Biomedical and therapeutic applications of biosurfactants

During the last years, several applications of biosurfactants with medical purposes have been reported. Biosurfactants are considered relevant molecules for applications in combating many diseases and as therapeutic agents due to their antibacterial, antifungal and antiviral activities. Furthermore, their role as anti-adhesive agents against several pathogens illustrate their utility as suitable anti-adhesive coating agents for medical insertional materials leading to a reduction of a large number of hospital infections without the use of synthetic drugs and chemicals. Biomedical and therapeutic perspectives of biosurfactants applications are presented and discussed in this chapter

Production of a cellulosic substrate susceptible to enzymatic hydrolysis from prehydrolyzed barley husks

An effective process for the chemical-biotechnological utilization of barley husks is reported. A first treatment with sulfuric acid (prehydrolysis) allowed the solubilization of hemicelluloses to give xylose-containing liquors (suitable to make fermentation media for xylitol production) and a solid phase containing cellulose and lignin. The solid residues from prehydrolysis were treated with NaOH in order to increase their cellulase digestibility. In the alkaline treatments, the effects of temperature (in the range, 50-130ºC), reaction time (10-60 min) and NaOH concentration (3-10 weight percent of solution) on the composition of solid residues were assessed by means of an experimental plan with factorial structure. The cellulose content increased with temperature and NaOH concentration, whereas the duration of treatments was not influential within the range tested. The treated samples showed high susceptibility toward the enzymatic hydrolysis with cellulases, leading to almost quantitative glucose yields under selected operational conditions

Production of a cellulosic substrate susceptible to enzymatic hydrolysis from prehydrolyzed barley husks

An effective process for the chemical-biotechnological utilization of barley husks is reported. A first treatment with sulfuric acid (prehydrolysis) allowed the solubilization of hemicelluloses to give xylose-containing liquors (suitable to make fermentation media for xylitol production) and a solid phase containing cellulose and lignin. The solid residues from prehydrolysis were treated with NaOH in order to increase their cellulase digestibility. In the alkaline treatments, the effects of temperature (in the range, 50-130ºC), reaction time (10-60 min) and NaOH concentration (3-10 weight percent of solution) on the composition of solid residues were assessed by means of an experimental plan with factorial structure. The cellulose content increased with temperature and NaOH concentration, whereas the duration of treatments was not influential within the range tested. The treated samples showed high susceptibility toward the enzymatic hydrolysis with cellulases, leading to almost quantitative glucose yields under selected operational conditions

Alkaline hydrolysis of ferulic acid and p-coumaric acid from the solid residue obtained after prehydrolysis of prunings of vine shoots: effect of extractant and pH

This work deals with the chemical-biotechnological processing of trimming vineshoots wastes for the solubilization of hydroxycinnamic acids

Bioactivity of glycolipopeptide cell-bound biosurfactants against skin pathogens

"Available online 21 November 2017"The antimicrobial and anti-adhesive activities of the cell-bound biosurfactants, produced by Lactobacillus pentosus (PEB), characterized as glycolipopeptide macromolecules, were evaluated against several microorganisms present in the skin microflora, envisaging its potential use as a natural ingredient in cosmetic and personal care formulations. Their performance was compared with another cell-bound biosurfactants also characterized as glycolipopeptides produced by Lactobacillus paracasei (PAB). At concentrations of 50 mg/mL, the PEB showed an important antimicrobial activity against Pseudomonas aeruginosa (85% when extracted with phosphate buffer (PB) and 100% when extracted with phosphate buffer saline (PBS)), Streptococcus agalactiae (100% for both extracts), Staphylococcus aureus (67% when extracted with PBS and 100% when extracted with PB), Escherichia coli (72% when extracted with PB and 89% when extracted with PBS), Streptococcus pyogenes (about 85% for both extracts) and Candida albicans (around 70% for both extracts), comparable with that obtained for the PAB. However, at lower concentrations the PAB exhibited in general higher antimicrobial activities. Biosurfactants produced by both microorganisms also showed significant anti-adhesive properties against all the microorganisms under study, except for E. coli and C. albicans (less than 30%). Overall, these cell-bound biosurfactants could be used as potential antimicrobial and anti-adhesive agents in cosmetic and pharmaceutical formulations.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, COMPETE 2020 (POCI01-0145-FEDER-006684), the Project MultiBiorefinery − Multipurposestrategies for broadband agro-forest and fisheries byproducts valorisation: a step forward for a truly integrated biorefinery (POCI-01-0145-FEDER-016403) and the project RECI/BBBEBI/0179/2012 (FCOMP-01-0124-FEDER-027462), as well as X. Vecino post-doctoral grant (SFRH/BPD/101476/2014). Also, L. Rodríguez-López acknowledges to the Spanish Ministry of Education, Culture and Sport for her pre-doctoral fellowship (FPU15/00205).info:eu-repo/semantics/publishedVersio

Characterization of cultivated fungi isolated from grape marc wastes through the use of amplified rDNA restriction analysis and sequencing

Microbial assessment of grape marc wastes, the residual solid by-product of the wine-industry, was performed by identifying phylogenetically the fungal culturable diversity in order to evaluate environmental and disposal safety issues and to discuss ecological considerations of applications on agricultural land. Fungal spores in grape marc were estimated to 4.7x10(6) per g dry weight. Fifty six fungal isolates were classified into eight operational taxonomic units (OTUs) following amplified ribosomal DNA restriction analysis (ARDRA) and colony morphology. Based on 18S rRNA gene and 5.8S rRNA gene-ITS sequencing, the isolates representing OTUs #1, #2, #3, and #4, which comprised 44.6%, 26.8%, 12.5%, and 5.3%, respectively, of the number of the total isolates, were identified as Aspergillus fumigatus, Bionectria ochroleuca, Haematonectria haematococca, and Trichosporon mycotoxinivorans. The isolates of OTU#5 demonstrated high phylogenetic affinity with Penicillium spp., while members of OTUs #6 and #7 were closer linked with Geotrichum candidum var. citri-aurantii and Mycocladus corymbifer, respectively (95.4 and 97.9% similarities in respect to their 5.8S rRNA gene-ITS sequences). The OTU#8 with a single isolate was related with Aspergillus strains. It appears that most of the fungal isolates are associated with the initial raw material. Despite the fact that some of the species identified may potentially act as pathogens, measures such as the avoidance of maintaining large and unprocessed quantities of grape marc wastes in premises without adequate aeration, together with its suitable biological treatment (e.g., composting) prior to any agriculture-related application, could eliminate any pertinent health risks