Matos Madalena, Fernandes Mónica A, Costa Inês, Coelho Natacha, Santos Tamára F, Rossetto Veronica, Varela João, Sá-Correia Isabel
iBB-Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisbon, Portugal.
Associate Laboratory i4HB-Institute for Health and Bioeconomy, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal.
J Fungi (Basel). 2025 Mar 17;11(3):228. doi: 10.3390/jof11030228.
The marine oleaginous microalga (formerly ) exhibits a high capacity to thrive in a broad range of environmental conditions, being predominantly utilized as feed in aquaculture. This article reports the characterization of the culturable yeast population present during the scale-up process of cultivation at Necton S.A. facilities, from 5 L flasks until tubular photobioreactors. The 146 yeast isolates obtained, molecularly identified based on D1/D2 and ITS nucleotide sequences, belong to the species , , , , , , and . The yeast abundance was found to increase throughout upscaling stages. The yeast populations isolated from microalgal cultures and water samples share phylogenetically close isolates, indicating a possible common source. The impressive high percentage of red yeasts isolated (90%) is consistent with the recognized role of carotenoid pigments in yeast photoprotection. Sixty yeast isolates were tested for lipid (Nile Red staining) and biosurfactant (oil drop dispersion and emulsification index) production. Results revealed that these capacities are common features. Microbial lipids and biosurfactants have promising biotechnological applications. Moreover, biosurfactants can fulfill various physiological roles and provide advantages in natural environments contributing to the promising use of yeasts as probiotics in microalgae production.
海洋产油微藻（原称 ）具有在广泛环境条件下茁壮生长的高能力，主要用作水产养殖的饲料。本文报道了在Necton S.A.设施中，从5升烧瓶到管式光生物反应器的 培养放大过程中可培养酵母种群的特征。通过基于D1/D2和ITS核苷酸序列进行分子鉴定得到的146株酵母分离株，属于 、 、 、 、 、 和 物种。发现酵母丰度在放大阶段不断增加。从微藻培养物和水样中分离出的酵母种群具有系统发育上相近的分离株，表明可能有共同来源。分离出的红酵母比例高达90%，这与类胡萝卜素色素在酵母光保护中的公认作用一致。对60株酵母分离株进行了脂质（尼罗红染色）和生物表面活性剂（油滴分散和乳化指数）生产测试。结果表明这些能力是常见特征。微生物脂质和生物表面活性剂具有很有前景的生物技术应用。此外，生物表面活性剂可以发挥各种生理作用，并在自然环境中提供优势，这有助于将酵母作为益生菌用于微藻生产。
