TECHNOLOGY FOCUS - BIOLOGY - Preferred Alga: The alga is selected from Bacillariophyceae, Chlorophyceae, Cyanophyceae, Xanthophyceae, Chrysophyceae, Chlorella, Crypthecodinium, Schizocytrium, Nannochloropsis, Ulkenia, Dunaliella, Cyclotella, Navicula, Nitzschia, Cyclotella, Phaeodactylum, and Thraustochytrid genera (preferably Chlorella genus or Chlorella protothecoides species).    TECHNOLOGY FOCUS - BIOTECHNOLOGY - Recombinant Method (disclosed): Preparation of recombinant oleaginous alga involves transforming an alga cell with a nucleic acid fragment including a nucleotide sequence encoding a sugar metabolizing enzyme and/or a sugar transporter protein. Preferred Alga: The oleaginous alga further comprises heterologous genes expressing sugar metabolizing enzymes that are lacking in a wild-type form of the oleaginous alga. The recombinant oleaginous alga further comprises a nucleotide sequence expressing an RNAi construct complementary to all or a portion of the nucleotide sequence either of a gene expressing ADP glucose pyrophosphorylase in order to decrease starch synthesis by the alga, or of a gene expressing pyruvate decarboxylase in order to decrease ethanol synthesis by the alga, or of a gene expressing pyruvate formate lyase to reduce formate synthesis by the alga, or of a gene expressing acetyl CoA carboxylase (ACCase) in order to increase fatty acid synthesis by the alga; and an expression vector for overexpressing diacylglycerol acyl transferase (DGAT) and caleosin and/or oleosin in order to increase fatty acid synthesis and accumulation in the alga. Preferred Method: The biofuel precursors are extracted by mixing a portion of the algal culture with an oil-extracting solvent to obtain a solvent-algae mixture, partitioning the solvent-algae mixture to obtain a solvent-biofuel precursor fraction and viable extracted algae, and returning the viable extracted algae to the algal culture. Preferred Components: The heterologous genes express sugar metabolizing enzymes that are lacking in a wild-type form of the oleaginous alga. The natural saccharide is a cellulosic or hemicellulosic sugar or a monosaccharide derived from it. The natural saccharide is sucrose and the sugar metabolizing enzyme is an invertase. The sugar metabolizing enzymes are selected from enzymes capable of metabolizing the saccharides glucose, rhamnose, arabinose, galactose, mannose, fucose and xylose. The saccharide is arabinose and the sugar metabolizing enzymes comprise 1-arabinose reductase, 1-arabitol 4-dehydrogenase, and 1-xylulose reductase; or is rhamnose and the sugar metabolizing enzymes comprise L-rhamnose isomerase, rhamnulokinase, and rhamnulose-1-phosphate aldolase; or is galactose and the sugar metabolizing enzymes comprise uridine diphosphate (UDP) glucose-hexose-1-phosphate uridyltranserase and UDP glucose-hexose-1-phosphate uridylyltranserase; or is xylose and the sugar metabolizing enzymes comprise xylose isomerase, xylose reductase, xylitol dehydrogenase, and xylulokinase; or is mannose and the sugar metabolizing enzymes comprise hexokinase, mannokinase, ATP-dependent fructokinase, and mannose-6-phosphate isomerase. The heterologous genes express sugar transporters that are lacking in a wild-type form of the oleaginous alga. The sugar transporter is selected from STP1, HUP1, HUP2, and HUP3 transporters. The promoter is apsaD promoter or an actin promoter. The heterologous genes comprise promoters that are operatively linked to a gene expressing a sugar metabolizing enzyme or a sugar transporter. The heterologous genes comprise a Chlorella kessleri hup1 gene that is operatively linked to a Chlamydomonas psaD promoter and rbcs2 terminator. EXAMPLE - No suitable example given.