There is growing interest in the production of microalgae-based high-value by-products as an emerging green biotechnology. However, a cultivation platform for Oocystis sp. has yet to be established. To overcome this limitation, we examined the effect of bacterial culture additions on the growth and production of valuable compounds the Oocystis sp. KNUA044 microalgal strain isolated from a locally adapted region in Korea. This microalgal strain grew only in the presence of a clear supernatant of Sphingomonas sp. KNU100 culture solution and generated 28.57 mg/L/d of biomass productivity. Protein content (43.9 wt%) was approximately two-fold higher than carbohydrate content (29.4 wt%) and lipid content (13.9 wt%). Among monosaccharides, the microalgal strain produced fucose (33 µg/mg and 0.94 mg/L/d), which has not been reported to date. Fatty acid profiling showed high accumulation of polyunsaturated fatty acids (PUFAs; over 60%) compared to saturated (29.4%) and monounsaturated fatty acids (9.9%) under the same culture conditions. Of these PUFAs, the algal strain produced the highest concentration of linolenic acid (C18:3 ω3; 40.2%) in the omega-3 family and generated eicosapentaenoic acid (C20:5 ω3; 6.0%), better known as EPA. Based on these results, we suggest that the application of a Sphingomonas sp. KNU100 strain-dependent culture for cultivation of Oocystis sp. KNUA044 is a promising future bioprocess for increasing algal biomass and high-value bioactive by-products, including fucose and PUFAs such as linolenic acid and EPA.

中文翻译：

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藻类生物量生产和高价值化合物的生产由微藻 Oocystis sp. 的相互作用介导。KNUA044 和细菌鞘氨醇单胞菌 KNU100。

作为一种新兴的绿色生物技术，人们越来越关注以微藻为基础的高价值副产品的生产。然而，卵囊藻的培养平台。尚未确定。为了克服这个限制，我们检查了细菌培养添加物对Oocystis sp. 有价值化合物的生长和产生的影响。从韩国当地适应地区分离的 KNUA044 微藻菌株。这种微藻菌株仅在鞘氨醇单胞菌的清澈上清液存在的情况下生长sp。KNU100 培养液并产生 28.57 mg/L/d 的生物量生产力。蛋白质含量 (43.9 wt%) 比碳水化合物含量 (29.4 wt%) 和脂质含量 (13.9 wt%) 高约两倍。在单糖中，微藻菌株产生岩藻糖（33 µg/mg 和 0.94 mg/L/d），迄今为止尚未见报道。脂肪酸分析表明，在相同培养条件下，与饱和脂肪酸 (29.4%) 和单不饱和脂肪酸 (9.9%) 相比，多不饱和脂肪酸 (PUFAs；超过 60%) 的积累较高。在这些多不饱和脂肪酸中，藻类产生了 omega-3 家族中最高浓度的亚麻酸 (C18:3 ω3; 40.2%)，并产生了二十碳五烯酸 (C20:5 ω3; 6.0%)，即众所周知的 EPA。基于这些结果，我们建议应用鞘氨醇单胞菌sp。KNU100 菌株依赖性培养物，用于培养卵囊藻。KNUA044 是一种很有前途的未来生物工艺，用于增加藻类生物量和高价值生物活性副产品，包括岩藻糖和 PUFA，如亚麻酸和 EPA。