Fig 1 - uploaded by Richard Ashby
Content may be subject to copyright.
![Structures of sophorolipids. The 17-L-[(2 0-O-b-glucopyranosyl-b-D-glucopyranosyl)-oxy]-9-octadecenoic acid 1 0 ,4 00-lactone 6 0 ,6 00-diacetate in lactone (SL-1) and free-acid (SL-1A) forms](profile/Richard-Ashby/publication/6293868/figure/fig2/AS:667630117584896@1536186832076/Structures-of-sophorolipids-The-17-L-2.png)
Structures of sophorolipids. The 17-L-[(2 0-O-b-glucopyranosyl-b-D-glucopyranosyl)-oxy]-9-octadecenoic acid 1 0 ,4 00-lactone 6 0 ,6 00-diacetate in lactone (SL-1) and free-acid (SL-1A) forms
Source publication
A simplified medium containing only soy molasses and oleic acid as ingredients was developed for the production of sophorolipids (SLs) from Candida bombicola. We achieved a product yield of 53 +/- 3 g of purified sophorolipids per liter of starting culture volume, which is 71 +/- 4% of the yield obtained with growth medium that also additionally co...
Contexts in source publication
Context 1
... of the sophorose entity. Furthermore, the fatty acid chain may or may not be lactonized to the sophorose unit. With few excep- tions, the most commonly found constituent of the SL-product mixture from C. bombicola is 17-L-[(2 0 - O-b-glucopyranosyl-b-D-glucopyranosyl)-oxy]-9-oc- tadecenoic acid 1 0 ,4 00 -lactone 6 0 ,6 00 -diacetate (SL-1; Fig. 1) and its free-acid form (SL-1A; Fig. 1) (Asmer et al. 1988). Other commonly found constituents in a SL product mixture are structural variants of SL-1 and SL-1A in which the lipid moiety is a hydroxy- hexadecanoic acid, may be unsaturated, and is hydroxylated at the x-(or terminal) position, and in which the glycoside moiety is either ...
Context 2
... the fatty acid chain may or may not be lactonized to the sophorose unit. With few excep- tions, the most commonly found constituent of the SL-product mixture from C. bombicola is 17-L-[(2 0 - O-b-glucopyranosyl-b-D-glucopyranosyl)-oxy]-9-oc- tadecenoic acid 1 0 ,4 00 -lactone 6 0 ,6 00 -diacetate (SL-1; Fig. 1) and its free-acid form (SL-1A; Fig. 1) (Asmer et al. 1988). Other commonly found constituents in a SL product mixture are structural variants of SL-1 and SL-1A in which the lipid moiety is a hydroxy- hexadecanoic acid, may be unsaturated, and is hydroxylated at the x-(or terminal) position, and in which the glycoside moiety is either non-acetylated or mono-acetylated at ...
Citations
... These ratio values are higher than those achieved by Zhang et al. (2018) applying gravity separation at lab scale (74 %). Moreover, this finding is aligned with Solaiman et al. (2007), who reported that the exclusion of yeast extract and urea from the fermentation media, coupled with the use of soy molasses as the nutrient source, resulted in the attainment of pure SL in lactone form, with a purity of 87 % and a volumetric productivity of 53 ± 3 g/L. As reported by Ahalliya et al. (2023), the synthesis of the hydrophilic and hydrophobic moiety and the composition of biosurfactant congeners will change and rely on the carbon source used by the microorganism. ...
To explore a sustainable sophorolipid production, several hydrolysates from agricultural byproducts, such as
wheat feed, rapeseed meal, coconut waste and palm waste were used as nitrogen sources. The four hydrolysates
overperformed the controls after 168 h of fermentation using Starmerella bombicola ATCC 22214. Wheat feed and
coconut waste hydrolysates were the most promising feedstocks presenting a linear relationship between yeast
growth and diacetylated lactonic C18:1 production at total nitrogen concentrations below 1.5 g/L (R2 = 0.90 and
0.83, respectively). At 0.31 g/L total nitrogen, wheat feed hydrolysate achieved the highest production, yielding
72.20 ± 1.53 g/L of sophorolipid crude extract and 60.05 ± 0.56 g/L of diacetylated lactonic C18:1 at shake
flask scale with productivities of 0.43 and 0.36 g/L/h, respectively. Results were confirmed in a 2-L bioreactor
increasing 15 % diacetylated lactonic C18:1 production. Moreover, wheat feed hydrolysate supplemented only
with a hydrophobic carbon source was able to produce mainly diacetylated lactonic C18:1 congener (88.5 %
wt.), suggesting that the composition of the hydrolysate significantly influences the congeners profile. Overall,
this study provides valuable insights into agricultural byproduct hydrolysates as potential nitrogen feedstocks for
sophorolipid production and their further application on industrial biotechnology.
... Due to its elevated nitrogen-containing molecule content, soy molasses has the potential to be utilized as a nitrogen source in microbial fermentation, contributing to the production of proteins and peptides. As per the findings of Solaiman et al. (2007), the synthesis of Sophorolipids (SLs) by C. bombicola achieved a volumetric yield of 53 g/l culture when soy molasses was solely employed as a combined nitrogen and carbon source, along with oleic acid serving as a lipid co-substrate (Table 4). ...
... It's noteworthy that FMC was incorporated into test foods as an additive to the existing formulations without replacing any of the original ingredients (Wright et al., 2014). Molasses are enriched with essential minerals such as magnesium, calcium, and potassium, potentially (Solaiman et al., 2007) Beet molasses and residual oil cake 25.10 (Rodríguez et al., 2021) Sugar cane molasses 10-23.25 (Celligoi et al., 2020;Daverey & Pakshirajan, 2009) Sugar cane molasses and chicken fat 39.81 (Celligoi et al., 2020) Soy molasses and dairy industry wastewater 38.76 (Daverey & Pakshirajan, 2009) Soy molasses 75 (Solaiman et al., 2007) contributing to improved carbohydrate metabolism. Additionally, magnesium deficiency has been associated with insulin resistance (Barbagallo & Dominguez, 2007), calcium supplementation has been linked to increased insulin sensitivity (Pikilidou et al., 2009), and low potassium levels have been linked to an increased risk of developing diabetes, especially in young men (Chatterjee et al., 2012). ...
... It's noteworthy that FMC was incorporated into test foods as an additive to the existing formulations without replacing any of the original ingredients (Wright et al., 2014). Molasses are enriched with essential minerals such as magnesium, calcium, and potassium, potentially (Solaiman et al., 2007) Beet molasses and residual oil cake 25.10 (Rodríguez et al., 2021) Sugar cane molasses 10-23.25 (Celligoi et al., 2020;Daverey & Pakshirajan, 2009) Sugar cane molasses and chicken fat 39.81 (Celligoi et al., 2020) Soy molasses and dairy industry wastewater 38.76 (Daverey & Pakshirajan, 2009) Soy molasses 75 (Solaiman et al., 2007) contributing to improved carbohydrate metabolism. Additionally, magnesium deficiency has been associated with insulin resistance (Barbagallo & Dominguez, 2007), calcium supplementation has been linked to increased insulin sensitivity (Pikilidou et al., 2009), and low potassium levels have been linked to an increased risk of developing diabetes, especially in young men (Chatterjee et al., 2012). ...
Molasses is a valuable byproduct in the sugar and citrus fruit processing industries. This versatile substance used in various sectors, including beverage production, acetic acid synthesis, baker’s yeast cultivation, formulation of animal feed components, and even as a fertilizer. Beet molasses is used for creation of diverse bakery and confectionery products. In agriculture, beet sugar molasses is employed to enhance nutrient uptake efficiency and stimulate soil biological activity. Molasses also contributes to human health. Sugarcane molasses serves as a source of iron, containing approximately 0.7% iron by weight. Studies have indicated that molasses can have positive effects on glucose regulation, reducing both the peak and total levels of glucose, enhancing the secretion of insulin, amylin, and gastric inhibitory polypeptide after oral intake. Despite its widespread usage, molasses had its own drawbacks like it causes diseases (molasses toxicity, urea toxicity, and bloat) and increased greenhouse gas emissions.
... The results that focused on the residues used as nitrogen sources (RHP, RAC, and RSO) are congruent with those reported by Ma et al. (2011), who reported that inorganic N sources such as ammonium sulfate encourage the formation of acidic SL, while organic N sources promote the production of lactonic SL, which is confirmed with RHP results. The literature reports that there is a knowledge gap regarding alternative nitrogen sources for BS production (Solaiman et al., 2007;Wongsirichot et al., 2021). In this context, our research outcomes contribute positively to waste valorization in the SL production framework. ...
The use of alternative feedstocks such as industrial or food waste is being explored for the sustainable production of sophorolipids (SLs). Microbial biosurfactants are mainly produced via submerged fermentation (SmF); however, solid-state fermentation (SSF) seems to be a promising alternative for using solid waste or byproducts that could not be exploited by SmF. Applying the advantages that SSF offers and with the aim of revalorizing industrial organic waste, the impact of carbon and nitrogen sources on the relationship between yeast growth and SL production was analyzed. The laboratory-scale system used winterization oil cake as the solid waste for a hydrophobic carbon source. Pure hydrophilic carbon (glucose) and nitrogen (urea) sources were used in a Box–Behnken statistical design of experiments at different ratios by applying the response surface methodology. Optimal conditions to maximize the production and productivity of diacetylated lactonic C18:1 were a glucose:nitrogen ratio of 181.7:1.43 (w w⁻¹ based on the initial dry matter) at a fermentation time of 100 h, reaching 0.54 total gram of diacetylated lactonic C18:1 with a yield of 0.047 g per gram of initial dry mass. Moreover, time course fermentation under optimized conditions increased the SL crude extract and diacetylated lactonic C8:1 production by 22% and 30%, respectively, when compared to reference conditions. After optimization, industrial wastes were used to substitute pure substrates. Different industrial sludges, OFMSW hydrolysate, and sweet candy industry wastewater provided nitrogen, hydrophilic carbon, and micronutrients, respectively, allowing their use as alternative feedstocks. Sweet candy industry wastewater and cosmetic sludge are potential hydrophilic carbon and nitrogen sources, respectively, for sophorolipid production, achieving yields of approximately 70% when compared to the control group.
... Different hydrophobic carbon sources affected the yield and composition of SLs [35][36][37][38][39]. glucose as hydrophilic carbon source, sunflower seed oil, the fried waste oil, cooked tung oil and raw tung oil were used as hydrophobic carbon source for fermentation. ...
Sophorolipid (SLs) are surface active compounds that have excellent surface-lowering properties. SLs was produced by Starmerella bombicola (CGMCC1576) yeast with sunflower seeds oil, fried waste oil, cooked tung oil and raw tung oil used as hydrophobic carbon sources. The results showed that the strain could use sunflower seed oil and fried waste oil as hydrophobic carbon sources to produce SLs, and the yields were 44.52 and 39.09 gL-1, and it could not use cooked tung oil and raw tung oil. Analysis by high performance liquid chromatography-high resolution mass spectrometry (HPLC-MS/MS) showed that the main composition and structure of SLs produced by fermentation using waste fried waste oil were similar to that of sunflower seed oil as hydrophobic carbon source. The yield of SLs was the highest when the fried waste oil was used as hydrophobic carbon source, glucose 8%, waste oil 6% and yeast 0.3%. When fried waste oil was used as hydrophobic carbon source in a parallel 4-strand fermentation tank (FT), the combination with the largest yield and the most cost saving was that 3% of fried waste oil was added into the initial medium, and another 3% was again added after 72h of fermentation. The total yield of SLs was 121.28 gL-1, and the yield of lactone SLs was 48.07 gL-1.
... Also, the soy molasses that contains high fermentable carbohydrates (30 wv −1 %) and about 60 wv −1 % of solids carbohydrates was examined for economical production of SLs by C. bombicola and obtained 21 g L −1 of SLs [11]. The application of soy molasses as a carbon and nitrogen source of C. bombicola yielded 55 g L −1 of SLs [12]. ...
The application of industrial wastes in the fermentation process could significantly reduce the cost of biological products. In this study, the sunflower and soybean oil soap stocks as the inherent by-products of refinery vegetable oil manufacturers treated by a degumming process to purify the free fatty acids (FFAs). The obtained sunflower fatty acids (SFFA) and soybean fatty acids (SBFA) were used as hydrophobic carbon sources of C. catenulata cells to produce a beneficial biosurfactant namely sophorolipids (SLs). The results showed the test cell grows faster on the SFFA and SBFA versus refined sunflower oil (RSFO) and refined soybean oil (RSBO) as hydrophobic carbon sources and produced higher SLs after the late logarithmic growth. The highest specific growth rate and the volumetric SL production were obtained at 0.0475 h⁻¹ and 0.101 g L⁻¹ h⁻¹ for the SFFA system, respectively. The emulsification capacity of the produced SLs was examined to form a water-soybean oil microemulsion. The emulsification index (E24%) was 70.0 and 63.3% at 500 g L⁻¹ of the SLs obtained from SFFA and SBFA, respectively. The measurement of surface tension at different SL concentrations showed a critical micelle concentration of about 220 mg L⁻¹ and 230 mg L⁻¹ for these SLs.
Graphical Abstract
... Sucrose molasses and three different oils were used as carbon sources for the fermentation of SLs and when sucrose molasses and soybean oil were used as carbon sources, SLs produced the highest titer of 23.3 ± 1.6 g/L, which was equivalent to glucose medium and greatly reduced the production cost [14]. By using soybean molasses and oleic acid as substrates, the yield of SLs was 53.0 ± 2.8 g/L, which reached about 70% of that produced from glucose medium [15]. In addition, researchers have also used deproteinized whey concentrate [13], sweetwater [12], etc., to replace hydrophilic carbon sources (glucose) to produce SLs. ...
A large-scale application of sophorolipids (SLs) was blocked by their high production cost. One feasible way to reduce the cost of SL production is to develop cheap feedstocks as the substrates for SL fermentation. In the present work, cottonseed molasses (CM), a waste from raffinose production, was used as the hydrophilic substrate;, and cottonseed oil (CO) was used as a hydrophobic substrate for SL production by Starmerella bombicola CGMCC 1576. The primary optimization of carbon sources, nitrogen source and inorganic salts, produced 57.6 ± 2.3 g/L of total SLs and 24.0 ± 1.2 g/L of lactonic SLs on CM and CO, almost equal to the titer of SLs produced from glucose and oleic. A response surface method was applied to optimize the fermentation medium for growth and SL production of S. bombicola. The production of total SLs reached 58.4 ± 3.4 g/L, and lactonic SLs were elevated to more than 25.0 ± 1.9 g/L. HPLC–MS analysis showed that the compositions of SLs produced by S. bombicola on CM and CO were very similar to those on glucose and oleic acid. These results suggested that cottonseed molasses and cottonseed oil can be used as renewable cheap substrates for the reduced-cost production of SLs.
... The species in Figure 5 differ in terms of the presence of an acidic group. SL-1 consists of the 17-L-[(2 0-O-b-glucopyranosyl-b-D-glucopyranosyl)-oxy]-9-octadecenoic acid 1 0,4 00-lactone 6 0,6 00-diacetate in lactone, while, SL-1A is a free-acid form (Solaiman et al. 2007). ...
... Molecular structures of sophorolipid biosurfactants(Solaiman et al. 2007). ...
Today, with the ever-increasing concerns about the widespread environmental impact of the mining industry, the movement of the mineral processing sectors, which heavily rely on various chemical and petroleum-origin reagents, to the green industry is imperative. Due to the advantages biotechnological approaches provide, bioprocessing is considered a benign alternative to conventional mineral processing techniques. Recent fundamental research works have directed the attention to the development of biotechnology and using microorganisms in the new field of biobeneficiation, especially bioflotation. The current review categorizes bioflotation methods into direct and indirect processes giving an in-depth insight into their concepts. Furthermore, this study provides a comprehensive review of research on different aspects of bioflotation, such as the effects of operating (mainly solid content and pH) and biotechnological parameters, potential mechanisms, and unexplored points, but from different, and practical viewpoints. Recent studies were summarized by categorizing microorganisms based on their wall structures, and growth temperature. It was disclosed based on the literature data that the nutritional requirement of variant microorganisms was only chemolithotroph. Further, the conducted research in investigating optimum conditions for maximization of contact angle and adhesion forces to reach the maximum recovery were reviewed. In addition, existing problems and challenges of this field were investigated and it was found that economic barriers and obscurities were the main obstacles of industrial application in mining and mineral processing industries. Finally, new perspectives and suggestions were presented to shed light on future research and help to solve the challenges currently facing its application.
... Hence, both soybean molasses and glycerin have become attractive feedstock, because of their high levels of potentially fermentable sugars and high carbon content, respectively, which favor microbial growth and allow their use in bioprocess treatments, such as AD, contributing to cost reduction and environmental compliance ( Solaiman et al., 2007 ;Batista et al., 2020 ). Furthermore, the use of these biodegradable byproducts in the AD process is seen as a means of adapting the processes to circular economy principles ( Nagarajan et al., 2021 ;Wang and Serventi, 2019 ). ...
With the ever-growing environmental concern about natural resources depletion and the search for alternative energy sources, anaerobic digestion technology emerges as a core process in biorefineries. One of the limiting factors for full-scale use of this process is the scarcity of studies that technically and economically evaluate more flexible and unconventional technologies, such as Anaerobic Sequencing Batch Biofilm Reactors (AnSBBR) with immobilized biomass. Therefore, this paper carried out a techno-economic evaluation regarding the implementation of AnSBBR reactors, on an industrial scale, in the treatment of soybean molasses and glycerin. The assessment was based on the best published results presented by this type of reactor on a laboratory scale. The scale-up estimate resulted in a configuration of 8 AnSBBR reactors with 1,000 m³ each in the treatment of 59 tons-molasses.day-1. The energy produced by this system could reach 18.6 GWh.year-1 and would have an initial investment of USD 7.6 million with an annual return of USD 2.2 million. On treating 17 tons-glycerin.day-1, the estimate resulted in a configuration of 6 AnSBBR reactors with 900 m³ each. The energy produced could reach 6.3 GWh.year-1 and would have an initial investment of USD 5.8 million with an annual return of USD 1 million.
... By relativizing this amount of protein to total nitrogen (N) content according to the Kjeldahl method, we realized that the studied molasses contains about 0.87% which is largely below the range of 1.4 to 2.1% of raw molasses weight (Jevtic-Mucibabic et al. 2011). Nevertheless, with this nitrogen content, the molasses studied could be reused as a cheap nitrogen source for various yeast strains in fermentation industy (Solaiman et al. 2007). ...
Suitable methodologies and modern research facilities such as gas chromatography (GC) coupled with atomic absorption spectrometry (AAS) were used to characterize sugarcane molasses in order to foresee its reuse potential, as it has long been considered as a neglected by-product of the sugar industry in Côte d’Ivoire. The results showed that molasses dry matters (DM) contain about 75% of simple sugars essentially made up of sucrose (62.50%), glucose (14.38%) and fructose (14.39%). Proteins and nitrogen represent 5.45% and 0.87% of the DM respectively. The ashes representing 16.61% of DM were full of potassium (K⁺) with a rate of 45,209 ± 34.94 mg/kg. Lesser contents in magnesium (Mg²⁺: 2,109 mg/kg), calcium (Ca²⁺: 2,050 mg/kg), sodium (Na⁺: 551 mg/kg), phosphorus (PO³⁻: 260 mg/kg), iron (Fe²⁺: 166 mg/kg), manganese (Mn²⁺: 23 mg/ kg), zinc (Zn²⁺: 6 mg/kg) and copper (Cu²⁺: 4 mg/kg) were also quantified. These interesting contents in crude proteins, nitrogen and various essential minerals make molasses, an important by-product of the sugar industry, as it can be reused as a fertilizer in agriculture and as an ingredient in the preparation of certain foods for new-borns and pregnant women. The high content of simple carbohydrates makes molasses an ideal raw material for the production of bioethanol, a high value added and environmentally friendly product of global relevant interest.
... The yield of biosurfactant was found to be 21 g/L at flask level. The research group further suggested that the exploitation of soy molasses along with oleic acid could be a better substitute for carbon and nitrogen source for the growth of C. bombicola, which showed sophorolipid yield of 55 g/L (Solaiman et al., 2007). Another yeast namely, Saccharomyces cerevisiae produced biosurfactant by utilizing corn steep liquor and soybean frying oil. ...
Waste generation is becoming a global concern owing to its adverse effects on environment and human health. The utilization of waste as a feedstock for production of value-added products has opened new avenues contributing to environmental sustainability. Microorganisms have been employed for production of biosurfactants as secondary metabolites by utilizing waste streams. Utilization of waste as a substrate significantly reduces the cost of overall process. Biosurfactant(s) derived from these processes can be utilized in environmental and different industrial sectors. This review focuses on global market of biosurfactants followed by discussion on production of biosurfactants from waste streams such as agro-industrial waste and waste cooking oil. The need for waste stream derived circular bioeconomy and scale up of biosurfactant production have been narrated with applications of biosurfactants in environment and industrial sectors. Road blocks and future directions for research have also been discussed.
