幾十年以來，綠藻一直被用于商業生產，包括生產人類消費的健康食品，動物飼料和水產餌料，著色劑、化妝品及其它制劑等。如今，我們使用的一些綠藻產品包括從微藻生物質中提取的次生代謝物，其中最廣為人知的是蝦青素及β-胡蘿卜素這2種類胡羅卜素，它們已經被用于著色劑及健康制劑。許多綠藻產生的高價值代謝產物具有不同的用途，例如用來生產抗氧化劑、類胡羅卜素、多元不飽和脂肪酸、維生素及抗癌抗菌藥物。許多研究顯示，當藻類處于營養缺乏、光照、溫度、鹽度及pH脅迫時會產生上述的次生代謝物；少數研究表明當微藻處于最適生長條件下時也可以檢測到這些次生代謝物。但是，我們還不清楚如何優化培養條件從而提高每種次生代謝物的產量以及不同脅迫條件下對微藻次生代謝物的影響。一些綠藻在硫脅迫時具有顯著的產氫能力，這是當前世界藻類學研究的熱點之一，而且這些研究已集中在模式生物衣藻上，但是其它綠藻也具有產氫能力。目前，有關微藻同步產氫及其它次生代謝物的研究很少。本研究的目的是對比誘導微藻生產次生代謝物及產氫的脅迫條件；列舉具有生產高價值次生代謝物，還能在厭氧缺硫條件下產氫的野生綠藻的種類；同時文章還綜述了目前已商業化生產的微藻種類。通過分析這些信息為篩選微藻，實現利用微藻產氫及產次生代謝物相結合提供基礎。
Green microalgae for several decades have been produced for commercial exploitation, with applications ranging from health food for human consumption, aquaculture and animal feed, to coloring agents, cosmetics and others. Several products from green algae which are used today consist of secondary metabolites that can be extracted from the algal biomass. The best known examples are the carotenoids astaxanthin and β-carotene, which are used as coloring agents and for health-promoting purposes. Many species of green algae are able to produce valuable metabolites for different uses; examples are antioxidants, several different carotenoids, polyunsaturated fatty acids, vitamins, anticancer and antiviral drugs. In many cases, these substances are secondary metabolites that are produced when the algae are exposed to stress conditions linked to nutrient deprivation, light intensity, temperature, salinity and pH. In other cases, the metabolites have been detected in algae grown under optimal conditions, and little is known about optimization of the production of each product, or the effects of stress conditions on their production. Some green algae have shown the ability to produce significant amounts of hydrogen gas during sulfur deprivation, a process which is currently studied extensively worldwide. At the moment, the majority of research in this field has focused on the model organism, Chlamydomonas reinhardtii, but other species of green algae also have this ability. Currently there is little information available regarding the possibility for producing hydrogen and other valuable metabolites in the same process. This study aims to explore which stress conditions are known to induce the production of different valuable products in comparison to stress reactions leading to hydrogen production. Wild type species of green microalgae with known ability to produce high amounts of certain valuable metabolites are listed and linked to species with ability to produce hydrogen during general anaerobic conditions, and during sulfur deprivation. Species used today for commercial purposes are also described. This information is analyzed in order to form a basis for selection of wild type species for a future multi-step process, where hydrogen production from solar energy is combined with the production of valuable metabolites and other commercial uses of the algal biomass.
（Skjånes K, Rebours C, Lindblad P Potential for green microalgae to produce hydrogen, pharmaceuticals and other high value products in a combined process. Crit Rev Biotechnol. 2013, 33(2):172-215.）
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