Lacticaseibacillus rhamnosus encapsulated cross-linked Keratin-Chitosan hydrogel for removal of patulin from apple juice.

In this study, we developed a hydrogel from cross-linked keratin and chitosan (KC) to remove patulin (PAT) from apple juice. We explored the potential of incorporating Lactobacillus rhamnoses into the KC hydrogel (KC-LR) and tested its effectiveness in removing PAT from simulated juice solutions and real apple juice. The KC hydrogel was developed through a dynamic disulfide cross-linking reaction. This cross-linked hydrogel network provided excellent stability for the probiotic cells, achieving 99.9 % immobilization efficiency. In simulated juice with 25 mg/L PAT, the KC and KC-LR hydrogels showed removal efficiencies of 85.2 % and 97.68 %, respectively, using 15 mg mL-1 of the prepared hydrogel at a temperature of 25 °C for 6 h. The KC and KC-LR hydrogels achieved 76.3 % and 83.6 % removal efficiencies in real apple juice systems, respectively. Notably, the encapsulated probiotics did not negatively impact the juice quality and demonstrated reusability for up to five cycles of the PAT removal process.

Natural deep eutectic solvents for Ultrasonic-Assisted extraction of nutritious date Sugar: Molecular Screening, Experimental, and prediction.

The aim of this study is to develop an environmentally friendly and effective method for the extraction of nutritious date sugar using natural deep eutectic solvents (NADES) and ultrasound-assisted extraction (USAE). The careful design of a suitable NADES-USAE system was systematically supported by COSMO-RS screening, response surface method (RSM) and artificial neural network (ANN). Initially, 26 natural hydrogen bond donors (HBDs) were carefully screened for sugar affinity using COSMO-RS. The best performing HBDs were then used for the synthesis of 5 NADES using choline chloride (ChCl) as HBA. Among the synthesized NADES, the mixture of ChCl, citric acid (CA) and water (1:1:1 with 20 wt% water) resulted in the highest sugar yield of 78.30 ± 3.91 g/100 g, which is superior to conventional solvents such as water (29.92 ± 1.50 g/100 g). Further enhancements using RSM and ANN led to an even higher sugar recovery of 87.81 ± 2.61 g/100 g, at conditions of 30 °C, 45 min, and a solvent to DFP ratio of 40 mL/g. The method NADES-USAE was then compared with conventional hot water extraction (CHWE) (61.36 ± 3.06) and showed 43.1% higher sugar yield. The developed process not only improves the recovery of the nutritious date sugar but also preserves the heat-sensitive bioactive compounds in dates, making it an attractive alternative to CHWE for industrial utilization. Overall, this study shows a promising approach for the extraction of nutritive sugars from dates using environmentally friendly solvents and advanced technology. It also highlights the potential of this approach for valorizing underutilized fruits and preserving their bioactive compounds.

Green dispersants for oil spill response: A comprehensive review of recent advances.

Green dispersants are so-called "green" because they are renewable (from bio-based sources), non-volatile (from ionic liquids), or are from naturally available solvents (vegetable oils). In this review, the effectiveness of different types of green dispersants, namely, protein isolates and hydrolysates from fish and marine wastes, biosurfactants from bacterial and fungal strains, vegetable-based oils such as soybean lecithin and castor oils, as well as green solvents like ionic liquids are reviewed. The challenges and opportunities offered by these green dispersants are also elucidated. The effectiveness of these dispersants varies widely and depends on oil type, dispersant hydrophilicity/hydrophobicity, and seawater conditions. However, their advantages lie in their relatively low toxicity and desirable physico-chemical properties, which make them potentially ecofriendly and effective dispersants for future oil spill response.

ZIF-8 as support for enhanced stability of immobilized lipase used with a thermoresponsive switchable solvent to simplify the microalgae-to-biodiesel process.

The zeolitic imidazole framework (ZIF)- 8 was tested as a support to enhance the stability of immobilized lipase. The lipase immobilized on ZIF-8, through surface attachment and encapsulation, was used for the simultaneous cell disruption and oil extraction from untreated, wet microalgal paste. The successful attachment of the enzyme to ZIF-8 was confirmed via Fourier-transform infrared spectroscopy. The attachment of the enzyme did not significantly affect the crystallinity or morphology of ZIF-8 crystals. The encapsulated lipase@ZIF-8 system showed higher stability than the adsorbed system, due to its reduced vulnerability to leaching. After five cycles, the encapsulated lipase@ZIF-8 retained 32% of its initial activity, whereas, for the adsorbed lipase@ZIF-8, it reduced to 21%. An increase in methanol amount greater than 0.2 mL was shown to have a negative effect on enzyme activity. The fatty acid methyl ester yield increased significantly with an increase in the extraction- duration (up to 3 h), after which the effect faded until 5 h, after which the equilibrium yield was reached. Changing the composition of the thermoresponsive switchable solvent (TSS) showed that a higher FAME yield could be achieved by increasing the percentages of Ionic Liquid (IL) and polypropylene glycol and reducing the water percentage. Further studies are needed to optimize the TSS composition and its effects on the process.

Comparative study of lactic acid production from date pulp waste by batch and cyclic-mode dark fermentation.

Biowaste valorization into lactic acid (LA) by treatment with indigenous microbiota has recently gained considerable attention. LA production from date pulp waste provides an opportunity for resource recovery, reduces environmental issues, and possibly turns biomass into wealth. This study aimed to compare the performance of batch and cyclic fermentation processes in LA production with and without enzymatic pretreatment. The fermentation studies were conducted in the absence of an external inoculum source (relying on indigenous microbiota) and without the addition of nutrients. The highest LA volumetric productivity (3.56 g/liter/day), yield (0.07 g/g-TS), and concentration (21.66 g/L) were attained with enzymatic pretreated date pulp in the cyclic-mode fermentation at the optimized conditions. The productivity rate of LA was enhanced in the cyclic-mode as compared to the batch process. Enzymatic pretreatment increased the digestibility of cellulose that led to higher LA yield. An Artificial Neural Network model was developed to optimize the process parameters and to predict the LA concentration from date pulp waste in both fermentation processes. The main advantage of the ANN approach is the ability to perform quick predictions without resource-consuming experiments. The model predicted optimal conditions well and demonstrated good agreement between experimental and predicted data.

Techno-Economic Assessment of Whey Protein-Based Plastic Production from a Co-Polymerization Process.

Bio-based plastics, produced from natural and renewable sources, have been found to be good replacers to petroleum-based plastics. However, economic analyses have not been carried out for most of them, specifically those from whey. In this study, a techno-economic assessment of the industrial-scale production of plastics from whey protein is carried out considering two different scenarios: (1) low-cost dairy waste whey (DWP) and (2) purchased whey protein concentrate (WPC), as feedstocks, using SuperPro Designer software. Key economic indicators such as operating cost, capital investment, annual revenue, payback time, and return-on-investment (ROI), were analyzed. Sensitivity analyses of different parameters were performed to account for market fluctuations and other uncertainties, using Scenario 2 as the base case. Results showed that both scenarios have the capacity of producing over 3200 metric tons/year (t/yr) (or 5.5 t/batch) of plastic. With the unit selling price of plastic set at $7,000/t, both the scenarios showed profitable outcomes with the plant's payback time of 3.7 and 2.4 years, and ROI of 27.1% and 42.2%, for Scenario 1 and Scenario 2, respectively. Sensitivity analyses showed that the unit plastic selling price was the most sensitive parameter, followed by the amount of feedstock WPC, and the number of batches.

Sorption and removal of crude oil spills from seawater using peat-derived biochar: An optimization study.

Bio-based sorbents are preferred over chemical-based methods for the clean-up of crude oil spills in marine environments because bio-based sorbents are more environmentally friendly. This study evaluates the use of peat-derived biochar (PB) as a bio-sorbent for the sorption and removal of crude oil spills from synthetic seawater. Experiments were designed to determine the effect of four operating factors (PB/crude oil contact time, PB dosage, oil dosage, and temperature) on two performance indicators (crude oil sorption capacity of PB, S, and oil removal efficiency, R%). Regression models containing linear, quadratic, and two-way interaction terms were developed to predict S and R% from the four factors. Response surface methodology (RSM) was employed to identify the optimum conditions for the sorption and removal of crude oil from seawater. The performance indicators were predicted with a high degree of accuracy, i.e. with coefficient of determination (R2) values exceeding 90%. The optimum values of S and R% were estimated to be 32.5 g of crude oil/g of sorbent and 91.2% respectively. These optimum values were attained after 70 min of PB/crude oil contact time and at a temperature of 45 °C. The spent sorbent maintained its performance after three cycles of regeneration and reuse, suggesting that the material is reusable.

Preparation and Characterization of Whey Protein-Based Polymers Produced from Residual Dairy Streams.

The wide use of non-biodegradable, petroleum-based plastics raises important environmental concerns, which urges finding alternatives. In this study, an alternative way to produce polymers from a renewable source-milk proteins-was investigated with the aim of replacing polyethylene. Whey protein can be obtained from whey residual, which is a by-product in the cheese-making process. Two different sources of whey protein were tested: Whey protein isolate (WPI) containing 91% protein concentration and whey protein concentrate (WPC) containing 77% protein concentration. These were methacrylated, followed by free radical polymerization with co-polymer poly(ethylene glycol) methyl ether methacrylate (PEGMA) to obtain polymer sheets. Different protein concentrations in water (11-14 w/v%), at two protein/PEGMA mass-ratios, 20:80 and 30:70, were tested. The polymers made from WPI and WPC at a higher protein/PEGMA ratio of 30:70 had significantly better tensile strength than the one with lower protein content, by about 1-2 MPa (the best 30:70 sample exhibited 3.8 ± 0.2 MPa and the best 20:80 sample exhibited 1.9 ± 0.4 MPa). This indicates that the ratio between the hard (protein) and soft (copolymer PEGMA) domains induce significant changes to the tensile strengths of the polymer sheets. Thermally, the WPI-based polymer samples are stable up to 277.8 ± 6.2 °C and the WPC-based samples are stable up to 273.0 ± 3.4 °C.

RF microalgal lipid content characterization.

Most conventional techniques for the determination of microalgae lipid content are time consuming and in most cases are indirect and require excessive sample preparations. This work presents a new technique that utilizes radio frequency (RF) for rapid lipid quantification, without the need for sample preparation. Tests showed that a shift in the resonance frequency of a RF open-ended coaxial resonator and a gradual increase in its resonance magnitude may occur as the lipids content of microalgae cells increases. These response parameters can be then calibrated against actual cellular lipid contents and used for rapid determination of the cellular lipids. The average duration of lipid quantification using the proposed technique was of about 1 minute, which is significantly less than all other conventional techniques, and was achieved without the need for any time consuming treatment steps.

A review of enzymatic transesterification of microalgal oil-based biodiesel using supercritical technology.

Biodiesel is considered a promising replacement to petroleum-derived diesel. Using oils extracted from agricultural crops competes with their use as food and cannot realistically satisfy the global demand of diesel-fuel requirements. On the other hand, microalgae, which have a much higher oil yield per hectare, compared to oil crops, appear to be a source that has the potential to completely replace fossil diesel. Microalgae oil extraction is a major step in the overall biodiesel production process. Recently, supercritical carbon dioxide (SC-CO(2)) has been proposed to replace conventional solvent extraction techniques because it is nontoxic, nonhazardous, chemically stable, and inexpensive. It uses environmentally acceptable solvent, which can easily be separated from the products. In addition, the use of SC-CO(2) as a reaction media has also been proposed to eliminate the inhibition limitations that encounter biodiesel production reaction using immobilized enzyme as a catalyst. Furthermore, using SC-CO(2) allows easy separation of the product. In this paper, conventional biodiesel production with first generation feedstock, using chemical catalysts and solvent-extraction, is compared to new technologies with an emphasis on using microalgae, immobilized lipase, and SC-CO(2) as an extraction solvent and reaction media.