Hydrolysate Concentration Research Articles

Exploration on antifreeze potential of thawed drip enzymatic hydrolysates on myofibrillar proteins in pork patties during freeze-thaw cycles

This study explored using small molecular weight hydrolysates from enzymolyzed thawed drip as cryoprotectants to preserve myofibrillar protein quality in pork patties during freeze-thaw cycles. Hydrolysates were added at 0.36 %, 0.72 %, and 1.4 % concentrations, compared to a control with deionized water and a positive control with sorbitol and sucrose. Results indicated that thawed drip hydrolysates significantly reduced thawing loss and cooking loss. Moreover, the color deterioration during the 3rd and 6th freeze-thaw cycles was delayed. Myofibrillar protein denaturation and oxidation in the experimental groups were inhibited, shown by decreased surface hydrophobicity, reduced carbonyl groups and protein surface roughness, and increased free sulfhydryl groups, α-helix content, and protein particle height. The highest hydrolysate concentration (1.4 %) provided the most benefits, performing comparably to the positive control. Correlation analysis confirmed that hydrolysates enhanced both myofibrillar protein and pork quality, offering a promising approach to improve meat resilience against freeze-thaw conditions.

PBPK modelling for the evaluation of drug-drug interaction between meropenem and valproic acid.

The present study aimed to quantitatively investigate the potential drug-drug interaction (DDI) mechanism between meropenem (MEPM) and valproic acid (VPA). In the present study, we firstly developed a physiologically based pharmacokinetic (PBPK) model of MEPM and VPA. The verified PBPK model was then used to quantitatively investigate the potential DDI between MEPM and VPA. The effect of genetic polymorphisms of acylpeptide hydrolase (APEH) on DDI was also evaluated. In our simulation, the plasma concentration of hydrolysate of VPAG decreased to 63% when combined with MEPM. Total plasma concentration of VPA before carbapenem use was 53.61 mg/L, whereas it was 45.42 mg/L during carbapenem use. The inhibition of hydrolysis of VPAG by MEPM alone could not result in a rapid and substantial decrease in the plasma concentration of VPA. Parameter sensitivity analysis showed that the changes of absorption played an important role in the maximum plasma concentration (Cmax) of VPA, whereas area under the plasma concentration-time profile (AUC) was more susceptible to elimination changes. In addition, a decrease in APEH activity had little impact on the plasma pharmacokinetics of VPA. The DDI between MEPM and VPA might be a comprehensive result of multiple factors. On the basis of our simulation, interval medication of MEPM injection and VPA immediate release tablet at 4-6h timed interval was recommended, or intravenous administration of VPA solution was preferred when combination regimen was necessary in a clinical setting.

Determination of Sugar Concentrations in Aqueous Solution Using Multivariate Predictions Based on 1H‐NMR Spectroscopy

AbstractRenewable chemicals from carbohydrate‐rich wastes, like furfural and 5‐hydroxymethylfurfural (HMF), are gaining prominence as alternatives to petroleum‐based resources. Assessing the suitability of biomass as feedstock for furfural and HMF production requires knowledge of its composition. This study focuses on developing and validating predictive models for individual sugar concentrations in hydrolysates using quantitative 1H NMR data. Utilizing partial least square (PLS) regression, the dataset includes 137 NMR spectra of multi‐component sugar standards (arabinose, fructose, galactose, glucose, mannose, maltose, sucrose, and xylose). The best‐performing model achieved an R2 of 0.987–0.999 and RMSECV of 0.37–1.56 mM and is based on the non‐overlapping area of the NMR spectrum. Real‐world samples were used for validation, resulting in predicted sugar concentrations with a mean standard deviation of 0.5 mM. This high accuracy and streamlined analysis process make these models practical for quantifying large sample sets, showcasing the reliability and accessibility of extracting statistical information from H‐NMR data.

EFFECT OF FISH PROTEIN HYDROLYSATE ON GROWTH, YIELD AND STORABILITY OF SOME FEMALE CUCUMBER HYBRIDS (Cucumis Sativus L) GROWN IN PLASTIC HOUSE IN BASRA

General Background: Cucumber (Cucumis sativus L.) is a widely cultivated vegetable, valued for its nutritional and economic significance. Specific Background: The application of biostimulants, such as fish protein hydrolysate, has gained attention for enhancing plant growth and yield. However, the impact of varying concentrations of fish protein hydrolysate on different cucumber hybrids remains underexplored. Knowledge Gap: Despite existing research on biostimulants, the specific effects of fish protein hydrolysate on hybrid cucumber performance, particularly in unheated plastic houses, are inadequately documented. Aims: This study aimed to evaluate the effects of different concentrations of fish protein hydrolysate on the growth and yield of three cucumber hybrids ("Super Faris," "Ballistic," and "Darina") during the winter agricultural season of 2023/2024. Results: Conducted in a randomized complete block design with six factorial treatments and three replicates, the results indicated that the "Darina" hybrid significantly outperformed the other hybrids in key growth parameters, including plant height, stem diameter, leaf count, fruit number, fruit weight, individual plant yield, total yield, and total dissolved solids. Additionally, concentrations of fish protein hydrolysate at 2 and 4 ml L-1 demonstrated significant benefits over control treatments for most vegetative and yield indicators, although no effect on vitamin C content was observed. Novelty: This study provides new insights into the synergistic effects of hybrid selection and biostimulant application in cucumber cultivation. Implications: The findings suggest that the strategic application of fish protein hydrolysate can enhance cucumber production, highlighting its potential as a sustainable agricultural practice to improve crop yield and quality.

Exploring the potential of fibrinogen hydrolysates as enhancers for myofibrillar protein gelation: Insights into molecular assembly behavior

This study explored the use of pig blood fibrinogen hydrolysates, enzymatically hydrolyzed with trypsin and flavorzyme, to enhance myofibrillar protein gels, addressing issues like poor gel strength and water loss in meat products. By incorporating varying concentrations of fibrinogen hydrolysates into myofibrillar proteins, heat-induced gels were prepared. The composite gels showed improved textural properties, rheological characteristics and water-holding capacity. Scanning electron microscopy and atomic force microscopy analyses revealed a uniform, dense surface and an orderly internal structure in the composite gels. The study also noted decreased α-helix and random coil and increased β-sheet and β-turn contents, indicating a more ordered secondary structure. Hydrophobic interactions and disulfide bonds were identified as key factors in enhancing gelation, and a model was proposed to explain these molecular effects. This research demonstrates a potential of fibrinogen hydrolysates to improve quality and structure of myofibrillar protein gels designed for high-quality meat products.

Effect of Chicken Feather Hydrolysate on Growth of Spinach through Soil Amendment Method: Unraveling A Potential Liquid Biofertilizer

The study aims to investigate the effectiveness of chicken feather hydrolysate for promoting the growth of Spinacia oleracea L., a commonly consumed leafy green vegetable. An earlier isolated and identified keratinolytic bacterial species Bacillus tropicus was utilized for the preparation of chicken feather hydrolysate through submerged fermentation. Minimal media which was supplemented with chicken feather was used for the preparation of hydrolysate. The bacterial strain degraded chicken feather within 4 days of incubation after which the feather hydrolysate was collected and tested to check plant growth promoting activity through the seed germination trials and greenhouse study. Upon characterization of feather hydrolysate, it was found that the hydrolysate was a cocktail of Nitrogen, Phosphorus and Potassium (NPK) as well as other micro elements needed for plant growth. Four different concentrations of feather hydrolysate were employed for both the seed germination and greenhouse study which ranged from 25% (v/v), 30% (v/v), 35% (v/v) and 40% (v/v) including a control group (CN) which was not supplemented with feather hydrolysate. The hydrolysate supplementation brought about plant growth in all the four test concentrations with 35% (v/v) giving the highest result of 14 cm and 27.6 mg/g for tested parameters like plumule length and total chlorophyll content, respectively. The same concentration supported maximum seed germination and highest radicle extension for the germination studies as well. This study investigates the efficacy of chicken feather hydrolysate in promoting spinach growth, elucidating its potential as a fertilizer.

Assessment of plant- and microbial-derived protein hydrolysates as sustainable for fetal bovine serum in seafood cell culture media

This study seeks to explore alternatives by substituting or reducing the conventional 10% serum concentration in zebrafish embryonic stem cell (ESC) growth media with protein hydrolysates sourced from peas, mushrooms, yeast, and algae. Notably, algae exhibited the highest protein content, optimal amino acid balance, and favorable functional properties. When applied at concentrations ranging from 1 to 10 mg/mL, all protein hydrolysates demonstrated pro-apoptotic effects and inhibited cell growth, particularly when used in conjunction with 10% serum. However, concentrations ranging from 0.001 to 0.1 mg/mL displayed anti-apoptotic properties and promoted cell proliferation. The study found that media containing 1% or 2.5% serum, along with 0.01 mg/mL of protein hydrolysates, supported cell growth effectively. Lactate Dehydrogenase (LDH) Activity served as an indicator of cell health and integrity under the specified conditions of protein hydrolysate supplementation. Cells cultured in serum-free media exhibited significantly decreased cell membrane integrity (P < 0.05) compared to those in regular media or media containing low serum (1% and 2.5%) along with low concentrations (0.01 mg/mL) of protein hydrolysates. Furthermore, analysis of Greenhouse Gas emissions (GHG) suggested that media formulations containing 1% serum combined with low concentrations of protein hydrolysates present a sustainable approach for cell-based seafood production.

Hydrolysates from cauliflower and artichoke industrial wastes as biostimulants on seed germination and seedling growth: a chemical and biological characterization.

Cauliflower (Brassica oleracea L.) and globe artichoke (Cynara scolymus L.) are vegetables with a high waste index mainly related to stems and leaves. In this study, enzymatic hydrolysates obtained from these wastes were proposed to be used as plant biostimulants. Life cycle assessment methodology was also applied to evaluate environmental performances related to cauliflower and artichoke byproducts. Hydrolysates (HYs) were chemically and biologically characterized. Amino acids, organic acids, amines, polyols, mineral elements, phenols, tannins, flavonoids and sulfur compounds were identified and quantified by means of NMR, inductively coupled plasma mass spectrometry and UV-visible analyses. Cauliflower leaf and flower HYs showed the highest concentration of free amino acids, whereas stems showed the highest concentration of Ca. Regarding artichoke, asparagine, glutamine and aspartic acid were exclusively detected in stems, whereas artichoke leaves showed the highest Mg and Mn levels together with the highest antioxidant activity. The HYs diluted in water were tested as biostimulants. The impacts of five concentrations of HYs (0.00, 0.28, 0.84, 2.52 and 7.56 g L-1) on seed germination and early seedling growth of crimson clover, alfalfa, durum wheat and corn were investigated. The application of artichoke biostimulant (0.28 g L-1) positively influenced the coefficient of velocity of germination in alfalfa, crimson clover and durum wheat, whereas cauliflower biostimulant significantly improved corn germination speed. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Sustainable succinic acid production from lignocellulosic hydrolysates by engineered strains of Yarrowia lipolytica at low pH

Succinic acid (SA) is a valuable C4 platform chemical with diverse applications. Lignocellulosic biomass represents an abundant and renewable carbon resource for microbial production of SA. However, the presence of toxic compounds in pretreated lignocellulosic hydrolysates poses challenges to cell metabolism, leading to inefficient SA production. Here, engineered Yarrowia lipolytica Hi-SA2 was shown to utilize glucose and xylose from corncob hydrolysate to produce 32.6 g/L SA in shaking flasks. The high concentration of undetoxified hydrolysates significantly inhibited yeast growth and SA biosynthesis, with furfural identified as the key inhibitor. Through overexpressing glutathione synthetase encoding gene YlGsh2, the tolerance of engineered strain to furfural and toxic hydrolysate was significantly improved. In a 5-L bioreactor, Hi-SA2-YlGsh2 strain produced 45.34 g/L SA within 32 h, with a final pH of 3.28. This study provides a sustainable process for bio-based SA production, highlighting the efficient SA synthesis from lignocellulosic biomass through low pH fermentation.

Optimized medium composition in Physalis alkekengi callus culture altered nitric oxide level for inducing antioxidant enzyme activities and secondary metabolites

Physalis alkekengi L. is a valuable medicinal plant from the Solanaceae family and has multiple therapeutic applications. This study aimed to develop an optimized protocol for callogenesis in P. alkekengi to obtain friable calluses with high biomass. The effect of different concentrations of picloram, casein hydrolysate (CH), basal media (Murashige and Skoog (MS) and Gamborg (B5)), and static magnetic field (SMF) were investigated on the callus induction and growth, signaling molecules, and enzymatic and non-enzymatic antioxidants. Results showed that CH (200 mgL−1) and SMF4 mT for 90 min increased callus induction and fresh weight in P. alkekengi, while different concentrations of picloram reduced callogenesis. Hypocotyl explants showed various callogenesis and metabolic responses depending on the basal medium type. The 2B5 medium supplied with CH 200 (mgL−1) induced friable and cream calluses with high biomass (0.62 g) compared to the MS medium (control). The maximum activity of superoxide dismutase and catalase activities was identified in the 2B5 medium and peroxidase in the 2MS medium. The highest total phenolic (129.44 µg g−1DW) content and phenylalanine-ammonia lyase activity were obtained in the 2MS medium, and total withanolides (49.86 µg g-1DW) and DPPH radical scavenging activity were observed in the 2B5 medium. The 2MS medium boosted the hydrogen peroxide and nitric oxide levels, while their contents alleviated in the 2B5 medium, although these parameters were higher than the control. The findings of this study suggest that an effective protocol for successful callogenesis in P. alkekengi and the nutrient composition of culture medium by affecting the level of signaling molecules can control the antioxidant defense system and callus growth.

Effect of zeatin and casein hydrolysate on in vitro asymbiotic germination of immature seeds of Vanilla planifolia Jacks ex Andrews (Orchidaceae)

The germination of Vanilla planifolia seeds under natural environmental conditions is very low (0.1 %) because of specific mycorrhizal requirements. Therefore, the species is typically propagated spending vegetative using stem cuttings. Thus, all cultivated plants are genetically identical and susceptible to multiple abiotic and biotic stressors. Artificial propagation from seeds is difficult for most terrestrial orchids native to temperate regions, and V. planifolia is no exception. As propagation from the seeds of this species has low success rates, in this study, an effective reproducible protocol for the in vitro asymbiotic germination of Vanilla planifolia seeds was established. For this purpose, the effects of three asymbiotic culture media on seed germination and seedling development of Vanilla planifolia [Murashige and Skoog (MS), Vacin and Went (VW), Knudson ‘C’ (KC)] were tested, two zeatin concentrations (Z = 0.25 and 0.50 mg L−1), two concentrations of casein hydrolysate (CH=50 and 500 mg L−1), and two combinations of these (Z = 0.25 mg L−1 + CH=250 mg L−1) and (Z = 0.50 mg L−1 + CH=500 mg L−1). The highest germination rate (74.5%) was recorded for the treatment with MS salts at a quarter strength supplemented with 500 mg L−1 of CH. All the seeds that germinated under this treatment showed high survival and vigorous seedling growth. In contrast, in the treatment with MS salts at a quarter strength supplemented with combination of CH and Z (CH=500 mg L−1 + Z = 0.50 mg L−1) resulted in the production of calluses (53 %).

Bioenergy feedstock production in Chlamydomonas reinhardtii (microalgae) cultivated under mixotrophic growth with cellulose hydrolysate from agricultural waste.

In the present study, cellulose purified from finger millet agricultural waste is subjected to enzymatic hydrolysis, and the hydrolysate (predominantly glucose) is used as a carbon source supplement in the media for the mixotrophic growth of Chlamydomonas reinhardtii. Interestingly, a switch between excess starch production and excess lipid (triacylglycerols, TAG) production occurs by a small change in hydrolysate concentration in the media. Starch production increased 4.5-fold with respect to the photoautotrophic control, with a glucose concentration of 3mg/mL in the media after hydrolysate addition. This culture had TAG production enhancement by 1.5-fold. However, mixotrophic cultivation with 4mg/mL glucose concentration in the media with hydrolysate addition resulted in TAG productivity enhancement by 4.2-fold compared to control and starch amount increase of 1.3-fold. The organic carbon source (glucose) and the inorganic carbon source (citrate ions) in the hydrolysate together played a role in this delicate switching between starch and lipid pathways. Proteins, starch, and TAG molecules are analyzed in the microalgal cells grown under different conditions with FTIR spectroscopy, a rapid, high-throughput method of biomolecular estimation. High-resolution single-cell AFM studies of the cell wall structure reveal enhanced corrugations in surface morphology during mixotrophic growth with cellulose hydrolysate, illustrating an adaptive mechanism with improved mechanical stress management. Lipid droplet morphology at the single-cell level points to two distinct mechanisms of lipid accumulation: one in which the lipids are segregated as droplets, and the other in which lipid molecules are uniformly dispersed in the cytosol as unresolved, ultra-small droplets. The present study therefore analyzes both the bulk and the single-cell level changes when cellulose hydrolysate is used as a carbon source for Chlamydomonas reinhardtii mixotrophic cultivation, which serves a four-fold purpose: value from waste, fixation of atmospheric CO2, production of lipids for biodiesel, and starch for bioethanol.

Production of thermostable recombinant cutinase using mixed food waste: A sustainable approach toward environmental remediation

Recently, there has been a significant surge in the utilization of single-use plastics. Cost-effective degradation of plastics is imperative to reduce the ecological burden. This study explores the overproduction and characterization of a PET (Polyethylene terephthalate) a degrading enzyme, cutinase, in the E. coli BL21 (DE3) expression system. Furthermore, this research delves into the utilization of mixed food waste (MFW) as a sustainable substrate for the production of Cutinase, replacing commercial glucose. The newly isolated strain, Aspergillus terreus, showed the highest glucoamylase activity of 76.10 ± 3.10 U/g. The enzymatic hydrolysis of mixed food waste resulted in 50 ± 0.4 g/L of glucose, used as feedstock for cutinase production. The crude enzyme activity was evaluated to be 11.64 U/mg, and a further 14.11-fold purification was achieved through IMAC. The purified recombinant enzyme showed its maximum activity at 70℃ and pH 7. The metal ion Na+ increased the enzyme activity by 26 % while Zn+2 significantly inhibited the same (47 % inhibition); other ions had little or no effect. Taguchi’s optimization of five variables showed that the concentration of food waste hydrolysate has the maximum impact on enzyme production. The treatment of commercially available PET bottles using the purified enzyme showed characterizable surface degradation effects. This is the first time food waste hydrolysate was used as a sole carbon source to produce recombinant cutinase. This approach can potentially pave the way for sustainable biorefinery and waste management.

Enhanced production of gamma-aminobutyric acid in fermented carrot juice by utilizing pectin hydrolysate derived from pomegranate waste.

In this study, a functional fermented beverage enriched with gamma-aminobutyric acid (GABA) was produced. To achieve this, the prebiotic abilities of pectin obtained from pomegranate peel and its enzymatic hydrolysates were evaluated. Additionally, a functional fermented beverage enriched with GABA was produced by fermenting carrot juice with pectin hydrolysates. First, pectin was obtained at a yield of 8.91% from pomegranate peels. Pectinase-catalyzed hydrolysis of the obtained pectin was applied using different enzyme concentrations and hydrolysis times, and the effect of these hydrolysates on the growth of Levilactobacillus brevis was determined. Although the Fourier transform infrared (FT-IR) spectra of the resulting hydrolysates were similar, their degree of esterification compared to that of pectin was statistically different (p < .05). Considering the viability analysis and GABA production of L. brevis in the liquid medium supplemented with pectin or its hydrolysate, the hydrolysate obtained by treatment with 400 μL enzyme for 2 h and having a high glucose content (216.80 mg/100 g) was selected for application in fermented carrot juice. During fermentation (24, 48, and 72 h), a remarkable change was observed, especially in the amounts of lactic acid and malic acid, while the amount of GABA in carrot juice varied between 25 and 46 mg/mL and increased with the increase in hydrolysate concentration. It was observed that the total phenolic content and antioxidant activity of carrot juice were highly affected by the hydrolysate concentration. This study demonstrated that pectin hydrolysate obtained from food waste could be a potential prebiotic and could be used in the production of a functional beverage with improved GABA content.

Bioprocess Design and Evaluation of Hydrothermal Hydrolysates from Sargassum sp. for Enhancing Arthrospira platensis Growth and Protein Content

The proliferation of Sargassum biomass in various coastal areas has led to environmental and socio-economic problems. However, due to their unique composition, these biomasses offer versatile applications, prompting research into their potential in third-generation biorefineries. In this study, the hydrothermal processing of Sargassum sp. was evaluated under specific conditions at 190 °C/50 min and 150 °C/30 min. The resulting hydrolysates (liquid phase) were used as alternative culture media for cultivation. Nine treatments for the cultivation of Arthrospira platensis were assessed, varying the concentration of hydrothermal hydrolysates (HH) at 190 °C/50 min: T1 (5% v/v), T2 (10% v/v), and T3 (15% v/v). T4 (5% v/v), T5 (10% v/v), and T6 (15% v/v), maintaining the same HH conditions, and with the addition of 0.7 g/L NaNO3; and treatments T7, T8, and T9 had concentrations of 5%, 10%, and 15% of HH, respectively, at 150 °C/30 min with the addition of 0.7 g/L NaNO3, respectively. Each treatment was inoculated with 15% (v/v) of A. platensis. Growth kinetics were performed by sampling every three days for 24 days. Quantification of soluble proteins was performed for the best conditions of biomass production. The microalgae demonstrated the ability to grow under mixotrophic medium conditions and to utilize the available carbon sources in the culture medium. Treatment 4 has the highest biomass, with an Xmax (g/L) of 1.94 ± 0.06 and a protein production of 24.17 ± 0.86% (w/w). Therefore, this microalgal biomass can be used in the food matrix according to the biorefinery concept.

Tissue Culture Studies on Shankhpushpi

Callus from root portion of seedlings of Convolvulus pluricaulis has been cultured on a medium (BM) based on Murashige and Skoog's (1962) medium. Sucrose, 1.5%; casein hydrolysate, 1250 mg/l ; IAA, 15 mg/l ; kinetin 1.5 mg/l and GA, 0.5 mg/l, individually were found optimum for the maximum growth of callus.Maximum hypotensive activity was noticed in the extract of callus tissue cultured on BM supplemented with a higher concentration of casein hydrolysate.

Bioactive, textural and sensory attributes of soft confections enriched with plant protein hydrolysates

AbstractSoft confections can serve as a reservoir for bioactive peptide delivery in both functional food and food supplement applications. In this study, pectin-based soft confections were fortified with proteolytic plant protein hydrolysates and the residual bioactivity of hydrolysates was studied after processing or simulated digestion. Cold press sunflower or hazelnut cakes were used in the manufacture of protein isolates based on an alkali extraction-isoelectric precipitation (AE-IP) method. Trypsin or bromelain were utilized in the proteolysis of the isolates and thus prepared liquid hydrolysates were used in confectionery manufacture. DPP-IV (dipeptidyl peptidase-IV) inhibitory activity (i.e., in vitro antidiabetic activity) and antioxidative activities were measured. In addition, sensory and textural attributes were investigated. In all cases, a significant concentration of hydrolysates were added to the confections (27%), which lead to significant changes in color, texture and sensory acceptance. The peptide profile and size distribution mostly altered such characteristics, while observed bioactivity was significant after processing. Simulated digestion enhanced DPP-IV inhibitory activity up to approx. 40%, whereas antioxidative performance decreased. While the applicability of the current findings is limited by hydrolysate solubility, ingredient interactions, and processing costs, the relevance of degree of hydrolysis (DH%), peptide characteristics and phenolic-peptide interactions on product quality and eventual bioactivity are being discussed.

A comprehensive investigation of the use of freeze concentration appro aches for the concentration of fish protein hydrolysates

Fish protein hydrolysates (FPH) are inherently unstable in their liquid form, necessitating either freezing or dewatering for stabilization. Gentle methods such as freeze concentration can be used to remove water, this can be achieved by freezing water in solution by decreasing the bulk temperature below freezing point and separating pure ice crystals from concentrated solution. This approach serves as an alternative to techniques like evaporation and reverse osmosis for concentrating solutions that have high water content, significant nutritional value, and thermolabile compounds. This is crucial as many bioactive compounds degrade when exposed to elevated temperatures. Another notable advantage of this technology is its potential to reduce energy consumption by up to 40% when integrated into the FPH drying process. Although this technology is currently industrialized primarily for juices, it can achieve concentrations of up to 60°Brix and manage viscosities up to 400 mPa.s. Numerous studies have been dedicated to enhancing design and processes, leading to a 35% reduction in the system's capital cost and a 20% reduction in energy consumption. Moreover, freeze concentration can synergize with other concentration techniques, creating more efficient hybrid processes. This review aims to introduce freeze concentration as a superior option for preserving fish protein hydrolysates, enhancing their stability, and maintaining their nutritional and bioactive qualities.

Enzymatic Hydrolysis of Protein Hydrolysate from Pangasius sp. by-Product using Bromelain

Fish protein hydrolysate (FPH) is a product resulting from the degradation of fish protein into simple peptides and amino acids through hydrolysis. This study aims to optimise the enzymatic hydrolysis conditions of Pangasius sp. by-products to produce high-quality fish protein hydrolysate. Bromelain enzyme was used as the catalyst for hydrolysis. The degree of hydrolysis (DH), pH and antioxidant activity of FPH were used as response parameters. The optimisation was done using response surface methodology (RSM) by applying two factors (enzyme concentration and incubation time) with a 3-level Central Composite Design (CCD) model. The result showed that the bromelain concentration and incubation time of catfish protein hydrolysate gave significantly different effects (p&lt;0.05) on the response parameters of Pangasius protein hydrolysate. Hydrolysis of Pangasius protein with 0.04% bromelain enzyme and incubation time of 2.8 hours resulted in DH, pH and DPPH antioxidant activity of 35.88%, 7.07 and 29.86%, respectively. The response value of Pangasius protein hydrolysate was within the range of the predicted value of hydrolysate. Therefore, the optimum conditions suggested by RSM can be used in the future production of Pangasius FPH. In addition, amino acid profiles of Pangasius protein hydrolysate showed high concentrations of Glycine, L-glutamic acid and L-aspartic Acid.

Harnessing tobacco stem biomass for eco-friendly xylo-oligomers production via hydrothermal treatment and succinic acid via fermentation

The integration of processes offers promising avenues for valorization of the tobacco waste, enabling the production of commercially significant compounds beyond traditional tobacco leaves designation. This research delves into the feasibility of extracting xylo-oligosaccharides (XOS) from tobacco stems via hydrothermal pretreatment. Emphasis was laid on XOS release kinetics from high solid loads (20% w/v) during pretreatment. The optimal conditions, which facilitated maximum oligomer recovery with minimal degradation compounds and reducing sugar solubilization, were then scaled up. The resultant solid fraction underwent enzymatic hydrolysis at varied solid loads (5%, 10%, and 15% w/v). Subsequent to this, succinic acid production was targeted, propelling the optimal enzymatic hydrolysate towards fermentation using the bacterium Actinobacillus succinogenes. Key findings revealed that a temperature of 190 °C during 8-min emerged as the most effective pretreatment conditions, yielding XOS at 49.54% with a concentration of 11.11 g.L−1. Enzymatic hydrolysis remained relatively uninfluenced by variations in solid loads, thereby permitting the use of high solid loads (15% w/v) to obtain concentrated hydrolysates at 49.37 g.L−1 with a conversion yield of 62.90%. Markedly, this study pioneered the demonstration of tobacco waste as a viable precursor for biosuccinic acid synthesis. Succinic acid concentration stood at 16.88 g.L−1, achieving a yield of 42%. A comprehensive mass balance evaluation spotlighted the potential to derive 56 kg of XOS and 78 kg of succinic acid per 1000 kg of tobacco raw biomass by the process developed herein.