主要挥发物类型,含量占90%以上。青香型挥发物在幼果期至着色期内含量丰富,商熟期内显著降低;果香型挥发物自商熟期逐渐增加,花香型挥发物在完熟期内显著增加。OAVs表明幼果期至绿熟期花香强度高,是主要香气特征,着色期开始果香强度随发育期逐渐增加,完熟期后果香与花香强度接近,是成熟果实的典型香气特征。幼果期挥发物代谢途径复杂,产生的挥发物类型丰富,其中参与萜类合成主要为MEP和MVP代谢途径,参与醛、醇、酯类合成主要为脂肪族和氨基酸代谢途径;绿熟期至商熟期萜类物质代谢程度与参与酯类合成的氨基酸代谢程度明显降低,不饱和脂肪酸代谢程度明显增加;完熟期不饱和脂肪酸代谢活跃度降低,参与酯类合成的饱和脂肪酸和氨基酸代谢途径以及参与单萜合成的脂肪酸β-氧化途径与脱辅基类胡萝卜素裂解途径增强,形成了大量支链酯类和芳香酯类以及环状单萜,对于典型成熟果实香气的形成具有重要作用。【结论】欧李果实发育过程挥发物变化明显,合成代谢途径具有明显更替。发育早期产生的挥发物有助于果实发育和环境适应;绿熟期以不饱和脂肪酸为底物的己酯、己烯酯类合成途径明显加强,挥发物逐渐积累;着色期果实快速生长,挥发物合成具有滞后性,代谢途径明显转化;完熟期参与支链酯、芳香酯、环状单萜的合成代谢途径明显增强,与成熟果实香气明显相关。典型果实香气主要形成于完熟期,稍晚于生理成熟期,适当延迟采收有助于果实芳香品质的形成与保留。

研究薯蔓多糖(PSPV)对动物的非特异性免疫和特异性体液免疫调节作用。采用碳粒廓清实验研究PSPV对正常和免疫低下小鼠的非特异性免疫功能;血清溶血素测定法研究PSPV的特异性体液免疫功能。结果表明:PSPV可提高正常和免疫低下小鼠的廓清指数K和呑噬指数α,800mg／kg剂量的PSPV可显著提高小鼠血清的血清溶血素HC50。结论:PSPV具有促进单核巨噬细胞系统吞噬功能的作用,可增强小鼠的非特异性免疫功能,同时也可极显著地增强小鼠的特异性体液免疫功能。

为了明确不同品种甘薯茎叶的营养与功能成分组成,本试验系统比较了58个不同品种甘薯茎叶中的粗蛋白、粗脂肪、膳食纤维、维生素、多酚类物质、黄酮类物质含量及抗氧化活性。结果表明,甘薯茎叶富含粗蛋白(9.35~38.45 g·100 g^-1 DW)、粗脂肪(1.36~12.30 g·100 g^-1 DW)、总膳食纤维(35.30~45.0 g·100 g^-1 DW)、维生素C(1.47~131.64 mg·100 g^-1 DW)、β-胡萝卜素(6.75~59.35 mg·100 g^-1 DW)及维生素E(0.39~23.30 mg·100 g^-1 DW);湛薯01-2品种甘薯茎叶中总酚含量(21.39 g CAE·100 g^-1 DW)及抗氧化活性(40.28 g TE·100 g^-1 DW)最高。抗氧化活性与营养成分之间的相关性分析结果表明,甘薯茎叶中主要的抗氧化活性物质为多酚类物质(R²=0.748)。本研究为甘薯茎叶的合理开发利用提供了一定的指导。

The molecular mechanisms associated with secondary cell wall (SCW) deposition in sorghum remain largely uncharacterized. Here, we employed untargeted metabolomics and large-scale transcriptomics to correlate changes in SCW deposition with variation in global gene expression profiles and metabolite abundance along an elongating internode of sorghum, with a major focus on lignin and phenolic metabolism. To gain deeper insight into the metabolic and transcriptional changes associated with pathway perturbations, a bmr6 mutant [with reduced cinnamyl alcohol dehydrogenase (CAD) activity] was analyzed. In the wild type, internode development was accompanied by an increase in the content of oligolignols, p-hydroxybenzaldehyde, hydroxycinnamate esters, and flavonoid glucosides, including tricin derivatives. We further identified modules of genes whose expression pattern correlated with SCW deposition and the accumulation of these target metabolites. Reduced CAD activity resulted in the accumulation of hexosylated forms of hydroxycinnamates (and their derivatives), hydroxycinnamaldehydes, and benzenoids. The expression of genes belonging to one specific module in our co-expression analysis correlated with the differential accumulation of these compounds and contributed to explaining this metabolic phenotype. Metabolomics and transcriptomics data further suggested that CAD perturbation activates distinct detoxification routes in sorghum internodes. Our systems biology approach provides a landscape of the metabolic and transcriptional changes associated with internode development and with reduced CAD activity in sorghum.