Soybean Peptide Research Articles

Soy Peptide Ameliorate TGF-β1-Mediated Osteoblast Differentiation through Smad and MAPK Signaling Pathways.

The aim of this study was to determine the osteogenic activity and mechanism of soybean peptide VVELLKAFEEKF (SOP) and the potential relationship between SOP and transforming growth factor-β1 (TGF-β1). The results show that SOP promotes MC3T3-E1 cell proliferation by altering cell progression. SOP induced cell differentiation and mineralization in a dose-dependent manner at 0.7-7 μM. Moreover, SOP stimulates osteoblast differentiation, which may be achieved through the activation of p38-MAPK and Smad2/3 signaling pathways. Furthermore, treatment with a TβRI inhibitor (SB525334) inhibited the phosphorylation levels of p38 and Smad2/3, which indicates the involvement of TβRI in the process of osteoblast differentiation caused by SOP. Besides, in non-FBS-cultured MC3T3-E1 cells, SOP and TGF-β1 promoted the phosphorylation of Smad2/3 and alkaline phosphatase (ALP) activity, but the effect was lost when SOP was incubated separately, indicating that SOP stimulated osteoblast differentiation by promoting TGF-β1 activity. In vivo, SOP significantly restores bone mineral density loss and behavioral deficits in a model of glucocorticoid-induced osteoporosis (GIOP) in zebrafish. These results suggest that SOP may have the function of promoting bone remodeling and may be used as a potential active factor for functional food development to prevent osteoporosis.

Chitosan encapsulation soy peptide–calcium promotes calcium absorption and bone health of rats fed a low calcium diet

Calcium deficiency is considered widespread globally, and discovering calcium with high bioavailability is one of the keys to solving calcium deficiency. This study prepared a calcium delivery system with chitosan and soy peptide and investigated its characteristics, ability to promote calcium absorption, and effects on bone health. The experiment results reveal that chitosan encapsulates soybean peptide–calcium (COS–SPs–Ca) with carboxyl oxygen atoms, amino nitrogen atoms, and phosphate ions, which has a slow-release effect in simulated gastrointestinal digestion. In calcium-deficient rats, COS–SPs–Ca has beneficial effects on serum biochemical parameters, bone biomechanics, and bone microarchitecture, and significantly up-regulated the gene expression of TRPV5, TRPV6, PepT1, and Calbindin-D9k in the small intestine. These results suggest that COS–SPs–Ca is a promising calcium supplement.

Antihypertensive and antioxidant effects of food-derived bioactive peptides in spontaneously hypertensive rats.

Hypertension significantly impacts the survival and quality of life of animals, often leading to chronic kidney failure. Current clinical drugs used to manage hypertension carry the risk of causing adverse reactions. In contrast, certain natural peptides have demonstrated the ability to safely reduce blood pressure by inhibiting the production of angiotensin. We administered four biologically active peptide solutions to spontaneously hypertensive rats: derived from corn, wheat, egg white, and soybean. The efficacy of these peptides in reducing blood pressure was assessed through regular measurements of systolic pressure. Additionally, we analyzed levels of angiotensin-converting enzyme and angiotensin 2 using immunohistochemistry and ELISA invivo. The indicators of oxidative stress and inflammation in hypertensive rats were evaluated using qRT-PCR and ELISA, respectively. Both wheat (from 182.5 ± 12.26 mmHg at day 0 to 168.86 ± 5.86 mmHg at day 20, p = .0435) and soybean (from 189 ± 2.19 mmHg at day 0 to 178.25 ± 5.14 mmHg at day 20, p = .0017) notably lowered systolic blood pressure compared to their starting systolic blood pressures in spontaneously hypertensive rats. Both wheat and soybean peptides significantly reduced plasma ANG II levels, akin to captopril's effect. Wheat peptides additionally exhibited antioxidant properties. Only the corn peptide showed a significant increase in transcript levels of the proinflammatory factors IL-6 and TNF-α. At the protein level, all four kinds of peptides significantly elevated IL-6 levels while inhibiting TNF-α secretion. This study demonstrates that wheat peptides and soybean peptides administered as dietary supplements exhibit significant hypotensive and antioxidant effects.

Anti-Inflammatory, Cytotoxic, and Genotoxic Effects of Soybean Oligopeptides Conjugated with Mannose.

Soy protein is considered to be a high-quality protein with a range of important biological functions. However, the applications of soy protein are limited due to its poor solubility and high level of allergenicity. Its peptides have been of interest because they exert the same biological functions as soy protein, but are easier to absorb, more stable and soluble, and have a lower allergenicity. Moreover, recent research found that an attachment of chemical moieties to peptides could improve their properties including their biodistribution, pharmacokinetic, and biological activities with lower toxicity. This study therefore aimed to acquire scientific evidence to support the further application and safe use of the soybean oligopeptide (OT) conjugated with allulose (OT-AL) or D-mannose (OT-Man). The anti-inflammation, cytotoxicity, and genotoxicity of OT, OT-AL, and OT-Man were investigated. The results showed that OT, AL, Man, OT-AL, and OT-Man at doses of up to 1000 µg/mL were not toxic to HepG2 (liver cancer cells), HEK293 (kidney cells), LX-2 (hepatic stellate cells), and pre- and mature-3T3-L1 (fibroblasts and adipocytes, respectively), while slightly delaying the proliferation of RAW 264.7 cells (macrophages) at high doses. In addition, the oligopeptides at up to 800 µg/mL were not toxic to isolated human peripheral blood mononuclear cells (PBMCs) and did not induce hemolysis in human red blood cells (RBCs). OT-Man (200 and 400 µg/mL), but not OT, AL, Man, and OT-AL, significantly reduced the production of NO and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) stimulated by lipopolysaccharide (LPS) in RAW 264.7 cells, suggesting that the mannose conjugation of soy peptide had an inhibitory effect against LPS-stimulated inflammation. In addition, the secretion of interleukin-6 (IL-6) stimulated by LPS was significantly reduced by OT-AL (200 and 400 µg/mL) and OT-Man (400 µg/mL). The tumor necrosis factor-α (TNF-α) level was significantly decreased by OT (400 µg/mL), AL (400 µg/mL), OT-AL (200 µg/mL), and OT-Man (200 and 400 µg/mL) in the LPS-stimulated cells. The conjugation of the peptides with either AL or Man is likely to be enhance the anti-inflammation ability to inhibit the secretion of cytokines. As OT-Man exhibited a high potential to inhibit LPS-induced inflammation in macrophages, its mutagenicity ability was then assessed in bacteria and Drosophila. These findings showed that OT-Man did not trigger DNA mutations and was genome-safe. This study provides possible insights into the health advantages and safe use of conjugated soybean peptides.

The screening of α-glucosidase inhibitory peptides from β-conglycinin and hypoglycemic mechanism in HepG2 cells and zebrafish larvae

Inhibition of carbohydrate digestive enzymes is a key focus across diverse fields, given the prominence of α-glucosidase inhibitors as preferred oral hypoglycaemic drugs for diabetes treatment. β-conglycinin is the most abundant functional protein in soy; however, it is unclear whether the peptides produced after its gastrointestinal digestion exhibit α-glucosidase inhibitory properties. Therefore, we examined the α-glucosidase inhibitory potential of soy peptides. Specifically, β-conglycinin was subjected to simulated gastrointestinal digestion by enzymatically cleaving it into 95 peptides with gastric, pancreatic and chymotrypsin enzymes. Eight soybean peptides were selected based on their predicted activity; absorption, distribution, metabolism, excretion and toxicity score; and molecular docking analysis. The results indicated that hydrogen bonding and electrostatic interactions play important roles in inhibiting α-glucosidase, with the tripeptide SGR exhibiting the greatest inhibitory effect (IC50 = 10.57 μg/mL). In vitro studies revealed that SGR markedly improved glucose metabolism disorders in insulin-resistant HepG2 cells without affecting cell viability. Animal experiments revealed that SGR significantly improved blood glucose and decreased maltase activity in type 2 diabetic zebrafish larvae, but it did not result in the death of zebrafish larvae. Transcriptomic analysis revealed that SGR exerts its anti-diabetic and hypoglycaemic effects by attenuating the expression of several genes, including Slc2a1, Hsp70, Cpt2, Serpinf1, Sfrp2 and Ggt1a. These results suggest that SGR is a potential food-borne bioactive peptide for managing diabetes.

Enhancing the solubility and stability of Dendrobium officinale flavonoids through interaction with soybean peptides

Enhancing the solubility and stability of Dendrobium officinale flavonoids through interaction with soybean peptides

The zinc absorption of the novel peptide-Zn complex in Caco-2 cells: effects of soybean peptides charge and hydrophobicity.

The supplemental effect of zinc depends not only on adequate intake, but also on how efficiently it is absorbed in the small intestine. In the present study, weak hydrophobic peptides (WHP), strong hydrophobic peptides (SHP), positively charged peptides (PCP) and negatively charged peptides (NCP) were isolated from soybean peptides (SP). The peptide-Zn complexes (PCP-Zn, NCP-Zn, WHP-Zn, SHP-Zn and SP-Zn) were prepared to compare their promotion zinc absorption capacity in the Caco-2 cells monolayers model. We found that the carboxyl, carbonyl and amino groups in peptide were the primary binding sites of Zn. Compared with zinc sulfate, the peptide-Zn complexes with different charge and hydrophobic peptides could improve zinc solubility at different pH. NCP-Zn had a lower Zn-binding capacity but a higher zinc absorption capacity compared to that of PCP-Zn in Caco-2 cells. In addition, the capacity of PCP-Zn to promote zinc absorption was lower than the control group (SP-Zn). There were no significant differences in transport rates, retention rates and uptake rates of WHP-Zn, SHP-Zn and SP-Zn. NCP-Zn could improve the activity of Zn-related enzymes, and the expression levels of PepT1 and ZnT1 were higher than other peptide-Zn complexes. The promotion zinc absorption capacity of peptide-Zn complexes was not completely dependent on the Zn-binding capacity, but also depended on the charge and hydrophobicity of peptides. © 2024 Society of Chemical Industry.

Novel antioxidant peptides from soybean protein by employing computational and experimental methods and their mechanisms of oxidative stress resistance

Antioxidant peptides have the potential to play a crucial role in mitigating and managing a variety range of diseases associated with oxidative stress. Soybean protein is an important source of antioxidant peptides. Here we employ computational and experimental methods to screen and identify five antioxidant peptides (Gly-Ala, Gly-Val-Pro-Tyr, Pro-His, Pro-Lys, and Ser-Gly-Pro) derived from soybean protein, and explore their potential targets and mechanisms of action. All five peptides demonstrated potent antioxidant activity, effectively scavenging superoxide radicals and protecting cells from H₂O₂-induced oxidative damage. These peptides exhibited multi-target effects on pathways implicated in oxidative stress, cardiovascular disease, and cancer. Notably, our results reveal that these peptides can stably interact with the key target nitric oxide synthase (NOS2) through Glu377, a critical residue of NOS2, thereby inhibiting its activity and potentially mitigating oxidative stress and inflammation. This study confirms the function of soybean peptide sequence that has not been previously disclosed, and provides a more specific theoretical basis for the development of natural antioxidant peptides.

Proteomic Characterization of a Lunasin-Enriched Soybean Extract Potentially Useful in the Treatment of Helicobacter pylori Infection.

Helicobacter pylori infection affects over 50% of the world's population and leads to chronic inflammation and gastric disorders, being the main pathogen correlated to gastric cancer development. Increasing antibiotic resistance levels are a major global concern and alternative treatments are needed. Soybean peptides and other compounds might be an alternative in the treatment to avoid, eradicate and/or control symptoms of H. pylori infection. This study aimed to characterize a lunasin-enriched soybean extract (LSE) using proteomics tools and to evaluate its antioxidant, anti-inflammatory and antibacterial properties against H. pylori infection. By LC-MS/MS analysis, 124 proteins were identified, with 2S albumin (lunasin and large-chain subunits) being the fourth most abundant protein (8.9%). Lunasin consists of 44 amino acid residues and an intramolecular disulfide bond. LSE at a low dose (0.0625 mg/mL) reduced ROS production in both H. pylori-infected and non-infected AGS gastric cells. This led to a significant reduction of 6.71% in the levels of pro-inflammatory interleukin (IL)-8. LSE also showed antibacterial activity against H. pylori, which can be attributed to other soybean proteins and phenolic compounds. Our findings suggest that LSE might be a promising alternative in the management of H. pylori infection and its associated symptoms.

Digestion inhibition of potato starch-botanical proteolytic polypeptides complexes subjected to heat moisture treatment based on steric hindrance and enzymatic inhibition

The effects of food components on starch digestibility is a prominent topic within the realms of food and nutritional science. In this study, complexes of potato starch (PS) and botanical proteolytic polypeptides (BPPs), including wheat peptides, maize peptides, rice peptides, and soybean peptides, were subjected to heat-moisture treatment (HMT). The physicochemical, structural, and digestibility variations of the PS-BPPs complexes were analyzed using polarized light microscopy, DSC, X-ray, FT-IR, SAXS, and in vitro simulated digestion. Additionally, we evaluated the inhibitory effects of BPPs on porcine pancreatic α-amylase (PPA). The results showed that the polarization cross of PS-BPPs complexes was weakened after HMT. The gelatinization temperatures (To, Tp, Tc) of the PS-BPPs complexes increased significantly. The starch in the PS-BPPs complexes transitioned from B-type structure to A-type structure after HMT, accompanied by an increase in short-range ordering and semicrystalline lamella thickness. In particular, the complexes exhibited higher contents of slowly digestible starch (SDS) and resistant starch (RS). Furthermore, wheat, rice, and soybean peptides exhibited a mixed type of competitive inhibition against PPA, whereas maize peptides exhibited competitive inhibition. The findings provide valuable insights into the role of BPPs in regulating starch digestion. Moreover, BPPs hold potential for enhancing the nutritional value and health benefits of foods.

Systematic sequence characterization of enzymatic-derived soybean peptides for precision enhancement of anti-inflammatory properties

Food-derived soybean peptides possess inflammation-preventive effects beyond basic nutrition due to their structural configuration. However, the relationship between sequence characteristics and their anti-inflammatory properties remains poorly understood. The lack of targeted peptide production methods limits their use in functional foods. Hydrophobic and basic amino acids enhance peptide anti-inflammatory activity. Alcalase and Papain facilitate hydrophobic and basic amino acid preparation, while Bromelain lacks specific cleavage sites. Endopeptidases selectively break peptide bonds within proteins. We subsequently used Flavourzyme, lacking specific cleavage sites, to sequentially shorten peptide chains from their terminal ends. This sequential use of endo- and exopeptidases enables efficient peptide preparation. However, the proteases' ability to selectively produce peptides with specific sequence characteristics and their contribution to the soybean peptide mixture remain unknown. This study examined three soybean peptide groups prepared using distinct methods (Alcalase + Flavourzyme: hydrophobic amino acid-rich peptides, Papain + Flavourzyme: basic amino acid-rich peptides, and Bromelain + Flavourzyme: balanced amino acid compositions) with different sequence characterizations linked to endonuclease cleavage sites. All groups inhibited nitric oxide (NO) and inducible nitric oxide synthase (iNOS) secretion, suppressing protein phosphorylation in the Phosphatidylinositol 3-kinase (PI3K)/Protein kinase B (Akt)/Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) (PI3K/Akt/NF-κB) signaling pathway. PF peptides showed the strongest anti-inflammatory effect, targeting iNOS, inhibiting TLR4, and reducing Akt and IκB phosphorylation. Mass spectrometry revealed correlations between regulatory mechanisms and the abundance of branched amino acids at PF peptides' N-terminals and significant Arg presence at their C-terminals. This study validates optimal enzymatic processes, introduces sequence characterization analysis, and identifies key features influencing anti-inflammatory properties, providing a theoretical basis for soybean peptide applications in inflammation-preventing functional foods.

Structure identification of selenium-biofortified soybean peptides and its effect on TGF-β mediated liver fibrosis pathway

Selenium-biofortified soybean peptides (SeSPs) has been verified to relieve CCl4-induced liver fibrosis in vivo previously. In the present study, the structures of SeSPs were characterized by HPLC-ESI-MS/MS and thirty-eight selenium-containing peptides sequences were identified. KLPISeM was screened out as the most promising peptide to inhibit TGF-β/Smads pathway with stable binding site to TGF-β in molecular docking. Besides, homo sapiens liver cell line (L-O2) and hepatic stellate cells from rat (HSC-T6) were treated with KLPISeM/KLPIM and TGF-β1 to explore the regression fibrosis mechanisms of peptides. Results showed that the apoptosis trend of L-O2 was inhibited while HSC-T6 apoptosis was promoted by KLPISeM. Smad2/3/4 gene levels were reduced by 60.36%, 59.08% and 71.82%, respectively and Smad7 gene expression was upregulated significantly (p < 0.05) after incubation with KLPISeM. More importantly, KLPISeM exhibited strong up-regulation effect on matrix metallo-proteinase (MMPs) and suppressive effect on tissue inhibitor of metalloproteinase gene/protein expressions in HSC-T6. These results suggested that KLPISeM could relieve liver fibrosis by blocking TGF-β/Smads and regulating MMPs/TIMPs pathway.

Investigating the antibacterial mode of Limosilactobacillus reuteri LR08 regulated by soybean proteins and peptides

Soybean proteins (pro) and soybean peptides (pep) are beneficial to the growth and metabolism of Limosilactobacillus reuteri (L. reuteri). However, whether they could assist L. reuteri in inhibiting intestinal pathogens and the inhibition mode of them is still unclear. In this study, a co-culture experiment of L. reuteri LR08 with Escherichia coli JCM 1649 (E. coli) was performed. It showed that pro and pep could still favour the growth of L. reuteri over E. coli under their competition. The inhibition zone experiment showed the digested soybean proteins (dpro) could improve its antibacterial activity by increasing the secretion of organic acids from L. reuteri. Furthermore, digested soybean peptides (dpep) could enhance nitrogen utilization capacity of L. reuteri over E. coli. These results explained the patterns of dpro and dpep assisting L. reuteri in inhibiting the growth of E. coli by regulating its organic acid secretion and the ability of nitrogen utilization.

The Potential Role of Soybean Bioactive Peptides in the Prevention and Cure of Carcinoma and Cardiovascular Disorder

Abstract: Bioactive peptides derived from soybeans have recently been identified as having potential health benefits for preventing and curing cancer and cardiovascular disorders. This narrative review focuses on the potential role of these peptides in such conditions and the possible mechanisms by which they may act. Soybean-derived bioactive peptides have been found to possess antitumor, antioxidant, anti-inflammatory, and cholesterol-lowering effects. Animal and in vitro studies have demonstrated that these peptides can modulate multiple signaling pathways, including those involved in the regulation of apoptosis, angiogenesis, and cell proliferation. Furthermore, they may protect against oxidative stress and lipid accumulation, which are associated with cancer and cardiovascular diseases. Also, soybean peptides have been shown to stop enzymes from breaking down cancer-causing chemicals and reduce the production of pro-inflammatory cytokines, which are linked to a higher risk of heart disease. The potential of soybean-derived peptides as a therapeutic tool in cancer and cardiovascular diseases is promising. However, further studies are needed to elucidate their mechanisms of action and assess their safety and efficacy in clinical settings.

Sporopollenin microencapsulation as a strategy to improve soybean peptide acceptance

Sporopollenin microencapsulation as a strategy to improve soybean peptide acceptance

Evaluating the capability of soybean peptides as calcium ion carriers: a study through sequence analysis and molecular dynamics simulations.

Calcium homeostasis imbalance in the body can lead to a variety of chronic diseases. Supplement efficiency is essential. Peptide calcium chelate, a fourth-generation calcium supplement, offers easy absorption and minimal side effects. Its effectiveness relies on peptide's calcium binding capacity. However, research on amino acid sequences in peptides with high calcium binding capacity (HCBC) is limited, affecting the efficient identification of such peptides. This study used soybean peptides (SP), separated and purified by gel chromatography, to obtain HCBC peptide (137.45 μg mg-1) and normal peptide (≤95.78 μg mg-1). Mass spectrometry identified the sequences of these peptides, and an analysis of the positional distribution of characteristic amino acids followed. Two HCBC peptides with sequences GGDLVS (271.55 μg mg-1) and YEGVIL (272.54 μg mg-1) were discovered. Molecular dynamics showed that when either aspartic acid is located near the N-terminal's middle, or glutamic acid is near the end, or in cases of continuous Asp or Glu, the binding speed, probability, and strength between the peptide and calcium ions are superior compared to those at other locations. The study's goal was to clarify how the positions of characteristic amino acids in peptides affect calcium binding, aiding in developing peptide calcium chelates as a novel calcium supplement.

In silico prediction aided preparation of antioxidant soybean peptides by enzymatic hydrolysis for ameliorating lead exposure-induced toxicity.

Food derived bioactive peptides are prominent dietary supplements to protect against oxidative stress induced by lead (Pb) exposure. This study aimed to develop a new strategy for rapid preparation of highly active antioxidant soybean polypeptides (ASPs) against Pb toxicity. In silico enzymatic hydrolysis simulation and antioxidant activity prediction showed that pepsin, chymotrypsin and bromelain can produce peptides with the highest activity. The preparation process was then optimized, and the obtained ASP showed good antioxidant and metal-chelating activities in vitro. An in vivo study showed that ASP exerted prominent protective effects against Pb-induced cognitive impairment and tissue damage in mice by reducing Pb deposition and enhancing the antioxidant capacity in tissues and was superior to Vc, DMSA or their combination in some aspects. ASP composition analysis demonstrated that its prominent antioxidant activity might be attributed to the high proportion of amino acid residues E, L, P and V in the peptide sequence and L, V and A at the C- and N-termini. In conclusion, in silico prediction could facilitate the preparation of ASP. And the ASP prepared with the new strategy exerted prominent protective effects against Pb toxicity.

Effects of Different Levels of Soybean Bioactive Peptides and Vitamin E on Performance, Egg Quality, and Serum Metabolites of Laying Hens

An experiment was carried out to find out how laying hen performance, egg quality, and serum metabolites were affected by adding soybean bioactive peptide (SBP) and vitamin E to their diet. Ninety Lohmann Extra hens that were 45 weeks old were divided into five groups at random. Each group consisted of three replicates, each with six birds. The dietary treatments included 250 mg/kg of vitamin E added to the baseline diet, 2.5, 5, and 7.5 g/kg of diet for the SBP groups, and the basal diet as the control. The findings demonstrated that egg production rate and egg weight significantly increased with SBP supplementation (P≤0.05). While there were no appreciable changes between the vitamin E-treated groups and the control group, there was a noticeable difference in feed efficiency between the SBP groups and the control group. Peptides-supplemented groups showed a definite advantage in terms of egg quality attributes, as evidenced by the weights of egg components, yolk index, and albumin index. The SBP supplement also resulted in an increase in glutathione peroxides (GSH-PX) and superoxide dismutase (SOD). Additionally, compared to the positive control treatment (adding vitamin E), there was a substantial (P≥0.05) drop in the cholesterol levels in the yolk among the groups supplemented with peptides. The group that got an excessive amount of soybean peptide (5 g/kg) had the highest serum total antioxidant activity. The findings concluded that adding SBP to the diets can enhance egg quality and production while also influencing the hens' serum's total antioxidant activity during the laying phase.

Selenium-Enriched Soybean Peptides as Novel Organic Selenium Compound Supplements: Inhibition of Occupational Air Pollution Exposure-Induced Apoptosis in Lung Epithelial Cells.

The occupational groups exposed to air pollutants, particularly PM2.5, are closely linked to the initiation and advancement of respiratory disorders. The aim of this study is to investigate the potential protective properties of selenium-enriched soybean peptides (Se-SPeps), a novel Se supplement, in mitigating apoptosis triggered by PM2.5 in A549 lung epithelial cells. The results indicate a concentration-dependent reduction in the viability of A549 cells caused by PM2.5, while Se-SPeps at concentrations of 62.5-500 µg/mL showed no significant effect. Additionally, the Se-SPeps reduced the production of ROS, proinflammatory cytokines, and apoptosis in response to PM2.5 exposure. The Se-SPeps suppressed the PM2.5-induced upregulation of Bax/Bcl-2 and caspase-3, while also restoring reductions in p-Akt in A549 cells. The antiapoptotic effects of Se-SPeps have been found to be more effective compared to SPeps, SeMet, and Na2SeO3 when evaluated at an equivalent protein or Se concentration. Our study results furnish evidence that supports the role of Se-SPeps in reducing the harmful effects of PM2.5, particularly in relation to its effect on apoptosis, oxidative stress, and inflammation.

The investigation of soybean protein isolates and soybean peptides assisting Lactobacillus plantarum K25 to inhibit Escherichia coli

Soybean protein isolates and their hydrolysates are considered as one of the most high-quality proteins among plant proteins, and current research has shown that they have potential probiotic functions. The purpose of this study was to investigate the effects of digested soybean protein isolates (dSPI) and digested soybean peptides (dPEP) on L. plantarum K25 alone and the two bacteria when co-cultured with E. coli. It showed that dSPI and dPEP promoted the growth and metabolism of L. plantarum K25, and dSPI had a better effect. Besides, dSPI and dPEP still promoted the growth and organic acid secretion of L. plantarum K25 when co-cultured with E. coli, and the dPEP treatment was more effective than dSPI. Moreover, dSPI and dPEP reduced the survival rate of E. coli when co-cultured with L. plantarum K25. These results to some extent explained the cooperation of dSPI and dPEP with L. plantarum K25 to produce acid thereby weaken the growth of E. coli.