Microorganisms synthesise a wide range of surface-active compounds (SAC), generally called biosurfactants. These compounds are mainly classified according to their molecular weight, physico-chemical properties and mode of action. The low-molecular-weight SACs or biosurfactants reduce the surface tension at the air/water interfaces and the interfacial tension at oil/water interfaces, whereas the high-molecular-weight SACs, also called bioemulsifiers, are more effective in stabilising oil-in-water emulsions. Biosurfactants are attracting much interest due to their potential advantages over their synthetic counterparts in many fields spanning environmental, food, biomedical, and other industrial applications. Their large-scale application and production, however, are currently limited by the high cost of production and by limited understanding of their interactions with cells and with the abiotic environment. In this paper, we review the current knowledge and the latest advances in biosurfactant applications and the biotechnological strategies being developed for improving production processes and future potential.

/pdf/microbial-biosurfactants-production-applications-and-future-1jbia11tup.pdf

Microbial biosurfactants production, applications and future potential

The use and potential commercial application of biosurfactants in the medical field has increased during the past decade. Their antibacterial, antifungal and antiviral activities make them relevant molecules for applications in combating many diseases and as therapeutic agents. In addition, their role as anti-adhesive agents against several pathogens indicates their utility as suitable anti-adhesive coating agents for medical insertional materials leading to a reduction in a large number of hospital infections without the use of synthetic drugs and chemicals. This review looks at medicinal and therapeutic perspectives on biosurfactant applications.

https://repositorium.sdum.uminho.pt/bitstream/1822/5101/1/rodrigues_JAC_2006%5b1%5d.pdf

Biosurfactants: potential applications in medicine

/pdf/biosynthesis-and-mode-of-action-of-lantibiotics-4ckj6jz79p.pdf

Biosynthesis and mode of action of lantibiotics.

https://www.cell.com/trends/biotechnology/pdf/S0167-7799(04)00026-5.pdf

Potential applications of microbial surfactants in biomedical sciences

Nitrile-containing natural products

New antibiotic pumilacidins A, B, C, D, E, F and G were isolated from the culture broth of a strain of Bacillus pumilus. They are cyclic acylheptapeptide composed of a β-hydroxy fatty acid, two L-leucine, two D-leucine, L-glutamic acid, L-aspartic acid and L-isoleucine (or L-valine). Pumilacidin components were inhibitory to herpes simplex virus type 1 and H+, K+-ATPase and demonstrated antiulcer activity in rat.

Pumilacidin, a complex of new antiviral antibiotics. Production, isolation, chemical properties, structure and biological activity.

A strain of Streptoverticillium dnnamoneum produced a peptide antibiotic named lanthiopeptin, which contained four unusual amino acids, erythro-β-hydroxyaspartic acid, meso-lanthionine, threo-β-methyllanthionine and lysinoalanine. Lanthiopeptin showed antiviral activity against herpes simplex virus type 1 KOS strain infection in Vero cells by cytopathic effect reduction assay. The structure of lanthiopeptin is similar to that of ancovenin.

Lanthiopeptin, a new peptide antibiotic. Production, isolation and properties of lanthiopeptin.

Structures of chicamycins A and B have been determined from a series of chemical degradation studies coupled with spectroscopic analysis. Chicamycin A is 2(S),11(R), 11a (S)-1,2,3,10, 11, 11a -hexahydro-2,8-dihydroxy-7,11-dimethoxy-5H-pyrrolo-[2,1-c] [1,4]-benzodiazepin-5-one, and chicamycin B is 2(S), 11a (S)-1,2,3, 11a -tetrahydro-2,8-dihydroxy-7 -methoxy-5H-pyrrolo-[2,1-c][1,4]-benzodiazepin-5-one which is the demethanol form of chicamycin A. The structure of chicamycin B is closely related to that of neothramycin , differing only in the position of a hydroxyl substituent on the pyrrolidine ring.

Chicamycin, a new antitumor antibiotic. II. Structure determination of chicamycins A and B.

A series of structurally related antiviral antibiotics, fluvirucins A1, A2, B1, B2, B3, B4 and B5 have been isolated from the fermentation broths of five unidentified actinomycete isolates. Based on spectroscopic analysis, partial degradation experiments and 13C-enriched acetic acid-fed biosynthetic studies, their structures were elucidated to be 2.6,10-trialkyl-3(or 9)-aminoglycosyl-13-tridecanelactams.

Fluvirucins A1, A2, B1, B2, B3, B4 and B5, new antibiotics active against influenza A virus. II. Structure determination.

Five unidentified actinomycete strains produced a series of novel antiviral antibiotics which have a unique 2,6-dialkyl-10-ethyl-3(or 9)-hydroxy-13-tridecanelactam nucleus substituted with 3-amino-3,6-dideoxy-L-talose or 3-amino-3,6-dideoxy-L-mannose(L-mycosamine). The antibiotic components exhibited potent inhibitory activity against influenza virus type A Victoria strain infection in Madin Darby canine kidney cells by the cytopathic effect reduction assay.

Fluvirucins A1, A2, B1, B2, B3, B4 and B5, new antibiotics active against influenza A virus. I. Production, isolation, chemical properties and biological activities.

Nobuaki Naruse

Papers

Pumilacidin, a complex of new antiviral antibiotics. Production, isolation, chemical properties, structure and biological activity.

Lanthiopeptin, a new peptide antibiotic. Production, isolation and properties of lanthiopeptin.

Chicamycin, a new antitumor antibiotic. II. Structure determination of chicamycins A and B.

Fluvirucins A1, A2, B1, B2, B3, B4 and B5, new antibiotics active against influenza A virus. II. Structure determination.

Fluvirucins A1, A2, B1, B2, B3, B4 and B5, new antibiotics active against influenza A virus. I. Production, isolation, chemical properties and biological activities.