translation.en: They take the sediment itself, they extract the oil from it, and from that they can produce compounds which turn out to be very specific to particular microbial groups.
translation.zh: 他们取沉淀物本身，从其中提取油， 通过油，又能制作混合物， 结果发现这种混合物适于某种特定的微生物种群。