Biosurfactants Future Trends and Challenges - Biosurfactants: Research Trends and Applications - page 314

of the importance of the marine resource for such novel compounds and their envi-
ronmental credentials are expected to support both search and potential industrial
application of biosurfactants in many industrial applications.
l iPoPePtiDes
Surfactin has very interesting surfactant properties. Potential medical applications are
related to anti-inflammatory, antiviral, antibiotic, and anti-adhesive activities. However,
the economics are not competitive due to poor yields and the requirement for expensive
and complex substrates. Portilla-Rivera et al. (2009) have postulated that biosurfactant
costs can be as low as $0.50/L from molasses sugarcane. Low-cost purification methods
are also needed as downstream costs can account for 60% of the cost (Mukherjee et al.,
2006). Purity of the product is also a major consideration; 98% pure surfactin is sold for
$10 per mg but can be reduced to $2-$4/kg for tank cleaning or oil recovery applica-
tions (Bognolo, 1999). Although more information is available concerning biosynthe-
sis of surfactin, there is still a lack of information regarding its secretion, metabolic
route, primary cell metabolism, and physicochemical properties of the biosurfactant.
Research is thus required to enhance the applications of the surfactant. New forms of
surfactin and other lipopeptides could also become available.
t rehalose B iosurfaCtants
Trehalose lipids have been extensively studied over the past several decades and thus
there now has been a significant amount of research regarding their production, chemical
structures and properties. Despite their favorable physicochemical and biological activi-
ties, which determine their potential applications in environmental and industrial bio-
technologies, these affordable biosurfactants have not been commercialized extensively.
This is mainly due to the fact that trehalose lipids are mostly cell-bound and are produced
from nonrenewable carbon sources. There is still a lack of research on the development
of efficient bioprocesses, using low-cost and renewable resources and the optimization
of the culture conditions, including cost-effective recovery processes. Although that dif-
ferent attractive aspects of trehalose lipids have been recently documented, such as their
biomedical and therapeutic properties, future fundamental research should be focused
toward the development of novel genetically engineered hyperproducing strains coupled
with economization of the biosurfactant production process. The efficient combination
of these options could open up perspectives for higher yields and successful large-scale
economically profitable production of these unique biomolecules.
APPLICATIONS OF BIOSURFACTANTS
The market for biosurfactants was 2210 million USD in 2011 and will grow from
2011 to 2018 at a rate of 3.5% (Transparency Market Research) (Sekhon et al., 2012).
Producers of soaps, toothpastes, washing powders, detergents are increasingly
becoming more aware and interested in biosurfactants due to their excellent proper-
ties of biodegradability, low toxicity, and surface activity. Some of the applications
are detailed in Table 12.1 and in the following sections.