Polar Lipids Composition,Antioxidant and Anti-Inflammatory Activities of the Atlantic Red Seaweed Grateloupia turuturu

Grateloupia turuturu Yamada, 1941, is a red seaweed widely used for food in Japan and Korea which was recorded on the Atlantic Coast of Europe about twenty years ago. This seaweed presents eicosapentaenoic acid (EPA) and other polyunsaturated fatty acids (PUFAs) in its lipid fraction, a feature that sparked the interest on its potential applications. In seaweeds, PUFAs are mostly esterified to polar lipids, emerging as healthy phytochemicals. However, to date, these biomolecules are still unknown for G. turuturu. The present work aimed to identify the polar lipid profile of G. turuturu, using modern lipidomics approaches based on high performance liquid chromatography coupled to high resolution mass spectrometry (LC–MS) and gas chromatography coupled to mass spectrometry (GC–MS). The health benefits of polar lipids were identified by health lipid indices and the assessment of antioxidant and anti-inflammatory activities. The polar lipids profile identified from G. turuturu included 205 lipid species distributed over glycolipids, phospholipids, betaine lipids and phosphosphingolipids, which featured a high number of lipid species with EPA and PUFAs. The nutritional value of G. turuturu has been shown by its protein content, fatty acyl composition and health lipid indices, thus confirming G. turuturu as an alternative source of protein and lipids. Some of the lipid species assigned were associated to biological activity, as polar lipid extracts showed antioxidant activity evidenced by free radical scavenging potential for the 2,2′-azino-bis-3-ethyl benzothiazoline-6-sulfonic acid (ABTS^●+) radical (IC₅₀ ca. 130.4 μg mL⁻¹) and for the 2,2-diphenyl-1-picrylhydrazyl (DPPH^●) radical (IC₂₅ ca. 129.1 μg mL⁻¹) and anti-inflammatory activity by inhibition of the COX-2 enzyme (IC₅₀ ca. 33 µg mL⁻¹). Both antioxidant and anti-inflammatory activities were detected using a low concentration of extracts. This integrative approach contributes to increase the knowledge of G. turuturu as a species capable of providing nutrients and bioactive molecules with potential applications in the nutraceutical, pharmaceutical and cosmeceutical industries.     

Seaweed Blends as a Valuable Source of Polyunsaturated and Healthy Fats for Nutritional and Food Applications

Seaweeds are considered healthy and sustainable food. Although their consumption is modest in Western countries, the demand for seaweed in food markets is increasing in Europe. Each seaweed species has unique nutritional and functional features. The preparation of blends, obtained by mixing several seaweeds species, allows the obtaining of maximum benefits and ingredients with single characteristics. In this work, five seaweed blends, commercially available and produced under organic conditions in Europe, were characterized. The proximal composition included contents of ash (20.28–28.68% DW), proteins (17.79–26.61% DW), lipids (0.55–1.50% DW), and total carbohydrates (39.47–47.37% DW). Fatty acid profiles were determined by gas chromatography–mass spectrometry (GC–MS), allowing quantification of healthy fatty acids, namely n-3 and n-6 polyunsaturated fatty acids (PUFA), and calculation of lipid quality indices. Each blend showed a characteristic PUFA content in the lipid pool (35.77–49.43% of total fatty acids) and the content in essential and healthy n-3 PUFA is highlighted. The atherogenicity (0.54–0.72) and thrombogenicity (0.23–0.45) indices evidenced a good nutritional value of lipid fractions. As nutritional and environmentally attractive products, the consumption of the studied seaweed blends can contribute to a healthy lifestyle.     

脂质组学技术在家畜精液质量评价和体外保存研究中的应用研究进展

精液质量评价是公畜繁殖力评定的重要手段之一。随着组学技术的快速发展，研究人员可以获得精子细胞高通量的基因、转录本、蛋白和代谢物等信息，对于精液质量评价以及相关的辅助生殖技术研究具有重要意义。最近，研究人员尝试采用脂质组学技术探讨影响哺乳动物精子细胞受精能力的因素。脂质组学（lipidomics）主要是利用高通量技术研究细胞、组织或生物体内的脂类成分和分布等基本生物学特征，在对脂类进行精确定量的基础上，探讨脂类多样性与细胞代谢调控和相应生物学功能的关系。作为蛋白质和核酸的下游产物，脂类可以更直接地反映组织细胞的实时生理状态。精子细胞质膜富含各种脂类，这些脂类对精子细胞的结构和功能具有重要影响。此外，通过脂质组学研究可以获得一些潜在的标记物用于家畜精液质量评价。目前，脂质组学已经应用于精子细胞脂肪酸研究。然而，虽然脂质组学研究发展迅速，但该方法仍存在一定的局限性，主要表现为样品脂类提取技术流程没有统一标准，导致对同一个结果产生不同的解释，因此，脂质组学技术仍有较大的提升空间。作者系统介绍了家畜精子的脂质组基本特征，并总结了脂质组学在精液质量评价和体外保存研究领域的发展现状，同时对其未来发展趋势进行了展望。