## 6 Biotechnological Uses and Production Potentiality of Carotenoids from Haloarchaea
### Biotechnological Uses of Carotenoids from Haloarchaea
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Publication Number**} & **Publication Date** & **Title** & **International Application Number** \\ \hline WO/2009/042734 & 02.04.2009 & \begin{tabular}{c} Radiation-resistant mutants of a \\ halophilic archaeon and uses thereof \\ \end{tabular} & PCT/US2008/077596 \\ \hline ES2324077 A1 & 29.07.2009 & \begin{tabular}{c} Compuseto a base de membranes \\ cellulares lofizadas \\ \end{tabular} & \\ \hline US 7939220 B2 & 10.05.2011 & Proton-translocating retinal protein & PCT/EP2001/008715 \\ \hline WO2011133907 A2 & 27.10.2011 & \begin{tabular}{c} Methods to increase and harvest desired \\ metabolite production in algae \\ \end{tabular} & PCT/US2011/033637 \\ \hline WO2012169623 & 13.12.2012 & \begin{tabular}{c} Method for producing carotenoid each \\ having 50 carbon atoms \\ \end{tabular} & PCT/JP2012/064817 \\ \hline WO2014045280 A1 & 27.03.2014 & \begin{tabular}{c} Topical halobacteria extract composition \\ for treating radiation skin tissue damage \\ \end{tabular} & PCT/IL2013/050786 \\ \hline WO/2014/045279 & 27.03.2014 & \
\begin{tabular}{c} Halobacteria extracts composition for \\ tumour reduction \\ \end{tabular} & PCT/IL2013/050785 \\ \hline US 20140356854 A1 & 4.10.2014 &
\begin{tabular}{c} Methods and compositions relating to \\ prevalent phosphate decarboxylase \\ \end{tabular} & \\ \hline
07-132096 & 23.05.1995 & Production of C\({}_{50}\) Caroenoid & \\ \hline \hline \end{tabular}  
* In some of the patents, the authors use the term Halobacteria, which was the first name used to identify what it is now call haloarchae (Families _Halobacteriaceae_ and _Haloferacaceae_).  
\end{table} 
Table 2: Patents (last 20 years) related to carotenoids production by haloarchae or its biotechnological uses (as pigments or as antioxidants). The key words used to find out the patents were: bacterioruberin, halobacteria, haloarchae and carotenoids. Data obtained from different websites [129, 130, 131, 132, 133, 134, 135]. controlled. Furthermore, the collection of microbial organisms is sustainable and usually microbial engineering has no negative impact on the environment [58]. Accordingly for all the previous reasons, different species of bacteria, moulds, yeasts and algae have attracted a great interest as alternative biosources for high-scale production of carotenoids [137; 138]. Caroenoid-producing microorganisms have biotechnological attributes proper of microbial cells (fast growth in liquid culture and ability to accumulate or secrete some metabolites). Besides, the use of several molecular biology techniques enables the production of mutant strains able to overproduce carotenoids of interest. For these reasons, microorganisms have become excellent tools to look for new applied processes to obtain biomolecules of high interest in biotechnology and biomedicine and represent the basis of biotechnology-based companies [34]. New research results highlight the possibility of using halophilic microorganisms (mainly halophilic archaea) as natural sources for carotenoids production [19] thanks to the simplicity in increasing carotenoid production by culture conditions and genetic manipulation, and the feasibility of downstream processes of the cells to isolate the carotenoids. The extremely halophilic archaea has unique features making them suitable potential sources for carotenoids production, including: (i) the high-salt tolerance of haloarchae enables their cultivation under non-sterile conditions because high salt concentrations prevent contamination by other organisms. This feature makes cultivation of haloarchae advantageous if compared to cultivation of other microorganisms; (ii) the process to obtain the carotenoids is simple because in lower NaCl concentrations cell lysis is induced and consequently, carotenoids extraction could be conducted directly from the cells without any mechanical operation which is required in case of plants and (iii) the procedures for pigments extraction and purification seem to be simpler than those from other sources.