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Volatile fatty acids (VFA) and reducing sugars (RS) are widely used as platform molecules in biorefineries, facilitating the production of valuable biofuels and chemicals. From an environmental, economic and social perspective, third generation biomass, including macroalgae beach-cast, represents an innovative and optimal solution for the production of these commodities. This study explores the impact of ultrasound pretreatment on the invasive macroalga Rugulopteryx okamurae, aiming to produce RS and VFA through enzymatic hydrolysis and dark fermentation. Several ultrasound conditions were tested: amplitudes (0, 70-100 %), suspension volumes (300, 600 mL), and algal concentrations (4-8 %). Optimal results emerged with 100 % amplitude, 300 mL volume, and 4 % (w/v) algal concentration, leading to the maximum COD solubilization of 61.5 mg COD g-biomass-1. For enzymatic hydrolysis, the pretreated sample achieved maximum RS concentrations (0.124 g-RS g-biomass-1) with half the enzyme dosage required by the non-pretreated alga (25 vs 50 FPU g-biomass-1), implying significant economic benefits for large-scale processes. The kinetic model proposed by Romero-Vargas et al. aligned perfectly with the experimental data, obtaining higher values of all the kinetic parameters for the pretreated sample. Dark fermentation showed substantial increases in organic matter solubilization and VFA production (10.36 mg-HAc g-biomass-1) post ultrasound pretreatment: 21.1 % higher solubilization and 9.4 % increased VFA compared to non-pretreated biomass. The resulting VFA composition comprised 73 % acetic acid, 13 % propionic acid, and 8 % butyric acid. Utilization of chemical agents during sonication may further enhance overall processing yields. [ABSTRACT FROM AUTHOR]

One of the most significant dried foods is raisin, used directly as ingredients in confectionary and in the form of raisin paste used in sauces, fillings, baked goods, microwaveable coatings, and other culinary products to color them naturally. The purpose of this study is to investigate the effects of ultrasound pretreatment (53 kHz, 300 W, 30 °C, 300 s, in a mixture of 5% K2CO3+ 1% OO solution) and drying air temperatures (40–60 °C) on the drying behavior, color values, physicochemical properties (moisture content, VCC, TPC, RSC, and antioxidant capacity (DDPH)) and rehydration capacity of Sultani Çekirdeksiz grapes. Both the drying kinetic (drying time, drying rate, and effective moisture diffusivity) and the quality characteristics of grapes were significantly improved by ultrasound pretreatment (p < 0.05). In addition, the vitamin C (0.75–3.86 mg/g) and total phenolic content (1.31–1.80 mg GA/kg) of raisins were highly protected with the high drying temperature and ultrasound pretreatment. The antioxidant capacity (1.15–5.50 mM Trolox) of samples increased with drying temperature whereas the antioxidant capacity decreased with ultrasound application. The rehydration time of all samples was found around 800 min. As a result of this study, it can be said that the ultrasound application may be used successfully for drying grapes and that a greater degree of the nutritional value of the grapes can be maintained. [ABSTRACT FROM AUTHOR]

Bioethanol from cornstarch is the largest renewable liquid biofuel currently in use. However, corn is the basis of the population's diet in many countries so other feedstock must be considered. This article proposes non-conventional starch from Ramon tree (Brosimum alicastrum), a specie native to the Mesoamerican region and widely distributed in the Yucatan Peninsula, Mexico. Ultrasound has appeared as a promising green technique used to make physical, chemical, and biological processes, including enzymatic reactions, more efficient. Ultrasonic pretreatments (UL) alone and combined with commercial enzymes and enzymatic extracts of native fungi (Trametes hirsuta Bm-2) with a power of 70 W at 42 kHz, for 30 min at 45 °C, 60 °C, and 70 °C, were used. The results indicate that the pretreatment conditions do not inhibit the enzymatic activity; on the contrary, they decrease the operational temperature, giving the best results at 45 °C. All the treatments presented significantly higher dextrose equivalent values than the control without sonication. In the fermentation process, 91% efficiency was reached using the native strain Candida tropicalis PL-1, which infers yields of 314 and 235 L/ton of Ramon seed flour (RF) for samples pretreated by UL combined with α-amylase and raw enzymatic extract respectively. Based on the above, the ultrasonic treatment combined with enzymes applied to RF is outlined as an option of non-conventional starch pretreatment for the bioethanol production to avoid the use of basic food in the quest of clean energy. [ABSTRACT FROM AUTHOR]

Introduction: The present research describes the utilization of natural deep eutectic solvent in combination with ultrasound for the extraction of milk thistle polyphenols. The extracts obtained under different conditions were evaluated for their in vitro antioxidant activities and hepatoprotective activities in Albino mice (in vivo). Methods: The extraction parameters involving liquid-to-solid ratio (S/L), ethanol-to-natural deep eutectic solvent ratio (EtOH/DES), extraction time (t), and ultrasound treatment time were investigated and optimized to enhance the recovery of bioactives, their phenolic content, Trolox equivalent antioxidant capacity (TEAC), and radical scavenging capacity (RSC). Results and discussions: The extraction of milk thistle polyphenols using glucose/citric acid (1:1)-based natural deep eutectic liquid coupled with ultrasound for 1.0min under an S/L of 6.2, EtOH/DES 9, and extraction time of 120.8min offered 35.89 ± 2.29 g/100 g of crude extracts, which were three-fold higher than that by conventional solvent extraction (CSE). Each gram of milk thistle extracts thus obtained comprised 377.93 ± 6.17mg GAE of TPC and exhibited 298.70 ± 3.06 μmol TEAC and 93.16 ± 0.58 percent inhibition of DPPH free radicals. In addition, the administration of milk thistle extracts obtained as given above at 25 mg/Kg body weight in Albino mice significantly (p ≤ 0.05) improved the liver function parameters at the end of treatment (7 days). Conclusion: Overall, it was observed that NaDES in combination with medium-level ultrasound energy (700 watt) might work as a sustainable choice to enhance the recovery of bioactive phenolics from milk thistle powder without compromising their antioxidant and hepatoprotective potential. [ABSTRACT FROM AUTHOR]

In this study, we used experimental analysis and numerical simulation to describe and compare the convective drying (CD) of banana slices, without and with pretreatment with ultrasound (US) at 25 kHz. Banana slices, with an average initial thickness of about 6.60 × 10−3 m and an average diameter of about 3.01 × 10−2 m, were subjected to CD at temperatures of 60, 70, and 80°C, with air speed of 1.5 m s−1. Considering such dimensions, the one‐dimensional diffusion equation in Cartesian coordinates was numerically solved by the finite volume method, using a fully implicit formulation (direct problem). A solver with a numerical solution was developed for the direct problem. This solver was coupled to an optimizer to determine the parameters a and b of functions that relate the effective moisture diffusivity (D) with the local moisture ratio, and also to determine the convective mass transfer coefficient (h) (inverse problem), considering the shrinkage. The proposed model was used to describe the data obtained. The results revealed that the drying rate increased in samples that were subjected to pretreatment with US, for each drying temperature. The best‐simulated results were those that related D to the local moisture ratio by means of a bcosh (aMR2) function. It could be observed that pretreatment with US allowed saving of time (and consequently energy) of 28.3%, 16.0%, and 12.4% at drying temperatures of 60, 70, and 80°C, respectively. Practical applications: The main contribution of this paper is to present a solver and an optimizer to determine the mass transfer properties considering the shrinkage during convective drying of banana pieces pretreated with ultrasound by the inverse problem. With the information obtained for the mass transfer properties and the proposed numerical model with a hyperbolic cosine type function for the effective moisture diffusivity, it is possible to more accurately determine the time and, therefore, the energy savings of processing banana chips pre‐treated with ultrasound. [ABSTRACT FROM AUTHOR]

Osmotic dehydration (OD) of carrots was studied by varying the OD conditions (ultrasound as pretreatment [USP], ultrasound‐assisted OD [USOD], and OD without ultrasound [no treatment]), solute concentration (50, 60, and 70°Brix) and solid‐to‐solution ratio (1:3, 1:4, and 1:5). The osmotically dehydrated carrots obtained from the different combinations were then analyzed for solid‐gain (SG) and water loss. Color and texture measurements along with carotenoid content were also studied. Among the different solid‐to‐solution ratios (1:3, 1:4, and 1:5), samples dehydrated with 1:4 yielded the best result for different tests. USOD samples (1:4) gave significantly (p < 0.05) better results for water‐loss (68.74%) and SG (16.57%) as compared to SG of USP (12.46%) and SG of non‐treated samples (11.6%). USOD samples underwent the least amount of color change but had significantly higher values of hardness (240.38 N) than other treatments. The yield of total carotenoids was also significantly (p < 0.05) higher in the USOD samples (22.30 mg/100 g) when compared with USP (18.27 mg/100 g) and non‐treated samples (13.94 mg/100 g). The better quality of products from USOD treatment in terms of color, texture, and nutrition can make it a popular choice in the food industry for various applications. Practical applications: Osmotic dehydration (OD) is a useful technique to preserve the nutritional and sensory qualities of carrots and extend its shelf life. OD is a time‐consuming process and the rate of mass transfer from foods can be increased when OD is combined with other processes. Ultrasound (US) processing is a non‐thermal process that can be used to increase the mass transfer rate during the OD process. In the present work, US was applied as a pretreatment before carrying out the OD process and during the OD process, that is, US was applied in the osmotic solution after putting the carrot slices to see which method was better in increasing the mass transfer rate and preserving the quality of the dehydrated carrots. The findings will help in deciding the proper way for US to be applied for the OD process for carrots and can be extended to other fruits and vegetables. [ABSTRACT FROM AUTHOR]

IntroductionThe present research describes the utilization of natural deep eutectic solvent in combination with ultrasound for the extraction of milk thistle polyphenols. The extracts obtained under different conditions were evaluated for their in vitro antioxidant activities and hepatoprotective activities in Albino mice (in vivo).MethodsThe extraction parameters involving liquid-to-solid ratio (S/L), ethanol-to-natural deep eutectic solvent ratio (EtOH/DES), extraction time (t), and ultrasound treatment time were investigated and optimized to enhance the recovery of bioactives, their phenolic content, Trolox equivalent antioxidant capacity (TEAC), and radical scavenging capacity (RSC).Results and discussionsThe extraction of milk thistle polyphenols using glucose/citric acid (1:1)-based natural deep eutectic liquid coupled with ultrasound for 1.0 min under an S/L of 6.2, EtOH/DES 9, and extraction time of 120.8 min offered 35.89 ± 2.29 g/100 g of crude extracts, which were three-fold higher than that by conventional solvent extraction (CSE). Each gram of milk thistle extracts thus obtained comprised 377.93 ± 6.17 mg GAE of TPC and exhibited 298.70 ± 3.06 μmol TEAC and 93.16 ± 0.58 percent inhibition of DPPH free radicals. In addition, the administration of milk thistle extracts obtained as given above at 25 mg/Kg body weight in Albino mice significantly (p ≤ 0.05) improved the liver function parameters at the end of treatment (7 days).ConclusionOverall, it was observed that NaDES in combination with medium-level ultrasound energy (700 watt) might work as a sustainable choice to enhance the recovery of bioactive phenolics from milk thistle powder without compromising their antioxidant and hepatoprotective potential.

The present study aimed to analyze and establish an effective combination of ultrasound and immersion pretreatment processes for drying Taikor (Garcinia pendunculata Roxb.) fruits. Taikor slices were first immersed in 10 % sucrose, fructose, and glucose solution. Then, the immersed slices were treated in an ultrasonic bath at 30 °C for 10, 20, and 30 min. Drying operations were carried out at 50, 60, and 70 °C, with a fixed relative humidity of 30 %. The Page, Newton, Henderson and Pabis, and Weibull distribution models were fitted to the obtained drying data to determine the best kinetic model that effectively describes the drying properties of Taikor. After drying operations, changes in quality parameters, e.g., β-carotene, vitamin C, B vitamins, color, antioxidant activities, and microbial loads, were measured to obtain the best drying temperature and the most effective pretreatment combination with minimum loss of nutrients of the sample. Among different kinetic models, both Page and Weibull distribution models showed the best R2 values of 0.9867 and 0.9366, respectively. The chemical properties were preserved to the greatest extent possible by drying at 50 °C with glucose pretreatment. The color parameters were better preserved by fructose pretreatment. Sonication time also had profound effect on the quality parameters of dried Taikor slices. However, higher temperature drying required a shorter time for drying and exhibited better performance in microbial load reduction. This study's findings will help to establish an effective drying condition for Garcinia pedunculata fruits.

The aim of this work was to investigate the effects of ultrasonic treatment during soaking of potatoes on the physicochemical properties of starches obtained after 16 weeks of germination. The ultrasonic treatment showed a direct correlation between sprout length and ultrasonic time. The protein content decreased from 0.63 to 0.38 % and the fat content decreased significantly from 0.31 to 0.01 % after germination. The amylose content changed depending on the ultrasonic treatment, and increased from 36.27 to 40.92 % after 16 weeks of germination, which was related to the amylopectin debranching and the duration of the ultrasonic treatment. X-ray diffraction showed that the nanocrystals with hexagonal structure were not affected by the germination and the duration of ultrasonic treatment. Scanning electron microscopy showed that the surface of the starch granules was not affected by the enzymatic treatment. The sprouted potato starch resulted in films with better tensile strength and lower water vapor permeability (WVP) compared to the native potato starch films. In addition, the films produced with ultrasound stimulated potato starch exhibited better properties (high strength and low permeability), which is desirable when it comes to controlling moisture exchange between a food product and the surrounding atmosphere. • Ultrasound stimulate the germination of potatoes. • Germination has no influence on the nanocrystals structure with hexagonalarrangement that occur in potato starch. • Ultrasonic stimulation prior to potato germination increased the viscosity of the starch pastes. • Germinated potato starch reduces the water vapor permeability in thin films. [ABSTRACT FROM AUTHOR]

In this study, double enzyme hydrolysis significantly enhanced the DPP-IV inhibition rate compared to single enzyme. The α + K enzymes exhibited the highest inhibition rate. Ultrasonic pretreatment for 30 min improved the hydrolysis efficiency and DPP-IV inhibition rate, potentially due to the structural changes in hydrolysates, such as the increased surface hydrophobicity, and reduced particle size, α-helix and β-turn. Six peptides were screened and verified in vitro. QPY, WPEYL, and YPPQVM displayed competitive inhibition, while LPAAP and IPAPSFPRL displayed mixed competitive/non-competitive inhibition. The interactions between these six peptides and DPP-IV primarily occurred through hydrogen bonds, electrostatic and hydrophobic interactions. Network pharmacological analysis indicated that LPAAP might inhibit DPP-IV activity trough interactions with diabetes-related targets such as CASP3, HSP90AA1, MMP9, and MMP9. These results uncover the potential mechanism of regulating blood glucose by camel milk hydrolysates, establishing camel milk peptide as a source of DPP-IV inhibitory peptide. • Combination of double enzymatic and ultrasonication improved DPP-IV inhibition. • Six peptides were screened based on the predicted results and in vitro test. • LPAAP exhibited highest active against DPP-IV, with IC 50 values 199.66 ± 6.77 μM. • Molecular docking and network pharmacology predicted DPP-IV inhibition mechanism. [ABSTRACT FROM AUTHOR]

In order to better utilize the proteins in squid viscera (Dosidicus gigas), the effects of different pretreatments on the degree of hydrolysis (DH) and volatile compounds of hydrolysates were studied. The DH was used as an indicator to select alkaline protease as the optimal protease from 8 types of proteases. The hydrolysis conditions of alkaline protease and the flavor of the hydrolysates were investigated through single-factor, response surface methodology, and pretreatment-assisted hydrolysis experiments. The results showed that alkaline protease had the highest DH (42.08 ± 0.58%), with enzyme dosage of 1.5%, hydrolysis temperature of 45 °C, hydrolysis time of 5 h, and liquid-solid ratio of 4:1. The DH of the ultrasound group was significantly higher than other groups, with the highest DH (45.67 ± 0.34%) after ultrasound for 40 min (U40). The proportion of molecular weight < 1 kDa and the content of free amino acids (1613.64 mg/100 g) were the highest at U40. The electronic nose results indicated that the composition of organic sulfur and aliphatic compounds in U40 showed significant differences compared to other products. The U40 sample had the highest type and content of volatile compounds (especially benzaldehyde), which was more conducive to the volatilization of flavor substances. In conclusion, U40 pretreatment can effectively improve the DH and flavor of hydrolysates. • Hydrolysis conditions of squid viscera were optimized. • Effects of heat and ultrasound pretreatments on hydrolysis were investigated. • Ultrasound pretreatment enhanced the hydrolysis efficiency. • Ultrasound pretreatment improved the flavor of squid viscera hydrolysates. [ABSTRACT FROM AUTHOR]

• US-OH method was proposed as the optimal plant bioactive extraction technique. • EY, TPC, and antioxidant activity of US-OH extract were higher than other methods. • US-OH and MW-OH methods showed an improvement in the extract quality compared to the HAE method. The present study was carried out to investigate and optimize the recovery of Burdock (Arctium lappa L.) root extract (BRE) using Ohmic-assisted (OH) extraction method with ultrasonic (US-OH) and microwave (MW-OH) pretreatments. Initially the optimized OH condition was obtained with the aim of maximizing the extraction efficiency and total phenol content. Then, the effect of pretreatment time (20, 40 and 60 min), ultrasonic amplitude (50 and 100 %) and temperatures (30, 40 and 50 °C) in US-OH, and powers (100, 300 and 450 W) in MW-OH were investigated. Finally, optimized OH, US-OH, and MW-OH extraction methods were compared with the heat assisted extraction method (HAE). The results showed that all the main and interaction effects were significant in OH, US-OH, and MW-OH extraction methods (p < 0.05) and only the interaction effects on total phenolic content (TPC) were not significant in the OH method (p > 0.05). The voltage gradient equal to 12.8 V/cm, extraction time equal to 20.72 min and extraction temperature equal to 50 °C were obtained as optimal conditions in the OH extraction of BRE. Ultrasonic amplitude, extraction temperature and ultrasonic time 100 %, 50 °C and 40 min respectively were obtained as the optimum US-OH extraction method. According to the results of chemical compounds, microbial and morphological assays, extraction using pretreatment methods of ultrasound, microwave in ohmic heating, respectively, showed an improvement in the quality of the extraction compared to the conventional (HAE) method. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Oyster hydrolysate with aroma and umami was efficiently prepared. • The fingerprints of oyster compounds were analyzed by GC–MS and GC-IMS. • 19 key aroma compounds were identified in oyster hydrolysates from UP-NF. • UP-NF could increase the release of umami substances. In the study, an efficient protease Neutrase®-Flavourzyme® (NF) was screened to prepare the umami-aroma flavor oyster hydrolysate. The effect of protease and ultrasonic pretreatment (UP) assisted by the optimal protease on the flavor substances was investigated. The results demonstrated that the optimal UP-NF (450 W) showed a higher amino acid nitrogen content of 0.34 g/100 mL compared to the NF, and 19 major aroma compounds including octanal, decanal, nonanal, benzaldehyde, 2-undecanone, and 1-octen-3-ol were obtained. Additionally, the free amino acid and fatty acid spectrum indicated that the formation of flavor compounds was primarily due to the oxidation of linoleic and linolenic acids and the degradation of amino acids. Furthermore, taste analysis proved that increased umami and saltiness resulted from the accelerated release of Glu, Asp and 5′-IMP. Overall, UP-NF proved to be an effective method for producing umami-aroma flavor, facilitating further processing of oyster products for the application. [ABSTRACT FROM AUTHOR]

• Combined ultrasound-assisted immersion pretreatments were used prior Taikor drying. • Page and Weibull distribution models fitted the best to explain drying kinetics. • Immersion pretreatment by 10% glucose solution retained the nutritional quality. • Products' quality gradually degraded as the drying temperature raised from 50 to 70 °C. • Higher treatment time and drying temperature showed better microbial load reduction. The present study aimed to analyze and establish an effective combination of ultrasound and immersion pretreatment processes for drying Taikor (Garcinia pendunculata Roxb.) fruits. Taikor slices were first immersed in 10 % sucrose, fructose, and glucose solution. Then, the immersed slices were treated in an ultrasonic bath at 30 °C for 10, 20, and 30 min. Drying operations were carried out at 50, 60, and 70 °C, with a fixed relative humidity of 30 %. The Page, Newton, Henderson and Pabis, and Weibull distribution models were fitted to the obtained drying data to determine the best kinetic model that effectively describes the drying properties of Taikor. After drying operations, changes in quality parameters, e.g., β-carotene, vitamin C, B vitamins, color, antioxidant activities, and microbial loads, were measured to obtain the best drying temperature and the most effective pretreatment combination with minimum loss of nutrients of the sample. Among different kinetic models, both Page and Weibull distribution models showed the best R2 values of 0.9867 and 0.9366, respectively. The chemical properties were preserved to the greatest extent possible by drying at 50 °C with glucose pretreatment. The color parameters were better preserved by fructose pretreatment. Sonication time also had profound effect on the quality parameters of dried Taikor slices. However, higher temperature drying required a shorter time for drying and exhibited better performance in microbial load reduction. This study's findings will help to establish an effective drying condition for Garcinia pedunculata fruits. [ABSTRACT FROM AUTHOR]