Inoculum for a local isolate of oleaginus fungi, Cunninghamella bainieri 2A1 was developed by establishing the inoculum types, age and size for growth, lipid and gamma linolenic acid (GLA) production. Cultivation was carried out in 500 mL shake flask containing 200 mL of nitrogen limiting medium at 30°C and 250 rpm agitation. Direct inoculation of spores into the production cultures gave higher productivity of lipid production 0.71 (g/L/day) than using 24 and 48 vegetative cells cultures which gave only 0.51 and 0.45 (g/L/day), respectively. Besides, production of GLA (5.3 × 10 -2 g/g lipid less biomass) in the cultures which directly inoculated with spores (1 × 10 5 spores/mL) was 23% higher than those produced in the cultures started with vegetative cells. Spore concentration of 1 × 10 3 spores/mL produced pelletal growth in size of 1.04 mm which contain 40% (g/g biomass) lipid and 8.34 × 10 -2 (g/g lipid less biomass).

A new solvent-producing Clostridium has been isolated from soil used in intensive rice cultivation. The 16S rRNA analysis of the isolate indicates that it is closely related to Clostridium acetobutylicum, with a sequence identity of 96%. The new isolate, named C. acetobutylicum YM1, produces biobutanol from multiple carbon sources, including glucose, fructose, xylose, arabinose, glycerol, lactose, cellobiose, mannitol, maltose, galactose, sucrose and mannose. This isolate can also utilize polysaccharides such as starch and carboxylmethyl cellulose (CMC) for the production of biobutanol. The ability of isolate YM1 to produce biobutanol from agro-industrial wastes was also evaluated for rice bran, de-oiled rice bran, palm oil mill effluent and palm kernel cake. The highest concentration of biobutanol (7.27 g/L) was obtained from the fermentation medium containing 2% (w/v) fructose, with a total acetone-butanol-ethanol (ABE) concentration of 10.23 g/L. The ability of isolate YM1 to produce biobutanol from various carbon sources and agro-wastes indicates the promise of the use of this isolate for the production of biobutanol, a renewable energy resource, from readily available renewable feedstocks. 2015 Elsevier Ltd.

Thraustochytrids are marine protists belonging to the class Labyrinthula of the kingdom Chromista. This group of microbes is considered a promising alternative source of high-valued omega-3 oils, especially docosahexaenoic acid (DHA, C22:6. n3), replacing fish oil which is the current major source of DHA and eicosapentaenoic acid (EPA, C20:5. n3). Our new isolate, SW1, was considered to be an Aurantiochytrium based on its morphology, fatty acid profile and molecular phylogenetic analysis. Microscopic observations revealed that SW1 has high similarity to Aurantiochytrium limacinum ATCC MYA-1381 (SR21), possessing spherical vegetative cells which undergo repeated bipartition to form diads, tetrads, octads and zoosporangia that release motile zoospores. When cultivated in four different media, SW1 produced the highest biomass (13.17. g/L) and DHA (3.6. g/L) in a medium composed of glucose, sea salt, monosodium glutamate (MSG) and yeast extract. Visualization of lipid droplet development in SW1 using Sudan Black B dye revealed that lipid droplets enlarge to occupy almost the entire cell volume within 72 to 96. h of cultivation. This strain was also found to be able to utilize various saccharides as carbon source. The results of this study show that Aurantiochytrium sp. SW1 is a potential candidate to be developed as commercial microbial DHA producer. � 2015 Elsevier B.V.

The effects of ammonium tartrate and glucose concentration on biomass, lipid and GLA accumulation in Cunninghamella sp. 2A1 were investigated using Response Surface Methodology (RSM). Cultivation was carried out in 250 mL shake flask containing 100 mL of nitrogen limiting medium (with various combinations of concentration of ammonium tartrate (1-3 g/L) and glucose (30-60 g/L) at 30�C and 250 rpm agitation for 120 h. The concentration of both compounds significantly affected the biomass, lipid and CLA yield (p<0.05), with the production of each of them being represented by quadratic models. Higher concentration of ammonium tartrate and glucose (2.99 and 59.33 g/L, respectively) was required for enhanced biomass production whereas low nitrogen content with excess glucose was otherwise favoured for lipid and GLA production. Ammonium tartrate and glucose concentration at 1 and 43 g/L, respectively were estimated by the model and proven to give the highest lipid production and GLA yield of 31.06 % (g/g biomass) and 4.15 x 10-2(g/g lipid less biomass), respectively.