The Effect of Maturity and Extraction Solvents on Bioactive Compounds and Antioxidant Activity of Mulberry (Morus alba) Fruits and Leaves

Cultivation location, maturity levels, and extraction solvents could affect the bioactive compounds and biological activities of mulberry (Morus alba Linnaeus). The lack of study on Malaysia-grown mulberry causes its underutilization. This study investigated the bioactive compound content and the antioxidant activity of Sabah-grown mulberry at two different maturity stages (fruits: red mature and black fully ripe; leaves: young and mature) extracted using 70% (v/v) methanol, 60% (v/v) ethanol, and 65% (v/v) acetone. Analyses showed that mulberry fruits demonstrated maturity-dependent increment (except UHPLC-DAD quantification), while the leaves revealed maturity-dependent reduction. Principal component analysis (PCA) displayed 65% (v/v) acetone black fully ripe fruits as the best phenolics and antioxidant sources. However, the 60% (v/v) ethanol black fully ripe fruits contained 20.08–68.43% higher total anthocyanins. Meanwhile, the 65% (v/v) acetone and 70% (v/v) methanol red mature fruits were higher in chlorogenic acid (27.53–47.12%) and rutin (31.42–35.92%) than other fruit extracts, respectively. For leaves, 65% (v/v) acetone young leaves were the best phenolics and antioxidant sources. However, the 60% (v/v) ethanol young leaves possessed greater chlorogenic acid (19.56–74.11%) than other leaf extracts. Overall, Malaysia-grown mulberry is rich in phenolics and antioxidants, suggesting its potential application in food and pharmaceutical products.     

液相色谱-串联质谱法测定蔬菜、水果中80种农药残留

建立了同时测定蔬菜、水果中有机磷类、酰胺类、氨基甲酸酯类等80种农药残留的液相色谱-串联质谱(LC-MS/MS)检测方法。样品经乙腈提取,N-丙基乙二胺(PSA)和C18填料分散固相萃取净化,C18柱分离后,在电喷雾正离子化模式下,于三重四极杆质谱仪,动态多反应监测方式测定。结果表明:80种农药的线性范围均超过3个数量级,且r≥0.99;对6种蔬菜、水果样品分别进行0.01、0.05mg/kg2个水平的加标回收实验(n=5),其平均回收率分别为64%～118%和72～108%;RSD分别为3.7%～29.1%和3.4%～27.9%;80种农药的方法检出限(S/N=3)为0.02～3μg/kg。方法快速、准确、灵敏,适用于蔬菜、水果中该80种农药的同时分析。     

介孔氧化铝净化-气相色谱法同时测定蔬菜、水果及茶叶中16种有机磷农药残留

利用气相色谱检测技术,建立了能应用于白菜、生菜、南瓜、洋葱、番茄、白萝卜、苹果、梨及茶叶等不同基质中16种有机磷农药残留的检测方法。样品采用乙酸乙酯提取,经以合成的介孔氧化铝作吸附剂的固相萃取柱净化,DB-1701毛细管柱分离,气相色谱-火焰光度检测器检测。结果表明,蔬菜、水果及茶叶基质中16种有机磷农药在10~2000 μg/L范围内具有良好的线性关系（R²>0.997）;平均回收率为83.2%~103.8%,相对标准偏差为2.0%~9.9%。该方法灵敏度高、准确度高、重复性好,可适用于蔬菜、水果及茶叶基质中16种有机磷残留量的同时测定。     

番茄和黄瓜贮藏保鲜技术研究

分别为保鲜剂贮藏、筐贮、减压贮藏、溶液贮藏、高温处理等方法贮藏番茄５０天后，除减压贮藏方法外，采用其它方法处理的均可使其好果率达８８％以上，商品率达９０％以上，并基本上保持了果实的品质和风味。应用保鲜剂贮藏、减压贮藏方法处理黄瓜，４５天后，好果率达９２％以上，果实品质良好，并且贮藏前后番茄和黄瓜的厉分也无大的变化。     

Thermal Decomposition of Medicinal Plant Raw Materials Based on Principal Component Analysis

Studies on the thermal decomposition of commercial raw plant materials used in medicine were performed. 144 independent samples of plant materials — herbs, leaves,flowers, inflorescences, fruits, roots, rhizomes and barks, collected by Medicinal Plant Works‘Herbapol’, were analyzed. Thermal decomposition was performed using OD-103 Derivatograph. As a result of analysis, it was established, that thermal decomposition of majority of samples proceeds through three stages. The analysis of fruits revealed, that their thermal decomposition proceeds in four stages. In order to obtain a more clear classification of the analyzed plant materials principal component analysis (PCA) was applied. Interpretation of the PCA results allows to state, that samples of raw materials from the same plant species in majority of cases are characterized by similar course of thermal decomposition due to similar chemical composition. In this way the differences in general chemical composition of medicinal plants raw materials can be determined. This revised version was published online in August 2006 with corrections to the Cover Date.     

Interdonato lemon from Nizza di Sicilia (Italy): chemical composition of hexane extract of lemon peel and histochemical investigation

Considering that the determination of authenticity and of the geographical origin of food is a very challenging issue, in this study we studied by means of histological and histochemical analyses the famous Sicilian lemon known as ‘Interdonato Lemon of Messina PGI’. Since the protected geographical indication Interdonato lemon of Messina possesses high organoleptic properties, the composition of the hexane extract of lemon peel was determined by HRGC and HRGC–MS analyses and compared with that of lemon of different cultivars. The results obtained are informative of the oil’s quality and explain the variation of the lemon essential oil composition. Given the fundamental economic implications of any fraud, the aim of this study was to determine a fingerprint able to evaluate the authentication of the geographic origin in such way to prevent frauds in national and international markets.     

Flavonoid Preparations from Taraxacum officinale L. Fruits—A Phytochemical,Antioxidant and Hemostasis Studies

Dandelion (Taraxacum officinale L.) roots, leaves, and flowers have a long history of use in traditional medicine. Compared to the above organs, dandelion fruits are the least known and used. Hence, the present paper was aimed at the phytochemical analysis of T. officinale fruit extract and estimating its antiradical, antiplatelet, and antioxidant properties related to hemostasis. Methanolic extract of fruits (E1), enriched with polyphenols (188 mg gallic acid equivalents (GAE)/g), was successfully separated into cinnamic acids (E2; 448 mg GAE/g) and flavonoids (E3; 377 mg GAE/g) extracts. Flavonoid extract was further divided into four fractions characterized by individual content: A (luteolin fraction; 880 mg GAE/g), B (philonotisflavone fraction; 516 mg GAE/g), C (flavonolignans fraction; 384 mg GAE/g), and D (flavone aglycones fraction; 632 mg GAE/g). High DPPH radical scavenging activity was evaluated for fractions A and B (A > B > Trolox), medium for extracts (Trolox > E3 > E2 > E1), and low for fractions C and D. No simple correlation between polyphenol content and antiradical activity was observed, indicating a significant influence of qualitative factor, including higher anti-oxidative effect of flavonoids with B-ring catechol system compared to hydroxycinnamic acids. No cytotoxic effect on platelets was observed for any dandelion preparation tested. In experiments on plasma and platelets, using several different parameters (lipid peroxidation, protein carbonylation, oxidation of thiols, and platelet adhesion), the highest antioxidant and antiplatelet potential was demonstrated by three fruit preparations–hydroxycinnamic acids extract (E2), flavonoid extract (E3), and luteolin fraction (A). The results of this paper provide new information on dandelion metabolites, as well as their biological potential and possible use concerning cardiovascular diseases.     

总结十年成果 继续开拓创新

在全国贯彻＂科教兴国＂伟大战略任务和实现经济体制、经济增长方式两个根本转变的关键时刻，迎来了国家自然科学基金委员会成立十周年。为了在学科层次上Ｌ贯彻中央精神和纪念我委成立十周年，工程与材料科学部工程热物理学科认真总结了学科十年来资助各类项目的丰硕成果及对国民经济发展的贡献。在此基础上，为了面向未来、抓住机遇、开拓创新，提出厂＂九·五＂期间本学科发展的战略措施和任务，以便为本学科专家申请和评议自然科学基金项目提供参考。     

超高效液相色谱–串联质谱法检测果蔬中的吡氟甲禾灵残留

建立了超高效液相色谱–串联质谱(UPLC–MS/MS)法测定果蔬中吡氟甲禾灵残留的方法。样品以乙腈匀浆提取,并采用Sep-Pak Vac型氨基固相萃取柱净化样品,采用超高效液相色谱柱WATERS ACQUITY C_(18)柱(50mm×2.1 mm,1.7μm)分离,以乙腈–0.1%甲酸水溶液作为淋洗液进行梯度洗脱。吡氟甲禾灵在1.0~50.0 ng/m L范围内线性关系良好,相关系数r~2=0.997 7,加标回收率为84.1%~88.6%,测定结果的相对标准偏差为1.18%~3.58%(n=6)。该方法操作简便,分析快速,提取效率高,重现性好,有实用价值。     

Volatile Compounds of Lemon and Grapefruit IntegroPectin

An HS-SPME GC-MS analysis of the volatile compounds adsorbed at the outer surface of lemon and grapefruit pectins obtained via the hydrodynamic cavitation of industrial waste streams of lemon and grapefruit peels in water suggests important new findings en route to understanding the powerful and broad biological activity of these new pectic materials. In agreement with the ultralow degree of esterification of these pectins, the high amount of highly bioactive α-terpineol and terpinen-4-ol points to limonene (and linalool) decomposition catalyzed by residual citric acid in the citrus waste peel residue of the juice industrial production.