Study of biosurfactant extract from corn steep water as a potential ingredient in antiacne formulations.

BACKGROUND: This is a novel work that includes the use of a biosurfactant extract obtained from corn milling industry (named BS-CSW), with antimicrobial activity, as ingredient in formulations to treat acne vulgaris. METHODOLOGY: With this purpose, it was established an incomplete experimental design with 3 independent variables, based on the concentration of non-nano zinc oxide (ZnO) (0-2%), BS-CSW (0-5%) and salicylic acid (0-2%). RESULTS: This design allowed to obtain a theoretical model that calculates the inhibitory effect on Cutibacterium acnes (also named Propionibacterium acnes) for any formulation carried with the ingredients appointed before. It was observed a clear synergetic effect on the inhibition of C. acnes between ZnO and BS-CSW, in absence of salicylic acid. This fact allowed to reduce the concentration of ZnO, giving more ecofriendly and biocompatible formulations. CONCLUSIONS: It was observed that the biosurfactant extract, in formulations with intermediate concentration of ZnO (1%), possess an inhibitory effect on C. acnes considerably higher than ZnO alone and similar to ZnO (1%) with salicylic acid (1%). This fact demonstrates the enormous potential of this bioactive extract in antiacne formulations.

Sleep Challenges and Interventions in Children With Visual Impairment.

PURPOSE: To examine sleep patterns in a large and heterogeneous group of children with visual impairment. METHODS: A cross-sectional survey of parents of children with visual impairment was offered via the National Federation of the Blind and the National Organization for Albinism and Hypopigmentation. RESULTS: Complete survey results were available for 72 participants, aged 1 to 16 years. Parents of 52 (72%) children reported that their child had cycles of good sleep and bad sleep, and 50 (69%) reported that their child's sleep patterns caused significant stress for them or their family. Scores on the Childhood Sleep Habits Questionnaire (CSHQ) increased (> 41) in 64 (89%) children, indicating a likely clinically significant sleep problem. When compared to normative data from children aged 4 to 10 years, children in the current sample scored higher (more sleep problems) on all eight subscales on the CSHQ. The presence of comorbid developmental delay was most strongly associated with sleep problems. Supplemental melatonin and improving daytime and nighttime schedules or routines were reported as the most helpful for sleep. Many families reported a need for further information regarding melatonin use as a supplement. CONCLUSIONS: A high proportion of children with visual impairment experience clinically meaningful sleep problems, regardless of degree of light perception or visual acuity. There is a strong need for increased awareness and screening for sleep problems in this population. Potential treatment modalities, including supplemental melatonin, should be discussed with families. [J Pediatr Ophthalmol & Strabismus. 2022;59(2):77-86.].

Full-bandwidth electrophysiology of seizures and epileptiform activity enabled by flexible graphene microtransistor depth neural probes.

Mapping the entire frequency bandwidth of brain electrophysiological signals is of paramount importance for understanding physiological and pathological states. The ability to record simultaneously DC-shifts, infraslow oscillations (<0.1 Hz), typical local field potentials (0.1-80 Hz) and higher frequencies (80-600 Hz) using the same recording site would particularly benefit preclinical epilepsy research and could provide clinical biomarkers for improved seizure onset zone delineation. However, commonly used metal microelectrode technology suffers from instabilities that hamper the high fidelity of DC-coupled recordings, which are needed to access signals of very low frequency. In this study we used flexible graphene depth neural probes (gDNPs), consisting of a linear array of graphene microtransistors, to concurrently record DC-shifts and high-frequency neuronal activity in awake rodents. We show here that gDNPs can reliably record and map with high spatial resolution seizures, pre-ictal DC-shifts and seizure-associated spreading depolarizations together with higher frequencies through the cortical laminae to the hippocampus in a mouse model of chemically induced seizures. Moreover, we demonstrate the functionality of chronically implanted devices over 10 weeks by recording with high fidelity spontaneous spike-wave discharges and associated infraslow oscillations in a rat model of absence epilepsy. Altogether, our work highlights the suitability of this technology for in vivo electrophysiology research, and in particular epilepsy research, by allowing stable and chronic DC-coupled recordings.

Synthetic and Bio-Derived Surfactants Versus Microbial Biosurfactants in the Cosmetic Industry: An Overview.

This article includes an updated review of the classification, uses and side effects of surfactants for their application in the cosmetic, personal care and pharmaceutical industries. Based on their origin and composition, surfactants can be divided into three different categories: (i) synthetic surfactants; (ii) bio-based surfactants; and (iii) microbial biosurfactants. The first group is the most widespread and cost-effective. It is composed of surfactants, which are synthetically produced, using non-renewable sources, with a final structure that is different from the natural components of living cells. The second category comprises surfactants of intermediate biocompatibility, usually produced by chemical synthesis but integrating fats, sugars or amino acids obtained from renewable sources into their structure. Finally, the third group of surfactants, designated as microbial biosurfactants, are considered the most biocompatible and eco-friendly, as they are produced by living cells, mostly bacteria and yeasts, without the intermediation of organic synthesis. Based on the information included in this review it would be interesting for cosmetic, personal care and pharmaceutical industries to consider microbial biosurfactants as a group apart from surfactants, needing specific regulations, as they are less toxic and more biocompatible than chemical surfactants having formulations that are more biocompatible and greener.

Can a Corn-Derived Biosurfactant Improve Colour Traits of Wine? First Insight on Its Application during Winegrape Skin Maceration versus Oenological Tannins.

In winemaking, oenological tannins are used to preserve wine colour by enhancing the antioxidant activity, taking part in copigmentation, and forming polymeric pigments with anthocyanins. As a novel processing aid, in this study, a biosurfactant extract was evaluated as a solubilizing and stabilizing agent of anthocyanins in red wine. The biosurfactant extract under evaluation was obtained from a fermented residual stream of the corn milling industry named corn steep liquor (CSL). Two red winegrape varieties (Vitis vinifera L. cv. Aglianico and Cabernet sauvignon) were studied for anthocyanin content and profile, and colour traits, during simulated skin maceration for 7 days at 25 °C, as well as polymerization and copigmentation at the end of maceration. A model wine solution was used as a control, which was added either with the CSL biosurfactant or with four different oenological tannins (from grape skin, grape seed, quebracho, and acacia). The results showed that CSL biosurfactant addition improved the colour properties of skin extracts by the formation of more stable compounds mainly through copigmentation interactions. These preliminary results highlighted that the effectiveness of CSL biosurfactant is variety-dependent; however, there is no significant protection of individual anthocyanin compounds as observed for delphinidin and petunidin forms using quebracho tannin.

Predictive factors of Boston Type I Keratoprosthesis outcomes: A long-term analysis.

PURPOSE: To study the long-term visual- and device retention-related outcomes and complications of the Boston Type I Keratoprosthesis (KPro). METHODS: Single-center, retrospective cohort study of all patients undergoing KPro implantation from February 2007 to April 2014 with at least 5 years of follow-up. RESULTS: 68 eyes from 65 patients underwent KPro implantation during the study period. At 5 and 10 years, the probability of maintaining or improving visual acuity (VA) was 75.0% and 66.7%, respectively, and the probability of KPro retention was 89.2% and 89.2%, respectively. Initial device retention rate at 10 years was significantly lower in those with underlying ocular surface disease (46.8% [30.6-63.2] vs 75.8% [61.0-90.7], P = 0.03), while other baseline characteristics showed no significant association. Final VA was more likely to be stable or improved in patients with fewer failed grafts (2 [1-6] vs 3 [1-6], P < 0.01), and a final VA of 20/200 or better was more likely in primary KPro eyes (44.8% [26.7-62.9] vs 19.4% [6.5-32.3], P = 0.03). Combined KPro-vitrectomy eyes were more likely to have stable or improved final VA than non-vitrectomy eyes (88.5% [76.2-100.0] vs 64.1% [49.1-79.1], P = 0.04). All complications had increasing incidence beyond 5 years; in particular, corneal melt, surgical glaucoma interventions, and endophthalmitis tended to have late presentations, with 79.0%, 78.6%, and 88.9% of these complications occurring beyond one year, respectively. CONCLUSIONS: KPro devices show favorable long-term visual and retention outcomes in select patients. Careful long-term, multidisciplinary follow-up is warranted to address potential complications.

Novel Multifunctional Biosurfactant Obtained from Corn as a Stabilizing Agent for Antidandruff Formulations Based on Zn Pyrithione Powder.

The cosmetic industry provides a wide variety of shampoos to treat dandruff, containing insoluble ingredients such as Zn pyrithione. However, the solubility of this active ingredient is quite limited in both water and oil media; thus, antidandruff formulations must include a large amount of chemically synthesized stabilizing ingredients to avoid their precipitation. In this work, the stabilization of Zn pyrithione in O/W emulsions using a biosurfactant (BS) extract and Tween 80 is studied. The study includes an incomplete factorial design based on the tea tree oil/water ratio and both surfactant and biosurfactant concentrations. The formulations are characterized in terms of particle size, stability after 30 days, and solubility of Zn pyrithione. The formulation that provided the most favorable results contains Tween 80 (5%) and BS extract (2.5%), with an O/W ratio of 0.01. This provides the smallest particle size (40.5 µm), good stability after 30 days (91.0%), and the highest solubility of Zn pyrithione (59%). The results obtained enable the use of the combination of BS extract and Tween 80 as bio/surfactants of antidandruff shampoo formulations, along with another antiseptic agent such as tea tree oil. Furthermore, this is the first work where a biosurfactant is considered to be a stabilizing agent in antidandruff formulations.

Distortion-Free Sensing of Neural Activity Using Graphene Transistors.

Graphene solution-gated field-effect transistors (g-SGFETs) are promising sensing devices to transduce electrochemical potential signals in an electrolyte bath. However, distortion mechanisms in g-SGFET, which can affect signals of large amplitude or high frequency, have not been evaluated. Here, a detailed characterization and modeling of the harmonic distortion and non-ideal frequency response in g-SGFETs is presented. This accurate description of the input-output relation of the g-SGFETs allows to define the voltage- and frequency-dependent transfer functions, which can be used to correct distortions in the transduced signals. The effect of signal distortion and its subsequent calibration are shown for different types of electrophysiological signals, spanning from large amplitude and low frequency cortical spreading depression events to low amplitude and high frequency action potentials. The thorough description of the distortion mechanisms presented in this article demonstrates that g-SGFETs can be used as distortion-free signal transducers not only for neural sensing, but also for a broader range of applications in which g-SGFET sensors are used.

The effect of the presence of biosurfactant on the permeation of pharmaceutical compounds through silicone membrane.

The permeation of ten model drugs through silicone membrane was analysed to investigate the effect of the presence of a biosurfactant obtained from corn steep liquor. The ten selected pharmaceutical compounds were chosen to include a diverse range of physicochemical properties, such as variable hydrophobicities, pKa's, molecular masses and degrees of ionisation. When compared with compound permeation alone, the additional inclusion of biosurfactant in the donor phase altered the rate and extent of permeation. It significantly enhanced permeation for five of the compounds, whereas it decreased permeation for four of the compounds and remained approximately the same for the tenth compound. These effects were observed at both biosurfactant concentrations considered, namely 0.005 mg/mL, i.e. below the critical micellar concentration (CMC) and 0.500 mg/mL, i.e. above the CMC of the biosurfactant. Upon analysing permeation change with respect to physicochemical properties of the compounds, it was determined that compounds with a relative molecular mass below 200 resulted in an increase in permeation with biosurfactant present, and those above 200 resulted in a decrease in permeation with biosurfactant present. This effect was therefore attributed to the formation of a drug-biosurfactant interaction that enhanced permeation of smaller compounds, yet retarded permeation for those with a higher molecular mass. These in vitro findings can be considered an indication of potential novel formulation options that incorporate biosurfactant to create transdermal products that have bespoke permeation profiles.

High-resolution mapping of infraslow cortical brain activity enabled by graphene microtransistors.

Recording infraslow brain signals (<0.1 Hz) with microelectrodes is severely hampered by current microelectrode materials, primarily due to limitations resulting from voltage drift and high electrode impedance. Hence, most recording systems include high-pass filters that solve saturation issues but come hand in hand with loss of physiological and pathological information. In this work, we use flexible epicortical and intracortical arrays of graphene solution-gated field-effect transistors (gSGFETs) to map cortical spreading depression in rats and demonstrate that gSGFETs are able to record, with high fidelity, infraslow signals together with signals in the typical local field potential bandwidth. The wide recording bandwidth results from the direct field-effect coupling of the active transistor, in contrast to standard passive electrodes, as well as from the electrochemical inertness of graphene. Taking advantage of such functionality, we envision broad applications of gSGFET technology for monitoring infraslow brain activity both in research and in the clinic.

Effect of biosurfactant extract obtained from the corn-milling industry on probiotic bacteria in drinkable yogurt.

BACKGROUND: Recent studies have proven that biosurfactants (BS) obtained from controlled fermentation have shown surfactant and antimicrobial properties. In this work a biosurfactant extract obtained from a raw agroindustrial stream from the corn-milling industry was introduced into a drinkable probiotic yogurt containing Lactobacillus casei. RESULTS: The effect of the biosurfactant extract on the probiotic population was determined under different biosurfactant concentration, temperature, and time conditions. This extract was able to reduce the surface tension of water by 30 mN/m and it was observed that its addition to a drinkable probiotic yogurt did not negatively affect the biomass of L. casei during incubation. It also had a positive effect on the population of L. casei, increasing the growth of the probiotic bacterium in the yogurt under optimum temperature conditions for the growth of L. casei, in the range of 30-40 °C. Likewise, the biosurfactant extract did not modify the homofermentative pathway of L. casei; hence no acetic acid was detected in the presence of the biosurfactant extract in the drinkable yogurt. CONCLUSION: This is the first time that a biosurfactant extract, obtained from natural sources, has been introduced into a food product like a drinkable probiotic yogurt, producing a positive effect in the growth of probiotic bacterium. © 2018 Society of Chemical Industry.

Kinetic and morphology study of alginate-vineyard pruning waste biocomposite vs. non modified vineyard pruning waste for dye removal.

In this work a comparative bioadsorption study between a biocomposite consisting of hydrolysed vineyard pruning waste entrapped in calcium alginate spheres and non entrapped vineyard residue was carried out. Results have demonstrated that the biocomposite based on lignocellulose-calcium alginate spheres removed 77.3% of dyes, while non entrapped lignocellulose eliminated only removed 27.8% of colour compounds. The experimental data were fitted to several kinetic models (pseudo-first order, pseudo-second order, Chien-Clayton model, intraparticle diffusion model and Bangham model); being pseudo-second order the kinetic model that better described the adsorption of dyes onto both bioadsorbents. In addition, a morphological study (roughness and shape) of alginate-vineyard biocomposite was established under extreme conditions, observing significant differences between hydrated and dehydrated alginate-vineyard biocomposite. The techniques used to carry out this morphological study consisted of scanning electron microscopy (SEM), perfilometry and 3D surface analysis.

Sewage Sludge Polycyclic Aromatic Hydrocarbon (PAH) Decontamination Technique Based on the Utilization of a Lipopeptide Biosurfactant Extracted from Corn Steep Liquor.

A decontamination technique based on the utilization of a lipopeptide biosurfactant extracted from corn steep liquor has been developed to eliminate polycyclic aromatic hydrocarbons (PAHs) from sewage sludge. High concentrations of PAHs were used during experiments observing that 408.3 mg/kg of naphthalene was almost completely mobilized and biodegraded, only 1.7% of naphthalene remained in the sewage sludge, whereas anthracene and pyrene were reduced up to 51.7 and 69.4%, respectively. The biodegradation of PAHs was fitted to several kinetic models (zero- and first-order kinetic models), observing good correlation coefficient values when biodegradation was described by the first-order kinetic model. Experimental results suggest that biosurfactant extracted from corn steep liquor may have great potential, as an ecofriendly washing agent, for the treatment of sewage sludge contaminated with PAHs. Therefore, in situ application of natural biosurfactants may be considered to be a good remediation alternative as they are not hazardous for water and soil organisms.

Optimization of extraction conditions and fatty acid characterization of Lactobacillus pentosus cell-bound biosurfactant/bioemulsifier.

BACKGROUND: There is currently much interest in the use of natural biosurfactants and bioemulsifiers, mainly in the cosmetic, pharmaceutical and food industries. However, there are no studies on the optimization of the extraction conditions of cell-bound biosurfactants. In this work, a biosurfactant with emulsifier properties was extracted from Lactobacillus pentosus cells, under different extraction conditions, and characterized. RESULTS: During extraction, the most influential independent variable, concerning the emulsifying capacity of biosurfactant, was the operation time, followed by temperature and salt concentration. Biosurfactant from L. pentosus was evaluated by Fourier transform infrared spectroscopy and the composition of fatty acids was analyzed by gas chromatography-mass spectrometry. The hydrophobic chain of the biosurfactant from L. pentosus comprises 548 g kg(-1) linoelaidic acid (C18:2), 221 g kg(-1) oleic or elaidic acid (C18:1), 136 g kg(-1) palmitic acid (C16) and 95 g kg(-1) stearic acid (C18). In addition, emulsions of water and rosemary oil were stabilized with a biosurfactant produced by L. pentosus and compared with emulsions stabilized with polysorbate 20. CONCLUSION: The optimum extraction conditions of biosurfactant were achieved at 45 °C at 120 min and using 9 g kg(-1) of salt. In all the assays biosurfactant from L. pentosus yielded more stable emulsions and higher emulsion volumes than polysorbate 20.

CHOPCHOP: a CRISPR/Cas9 and TALEN web tool for genome editing.

Major advances in genome editing have recently been made possible with the development of the TALEN and CRISPR/Cas9 methods. The speed and ease of implementing these technologies has led to an explosion of mutant and transgenic organisms. A rate-limiting step in efficiently applying TALEN and CRISPR/Cas9 methods is the selection and design of targeting constructs. We have developed an online tool, CHOPCHOP (https://chopchop.rc.fas.harvard.edu), to expedite the design process. CHOPCHOP accepts a wide range of inputs (gene identifiers, genomic regions or pasted sequences) and provides an array of advanced options for target selection. It uses efficient sequence alignment algorithms to minimize search times, and rigorously predicts off-target binding of single-guide RNAs (sgRNAs) and TALENs. Each query produces an interactive visualization of the gene with candidate target sites displayed at their genomic positions and color-coded according to quality scores. In addition, for each possible target site, restriction sites and primer candidates are visualized, facilitating a streamlined pipeline of mutant generation and validation. The ease-of-use and speed of CHOPCHOP make it a valuable tool for genome engineering.

Development of new active packaging films coated with natural phenolic compounds to improve the oxidative stability of beef.

The aim is to develop active packaging films containing natural antioxidants and to evaluate their capacity to enhance the oxidative stability of beef during refrigeration. The antioxidant activity of a natural extract obtained from a brewery residual waste was evaluated and compared with that of a commercial rosemary extract and two synthetic antioxidants (BHT and propyl gallate). Different concentrations of each antioxidant were also added directly to beef samples, resulting in a reduction in lipid oxidation of up to 70-80% relative to the control. Active antioxidant films coated with PVPP-WS extract reduced lipid oxidation by up to 80%, relative to the control, during cold storage. The use of active packaging films containing natural extracts could improve the oxidative stability of meat products and should therefore be of great interest in the food industry.

Fractionation and purification of bioactive compounds obtained from a brewery waste stream.

The brewery industry generates waste that could be used to yield a natural extract containing bioactive phenolic compounds. We compared two methods of purifying the crude extract-solid-phase extraction (SPE) and supercritical fluid extraction (SFE)--with the aim of improving the quality of the final extract for potential use as safe food additive, functional food ingredient, or nutraceutical. The predominant fractions yielded by SPE were the most active, and the fraction eluted with 30% (v/v) of methanol displayed the highest antioxidant activity (0.20 g L(-1)), similar to that of BHA. The most active fraction yielded by SFE (EC50 of 0.23 g L(-1)) was obtained under the following conditions: temperature 40 °C, pressure 140 bar, extraction time 30 minutes, ethanol (6%) as a modifier, and modifier flow 0.2 mL min(-1). Finally, we found that SFE is the most suitable procedure for purifying the crude extracts and improves the organoleptic characteristics of the product: the final extract was odourless, did not contain solvent residues, and was not strongly coloured. Therefore, natural extracts obtained from the residual stream and purified by SFE can be used as natural antioxidants with potential applications in the food, cosmetic, and pharmaceutical industries.

Antioxidants from barley husks impregnated in films of low-density polyethylene and their effect over lipid deterioration of frozen cod (Gadus morhua).

BACKGROUND: The changes in quality of cod fillets packaged in films with and without antioxidants during 12 months of frozen storage at - 20 °C were investigated in the present study. The following parameters were determined in order to study lipid hydrolysis and primary and secondary lipid oxidation in the samples during frozen storage: peroxide value, conjugated dienes, conjugated triene hydroperoxides, free fatty acids, totox value, thiobarbituric acid-reactive substances and p-anisidine value. RESULTS: Films containing antioxidants isolated from barley husks were effective in slowing down lipid hydrolysis and primary and secondary lipid oxidation processes. Secondary lipid oxidation reached maximum values in the 12th month of storage in control samples and samples packaged with antioxidant-containing film. Maximum lipid hydrolysis and lipid oxidation values for control cod samples were significantly higher than the maximum values found in samples packaged with antioxidant-containing film. CONCLUSION: The results confirm the efficacy of natural antioxidants derived from barley husks in slowing down lipid hydrolysis and increasing the oxidative stability of cod flesh. They also demonstrate the potential usefulness of natural antioxidants extracted from barley husks in the development of active packaging films for food preservation.