**Author details**

**Table 7.** Comparison between lipid percentages (%) produced by eight algal species using hexane/ether (1:1, v/v) and

The obtained results illustrated in Table 8 revealed that the solvent mixture hexane/ether were not the most suitable system for lipid biodiesel extraction from algae because these solvents were unable to extract polar lipids. On the contrary chloroform/methanol system extracted greater percentage of lipid (non-polar and polar lipids) and gave place to higher biodiesel yields by transesterification. The lowest biodiesel production was observed in the red seaweed *J. rubens* (0.25%) followed in ascending order by *Gelidium latifolium* (1.3%), *Galaxaura oblonga‐ ta* (2.06%) and A. taxiformis (3.64%). While the green macroalga Ulva lactuca and the brown seaweed Colpomenia sinuosa produced comparable biodiesel percentages (3.8 and 3.1%, respectively), the greatest yield of biodiesel was achieved by the green microalgae *D. splen‐ dida* (8.75%) followed in descending order by the cyanbacterium *S. platensis* (7.5%) as illustrated in Table 2. Using chloroform/methanol (2:1, v/v) solvent system, we are able to produce not only biodiesel in large percentage but also a sediment containing glycerin and pigments. The produced biodiesel have slightly alkaline pH values ranging 7.5–8.5 in all preparations. Our results concerning the green microalga *D. splendida* (produced 12.5% lipids) agreed with those obtained by Hossain and Salleh [20] who reported that the green filamentous alga Oedogoni‐

chloroform/methanol (2:1, v/v) extraction systems [21].

18 Biofuels - Status and Perspective

um sp produced higher lipid.

multiple range test.

**3. Conclusion**

**Biodiesel colour Sediment % Biodiesel% Lipid % Algal sp.** Light brown ± 0.05 → 4.2a 0.25±0.01 4.4±0.12 *Jania rubens*

Light green 0.44±0.0 3.8±0.12 4.2±0.1 *Ulva lactuca* Yellow 0.31±0.05 3.1±0.05 3.5±0.05 *Colpomenia sinuosa* Colourless 3.75±0.08 8.75±0.24 12.5±0.23 *Dictyochloropsis splendida*

Light green 1.66±0.06 7.5±0.30 9.2±0.25 *Spirulina platensis*

solvent system Chloroform/methanol (2:1, v/v) (Afify et al., 2010).

**0.1786 0.3314 0.3261 LSD**

Each value is presented as mean of triplet treatments, LSD: Least different significantly at P ≤ 0.05 according to Duncan's

**Table 8.** Total lipid, biodiesel, sediments percentage and biodiesel colour of different algal species using the extraction

From this chapter we conclude that non-edible biomass can be used as a suitable and cheap feedstock for producing biodiesel. Most of non-edible biomass has a considerable amount of

Light green 0.08±0.0 2.06±0.02 2.5±0.09 *Galaxaura oblongata* Yellow 1.6±0.01 1.3±0.0 3.0±0.0 *Gelidium latifolium* Dark green 0.40±0.01 ± 0.10 → 3.64c 4.1±0.08 *Asporagopsis taxiformis* Emad A. Shalaby

Address all correspondence to: dremad2009@yahoo.com

Biochemistry Department, Faculty of Agriculture, Cairo University, Giza, Egypt
