Neri Kimberly D, Devanadera Mark Kevin P, Watanabe Kenshi, Bennett Reuel M, Arafiles Kim Hazel V, Aki Tsunehiro, Dedeles Gina R
The Graduate School, University of Santo Tomas, Manila 1015, Philippines.
Laboratory of Pure and Applied Microbiology, Research Center for the Natural and Applied Sciences, University of Santo Tomas, Manila 1015, Philippines.
Lett Appl Microbiol. 2023 Feb 16;76(2). doi: 10.1093/lambio/ovad022.
Mangroves create an ecological environment for a diverse assemblage of organisms, including marine and mangrove oomycetes. Halophytophthora spp., in particular, are isolated from fallen senescent mangrove leaves. Studies reported on Philippines oomycetes are mostly on their distribution and taxonomy, while fatty acid studies have not yet been fully explored. Recently, oomycetes were reported as efficient producers of various fatty acids; therefore, bioprospecting efforts are aimed at obtaining more industrially important fatty acid compounds for aquaculture, biodiesel production, and human consumption. In this study, 21 isolated oomycetes, identified as Halophytophthora spp., and two type species of Phytopythium, were grown in a broth medium containing peptone, yeast extract, glucose, and 50% seawater and incubated at room temperature for 3 weeks for fatty acid production and identification. Results revealed the presence of various fatty acids, mainly palmitic acid (C16:0), linoleic acid (C18:2n6c), oleic acid (C18:1n9c), cis-11,14,17-eicosatrienoic acid (ETA, C20:3n3), and stearic acid (C18:0), from Halophytophthora and Phytopythium isolates ranging from 2% to 30% total fatty acids. An omega-6 fatty acid, Ƴ-linolenic acid (GLA, C18:3n6), was found in Phytopythium isolates with considerably higher concentrations compared to Halophytophthoras. Further, omega-3 polyunsaturated fatty acid, cis-11,14,17-eicosatrienoic acid (ETA, C20:3n3), was detected on most oomycete isolates.
红树林为包括海洋和红树林卵菌在内的各种生物创造了一个生态环境。特别是盐生疫霉属物种，是从掉落的衰老红树林叶子中分离出来的。关于菲律宾卵菌的研究大多集中在它们的分布和分类上，而脂肪酸研究尚未得到充分探索。最近，有报道称卵菌是各种脂肪酸的高效生产者；因此，生物勘探工作旨在获取更多对水产养殖、生物柴油生产和人类消费具有重要工业价值的脂肪酸化合物。在本研究中，将21株被鉴定为盐生疫霉属的分离卵菌和两种腐霉属模式菌种，在含有蛋白胨、酵母提取物、葡萄糖和50%海水的肉汤培养基中培养，并在室温下孵育3周以进行脂肪酸的生产和鉴定。结果显示存在各种脂肪酸，主要是棕榈酸（C16:0）、亚油酸（C18:2n6c）、油酸（C18:1n9c）、顺式-11,14,17-二十碳三烯酸（ETA，C20:3n3）和硬脂酸（C18:0），盐生疫霉属和腐霉属分离株中的这些脂肪酸占总脂肪酸的2%至30%。在腐霉属分离株中发现了一种ω-6脂肪酸，γ-亚麻酸（GLA，C18:3n6），其浓度比盐生疫霉属分离株高得多。此外，在大多数卵菌分离株中检测到了ω-3多不饱和脂肪酸，顺式-11,14,17-二十碳三烯酸（ETA，C20:3n3）。
