Buckwheat Protein Research Articles

Production of Bioactive Peptides from Tartary Buckwheat by Solid-State Fermentation with Lactiplantibacillus plantarum ATCC 14917.

Buckwheat is a valuable crop that contains various nutrients and functional components. Tartary buckwheat peptide is a protease-hydrolyzed protein with a wide range of physiological functions. Tartary buckwheat peptide produced through microbial fermentation can decrease the enzymatic digestion of buckwheat protein, which contributes to the bitter taste, and improve both the flavor and texture of buckwheat peptide products. In this study, microbial fermentation using probiotics was employed to prepare Tartary buckwheat peptides, and the preparation process was optimized. Based on single-factor experiments, the polypeptide content in the fermentation solution initially increased and then decreased with varying water content, inoculum concentration, glucose addition, fermentation temperature, fermentation time, and potassium dihydrogen phosphate addition. According to the response surface methodology, the maximum peptide content was achieved under fermentation conditions of 60.0% moisture content, 12.87% inoculum ratio, 2.0% glucose, and a fermentation temperature of 30.0 °C, with an actual value of (22.18 ± 1.02) mg/mL. The results show that fermentation with Lactiplantibacillus plantarum produces higher peptide levels and is safer than other microbial fermentation methods.

Buckwheat protein as macromolecular emulsifier to stabilize antarctic krill oil-loaded emulsion: Study on physicochemical properties, microstructure, and functional properties

Buckwheat protein (BP) was studied in relation to oil phase volume fractions for the preparation of Antarctic krill oil (AKO) emulsions. The physicochemical properties and microstructure of BP-AKO emulsions were examined using zeta potential, droplet size, rheology, and laser confocal microscopy. The bioavailability of astaxanthin in AKO was assessed through in vitro digestion experiments. Among the emulsions tested, the BP-AKO (5–60%) emulsion, containing 5% protein and 60% oil phase, displayed the smallest particle size (1.86 μm), highest absolute zeta potential value (47.88 mV), and greatest interfacial protein adsorption rate (89.00%), indicating superior stability. Oxidative stability experiments revealed that the BP-AKO (5–60%) emulsion exhibited the lowest production of lipid hydroperoxides and malondialdehyde, reflecting excellent oxidative stability. Furthermore, the highest release of free fatty acids from the BP-AKO (5–60%) emulsion occurred during in vitro digestion, peaking at 70.17% after 120 min. The bioavailability of astaxanthin also reached a maximum value of 50.37%. This study provides experimental support for the use of macromolecular cereal proteins as emulsifiers to stabilize Antarctic krill oil.

Effects of glycation treatment on the structural, physicochemical, and in vitro digestible properties of tartary buckwheat protein

Tartary buckwheat protein (TBP) has a balanced amino acid composition and multiple health benefits, but it has not been fully utilized in the food industry because of its insufficient functional characteristics. Glycation is an effective strategy to enhance the function of food-derived proteins. This study was to investigate the effects of glucose and its ratio on the structure, physicochemical properties and in vitro digestibility of TBP during moist heat glycation. The results showed that glycation degree increased with glucose proportions, which facilitated the formation of TBP-glucose conjugates through hydrogen bonding, thus reducing tryptophan exposure. Moreover, glycation led to reduced aggregation between proteins and formation of more amorphous structures due to steric hindrance introduced by glucose. Notably, glycation significantly improved solubility (from 67.20% to 80.01%), foaming capacity (from 20.00% to 26.64%), and emulsifying activity (from 3.49 m2/g to 4.12 m2/g). Conversely, glycation reduced free sulfhydryl groups, surface hydrophobicity, turbidity, as well as gastric and intestinal digestibility of proteins. Considering the functional and digestive properties, the best results were obtained with TBP:glucose = 5:3. This study will help to elucidate the mechanism of TBP modification under glycation conditions and provide a theoretical basis for the development of TBP-related products.

Investigation of the structure-forming role of dietary fibre components in gluten-free cereal- and pseudocereal-based food matrices

The aim of this work was to investigate the structure-forming ability of cereal β-glucan (BG) and arabinoxylan (AX) in gluten-free (GF) dough and slurry matrices. 2, 5 or 8%, w/w BG was dosed to white millet and buckwheat flours and its effect on the mixing and pasting properties was examined. Furthermore, AX “incorporation” into dough structure and possible interaction with millet and buckwheat proteins were investigated by using reduction and subsequent re-oxidation based on our previous work.BG addition increased consistency and changed mixing properties in both millet and buckwheat doughs by forming viscous gel and aggregates. However, its impact on the pasting properties of the two types of GF flours differed in tendency. Similarly, a different behaviour of millet and buckwheat matrices was found in case of AX incorporation, explained by their distinct macromolecular (especially protein) composition. SDS-PAGE results referred to interactions between AX molecules and non-gluten proteins, however the changes in free ferulic acid contents did not confirm this. Although, white flours of millet and buckwheat are simpler matrices than wholemeals, they might be still too complex to examine the effect of a specific component, especially in a redox system. Thus, development of model gluten-free dough systems is a further goal of this work.Research works focusing on AX or BG functionality in gluten-free matrices are rare. The current work might contribute to a better understanding of dietary fibre functionality in dough systems with non-gluten proteins, as well as to develop healthier gluten-free products of higher fibre content.

Growth performance, lipid metabolism, and systemic immunity of weaned piglets were altered by buckwheat protein through the modulation of gut microbiota.

Tartary buckwheat protein (BWP) is well known for the wide-spectrum antibacterial activity and the lipid metabolism- regulating property; therefore, BWP can be applied as feed additives to improve the animal's nutritional supply. With the aim to investigate the bioactive actions of the BWP, growth performance, lipid metabolism and systemic immunity of the weaned piglets were measured, and the alterations of pig gut microbiota were also analyzed. According to the results, the growth performances of the weaned piglets which were calculated as the average daily gain (ADG) and the average daily feed intake (ADFI) were significantly increased when compared to the control group. Simultaneously, the serum levels of the total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) were decreased, while the levels of high-density lipoprotein cholesterol (HDL-C) were increased in the BWP group. Moreover, the relative abundances of Lactobacillus, Prevotella_9, Subdoligranulum, Blautia, and other potential probiotics in the gut microbiota of weaned piglets were obviously increased in the BWP group. However, the relative abundances of Escherichia-Shigella, Campylobacter, Rikenellaceae_RC9_gut_group and other opportunistic pathogens were obviously decreased in the BWP group. In all, BWP was proved to be able to significantly improve the growth performance, lipid metabolism, and systemic immunity of the weaned piglets, and the specific mechanism might relate to the alterations of the gut microbiota. Therefore, BWP could be explored as a prospective antibiotic alternative for pig feed additives.

Effect of high moisture extrusion on the structure and physicochemical properties of Tartary buckwheat protein and its in vitro digestion

Tartary buckwheat is rich in nutrients and its protein supports numerous biological functions. However, the digestibility of Tartary buckwheat protein (TBP) poses a significant limitation owing to its inherent structure. This study aimed to assess the impact of high moisture extrusion (HME, 60 % moisture content) on the structural and physicochemical attributes, as well as the in vitro digestibility of TBP. Our results indicated that TBP exhibited unfolded and amorphous microstructures after HME. The protein molecular weight of TBP decreased after HME, and a greater degradation was observed at 70 °C than 100 °C. In particular, HME at 70 °C caused an almost complete disappearance of bands near 35 kDa compared with HME at 100 °C. In addition, compared with native TBP (NTBP, 44.53 µmol/g protein), TBP subjected to HME at 70 °C showed a lower disulfide bond (SS) content (42.67 µmol/g protein), whereas TBP subjected to HME at 100 °C demonstrated a higher SS content (45.70 µmol/g protein). These changes endowed TBP with good solubility (from 55.96 % to 83.31 % at pH 7), foaming ability (20.00 %–28.57 %), and surface hydrophobicity (8.34–23.07). Furthermore, the emulsifying activity (EA) and in vitro digestibility are closely related to SS content. Notably, extruded TBP (ETBP) obtained at 70 °C exhibited higher EA and digestibility than NTBP, whereas ETBP obtained at 100 °C showed the opposite trend. Consequently, HME (especially at 70 °C) demonstrated significant potential as a processing technique for improving the functional and digestive properties of TBP.

Vertically aligned MXene bioelectrode prepared by freeze-drying assisted electrophoretic deposition for sensitive electrochemical protein detection

Two-dimensional (2D) carbides, MXenes, have attracted attention as electrode materials of electrochemical biosensors because of their metallic conductivity, hydrophilicity, and mechanical stability. However, when fabricating electrodes, the nanosheets tend to re-stack and generally align horizontally with respect to the current collector due to the highly anisotropic nature of MXene, resulting in low porosity and poor utilization of the MXene surface. Here we report the electrochemical biosensing of antibody-antigen reactions with a vertically aligned Ti3C2Tx MXene (VA-MXene) electrode prepared by freeze-drying assisted electrophoretic deposition. The macroporous VA-MXene electrode exhibited a better electrochemical response towards the immunoreaction between the allergenic buckwheat protein (BWp16) and the antibody compared to a non-porous, horizontally (in-plane) stacked MXene (HS-MXene) and the sensors reported in the literature. The sensor responsiveness, defined as the ratio of the obtained current density of the electrode to the antigen concentration, was much higher for the VA-MXene electrode (238 μA cm−2 (ng mL−1) −1) than for the HS-MXene electrode. The proposed technique is applicable to other exfoliated nanosheets, and will open a new avenue for porous nanosheet electrodes to improve the sensing characteristics of electrochemical biosensors.

The extraction of buckwheat protein and its interaction with kappa-carrageenan: Textural, rheological, microstructural, and chemical properties

Current plant-based foods use plant proteins as a key structuring and texturing ingredient. The use of water for extraction can replace conventional protein extraction methods. Water extraction of protein is environmentally friendly and could prevent the loss of protein functionality due to extreme pH changes. This study demonstrates an aqueous extraction method, coupled with ultrasound as pre-treatment, to obtain buckwheat protein (BWPE) and assess its gelling property and composited gel with kappa-carrageenan (k-carr). Textural and rheological analyses showed that the hardness and storage modulus of the composited gel containing 1 % w/w BWPE and 1 % w/w k-carr was 4.2-fold and 100-fold, respectively, higher than k-carr gel at 1 % w/w. Light microscopy showed a mixed bi-continuous gel system, with k-carr reinforcing the protein gel network. Besides volume exclusion effects, chemical bond and FTIR analyses revealed that adding k-carr to BWPE altered the protein's secondary structure and mediated protein denaturation during heating. This results in greater β-sheet content, which creates a more organised gel structure. These results demonstrated that ultrasound-assisted water-extracted BWPE, together with varying concentrations of k-carr, can be used to develop composited gels of tailorable textural and rheological properties to suit different food applications.

Comparative study of dietary phenols with Tartary buckwheat protein (2S/13S): impact on structure, binding sites and functionality of protein.

This research was to investigate the interaction mechanism between 2S albumin and 13S globulin (2S and 13S, the most important storage proteins in Tartary buckwheat seeds) and three phenols (rutin, quercetin and myricetin) regarding the structural and antioxidant properties of their complexes. There are differences in the binding affinity of phenols for 2S and 13S. Rutin had a higher binding affinity for 2S, myricetin had a higher binding affinity for 13S, and 13S exhibited a higher affinity toward phenols than did 2S. Binding with phenols significantly changed the secondary and tertiary structures of 2S and 13S, decreased the surface hydrophobic value and enhanced the antioxidant capacity. Molecular docking and isothermal titration calorimetry showed that the binding processes were spontaneous and that there were hydrogen bonds, hydrophobic bonds and van der Waals force interactions between phenols and proteins. These findings could provide meaningful guidance for the further application of buckwheat protein complex. © 2023 Society of Chemical Industry.

Study on the reduction of Tartary buckwheat allergenicity during Pediococcus pentosaceus fermentation by HPLC-MS/MS analysis.

Tartary buckwheat contains more valuable nutrients than common buckwheat, but it also contains allergenic proteins that induce allergic reactions through an IgE-mediated response. Our study demonstrated that fermentation by Pediococcus pentosaceus degrades allergenic proteins in Tartary buckwheat, as confirmed by HPLC-MS/MS analysis of polypeptides. Our results showed significant degradation of the protein after 16h of Pediococcus pentosaceus fermentation (PP16), leading to a reduction in IgE-binding activity. Comparison with unfermented Tartary buckwheat (UTB) peptides yielded 2042 fragments, of which 756 fragments associated with allergenic proteins were upregulated. Among them, the expression of 213 fragments was reduced by 71.83%. By performing bioactivity prediction on potential allergenic peptide fragments, we identified six peptide fragments derived from Fagt 1, potentially contributing to the residual allergenicity in PP16. These suggest that Pediococcus pentosaceus fermentation can effectively destroy allergen epitopes and mitigate the allergenicity of Tartary buckwheat.

Nitrogen regulates the synthesis of hydrophobic amino acids to improve protein structural and gel properties in common buckwheat

Nitrogen (N) fertilizer impacts the grain quality of common buckwheat, but the effects and regulatory mechanisms of N on various protein parameters of buckwheat are not fully understood. The purpose of this study was to investigate the particle morphology, structural and gel properties, and regulation mechanism of buckwheat protein under four N levels. The bulk density, surface hydrophobicity, particle size, and thermal properties of the buckwheat protein were maximized through the optimal N application (180 kg N/ha), further enhancing the thermal stability of the protein. N application increased the β-sheet content and reduced the random coil content. Appropriate N fertilizer input enhanced the tertiary structure stability and gel elasticity of buckwheat protein by promoting hydrophobic interactions, disulfide bonds, ionic bonds, storage modulus and loss modulus. The differentially expressed proteins induced by N are primarily enriched in small ribosomal subunit and ribosome, improving protein quality mainly by promoting the synthesis of hydrophobic amino acids. Future agriculture should pay attention to the hydrophobic amino acid content of buckwheat to effectively improve protein quality. This study further advances the application of buckwheat protein in the field of food processing and provides a theoretical basis for the extensive development and utilization of buckwheat protein.

The interaction mechanisms, biological activities and digestive properties between Tartary buckwheat protein and phenolic extract under pH-driven methods.

The preparation of Tartary buckwheat protein and phenolic extract complex by pH-driven treatment was studied. The phenols identified by HPLC-MS spectrometry mainly include rutin, quercetin and kaempferol. The content of phenol bound to protein was 33.49 and 6.31mg/g. The FT-IR and fluorescence spectroscopy confirmed that the treatment of pH-driven and combination of phenol can affect the secondary and tertiary structure of the protein. The alteration of free sulfhydryl content indicated that there may be binding between phenol and Cys residue of protein. Molecular docking analysis showed the binding sites of the phenols and protein treated at different pH values were significantly different. Furthermore, In the simulated digestion in vitro, the digestibility of complex was significantly lower than that of protein. Pepsin can promote the antioxidant ability, and have little effect on ADH activation. The above result can play a positive role in the development of the food field.

Metabolic-GWAS provides insights into genetic architecture of seed metabolome in buckwheat

BackgroundBuckwheat (Fagopyrum spp.), belonging to the Polygonaceae family, is an ancient pseudo-cereal with high nutritional and nutraceutical properties. Buckwheat proteins are gluten-free and show balanced amino acid and micronutrient profiles, with higher content of health-promoting bioactive flavonoids that make it a golden crop of the future. Plant metabolome is increasingly gaining importance as a crucial component to understand the connection between plant physiology and environment and as a potential link between the genome and phenome. However, the genetic architecture governing the metabolome and thus, the phenome is not well understood. Here, we aim to obtain a deeper insight into the genetic architecture of seed metabolome in buckwheat by integrating high throughput metabolomics and genotyping-by-sequencing applying an array of bioinformatics tools for data analysis.ResultsHigh throughput metabolomic analysis identified 24 metabolites in seed endosperm of 130 diverse buckwheat genotypes. The genotyping-by-sequencing (GBS) of these genotypes revealed 3,728,028 SNPs. The Genome Association and Prediction Integrated Tool (GAPIT) assisted in the identification of 27 SNPs/QTLs linked to 18 metabolites. Candidate genes were identified near 100 Kb of QTLs, providing insights into several metabolic and biosynthetic pathways.ConclusionsWe established the metabolome inventory of 130 germplasm lines of buckwheat, identified QTLs through marker trait association and positions of potential candidate genes. This will pave the way for future dissection of complex economic traits in buckwheat.

Effect of pH treatment on physical stability and antioxidant activity of buckwheat protein/soybean polysaccharide nanocomplex embedded pterostilbene

This study prepared buckwheat protein (BP)/soybean soluble polysaccharides (SSPS) nanoparticles for PTS encapsulation, exhibiting nanocomplexes with sizes of under 300 nm, spherical particles and strong negative charge (−20 ∼ −40 mV). Moreover, the addition of SSPS enhanced the embedding effect of PTS from 61.38% to 89.78%. X-ray and fluorescence spectroscopy revealed that PTS can bind to BP and SSPS. Molecular docking analysis showed PTS can bind to BP with hydrogen bonds and hydrophobic bonds at pH 7.0, only can bind with hydrophobic bonds at pH 4.5. Stability experiments revealed that nanocomplex had higher physical and foam stability. Antioxidant experiments revealed that antioxidant capacity of PTS in the nanocomplex was significantly higher than that in the free state. Therefore, the research findings can be advantageous to the utilization of PTS in functional foods.

APPLICATION OF TWO-DIMENSIONAL ELECTROPHORESIS AND MASS SPECTROMETRY FOR THE DETECTION OF ALLERGENS IN SELECTED VARIETIES OF WHEAT, OATS AND BUCKWHEAT

The number of people suffering from food allergies and intolerances has been increasing in recent years and cereal proteins are the most common food allergens. Pseudocereals represent perspective alternative in nutrition with a positive effect on the human body. The aim of the work was to analyze the proteome of selected varieties of wheat (Triticum aestivum L.), oats (Avena sativa) and buckwheat (Fagopyrum esculentum Moench.) using two-dimensional electrophoresis (2DE) and mass spectrometry in order to detect the presence of potentially allergenic proteins. Using the PDQuest program, 221 protein spots ranging from 4.13 to 9.89 µl with experimental molecular weights from 12.42 kDa to 140 kDa were quantified in 2DE gels of wheat. In the oat sample, 168 protein spots were quantified in the range pI of 4.02 to 9.93 and an experimental molecular weight of 14.81 kDa to 67.96 kDa. Buckwheat proteins were separated on a 2DE gel into 208 protein spots in the 3 to 9.83 pI region with an experimental molecular weight of 10.10 kDa to 115 kDa. By comparing the data with the Allergome database, allergens Tri and 26, Tri and 33, Tri and 36, Tri and alpha Gliadin, Tri and 20 were detected in wheat, Ave s 11S allergens in oats and Fag e 1 allergen in buckwheat. 2DE together with mass spectrometry have been shown to be suitable and sensitive methods for the detection of allergens in food crops.

Effects of enzyme deactivation conditions on the structure, bound phenol content and antioxidant property of phenol modified Tartary buckwheat protein hydrolysate

In this study, the effects of different enzyme deactivation methods (80, 100, 4 °C and pH 6.0) on the structural characteristics, bound polyphenol content and antioxidant activity of buckwheat protein hydrolyzate-phenol complex (BHP) were investigated. Alcalase was selected for enzymolysis. Amino acid analysis showed that glutamic acid was the most important amino acid in hydrolysate. Molecular weight distribution analysis showed that the hydrolysis can be completed at 3 h. After enzyme deactivation treatment, all hydrolysates were dialyzed to remove aggregates/enzymes (15 kDa). Fourier transform infrared spectroscopy (FTIR) analysis revealed that the characteristic peaks of BHP shifted after treatment. The fluorescence spectra and surface hydrophobicity (Ho) showed that the corresponding values of BHP increased significantly when deactivated at 80 °C and pH 6.0, decreased at 100 °C and remained no change at 4 °C. The content of total bound polyphenol increased when treated at 80 and 4 °C, and decreased at 100 °C and pH 6.0. Meanwhile, the results showed that all BHP have high antioxidant capacity. This work can provide more support for the systematic evaluation of enzyme deactivation methods containing phenolic hydrolysates.

Characterization, Formation Mechanism, and Curcumin Delivery of Buckwheat Peptide-Based Emulsion Gels.

This study aimed to construct a natural peptide-based emulsion gel (PG) using small peptides (∼2.2 kDa) by mild enzymatic hydrolysis of buckwheat proteins. The obtained PG presented a porous and tight texture and solid-gel viscoelasticity compared with its parent protein-based emulsion gel. Meanwhile, it exhibited good resistance against heating and freeze-thawing. Furthermore, peptide-oil interaction analysis revealed that the gel matrix was enhanced by the hydrophobic aggregation between peptides and oil molecules, H-bonding interaction of peptide molecules, and peptide-oil aggregate repulsion force. Finally, in vitro intestinal digestion experiments demonstrated that PG could embed and pH-responsively release curcumin in the gastrointestinal tract at a release rate of 53.9%. The findings unfold promising opportunities for using natural PG in a range of applications relying on large proteins or other synthesized molecules.

Spray-drying microencapsulation of blackcurrant and cocoa polyphenols using underexplored plant-based protein sources.

The performance of buckwheat protein (BK) and chia seed protein (CP) as drying carriers for the microencapsulation of polyphenols extracted from blackcurrant pomace and cocoa powder was investigated. Four experimental groups were evaluated (BK-BC: blackcurrant pomace extract with buckwheat protein; CP-BC: blackcurrant pomace extract with chia:pea protein blend; BK-CC: cocoa extract with buckwheat protein; and CP-CC: cocoa extract with chia:pea protein blend) to determine physicochemical attributes, phytochemical content, antioxidant activity, and polyphenol in vitro bioaccessibility. Nonconventional, underexploited protein sources such as chia/pea protein blend and buckwheat protein efficiently produced functional microparticles with attractive color and texture, low hygroscopicity (<20% increase in moisture content when exposed to 86% relative humidity for 1week), solubility above 50% at pH 7 and 10, and uniform particle size (29<D4,3 <56µm). Besides this, the protein-polyphenol microparticles concentrated and protected health-relevant polyphenol content. Anthocyanins were detected in blackcurrant treatments (around 20mg cyanidin-3-O-glucoside equivalents/g), while proanthocyanidins (PAC) were the most prevalent polyphenols in cocoa treatments (>100mg PAC B2/g). Monomers were the main class of PAC in both BK-CC and CP-CC treatments. All protein-polyphenol treatments reduced both reactive oxygen species and nitric oxide production in lipopolysaccharide-activated cells (p<0.05). The polyphenol recovery index was high (>70%) for both oral and gastric phases, and BK-derived groups had better bioaccessibility index compared to BC or CC alone (noncomplexed). This research provided a framework for delivery of high-value ingredients to attend to an emerging market centered on protein-rich, clean label plant-based food products. PRACTICAL APPLICATION: Practical Application: The protein-polyphenol complexation is a robust method to produce phytochemical-rich food ingredients for the food industry with enhanced physicochemical, sensory, and bioaccessibility performance. In this study, we investigated practical aspects regarding the production and quality of protein-polyphenol particles, such as the spray-drying efficiency, phytochemical content, physicochemical attributes, antioxidant activity, and polyphenol bioaccessibility. This study unveils the potential of underexplored buckwheat and chia seeds (alone or combined with pea protein) as encapsulation carriers for fruit polyphenols to diversify the protein options available for products directed to the wellness market.

Isolation and identification of angiotensin-converting enzyme inhibitory peptides from Tartary buckwheat albumin.

Tartary buckwheat protein peptides have been shown to be able to inhibit angiotensin-converting enzyme (ACE), but the exact protein type has been less studied for ACE activity inhibition, and only a few types of ACE inhibitory peptides have been reported. In this study, we purified and identified ACE inhibitory peptides from albumin hydrolysate (AH). Albumin, globulin, prolamin and glutelin were extracted from Tartary buckwheat, and their ACE active peptides were obtained by a pepsin-trypsin sequential hydrolysis process. All four hydrolysates exhibited ACE inhibitory activity, and AH displayed the strongest ACE inhibition activity and the highest peptide yield (82.28%). At 0.2 mg mL-1 , the inhibition rate of AH was 79.89%, followed by globulin hydrolysate at 71.84%, while prolamin hydrolysate and glutelin hydrolysate showed lower inhibition rates. The peptides with the highest inhibition rate were then isolated from AH using gel filtration chromatography and reversed-phase high-performance liquid chromatography, and identified using nanoscale high-performance liquid chromatography-tandem mass spectrometry. After isolation and purification, 42 ACE inhibitory peptides were identified in the fraction with the highest inhibition rate, 14 of which were completely novel discoveries in this study. These 14 peptides showed potent ACE inhibitory effects through computer analysis. Tartary buckwheat albumin can be used as a good source of ACE inhibitory peptides and can be further developed and utilized as edible supplements or drugs. © 2023 Society of Chemical Industry.

Fabrication of buckwheat-shellac complex by pH-driven enhances the viability of Lactiplantibacillus plantarum during simulated gastrointestinal and storage conditions

The acid sensitivity and moisture absorption of dry probiotic products during digestion and storage are challenges. In this study, different mass ratios (1, 1.5, 2, 2.5, 5) of buckwheat protein (BWP) and hydrophobic polyester shellac were firstly combined by a pH-shifting method and then applied for the construction of Lactobacillus plantarum (L. plantarum) microcapsules. Circular dichroism (CD) and fluorescence spectroscopy results revealed that the complexes were stabilized primarily by hydrophobic interaction forces and the conformational changes after co-folding with shellac. With a decreasing ratio of shellac, the enthalpy (ΔH) and peak temperature increased, resulting in enhanced thermal stability. BS2 encapsulated probiotics successfully enhances the survival of L. plantarum during freeze-drying and gastrointestinal (GI) digestion. The probiotic was fully coated by the complex, determined through scanning electron microscopy (SEM) images. After encapsulated, the colon adhesion efficiency enhanced 30.92% than free cells. The encapsulated probiotics presented a maximum reduction of 0.89 log CFU/mL after 30 days of storage at 25 °C, and probiotics protected by the BS1 complex had superior storage stability under an Aw of 0.76, for which K value was 1.218. BWP-based shellac pH-shift complexes exhibit enormous potential for the encapsulation of probiotics.