番茄红素调控肠道菌群对健康影响的研究进展北大核心

番茄红素(lycopene)在番茄中含量丰富,具有多种功能活性和营养价值,探讨番茄红素调控肠道菌群对健康的影响有助于深入理解番茄红素的健康效应和作用机制。本文综述了番茄红素的理化性质及其消化、吸收、代谢,重点阐述了番茄红素对宿主肠道菌群种类、数量和代谢产物的影响,以及在番茄红素调控作用下肠道菌群对宿主炎症、心血管疾病、非酒精性脂肪肝和癌症发展的干预作用。该综述为未来番茄营养探索及产品开发提供了思路和方向。     

Lycopene is superior to moringa in improving fertility markers in diet-induced obesity male rats

Obesity is a condition of chronic tissue inflammation and oxidative stress that poses as a risk factor for male infertility. Moringa oleifera oil extract is known to have cholesterol-lowering properties and a potential to treat obesity, while lycopene is a potent antioxidant. We hypothesize that Moringa or lycopene may improve male fertility markers in an animal model of diet-induced obesity. Male Albino rats (n = 60) were randomized to receive regular chow (RC) or high-fat diet (HFD) for 12 weeks (n = 30 each). Animals in each arm were further randomized to receive gavage treatment with corn oil (vehicle), lycopene (10 mg/kg), or Moringa (400 mg/kg) for four weeks starting on week 9 (n = 10 each). Animals were sacrificed at 12 weeks, and blood was collected to assess lipid profile, serum testosterone, and gonadotropin levels. The testes and epididymides were removed for sperm analysis, oxidative stress and inflammatory markers, and histopathological assessment. In comparison to their RC littermates, animals on HFD showed an increase in body weights, serum lipids, testosterone and gonadotrophin levels, testicular oxidative stress and inflammatory markers, as well as sperm abnormalities and disrupted testicular histology. Moringa or lycopene reduced body weight, improved oxidative stress, and male fertility markers in HFD-fed animals with lycopene exhibiting better anti-antioxidant and anti-lipidemic effects. Lycopene is superior to Moringa in improving male fertility parameters, possibly by attenuating oxidative stress.     

Photoisomerization of lycopene during carotenogenesis in mutant C-6D of Scenedesmus obliquus

Mutant C-6D of the unicellular green alga Scenedesmus obliquus has lost the ability to form cyclic carotenoids during heterotrophic growth in the dark. In the dark it accumulates acyclic intermediates, i.e. lycopene, neurosporene and ζ-carotene. The lycopene and two neurosporene forms were identified to be cis-isomers. Upon transfer to light, intermediates decrease and a normal set of carotenoids is synthesized. Inhibition of the cyclization reaction by nicotine reveals a lightinduced isomerization of cis-lycopene to trans-lycopene. Since the spectral characteristics of these two isomers differ drastically the isomerization can be followed in vivo by measuring a light-induced absorbance change. This absorbance change has its maximum at 520 nm and shows fast kinetics under high light intensities reaching a saturation level after about 2 min. Fluence-response curves for this absorbance change were performed for different wavelengths of actinic light. From the linear parts of these curves an action spectrum was caculated showing maxima at 670, 630 and 440 nm originating from chlorophyll and a maximum at shorter wavelengths (400–510 nm) which is interpreted to derive from ζ-carotene. A model for the light regulation of carotenogenesis in mutant C-6D is presented and the relation to the so-called 520-change observed in many plants is discussed.     

发酵法生产制备番茄红素的工艺研究

番茄红素是一种类胡萝卜素，存在于多种果蔬中，具有较好的抗氧化、抗衰老、提高免疫力等功能，被广泛应用于医药、食品、化妆品等领域。然而，传统的提取方法番茄红素产量低、成本高且受制于原料来源，化学合成法存在安全隐患。微生物发酵法因具有工艺简单、生产效率高、生物活性与天然植物提取物一致等优点，逐渐受到关注。基于此，以番茄红素产量为响应值，在单因素实验的基础上利用响应面法优化代谢控制条件，考察正负菌株接种比例、代谢流抑制剂和外源性植物油对番茄红素产量的影响。结果表明，最优条件为三孢布拉氏霉菌负正菌株接种比例6∶1，番茄红素环化酶抑制剂2,6-二甲基吡啶添加量0.09 g·L-1，以3.57 g·L-1大豆油为外源性植物油辅助发酵，在该最优条件下发酵液中的番茄红素产量达1.51 g·L-1，菌体生物量51 g·L-1。研究结果显著提高了发酵菌体生物量，促进了番茄红素的生物合成转化率，为番茄红素的工业化生产提供了理论基础。     

Fungal lycopene: The biotechnology of its production and prospects for its application in medicine

This article deals with the lycopene of mycelial fungi. It pays special attention to its physical and chemical properties, occurrence in nature, biological functions, and the biotechnology of lycopene production. Data are presented concerning the medically important properties of lycopene and the drug Mycolycopene prepared on its basis. Its prospective use in the therapy of prostate cancers is discussed.     

番茄红素对胰腺alpha和beta细胞的差异作用

番茄红素是一种强抗氧化剂,在糖尿病的治疗实验中显示出对机体的保护作用,但是其细胞机制尚不明确。本研究采用不同浓度梯度的番茄红素处理胰腺alpha和beta细胞系,检测细胞的生长、凋亡、周期、活性氧、ATP水平和相关细胞因子的表达变化。结果显示,番茄红素不影响alpha细胞的生长、凋亡、周期、活性氧和ATP水平,但番茄红素可以促进beta细胞的生长、上调其S期比例、降低活性氧水平并提升ATP水平。与此同时,番茄红素可以提升beta细胞tnfα、tgfβ和hif1αmRNA的表达。这些结果表明番茄红素的作用具有细胞特异性,可以活化胰腺beta细胞,为其在糖尿病防治的临床应用提供数据支撑。     

Lycopene cyclization inBlakeslea trispora

Fungi produce and accumulate various carotenoids. Mycelia of the ZygomyceteBlakeslea trispora contained β-carotene and its precursors γ-carotene and lycopene. When strains of opposite sex grew together, the β-carotene concentration increased fourfold, that of γ-carotene remained unchanged, and other intermediates practically disappeared. The inhibitors nicotine, 2-(4-chlorophenylthio)-triethylamine, α-picoline, and imidazole increased the concentrations of lycopene and γ-carotene and decreased those of β-carotene. From our quantitative results, we conclude thatBlakeslea has two pathways for lycopene metabolism, of which other fungi have only one or the other. The main one, two cyclizations from lycopene to β-carotene, is carried out by an enzyme dimer, is stimulated by sexual interaction, and is sensitive to the inhibitors. The other pathway, a cyclization to γ-carotene is not affected by mating or the inhibitors.