@article { ISI:000244292900012, title = {Purification by silica gel chromatography using dialysis tubing and characterization of sophorolipids produced from Candida bombicola grown on glucose and arachidonic acid}, journal = {Biotechnology Letters}, volume = {29}, number = {2}, year = {2007}, month = {FEB}, pages = {267-272}, publisher = {SPRINGER}, type = {Article}, address = {VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS}, abstract = {

The yeast Candida bombicola (ATCC 22214) grown on primary carbon source glucose (100 g l(-1)) and secondary carbon, arachidonic acid (2 g l(-1)) produced mixture of sophorolipids up to 1.44 g l(-1). The crude product was a heterogeneous mixture of sophorolipids, which are glycolipids of sophorose linked to the fatty acid through glycosidic bond between omega and omega-1 carbon of arachidonic acid. The derived sophorolipids were isolated by silica gel chromatography using dialysis tubing. The purified sophorolipids were characterized by ESI-MS and FT-IR. Acid hydrolysis of the resolved sophorolipids were characterized by ESI-MS for the presence of 20-hydroxy-5Z,8Z,11Z,14Z-eicosatetraenoic acid (20-HETE) and 19-hydroxy-5Z,8Z,11Z,14Z-eico-satetraenoic acid (19-HETE), compounds of pronounced pharmaceutical importance.

}, keywords = {19-HETE, 20-HETE, arachidonic acid, electrospray soft ionization mass spectroscopy, silica gel chromatography, Sophorolipid}, issn = {0141-5492}, doi = {10.1007/s10529-006-9221-5}, author = {Shah, Sachin and Prabhune, Asmita} } @article { ISI:000262377000003, title = {In situ synthesis of ligand reduced/capped silver nanoparticles and the effect of temperature and ligand structure on the size of silver nanoparticles}, journal = {Journal of Chemical Sciences}, volume = {120}, number = {6}, year = {2008}, note = {International Conference on Molecules and Materials - New Directions, Bangalore, INDIA, DEC 04, 2008}, month = {JAN}, pages = {515-520}, publisher = {INDIAN ACAD SCIENCES}, type = {Article, Proceedings Paper}, address = {C V RAMAN AVENUE, SADASHIVANAGAR, P B \#8005, BANGALORE 560 080, INDIA}, abstract = {

We report in situ synthesis of silver nanoparticles using biosurfactants called sophorolipids as reducing and capping agents. We further study the effect of temperature and the structure of sophorolipid on the size of silver nanoparticles obtained. The silver nanoparticles were characterized by UV-visible, transmission electron microscope (TEM) and light scattering (DLS) analysis techniques.

}, keywords = {dynamic light scattering, Nucleation and growth, silver nanoparticles, Sophorolipid}, issn = {0974-3626}, doi = {10.1007/s12039-008-0080-6}, author = {Kasture, M. B. and Patel, P. and Prabhune, Asmita and Ramana, C. V. and Kulkarni, A. A. and Bhagavatula L. V. Prasad} } @article { ISI:000290493000005, title = {Differentiation-inducing ability of sophorolipids of oleic and linoleic acids using a glioma cell line}, journal = {Biotechnology Journal}, volume = {6}, number = {5, SI}, year = {2011}, month = {MAY}, pages = {509-512}, publisher = {WILEY-BLACKWELL}, address = {COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA}, abstract = {

Sophorolipids are biosurfactants produced by non-pathogenic yeasts. They show structural similarity with the membrane components of mammalian cells, i.e., glycosphingolipids and gangliosides, which are involved in processes such as signaling, oncogenesis, and differentiation. Sophorolipids have been reported to induce differentiation in several leukemic cell lines, cell death via apoptosis in a human liver cancer cell line, and necrosis in a pancreatic adenocarcinoma cell line. Here we report, for the first time, the effects of precursor fatty acids and sophorolipids of oleic and linoleic acids in pure acidic and crude forms on LN-229, a glioma cell line. In response to different sophorolipid forms, various morphological changes were observed, such as formation of long thread-like extensions arising from the ends of the cells, cell alignment, cell elongation and bundle formation in a dose-dependent manner. In this study we present the morphological evidence of the potential of sophorolipids as differentiation inducers.

}, keywords = {Differentiation, Glioma, LN-229, Sophorolipid}, issn = {1860-6768}, doi = {10.1002/biot.201000345}, author = {Joshi-Navare, Kasturi and Shiras, Anjali and Prabhune, Asmita} } @article { ISI:000306933400046, title = {Segmented flow synthesis of Ag nanoparticles in spiral microreactor: role of continuous and disperzsed phase}, journal = {Chemical Engineering Journal}, volume = {192}, year = {2012}, month = {JUN}, pages = {357-368}, publisher = {ELSEVIER SCIENCE SA}, address = {PO BOX 564, 1001 LAUSANNE, SWITZERLAND}, abstract = {

This work focuses on understanding the effect of segmented flow on the nanoparticle size distribution in a unidirectionally expanding spiral microreactor, where secondary flows are prevalent in the absence of segmentation. Stearic acid sophorolipid reduced/capped Ag NPs were synthesized in the aqueous phase and air or kerosene was used as inert phases for creating the gas-liquid and liquid-liquid segmented flow, respectively. While, in one case the reactant phase is in the form of dispersed phase slugs, in the other case it is in the form of continuous phase, each exhibiting a different behavior. The slug sizes and the slip velocity, both of which govern the nature of internal mixing in the reactant phase slug controlled the nanoparticle size distribution. This observation was consistent for both, gas-liquid and liquid-liquid segmented flows. The micromixer having smaller orifice diameter yielded smaller slugs and also a narrow particle size distribution. In general, the particle sizes were much smaller for gas-liquid flow rather than for liquid-liquid flow. Because of the unidirectionally expanding spiral geometry of the channel, at any given condition, unsteady behavior of slugs due to continuously varying radius of curvature results in variation in the slip velocity along the length of microchannel. This effect was seen to further narrow the particle size distribution than alone by the segmented flow. (C) 2012 Elsevier B.V. All rights reserved.

}, keywords = {Ag nanoparticles, Segmented flow synthesis, Sophorolipid, Spiral microreactor}, issn = {1385-8947}, doi = {10.1016/j.cej.2012.02.084}, author = {Kumar, D. V. Ravi and Bhagavatula L. V. Prasad and Kulkarni, Amol A.} } @article { ISI:000340537000016, title = {New yeast isolate Pichia caribbica synthesizes xylolipid biosurfactant with enhanced functionality}, journal = {European Journal of Lipid Science and Technology}, volume = {116}, number = {8}, year = {2014}, month = {AUG}, pages = {1070-1079}, publisher = {WILEY-BLACKWELL}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

Sophorolipids (SL) belong to a class of glycolipidic biosurfactants suitable for a wide range of applications. The structural diversity in SL gives rise to variation in physicochemical and biological properties. To achieve the less explored head group diversity in sophorolipid structure, a new xylose fermenting yeast Pichia caribbica has been employed for biosurfactant production. The media and fermentation parameters have been optimized to achieve maximum yield of 7.48 g/L. The physicochemical properties of the xylolipid biosurfactant have been assessed. It reduced the surface tension of distilled water from 70 to 35.9 mN/m with the low critical micellar concentration (CMC) 1.0 mg/L as compared to typical SL (reported CMC range 40-100 mg/L). Structural characterization was done using FTIR and HR-MS to identify the structure. 17-L-[(beta-D-xylopyranosyl)-oxy]-Delta 9-heptadecanoic acid correlated to m/z 415 majorly constituted the product. Control experiment was performed in which glucose was provided as the hydrophilic carbon. This product was also subjected to HR-MS analysis to determine its chemical nature and found to be different from xylolipid. Presence of xylose as head group was anticipated to give altered physicochemical and biological activities and indeed a low CMC value and better inhibitory action was demonstrated against Staphylococcus aureus. Practical applications: Sophorolipids produced by microbial sources have several advantageous properties over commercial petroleum-based surfactants including biodegradability, environmentally friendly nature, and low toxicity. Here, we have attempted to modify the hydrophilic head group by incorporating xylose in place of glucose. This molecule will also behave differently in response to different stimuli. Stimuli-responsive surfactants are a class of compounds with applications in stabilization of emulsions, suspensions or foams, drug encapsulation and delivery, hard-surface cleaning, personal care applications.

}, keywords = {Antibacterial action, Critical micelle concentration, Pichia caribbica, Sophorolipid, Xylolipid}, issn = {1438-7697}, doi = {10.1002/ejlt.201300363}, author = {Joshi-Navare, Kasturi and Singh, Pradeep Kumar and Prabhune, Asmita} } @article {44242, title = {pH dependent sophorolipid assemblies and their influence on gelation of silk fibroin protein}, journal = {Materials Chemistry and Physics}, volume = {203}, year = {2018}, month = {JAN }, pages = {9-16}, type = {Article}, abstract = {

Sophorolipid (SL), a bio-derived surfactant is an excellent gelling agent for natural fibrous protein, silk fibroin (SF) leading to potential biomedical applications. Interaction of SF with SL has been shown to accelerate the formation of hydrogel with the rate being dependent on the form of SL used. Here, we examine the effect of pH on SL-SF interaction and gel formation by employing rheology, fluorescence spectroscopy, SANS and NMR. The results indicate that the size of SL assemblies decrease as pH increases from acidic to alkaline and significantly impacts the association of SL and SF. The association of SF and SL is mainly via hydrophobic interactions, with the SL molecules forming bead like structures along the SF chain. The increased charge on the acidic form of SL at higher pH results in greater repulsion between acidic SL molecules, which are bound to the hydrophobic sites of SF, leading to rapid chain unfolding and subsequent gelation. (C) 2017 Elsevier B.V. All rights reserved.

}, keywords = {Assemblies, Nuclear magnetic resonance spectroscopy, pH, Silk fibroin, Small angle neutron scattering, Sophorolipid}, issn = {0254-0584}, doi = {10.1016/j.matchemphys.2017.09.045}, author = {Dubey, Parul and Kumar, Sugam and Ravindranathan, Sapna and Vasudevan, Sahana and Aswal, Vinod K. and Rajamohanan, Pattuparambil R. and Nisal, Anuya and Prabhune, Asmita} } @article {44606, title = {Photophysical studies on curcumin-sophorolipid nanostructures: applications in quorum quenching and imaging}, journal = {Royal Society Open Science}, volume = {5}, year = {2018}, month = {FEB}, pages = {170865}, abstract = {

Sophorolipid biosurfactants are biodegradable, less toxic and FDA approved. The purified acidic form of sophorolipid is stimuli-responsive with self-assembling properties and used for solubilizing hydrophobic drugs. This study encapsulated curcumin (CU) with acidic sophorolipid (ASL) micelles and analysed using photophysical studies like UV-visible spectroscopy, photoluminescence (PL) spectroscopy and timecorrelated single photon counting (TCSPC). TEM images have revealed ellipsoid micelles of approximately 100nm size and were confirmed by dynamic light scattering. The bacterial fluorescence uptake studies showed the uptake of formed CUASL nanostructures into both Gram-positive and Gram-negative bacteria. They also showed quorum quenching activity against Pseudomonas aeruginosa. The results have demonstrated this system has potential theranostic applications.

}, keywords = {curcumin, photophysical, Quorum quenching, Sophorolipid}, issn = {2054-5703}, doi = {10.1098/rsos.170865}, author = {Vasudevan, Sahana and Prabhune, Asmita A.} } @article {46150, title = {Formulation and evaluation of wound healing activity of sophorolipid-sericin gel in wistar rats}, journal = {Pharmacognosy Magazine}, volume = {15}, year = {2019}, month = {APR}, pages = {123-127}, type = {Article}, abstract = {

Sericin is a useful by-product of silk processing and is resistant to oxidation and ultraviolet and can absorb and release moisture easily. Sericin has biological activities such as antibacterial, antioxidant, and tyrosinase inhibition. Sophorolipids are microbial extracellular glycolipids produced by resting cells of Candida bombicola. Sophorolipids show excellent skin compatibility and also have antibacterial property. In this study, we have developed a novel formulation consisting of sericin and sophorolipid with calcium alginate as a binding agent. Since both the ingredients are biocompatible and biodegradable, the formulation was tested for wound healing in Wistar rats. A commercial ointment povidone was used as control. The animal group, treated with sericin and sophorolipid cream, showed fast contraction, rapid closure, and healing when compared with control and commercial ointment. These observations were validated with histopathological studies where more fibroblast proliferation, angiogenesis, and keratinization were observed. This is a green, cost-effective formulation for fast wound healing.

}, keywords = {Biocompatibility, formulation, sericin, Sophorolipid, wound Healing}, issn = {0973-1296}, doi = {10.4103/pm.pm_392_18}, author = {More, V. Snehal and Koratkar, Santosh S. and Kadam, Navnath and Agawane, Sachin and Prabhune, Asmita} }