茶色素中两个苯骈酚酮类化合物的分离和鉴定

从茶色素中分离得到 2个苯骈卓酚酮类化合物 ,经化学方法与光谱分析鉴定为 7,8,9 三羟基苯骈卓酚酮和 7,8,9 三羟基 4 羟基苯骈卓酚酮。

具有抗癌生物活性的酚酮类化合物的研究近况

一、概述最初从百合科秋水仙属植物秋水仙(Colchicum autumnale L)球茎和种子中提取的秋水仙碱(colchicine)是因治疗痛风病有特效而闻名于世的,后来50年代发现它具有很强的抗癌作用并开始做为早期抗癌剂应用于临床.

新型农抗N2对采后柑橘的保鲜效果研究

【目的】研究新型抗真菌剂-农抗N2对柑橘采后保鲜效果的影响,以期为柑橘采后的防腐保鲜技术提供材料与理论参考。【方法】使用5.77 mg/L农抗N2对采摘后柑橘进行浸泡处理,晾干后使用聚乙烯薄膜进行单果包装,于25℃、相对湿度90%~95%条件下储存60 d,以无菌水浸泡的柑橘为阴性对照,以200 mg/L抑霉唑浸泡处理的柑橘为阳性对照,测定柑橘的腐烂率及失重率,可溶性固形物、可滴定酸、抗坏血酸以及酚类与黄酮类化合物含量,研究农抗N2对柑橘采后的保鲜效果。【结果】农抗N2处理后的柑橘,其失重率与腐烂率显著低于无菌水处理组(CK组),且与抑霉唑处理组无显著性差异;农抗N2处理后的柑橘,其果实可溶性固形物含量在贮存40 d后显著高于CK组;果实可滴定酸与抗坏血酸含量在60 d的贮存期内与CK组无显著性差异;柑橘果皮总酚与黄酮含量在储存50 d后显著高于阴性对照组。【结论】农抗N2能显著降低采后柑橘的失重率以及腐烂率,有效延长采后柑橘的货架期。此外,农抗N2在60 d的贮存期内能显著提高柑橘果实的可溶性固形物含量以及柑橘果皮的酚类与黄酮类化合物含量,有效维持柑橘果实的品质与营养价值。

蜂花粉新鲜度指标的研究进展

蜂花粉含有丰富的营养物质,还含有核酸、黄酮类、酚酸类等具有生物学活性的物质,在增强人体免疫功能、抗氧化、抗肿瘤等方面具有特殊的功效。但是,蜂花粉的品质与新鲜度之间存在密切的关系。本文综述了蜂花粉新鲜度在过氧化氢酶、维生素C、黄酮类和酚酸类化合物等方面的研究进展,为其新鲜度研究及质量控制提供参考。

Comparison of Antioxidant and Antimicrobial Activities of Methanolic Extracts of the Artemisia sp.Recovered by Different Extraction Techniques

The polyphenol content,antioxidant and antimicrobial activities of the extracts obtained by classical, ultrasonic and Soxhlet extractions from dry aerial parts of two Artemisia species(Artemisia vulgaris and Artemisia campestris)were compared.Ultrasound positively affected the yield of extractive substance and the kinetics of extraction,but the extract obtained by the classical extraction showed the highest antioxidant activities and contained higher total contents of phenolic compounds and flavonoids than the extracts obtained by two other extraction techniques.Both flavonoid aglycones(apigenin,quercetin,quercetin 3,3′-dimethyl ether)and flavonoid glycosides(rutin,hyperoside and kaempferol 3-rhamnoside)were identified by thin layer chromatograph(TLC)analysis in the extracts from both species.A.campestris extracts were richer in quercetin than A.vulgaris and its antimicrobial activity was also better than A.vulgaris.Extracts obtained from both species were found to be more effective on the tested yeasts than bacteria.The kinetics of the total extractive substances,such as phenolic,flavonoids and quercetin extraction,was successfully described by the model of unsteady-state diffusion.

Nutritional Profile of Untraditional Colored Wheat Grains and Their Bread Making Utilisation

The aim of this work was to focus on development of the new health benefit food product, bread made from colored wheat flour with a high content of proteins, fibre, β-glucans, phenols, flavonoids. The amount of protein ranged from 9% to 14% in our analyzed set. The highest value had yellow variety of wheat BONA DEA （14%）, at least had red grain of variety FEDERER （9.02%）. Average content of fl-glucans determined by enzymatically ranged from 0.25% （BONA VITA） to 0.67% （ABISSINSKAJA and LUTEUS）. The largest amount of phenolic compounds （134 mg GAE/L） and flavonoids （2.80 mg RE/L） contained sample RU440-6, the lowest sample was IS CORVINUS （87 mg GAE/L）. The highest antioxidant activity was observed in blue varieties of wheat 48M （0.269 mmol TE/L）, while the lowest was determined in a sample of purple ANK 28A （0.083 mmol TE/L）. Data show that there is potential to use purple, blue and red variety of wheat as novel ingredient resources for the development of new innovative products. Assessment of the results we selected two varieties of color wheat （KONINI, RU440-6） in bakery attempt to meet demand for nutritional quality and also have an increased content of healthy components. Overall the most pleasant taste, color and flexibility bread crumb had a loaf of bread prepared from a purple variety KONINI without the addition of β-glucans.

In vitro antioxidant activity of callus culture of carrot （Daucus carom）

Carrot （Daucus carom） is a valuable source of health promoting ingredients such as anthocyanin, carotenes, phenolic compounds etc. These substances are important to man as a source of pharmaceuticals, fragrance, agrochemicals as well as food additives and used for prevention of many chronic diseases. Since these activities may be correlated with the presence of antioxidant compounds, extract of carrot and carrot callus were evaluated for their anthocyanin, flavonoids and total phenolic content as well as total antioxidant activity. Anthocyanin content was measured by spectrophotometric method. Total phenols and flavonoids were analyzed according to the Folin-Ciocalteu method and total antioxidant activity was assessed by ferric reducing/antioxidant power （FRAP） assay. Anthocyanin, flavonoids and total phenolic content were estimated to be 9.36 mg%, 46.96 mg% and 57.01 mg% for callus and 6.82 mg%, 32.96 mg% and 42.69 mg% for carrot, respectively, on fresh weight basis. The total antioxidant activity for the callus and carrot was found to be 51.13 mg, 118.77 mg, 91.08 mg and 140.08 mg equivalent and 79.40 mg, 184.44 mg, 141.43 mg and 217.52 mg equivalent to gallic acid, vitamin C, butylated hydroxyanisole （BHA） and trolox, respectively, when expressed per 100 g on fresh weight basis. The antioxidant activity of fresh carrot was found to be higher compared to its callus.

Interactive effects of soils,local environmental conditions and herbivores on secondary chemicals in tallow tree

Plants produce secondary chemicals that may vary along with latitude due to changing abiotic and biotic stress gradients and local environmental conditions.Teasing apart the individual and combined effects of these different abiotic,such as soil nutrients,and biotic factors,such as soil biota and herbivores,on secondary chemicals is critical for understanding plant responses to changing environments.We conducted an experiment at different latitudes in China,using tallow tree(Triadica sebifera)seedlings sourced from a population at 31°N.These seedlings were cultivated in gardens located at low,middle and high latitudes,with either local soil or soil from the original seed collection site(origin soil).The seedlings were exposed to natural levels of aboveground herbivores or had them excluded.Plant secondary chemicals(both foliar and root),aboveground herbivores and soil characteristics were measured.Results showed that most leaf and root secondary metabolites depended on the interaction of the experimental site and soil type.Leaf and root phenolic and tannin concentrations were higher at the middle latitude site,especially in the origin soil.Root and foliar flavonoid concentrations increased when aboveground herbivores were excluded.Microbial communities depended strongly on soil treatment.The different responses of tannins versus flavonoids suggest that these two chemical classes differ in their responses to the varying abiotic and biotic factors in these sites along latitudes.Taken together,our results emphasize the importance of considering the interactive effects of local environmental conditions,soil properties and herbivory in regulating plant chemical defenses.