Biosurfactant production was screened in four lactobacilli strains. The highest biosurfactant production (excreted and cell-bound biosurfactants) was achieved with Lactobacillus paracasei ssp. paracasei A20, a strain isolated from a Portuguese dairy plant, with a decrease in the surface tension of 6.4？mN？m？1 and 22.0？mN？m？1, respectively. Biosurfactant production by this strain was evaluated under different culture broth compositions. The use of different nitrogen sources revealed that yeast extract is essential for bacterial growth, while peptone is crucial for biosurfactant synthesis. For biosurfactant production, the use of peptone and meat extract yielded a higher production when compared to the standard medium, with a surface tension reduction of 24.5？mN？m？1. Furthermore, experiments were also conducted in a reactor with pH and temperature control. Biomass and biosurfactant production in bioreactor was higher comparing with the experiments conducted in shake flaks. The optimization procedure adopted in the current work was found to improve the biosurfactant production and opened new perspectives for the use of L. paracasei ssp. paracasei A20 as a promising biosurfactant-producer. 1. Introduction Biosurfactants are surface-active compounds synthesized by microorganisms with pronounced surface and emulsifying activities [1, 2]. Several properties and physiological functions in the producer organisms have been described for different groups of biosurfactants, that include solubility of hydrophobic compounds, heavy metal binding, bacterial pathogenesis, cell adhesion and aggregation, quorum sensing, and biofilm formation [2, 3]. Bacteria are the main group of biosurfactant-producing microorganisms, although they are also produced by some yeasts and filamentous fungi [4]. These compounds can be synthesized by microorganisms growing on water-immiscible hydrocarbons, as well as on water-soluble compounds such as glucose, sucrose, glycerol, or ethanol, and can be excreted or remain attached to the cell wall [5]. Diversity existing among the biosurfactant-producing microorganisms suggests that their production represents an important survival strategy and appears to have evolved in an independent, yet parallel fashion [6, 7]. A number of studies have reported the potential of lactobacilli as biosurfactant-producers [8–16]. Biosurfactants isolated from several lactobacilli have been characterized as multicomponent mixtures, consisting of protein and polysaccharides [13, 14, 17, 18]; in other cases, the surface active compounds were identified as glycolipids
References
[1]
L. R. Rodrigues, I. M. Banat, J. A. Teixeira, and R. Oliveira, “Biosurfactants: potential applications in medicine,” Journal of Antimicrobial Chemotherapy, vol. 57, no. 4, pp. 609–618, 2006.
[2]
J. D. Van Hamme, A. Singh, and O. P. Ward, “Physiological aspects. Part 1 in a series of papers devoted to surfactants in microbiology and biotechnology,” Biotechnology Advances, vol. 24, no. 6, pp. 604–620, 2006.
[3]
P. Singh and S. S. Cameotra, “Potential applications of microbial surfactants in biomedical sciences,” Trends in Biotechnology, vol. 22, no. 3, pp. 142–146, 2004.
[4]
J. D. Desai and I. M. Banat, “Microbial production of surfactants and their commercial potential,” Microbiology and Molecular Biology Reviews, vol. 61, no. 1, pp. 47–64, 1997.
[5]
S. Mukherjee, P. Das, and R. Sen, “Towards commercial production of microbial surfactants,” Trends in Biotechnology, vol. 24, no. 11, pp. 509–515, 2006.
[6]
A. A. Bodour, K. P. Drees, and R. M. Maier, “Distribution of biosurfactant-producing bacteria in undisturbed and contaminated arid southwestern soils,” Applied and Environmental Microbiology, vol. 69, no. 6, pp. 3280–3287, 2003.
[7]
O. Langer, O. Palme, V. Wray, H. Tokuda, and S. Lang, “Production and modification of bioactive biosurfactants,” Process Biochemistry, vol. 41, no. 10, pp. 2138–2145, 2006.
[8]
H. J. Busscher, C. G. Van Hoogmoed, G. I. Geertsema-Doornbusch, M. Van Der Kuijl-Booij, and H. C. Van Der Mei, “Streptococcus thermophilus and its biosurfactants inhibit adhesion by Candida spp. on silicone rubber,” Applied and Environmental Microbiology, vol. 63, no. 10, pp. 3810–3817, 1997.
[9]
E. J. Gudi？a, V. Rocha, J. A. Teixeira, and L. R. Rodrigues, “Antimicrobial and antiadhesive properties of a biosurfactant isolated from Lactobacillus paracasei ssp. paracasei A20,” Letters in Applied Microbiology, vol. 50, no. 4, pp. 419–424, 2010.
[10]
E. J. Gudi？a, J. A. Teixeira, and L. R. Rodrigues, “Isolation and functional characterization of a biosurfactant produced by Lactobacillus paracasei,” Colloids and Surfaces B, vol. 76, no. 1, pp. 298–304, 2010.
[11]
L. R. Rodrigues, A. Moldes, J. A. Teixeira, and R. Oliveira, “Kinetic study of fermentative biosurfactant production by Lactobacillus strains,” Biochemical Engineering Journal, vol. 28, no. 2, pp. 109–116, 2006.
[12]
C. G. Van Hoogmoed, M. Van Der Kuijl-Booij, H. C. Van Der Mei, and H. J. Busscher, “Inhibition of Streptococcus mutans NS adhesion to glass with and without a salivary conditioning film by biosurfactant-releasing Streptococcus mitis strains,” Applied and Environmental Microbiology, vol. 66, no. 2, pp. 659–663, 2000.
[13]
M. M. Velraeds, H. C. Van der Mei, G. Reid, and H. J. Busscher, “Physicochemical and biochemical characterization of biosurfactants released by Lactobacillus strains,” Colloids and Surfaces B, vol. 8, no. 1-2, pp. 51–61, 1996.
[14]
M. M. Velraeds, H. C. Van der Mei, G. Reid, and H. J. Busscher, “Inhibition of initial adhesion of uropathogenic Enterococcus faecalis by biosurfactants from Lactobacillus isolates,” Applied and Environmental Microbiology, vol. 62, no. 6, pp. 1958–1963, 1996.
[15]
R. Thavasi, S. Jayalakshmi, and I. M. Banat, “Application of biosurfactant produced from peanut oil cake by Lactobacillus delbrueckii in biodegradation of crude oil,” Bioresource Technology, vol. 102, no. 3, pp. 3366–3372, 2011.
[16]
P. Saravanakumari and K. Mani, “Structural characterization of a novel xylolipid biosurfactant from Lactococcus lactis and analysis of antibacterial activity against multi-drug resistant pathogens,” Bioresource Technology, vol. 101, no. 22, pp. 8851–8854, 2010.
[17]
L. R. Rodrigues, J. A. Teixeira, H. C. van der Mei, and R. Oliveira, “Isolation and partial characterization of a biosurfactant produced by Streptococcus thermophilus A,” Colloids and Surfaces B, vol. 53, no. 1, pp. 105–112, 2006.
[18]
L. R. Rodrigues, J. A. Teixeira, H. C. van der Mei, and R. Oliveira, “Physicochemical and functional characterization of a biosurfactant produced by Lactococcus lactis 53,” Colloids and Surfaces B, vol. 49, no. 1, pp. 79–86, 2006.
[19]
M. Pacwa-Plociniczak, G. A. Plaza, Z. Piotrowska-Seget, and S. S. Cameotra, “Environmental applications of biosurfactants: recent advances,” International Journal of Molecular Sciences, vol. 12, pp. 633–654, 2011.
[20]
R. S. Makkar and S. S. Cameotra, “An update on the use of unconventional substrates for biosurfactant production and their new applications,” Applied Microbiology and Biotechnology, vol. 58, no. 4, pp. 428–434, 2002.
[21]
F. F. Barros, A. N. Ponezi, and G. M. Pastore, “Production of biosurfactant by Bacillus subtilis LB5a on a pilot scale using cassava wastewater as substrate,” Journal of Industrial Microbiology and Biotechnology, vol. 35, no. 9, pp. 1071–1078, 2008.
[22]
G. Bustos, N. de la Torre, A. B. Moldes, J. M. Cruz, and J. M. Domínguez, “Revalorization of hemicellulosic trimming vine shoots hydrolyzates trough continuous production of lactic acid and biosurfactants by L. pentosus,” Journal of Food Engineering, vol. 78, no. 2, pp. 405–412, 2007.
[23]
S. Fox and G. Bala, “Production of surfactant from Bacillus subtilis ATCC 21332 using potato substrates,” Bioresource Technology, vol. 75, no. 3, pp. 235–240, 2000.
[24]
S. Joshi, C. Bharucha, S. Jha, S. Yadav, A. Nerurkar, and A. J. Desai, “Biosurfactant production using molasses and whey under thermophilic conditions,” Bioresource Technology, vol. 99, no. 1, pp. 195–199, 2008.
[25]
A. B. Moldes, A. M. Torrado, M. T. Barral, and J. M. Dominguez, “Evaluation of biosurfactant production from various agricultural residues by Lactobacillus pentosus,” Journal of Agricultural and Food Chemistry, vol. 55, no. 11, pp. 4481–4486, 2007.
[26]
O. M. P. Rivera, A. B. Moldes, A. M. Torrado, and J. M. Domínguez, “Lactic acid and biosurfactants production from hydrolyzed distilled grape marc,” Process Biochemistry, vol. 42, no. 6, pp. 1010–1020, 2007.
[27]
L. R. Rodrigues, J. A. Teixeira, and R. Oliveira, “Low-cost fermentative medium for biosurfactant production by probiotic bacteria,” Biochemical Engineering Journal, vol. 32, no. 3, pp. 135–142, 2006.
[28]
L. R. Rodrigues and J. A. Teixeira, “Biosurfactants production from cheese whey,” in Advances in Cheese Whey Utilization, M. E. Cerdán, M. González-Siso, and M. Becerra, Eds., pp. 81–104, Transworld Research Network, 2008.
[29]
J. C. DeMan, M. Rogosa, and M. E. Sharpe, “A medium for the cultivation of lactobacilli,” Journal of Applied Bacteriology, vol. 23, pp. 130–135, 1960.
[30]
G. L. Miller, “Use of dinitrosalicylic acid reagent for determination of reducing sugar,” Analytical Chemistry, vol. 31, no. 3, pp. 426–428, 1959.
[31]
S. Kim, E. Lim, S. Lee, J. Lee, and T. Lee, “Purification and characterization of biosurfactants from Nocardia sp. L-417,” Biotechnology and Applied Biochemistry, vol. 31, no. 3, pp. 249–253, 2000.
[32]
G. Georgiou, S. C. Lin, and M. M. Sharma, “Surface-active compounds from microorganisms,” Biotechnology, vol. 10, no. 1, pp. 60–65, 1992.
[33]
H. J. Busscher, T. Neu, and H. C. Van der Mei, “Biosurfactant production by thermophilic dairy streptococci,” Applied Microbiology and Biotechnology, vol. 41, no. 1, pp. 4–7, 1994.
[34]
T. Morishita, Y. Deguchi, and M. Yajima, “Multiple nutritional requirements of lactobacilli: genetic lesions affecting amino acid biosynthetic pathways,” Journal of Bacteriology, vol. 148, no. 1, pp. 64–71, 1981.
[35]
M. Abouseoud, R. Maachi, A. Amrane, S. Boudergua, and A. Nabi, “Evaluation of different carbon and nitrogen sources in production of biosurfactant by Pseudomonas fluorescens,” Desalination, vol. 223, no. 1–3, pp. 143–151, 2008.
[36]
L. R. Rodrigues, J. A. Teixeira, R. Oliveira, and H. C. Van der Mei, “Response surface optimization of the medium components for the production of biosurfactants by probiotic bacteria,” Process Biochemistry, vol. 41, no. 1, pp. 1–10, 2006.
[37]
P. Das, S. Mukherjee, and R. Sen, “Substrate dependent production of extracellular biosurfactant by a marine bacterium,” Bioresource Technology, vol. 100, no. 2, pp. 1015–1019, 2009.
