In this work, we isolated and selected oleaginous yeasts from rock field soils from two National Parks in Brazil (Caparaó and Serra dos Órgãos) with the potential to accumulate oil from xylose, the main pentose sugar found in lignocellulosic biomass. From the 126 isolates, two were selected based on their lipid contents. They were taxonomically identified as Papiliotrema laurentii (UFV-1 and UFV-2). Of the two, P. laurentii UFV-1 was selected as the best lipid producer. Under unoptimized conditions, lipid production by P. laurentii UFV-1 was higher in glucose than in xylose. To improve its lipid production from xylose, we applied response surface methodology (RSM) with a face-centered central composite design (CCF). We evaluated the effects of agitation rate, initial cell biomass (OD₆₀₀), carbon/nitrogen ratio (C/N ratio) and pH on lipid production. P. laurentii UFV-1 recorded the highest lipid content, 63.5% (w/w) of the cell dry mass, under the following conditions: C/N ratio = 100:1, pH value = 7.0, initial OD₆₀₀ = 0.8 and agitation = 300 rpm. Under these optimized conditions, biomass, lipid titer and volumetric lipid productivity were 9.31 g/L, 5.90 g/L and 0.082 g/L.h, respectively. Additionally, we determined the fatty acid composition of P. laurentii UFV-1 as follows: C14:0 (0.5%), C16:0 (28.4–29.4%), C16:1 (0.2%), C18:0 (9.5–11%), C18:1 (58.6–60.5%), and C20:0 (0.7–0.8%). Based on this composition, the predicted properties of biodiesel showed that P. laurentii UFV-1 oil is suitable for use as feedstock in biodiesel production.

在这项工作中，我们从巴西两个国家公园（Caparaó和Serra dos Órgãos）的岩石田地土壤中分离并选择了含油酵母，这些酵母具有从木糖中积累油的潜力，木糖是木质纤维素生物质中发现的主要戊糖。从 126 个分离株中，根据其脂质含量选择了两个。它们在分类学上被确定为Papiliotrema laurentii（UFV-1 和 UFV-2）。在这两者中，P. laurentii UFV-1 被选为最好的脂质生产者。在未优化的条件下，P. laurentii 的脂质生产UFV-1 在葡萄糖中高于木糖。为了提高木糖的脂质产量，我们应用了响应面方法 (RSM) 和面心中心复合设计 (CCF)。我们评估了搅拌速率、初始细胞生物量 (OD ₆₀₀ )、碳/氮比 ( C / N比) 和 pH 值对脂质生产的影响。在以下条件下，P. laurentii UFV-1 记录的脂质含量最高，为细胞干重的 63.5% (w/w)：C / N比 = 100:1，pH 值 = 7.0，初始 OD ₆₀₀ = 0.8 和搅拌 = 300 rpm。在这些优化条件下，生物量、脂质滴度和体积脂质生产率分别为 9.31 g/L、5.90 g/L 和 0.082 g/Lh。此外，我们确定了P. laurentii UFV-1的脂肪酸组成如下：C14:0 (0.5%)、C16:0 (28.4–29.4%)、C16:1 (0.2%)、C18:0 (9.5– 11%)、C18:1 (58.6–60.5%) 和 C20:0 (0.7–0.8%)。基于这种成分，生物柴油的预测特性表明P. laurentii UFV-1 油适合用作生物柴油生产的原料。