Optimization of Inocula Conditions for Enhanced Biosurfactant Production by Bacillus subtilis SPB1, in Submerged Culture, Using Box–Behnken Design

Optimization of the Operational Conditions to Produce Extracellular and Cell-Bound Biosurfactants by Aneurinibacillus aneurinilyticus Using Corn Steep Liquor as a Unique Source of Nutrients

The relevance of this work lies in the fact that it is the first time that corn steep liquor (CSL) has been proposed as a unique source of nutrients for producing biosurfactants in a controlled fermentation and Aneurinibacillus aneurinilyticus, isolated from CSL, has been evaluated for producing extracellular and cell-bound biosurfactants in a controlled fermentation, using secondary raw materials as a source of nutrients. In the present study, A. aneurinilyticus was inoculated into the culture medium containing sterilized CSL solutions (100–400 g L−1) and incubated using different temperatures (20–60 °C) and fermentation times (8–30 days). The dependent variables under study were the concentration of extracellular biosurfactants and cell-bound biosurfactant production in terms of critical micellar concentration (CMC), as well as the C/N ratio for cell-bound biosurfactant extracts. It was observed that CSL could increase the concentration of extracellular biosurfactants produced by A. aneurinilyticus if these were fermented during 19 days at 40 °C, using 250 g L−1 of CSL; a mean value of 6 g L−1 for extracellular biosurfactants and favorable CMC concentrations enabled the detection of cell-bound biosurfactant extracts under these conditions. Hence, these conditions could be considered optimal for producing both extracellular and cell-bound biosurfactants from CSL.

A novel antimicrobial peptide YS12 isolated from Bacillus velezensis CBSYS12 exerts anti-biofilm properties against drug-resistant bacteria

Nowadays, the abuse of antibiotics has led to the rise of multi-drug-resistant bacteria. Antimicrobial peptides (AMPs), with broad-spectrum antimicrobial activity have attracted considerable attention as possible alternatives to traditional antibiotics. In this work, we aimed to evaluate the antimicrobial and anti-biofilm activity of an antimicrobial peptide designed as YS12 derived from Bacillus velezensis CBSYS12. The strain CBSYS12 was isolated from Korean food kimchi and purified followed by ultrafiltration and sequential chromatographic methodology. Hereafter, Tricine SDS-PAGE revealed a single protein band of around 3.3 kDa that was further confirmed in situ inhibitory activity of the gel. A similar molecular weight (~ 3348.4 Da) protein also appeared in MALDI-TOF confirming the purity and homogeneity of peptide YS12. Intriguingly, YS12 revealed a strong antimicrobial activity with a minimum inhibitory concentration (MIC) value ranging from 6 to 12 μg/ml for both Gram-positive and Gram-negative bacteria, such as E. coli, P. aeruginosa, MRSA 4-5, VRE 82, and M. smegmatis. We also determined the mode of action of the peptide against pathogenic microorganisms using different fluorescent dyes. In addition, the anti-biofilm assay demonstrated that peptide YS12 was able to inhibit biofilm formation  around 80% for both bacterial strains E. coli and P. aeruginosa at 80 µg/ml. Notably, YS12 exhibited a greater biofilm eradication activity than commercial antibiotics. In summary, our study proposed that peptide YS12 may be used as a promising therapeutic agent to overcome drug and biofilm-related infections.

Optimization of Medium Components for Fed-Batch Fermentation Using Central Composite Design to Enhance Lichenysin Production by Bacillus licheniformis Ali5

Lichenysin, an amphiphilic biosurfactant with structural and physicochemical properties similar to surfactin, is produced by Bacillus licheniformis. Its low toxicity, good environmental compatibility, solubilization, foaming, emulsification and detergent activities have led to a wide range of applications in agricultural biocontrol, enhanced oil recovery, foaming agents for cosmetics and detergents for household cleaning products. However, despite the extraordinary surface-active properties and potential applications of lichenysin, the number of wild bacteria found so far is relatively low. Low titers and high costs are the main limiting factors for widespread industrial applications. In this study, a factorial design was used to optimize the composition of the medium for the production of lichenysin by Bacillus licheniformis Ali5. Firstly, the solutions of carbon, nitrogen, amino acids, inorganic salts and trace elements in the medium were evaluated in flasks using a single-factor optimization method. Meanwhile, the operating conditions were optimized in the same way. Afterwards, a partial factorial design was used to investigate the effect of six variables (five medium compositions and inoculum size) on lichenysin production. Based on the results obtained, the concentrations of sucrose and ammonium nitrate and the inoculum size were considered to be important for lichenysin production. Subsequently, a full factorial design was used to optimize these three variables. The optimized medium composition were sucrose 19.8 g/L, NH4NO3 3.9 g/L, K2HPO4·3H2O 4.0 g/L, MgSO4·7H2O 0.6 g/L, FeSO4·7H2O 0.1 g/L, CaCl2 0.01 g/L, NaCl 3.0, trace elements 1.2 mL/L. Finally, the titer of lichenysin after fed-batch fermentation reached 1425.85 mg/L, which was approximately 5.5 times higher than the titer of lichenysin from the original medium. Consequently, the method was further demonstrated to be suitable for lichenysin production.

Comprehensive Review on Applications of Surfactants in Vaccine Formulation, Therapeutic and Cosmetic Pharmacy and Prevention of Pulmonary Failure due to COVID-19

Our world is under serious threat of environmental degradation, climate change and in association with this the out breaks of diseases as pandemics. The devastating impact of the very recent COVID-19, The sharp increase in cases of Cancer, Pulmonary failure, Heart health has triggered questions for the sustainable development of pharmaceutical and medical sciences. In the search of inclusive and effective strategies to meet today’s demand, improvised methodologies and alternative green chemical, bio-based precursors are being introduced by scientists around the globe. In this extensive review we have presented the potentiality and Realtime applications of both synthetic and bio-based surfactants in bio-medical and pharmaceutical fields. For their excellent unique amphoteric nature and ability to solubilise in both organic and inorganic drugs, surfactants are one of the most potential candidates for bio-medicinal fields such as dermatology, drug delivery, anticancer treatment, surfactant therapy, vaccine formulation, personal hygiene care and many more. The self-assembly property of surfactants is a very powerful function for drug delivery systems that increases the bio-availability of the poorly aqueous soluble pharmaceutical products by influencing their solubility. Over the decades many researchers have reported the antimicrobial, anti-adhesive, antibiofilm, anti-inflammatory, antioxidant activities of surfactants regarding its utility in medicinal purposes. In some reports surfactants are found to have spermicidal and laxative activity too. This comprehensive report is targeted to enlighten the versatile applications of Surfactants in drug delivery, vaccine formulation, Cancer Treatment, Therapeutic and cosmetic Pharmaceutical Sciences and prevention of pulmonary failure due to COVID-19.

Lipopeptide Biosurfactants from Bacillus spp.: Types, Production, Biological Activities, and Applications in Food

Biosurfactants are a functionally and structurally heterogeneous group of biomolecules produced by multiple filamentous fungi, yeast, and bacteria, and characterized by their distinct surface and emulsifying ability. The genus Bacillus is well studied for biosurfactant production as it produces various types of lipopeptides, for example, lichenysins, bacillomycin, fengycins, and surfactins. Bacillus lipopeptides possess a broad spectrum of biological activities such as antimicrobial, antitumor, immunosuppressant, and antidiabetic, in addition to their use in skincare. Moreover, Bacillus lipopeptides are also involved in various food products to increase the antimicrobial, surfactant, and emulsification impact. From the previously published articles, it can be concluded that biosurfactants have strong potential to be used in food, healthcare, and agriculture. In this review article, we discuss the versatile functions of lipopeptide Bacillus species with particular emphasis on the biological activities and their applications in food.

Biosurfactant: A new frontier for greener technology and environmental sustainability

Petroleum hydrocarbons, oil, heavy metals pollution is becoming additional severe problem due to the growing call for crude oil and crude oil products related products in several fields of application. Such pollution have fascinated much considerations and attractions as it leads to ecological damages in both marines, aquatic and terrestrial ecosystems. Thus, different techniques including chemical surfactants and complex technologies have been proposed for their clean up from the environment, which in turn has detrimental effects on the environment. As of late, biosurfactant compounds have added much deliberation since they are considered as a reasonable option and eco-accommodating materials for remediation technology. The present society is confronting a few difficulties of usage, authorizing ecological protection and environmental change for the next generations. Biosurfactants hold the special property of minimizing and reducing the interfacial tension of liquids. Such features endure biosurfactants to afford a major part in emulsification, de-emulsification, biodegradability, foam formation, washing performance, surface activity, and detergent formulation, which have potential applications in the diverse industrial set-up. Conversations on cost-effective technologies, renewable materials, novel synthesis, downstream, upstream, emerging characterization techniques, molecular, and genetical engineering are substantial to produce biosurfactant of quality and quantity. Therefore, greater attention is being paid to biosurfactant production by identifying their environmental, and biotechnological applications. Be that as it may, the extravagant cost drew in with biosurfactants biotechnological synthesis and recovery can hamper their application in those areas. Notwithstanding these costs, biosurfactants can be used as these parts shows outstandingly high benefits that can at present beat the expenses incurred in the initial purification and downstream processes. Biosurfactant production by microorganisms is relatively considered one of the crucial know-how for improvement, growth, advancement, and environmental sustainability of the 21st century. There is a developing conversation around environmental safety and the significant role that biosurfactants will progressively play soon, for instance, the use of renewable by-products as substrates, potential reduction, re-use and recycling of waste and waste products. The review confers the usefulness of biosurfactants in the removal of environmental contaminants and, consequently, expanding environmental safety and drive towards greener technology.

Mixed fermentation of Aspergillus niger and Candida shehatae to produce bioethanol with ionic-liquid-pretreated bagasse

In this study, bagasse was pretreated with ionic liquid (IL) 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) and 1% NaOH solution for initial activation of bagasse. A mixed fermentation of treated bagasse by Aspergillus niger and Candida shehatae showed the optimal conditions with the addition of C. shehatae 12 h later at a 1:1 proportion to A. niger. To further improve the ethanol production and obtain optimal fermentation conditions, a Plackett-Burman design was applied to screen the significant formulation and process variables. The optimal ethanol fermentation conditions with IL pretreated bagasse were determined using response surface methodology by Box-Behnken design. Three variables "initial pH, (NH4)2SO4, fermentation time" were regarded as significant factors in the optimization study. The resulting optimum fermentation conditions for bioethanol was identified as: initial pH of 5.89, (NH4)2SO4 concentration of 0.40 g/50 mL, and fermentation time of 3.60 days. The verification experimental ethanol concentration was 8.14 g/L, which agreed with the predicted value. An enhancement of approximately 153.58% compared with initial fermentation conditions in ethanol production was found using optimized conditions. It demonstrated that optimization methodology had a positive effect on the improvement of ethanol production. Under the optimal fermentation medium and conditions, the ethanol production with IL-pretreated bagasse and untreated bagasse was 8.14 g/L and 5.03 g/L, respectively, which exhibited 62% increase, compared to initial conditions with production of 3.21 g/L and 2.67 g/L, respectively, which displayed 20% increase. Both under optimal and original fermentation conditions, compared to the fermentation medium with untreated bagasse, all the results indicated that IL-pretreated bagasse resulted in higher ethanol production than untreated bagasse, demonstrating that IL-pretreated bagasse successfully increased the ethanol production in the mixed fermentation by A. niger and C. shehatae.

Statistical Design, a Powerful Tool for Optimizing Biosurfactant Production: A Review

Biosurfactants (Bs) have been studied for decades and applied in different industrial sectors because of their competitive biochemical characteristics, and the fact that they are environmentally friendly. Current scientific investigations mainly involve the search for novel Bs producing organisms with attractive characteristics. Bs are expected to replace synthetic surfactants in the near future, but low production yields and inefficient downstream processes have prevented their widespread use. Although there are numerous reports on Bs optimization, to date there has been no critical compilation or revision of the statistical designs and strategies employed for improved production. The purpose of this mini review is to briefly discuss the factors that affect Bs production and the importance of statistical design as an essential tool for increasing production.

Response Surface Methodology for Optimizing the Production of Biosurfactant by Candida tropicalis on Industrial Waste Substrates

Biosurfactant production optimization by Candida tropicalis UCP0996 was studied combining central composite rotational design (CCRD) and response surface methodology (RSM). The factors selected for optimization of the culture conditions were sugarcane molasses, corn steep liquor, waste frying oil concentrations and inoculum size. The response variables were surface tension and biosurfactant yield. All factors studied were important within the ranges investigated. The two empirical forecast models developed through RSM were found to be adequate for describing biosurfactant production with regard to surface tension (R² = 0.99833) and biosurfactant yield (R² = 0.98927) and a very strong, negative, linear correlation was found between the two response variables studied (r = −0.95). The maximum reduction in surface tension and the highest biosurfactant yield were 29.98 mNm⁻¹ and 4.19 gL⁻¹, respectively, which were simultaneously obtained under the optimum conditions of 2.5% waste frying oil, 2.5%, corn steep liquor, 2.5% molasses, and 2% inoculum size. To validate the efficiency of the statistically optimized variables, biosurfactant production was also carried out in 2 and 50 L bioreactors, with yields of 5.87 and 7.36 gL⁻¹, respectively. Finally, the biosurfactant was applied in motor oil dispersion, reaching up to 75% dispersion. Results demonstrated that the CCRD was suitable for identifying the optimum production conditions and that the new biosurfactant is a promising dispersant for application in the oil industry.

Considering the Specific Impact of Harsh Conditions and Oil Weathering on Diversity, Adaptation, and Activity of Hydrocarbon-Degrading Bacteria in Strategies of Bioremediation of Harsh Oily-Polluted Soils

Weathering processes change properties and composition of spilled oil, representing the main reason of failure of bioaugmentation strategies. Our purpose was to investigate the metabolic adaptation of hydrocarbon-degrading bacteria at harsh conditions to be considered to overcome the limitations of bioaugmentation strategies at harsh conditions. Polluted soils, exposed for prolonged periods to weathered oil in harsh soils and weather conditions, were used. Two types of enrichment cultures were employed using 5% and 10% oil or diesel as sole carbon sources with varying the mineral nitrogen sources and C/N ratios. The most effective isolates were obtained based on growth, tolerance to toxicity, and removal efficiency of diesel hydrocarbons. Activities of the newly isolated bacteria, in relation to the microenvironment from where they were isoalted and their interaction with the weathered oil, showed individual specific ability to adapt when exposed to such factors, to acquire metabolic potentialities. Among 39 isolates, ten identified ones by 16S rDNA genes similarities, including special two Pseudomonas isolates and one Citrobacter isolate, showed particularity of shifting hydrocarbon-degrading ability from short chain n-alkanes (n-C12-n-C16) to longer chain n-alkanes (n-C21-n-C25) and vice versa by alternating nitrogen source compositions and C/N ratios. This is shown for the first time.

β-Amylase production from packaging-industry wastewater using a novel strain Paenibacillus chitinolyticus CKS 1

Transforming waste into valuable biotechnology products – the treatment of transport packaging wastewater withPaenibacillus chitinolyticusCKS1 for β-amylase and maltose production.