Interaction between lactic acid bacteria and Polygonatum sibiricum saponins and its application to microencapsulated co-delivery

This study aimed to investigate the interaction between L.casei and L.bulgaricus with Polygonatum sibiricum saponins (PSS) and to explore the co-microencapsulation to reduce their loss rate during storage and consumption. 1% PSS was added to the culture broth, and it was found that the growth and metabolism of the strains were accelerated, especially in the compound probiotic group, indicating that PSS has potential for prebiotics. LC-MS observed significant differences in the composition and content of saponins in PSS. The metabolomics results suggest that the addition of PSS resulted in significant changes in the metabolites of probiotics. In addition, it was found that the combination of probiotics and PSS may have stronger hypoglycemic ability (ɑ-glucosidase, HepG2). Finally, a co-microencapsulated delivery system was constructed using zein and isomaltooligosaccharide. This system can achieve more excellent resistance of probiotics and PSS in gastrointestinal fluids, effectively transporting both to the small intestine.

Effects of an inoculation dose of Issatchenkia terricola WJL-G4 on physicochemical properties, active substances, and antioxidant capacity of black, red, and white currant juice

BACKGROUND

Due to the high level of organic acids - primarily citric acid - black, red, and white currants have an excessively sour taste, making taste adjustment during processing challenging. This study investigated and evaluated the effects of an inoculation dose of the acid-reducing yeast Issatchenkia terricola WJL-G4 on several aspect such as physicochemical properties, chromaticity, active substances, and antioxidant capacity. A sensory evaluation was also conducted.

RESULTS

The results indicated that, when the inoculation dose increased from 2% to 12%, the total phenol, total flavonoid, and total anthocyanin content, and antioxidant capacity in currant juice decreased. A low inoculation dose (2-4%) was beneficial for preserving the total phenol and total flavonoid content. Although the levels of most phenolic compounds decreased, the concentrations of caffeic acid, p-coumaric acid, ferulic acid, rutin, and epicatechin were significantly higher than the control after fermentation. Overall acceptability and taste scores of fermented currants improved compared with those of the control group.

CONCLUSION

This experiment provided an effective solution, with a theoretical basis, to the problems of the sour taste and harsh flavor of currant juice. © 2024 Society of Chemical Industry.

High internal phase emulsions stabilized by whey protein covalently modified with carboxymethyl cellulose: Enhanced environmental stability, storage stability and bioaccessibility

In this work, the effects of whey protein-carboxymethyl cellulose (WP-CMC) conjugates on the environmental stability, in vitro digestion stability, storage stability and bioaccessibility of high internal phase emulsions (HIPEs) were investigated. Compared to the HIPEs stabilized by the mixture of WP and CMC, the HIPEs stabilized by WP-CMC were less sensitive to environmental changes by particle size and zeta-potential, and showed better stability and bioavailability of pine nut oil as well as β-carotene during simulated gastrointestinal digestion. In addition, the inclusion function and pine nut oil oxidative stability of the HIPEs stabilized by WP-CMC were better during 16 days of storage than those of the pine nut oil and HIPEs stabilized by the mixture of WP and CMC, and also expressed higher storage stability of β-carotene. These results suggested that the conjugate-stabilized emulsions developed in this study have potential applications as protectors and carriers of liposoluble active ingredients.

Effect of citric acid on cell membrane structure and function of Issatchenkia terricola WJL-G4

AIMS

This study aimed to investigate the changes of cell membrane structure and function of Issatchenkia terricola under citric acid by performing physiological analysis.

METHODS AND RESULTS

The membrane integrity, surface hydrophobicity, structure, fluidity, apoptosis, and fatty acid methyl esters composition of I. terricola WJL-G4 cells were determined by propidium iodide staining, microbial adhesion to hydrocarbon test, transmission electron microscopy analysis, fluorescence anisotropy, flow cytometry, and gas chromatography-mass, respectively. The results showed that with the increasing of citric acid concentrations, the cell vitality, membrane integrity, and fluidity of I. terricola reduced; meanwhile, apoptosis rate, membrane permeable, hydrophobicity, and ergosterol contents augmented significantly. Compared to control, the activities of Na+, K+-ATPase, and Ca2+, Mg2+-ATPase increased by 3.73-fold and 6.70-fold, respectively, when citric acid concentration increased to 20 g l-1. The cells cracked and their cytoplasm effused when the citric acid concentration reached 80 g l-1.

CONCLUSIONS

I. terricola could successfully adjust its membrane structure and function below 60 g l-1 of citric acid. However, for citric acid concentrations above 80 g l-1, its structure and function were dramatically changed, which might result in reduced functionality.

Enhancing the functionality of plant-based Yogurt: Integration of lycopene through dual-stage fermentation of soymilk

Well-defined compositional assemblies of plant-based yogurt are of fast-growing awareness for world population concerning environmental sustainability, economic burdens and health risks. Soybean is an attractive candidate for plant yogurt, suffering from poor flavor, limited nutrition, and undesired allergens to offer healthy-functional segments. Herein, we deciphered a novel lycopene-soy yogurt by efficient two-stage fermentation of engineered B. subtilis and LAB. The fortified sogurt was ensured with redundant lycopene of 22.67 ± 2.95 mg/g DCW by engineered B. subtilis and enriched soy isoflavone from synergistic effects of engineered B. subtilis and LAB, possessing strong antioxidant capacity for upgrading functionality. Moreover, the desired pH, accelerated protein hydrolysis, enhanced amino acid availability, and expected sensory attributes cooperatively conferred lycopene-soy yogurt as healthy functional food. High potential is firstly ascribed to sequential dual culture of engineered B. subtilis and LAB in lycopene-soy yogurt, in which flavorful, hypoallergenic and antioxidative ingredients enabled functionalities for plant-based yogurt.

A Multi-Information Spreading Model for One-Time Retweet Information in Complex Networks

In the realm of online social networks, the spreading of information is influenced by a complex interplay of factors. To explore the dynamics of one-time retweet information spreading, we propose a Susceptible-Infected-Completed (SIC) multi-information spreading model. This model captures how multiple pieces of information interact in online social networks by introducing inhibiting and enhancement factors. The SIC model considers the completed state, where nodes cease to spread a particular piece of information after transmitting it. It also takes into account the impact of past and present information received from neighboring nodes, dynamically calculating the probability of nodes spreading each piece of information at any given moment. To analyze the dynamics of multiple information pieces in various scenarios, such as mutual enhancement, partial competition, complete competition, and coexistence of competition and enhancement, we conduct experiments on BA scale-free networks and the Twitter network. Our findings reveal that competing information decreases the likelihood of its spread while cooperating information amplifies the spreading of mutually beneficial content. Furthermore, the strength of the enhancement factor between different information pieces determines their spread when competition and cooperation coexist. These insights offer a fresh perspective for understanding the patterns of information propagation in multiple contexts.

Effect of Pleurotus eryngii on the Characteristics of Pork Patties during Freezing and Thawing Cycles

Temperature fluctuations severely damage the quality, oxidation stability, and structure of pork patties. This study investigated the potential reasons for Pleurotus eryngii (Pe) to protect frozen pork patties from quality degradation caused by temperature fluctuations and promoted the application of a natural ingredient. In this experiment, the pH, the water holding capacity (WHC), the properties of color and texture, the appearance, the degree of protein and lipid oxidation, and the microstructure of patties with different additions of Pe (0%, 0.25%, 0.50%, 1.00%, and 2.00%) were intensified during freezing and thawing (F-T) cycles. The results showed that patties with 0.50% Pe exhibited a distinguishable improvement in the changes of pH, WHC, color, and texture during F-T cycles (p < 0.05). With the times of F-T cycles increasing, 0.50% Pe was able to inhibit lipid oxidation of patties by decreasing the peroxide value (POV) and the thiobarbituric acid reactive substances (TBARS) value to 0.87 and 0.66-fold, respectively, compared to those in the control group. It was also able to suppress the protein oxidation of the patties with a protein sulfhydryl content increasing to 1.13-fold and a carbonyl content decreasing to 0.49-fold compared to the patties in the control group (p < 0.05) after 5 F-T cycles. In addition, the figures of appearance and microstructure of samples indicated that 0.50% Pe effectively restrained the deterioration of structure features from patties after 5 F-T cycles. Thus, the addition of Pe effectively maintained the characteristics of pork patties under F-T cycles.

Nutritional and functional insight into novel probiotic lycopene-soy milk by genome edited Bacillus subtilis

Nutritional and functional soy-based milk gains growing attention globally in food industry. However, its poor sensorial attributes, single flavor, and limited substance variety become critical issues in displaying balanced nutrition and multifunction for health. Herein, a novel probiotic lycopene-soy milk was developed by genome edited Bacillus subtilis harboring lycopene biosynthesis cassette with efficient lycopene production of 25.73 ± 1.57 mg/g DCW. Further investigation displayed desirable pH, reducing sugar, protein, total phenolic content and isoflavone for achieved milk than conventional soy milk, implying it with well-balanced nutritional quality. Notably, achieved milk exhibited stronger antioxidant capacity and higher isoflavone bioavailability for functionality. Moreover, it possessed significantly high scores for taste, appearance, and overall acceptability, suggesting its excellent sensorial attributes. To our delight, it is the first time to fortify soy-milk with probiotic and lycopene by genome edited B. subtilis to explore additive effect on improving nutritional value and functionality for food application.

Metabolomics analysis of the metabolic effects of citric acid on Issatchenkia terricola WJL-G4

In current research, yeast species Issatchenkia terricola WJL-G4 was shown to be capable of degrading citric acid, especially in the processing of fruit juice and wine. I. terricola WJL-G4 was able to use citric acid as a carbon source, but the metabolic effects of citric acid on yeast remained unclear. In this study, the metabolic effects of citric acid on I. terricola WJL-G4 were studied using liquid chromatography-mass spectrometry metabolomics technology, with glucose treatment as the control. Results showed that organic acid contents related to the extracellular tricarboxylic acid cycle (TCA) varied greatly. The metabolomics results indicated that I. terricola WJL-G4 might metabolize citric acid through the TCA pathway, and the glycolysis pathway might be inhibited; however, gluconeogenesis proceeded normally during citric acid treatment. Some fatty acids and phospholipids, along with the metabolic pathways of amino acids, vitamins, purines and nicotinamide in I. terricola WJL-G4 were also affected by the citric acid treatment. This work provided a theoretical basis for further study of the mechanism of yeast metabolism of citric acid.

GPU-enabled real-time optical frequency comb spectroscopy and a photonic readout

We describe a GPU-enabled approach for real-time optical frequency comb spectroscopy in which data is recorded, Fourier transformed, normalized, and fit at data rates up to 2.2 GB/s. As an initial demonstration we have applied this approach to rapidly interrogate the motion of an optomechanical accelerometer through the use of an electro-optic frequency comb. We note that this approach is readily amenable to both self-heterodyne and dual-comb spectrometers for molecular spectroscopy as well as a photonic readout where the approach's agility, speed, and simplicity are expected to enable future improvements and applications.

Efficacy of Postoperative Radiotherapy for Patients with New N2 Descriptors of Subclassification in Completely Resected Non-Small Cell Lung Cancer: A Real-World Study

PURPOSE/OBJECTIVE(S)

Patients with N2 non-small cell lung cancer (NSCLC) were heterogeneous groups and required further stratification. The International Society for the Study of Lung Cancer (IASLC) added new descriptors of three sub-stages for stage N2 NSCLC: N2 at a single station without N1 involvement (N2a1), N2 at a single station with N1 involvement (N2a2), and N2 at multiple stations (N2b). This study aimed to investigate the efficacy of postoperative radiotherapy (PORT) for patients with these N2 descriptors.

MATERIALS/METHODS

Patients with histologically confirmed NSCLC after complete resection and divided into PORT group and non-PORT group. The primary endpoint was DFS. The second endpoints were overall survival (OS) and locoregional recurrence-free survival (LRFS). Propensity-score matching (PSM) of baseline characteristics between the PORT and non-PORT groups was used for validation.

RESULTS

Totally 1832 patients were enrolled, including 308 N2a1 patients, 682 N2a2 patients, and 842 N2b patients. The median follow-up time was 50.1 months. The survival outcomes of the PORT and non-PORT groups before PSM were shown in Table 1. For patients with N2a1, PORT could not improve the DFS (median DFS of the PORT group and the non-PORT group: not reached vs. 46.8 months, P = 0.41), OS (P = 0.85), or LRFS (P = 0.32), which were consistent with the multivariate analysis and data after the PSM. For patients with N2a2, PORT significantly improved the DFS (median DFS 29.7 vs. 22.2 months, P = 0.02), OS (P = 0.03), and LRFS (P = 0.01). The multivariate analysis and data after the PSM confirmed the benefits in DFS and LRFS, but no benefit was observed in OS (multivariate analysis: HR 0.79, P = 0.18; median OS after PSM: 103.7 vs. 63.1 months, P = 0.34). For patients with N2b, PORT could not improve the DFS (median DFS 20.6 vs. 21.2 months, P = 0.39) but significantly improved the OS (P<0.001) and LRFS (P<0.001). However, the multivariate analysis showed that PORT significantly improved DFS (HR 0.81, P = 0.03), consistent with the data after the PSM (median DFS 20.6 and 17.6 months, P = 0.04).

CONCLUSION

PORT significantly improved the DFS and LRFS in patients with N2a2 and significantly improved the DFS, LRFS, and OS in patients with N2b. Patients with N2a1 could not benefit from PORT.

A Machine Learning Method to Predict Pathological Complete Response of Esophageal Cancer after Neoadjuvant Chemoradiotherapy with Clinicohematological Markers and MR Radiomics: A Multi-Center Study

PURPOSE/OBJECTIVE(S)

Nearly 30% of patients with local advanced esophageal cancer achieved pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT), who may benefit from organ-preservation strategy under accurate prediction of pCR. We aimed to develop and validate machine learning models based on clinicohematological markers and MR radiomics to accurately predict pCR of esophageal cancer after nCRT.

MATERIALS/METHODS

In this multi-center study, eligible patients with esophageal cancer who received baseline MR scan (T2-weighted image) and nCRT plus surgery were enrolled between September 2014 and September 2022 at institution 1 (training set) and between December 2017 and August 2021 at institution 2 (testing set). Pre-nCRT and post-nCRT blood test results were collected to calculate hematological markers. Models were constructed by machine learning based on clinicohematological markers and MR radiomics to predict pCR. Area under the curve (AUC) and cut-off analysis were used to evaluate model performances.

RESULTS

Totally 154 patients (81 in the training set and 73 in the testing set) were enrolled. The combined model integrating pre-nCRT monocyte-to-lymphocyte ratio and 6 radiomics features achieved AUC of 0.800 (95% CI 0.671-0.918) in the testing set, with sensitivity of 79.2% (95% CI 62.5%-95.8%), specificity of 83.7% (95% CI 73.5%-93.9%), positive predictive value of 76.0% (95% CI 62.5%-90.0%), and negative predictive value of 89.6% (95% CI 82.0%-95.8%).

CONCLUSION

A machine learning model based on clinicohematological markers and MR radiomics to predict pCR after nCRT for patients with esophageal cancer was developed and validated, providing a novel tool for personalized treatment. It is necessary to further validate in more large datasets.

Clinical Verification of a Nomogram Model for Prediction of Brain Metastases in Patients with pⅢA-N2 Non-Small Cell Lung Cancer

PURPOSE/OBJECTIVE(S)

Brain metastasis is one of the most common failure patterns of pⅢA-N2 non-small cell lung cancer (NSCLC) after complete resection. Prophylactic Cranial Irradiation (PCI) can improve intracranial control but not overall survival. Thus, it is particularly important to identify risk factors that are associated with brain metastasis and subsequently provide instructions for selecting patients who will optimally benefit from PCI. We have reported a nomogram model which was established based on the condition of histology, bronchial invasion, perineural invasion, and adjuvant chemotherapy, through which we can predict high risk brain metastases in patients with pⅢA-N2 NSCLC. The purpose of this study is to verify the accuracy of the nomogram model by using new cases information.

MATERIALS/METHODS

Between January 1, 2015 and December 31, 2019, patients of pⅢA-N2 NSCLC were retrospectively analyzed, to verify the consistency between actual and predictive brain metastases. The verification group was divided into two groups according to the years when genetic testing has been widely used in clinic (group1:2015-2016, group2:2017-2019). ROC curves and calibration curves were chosen for validation.

RESULTS

A total of 770 patients were enrolled in our retrospective study (group1:294 patients, group2: 476patients). The 1-, 3- and 5-year survival rates were 97.2%, 76.5%, 63.2% in group1, and 95.8%, 84.5%, 76.9% in group2, respectively. The 1-, 3- and 5-year brain metastasis rates were 7.9%, 19.7%, 25.8%, and 5.4%, 14.5%, 26.3% in group2, respectively. The AUC were 0.74 (95% CI:0.72 - 0.76) in group1, and 0.71(95% CI:0.70 - 0.73) in group 2.The 1.3.5-year calibration curves of the two groups show that the prediction is in good agreement with the actual observation.

CONCLUSION

The nomogram model can predict brain metastases high risk patients with pⅢA-N2 NSCLC. Whether gene test or not, it can be used as a basis to screening out patients of high-risk brain metastases in future clinical trials for PCI.

Overall Survival Following Salvage Thoracic Radiotherapy for Locoregional Recurrence in Patients with Completely Resected PIIIA-N2 NSCLC

PURPOSE/OBJECTIVE(S)

Locoregional recurrence is a common failure pattern for patients with completely resected pIIIA-N2 NSCLC. The salvage thoracic radiotherapy is administered in some pIIIA-N2 NSCLC patients despite postoperative radiotherapy (PORT). Salvage thoracic radiotherapy could be well tolerated and might improve survival from several small sample retrospective studies, while the high-level clinical evidence is presently lacking. We conducted this retrospective case control study to demonstrate the efficacy of salvage thoracic radiotherapy for completely resected pIIIA-N2 NSCLC patients with locoregional recurrence.

MATERIALS/METHODS

Between January 2003 and June 2019, patients who had undergone lobectomy or pneumonectomy plus mediastinal lymph node dissection or systematic sampling in our single institution were retrospectively reviewed. Those with pⅢA-N2 NSCLC that did not receive PORT and suffered locoregional recurrence being the first treatment failure were enrolled. The log-rank test was used to analyze differences between the groups, and the Kaplan-Meier method was used for survival analysis. Univariate and multivariate analyses using Cox proportional hazards regression models were performed to evaluate potential prognostic factors for survival. Statistically significant difference was set as p<0.05.

RESULTS

Of all the patients with pⅢA-N2 NSCLC reviewed, 105 suffered locoregional recurrence as the first treatment failure and didn't receive PORT. Among these patients, 51 (48.6%) received salvage thoracic radiotherapy and 54 (51.4%) did not. The median OS was 47.7 months of all patients. Survival analysis showed that the median OS in salvage thoracic radiotherapy group (69.0 months) was significantly longer than that in non-salvage thoracic radiotherapy group (37.7 months) (p = 0.029). For patients of EGFR wild type, salvage thoracic radiotherapy group had significantly longer median OS of 69.0 months compared with non-salvage thoracic radiotherapy group of 31.3 months (p = 0.004). When assessed by histological types, salvage thoracic radiotherapy significantly improved the survival of patients with lung squamous cell carcinoma with median OS not reached compared with non-salvage thoracic radiotherapy group of 31.3 months (p<0.001), while in patients with non-squamous cell carcinoma, this survival benefit was not observed (p = 0.829).

CONCLUSION

Salvage thoracic radiotherapy is an effective treatment for completely resected pIIIA-N2 NSCLC patients that have not received PORT and suffered post-operative locoregional recurrence.

4D printing of biodegradable elastomers with tailorable thermal response at physiological temperature

4D printing has a great potential for the manufacturing of soft robotics and medical devices. The alliance of digital light processing (DLP) 3D printing and novel shape-memory photopolymers allows for the fabrication of smart 4D-printed medical devices in high resolution and with tailorable functionalities. However, most of the reported 4D-printed materials are nondegradable, which limits their clinical applications. On the other hand, 4D printing of biodegradable shape-memory elastomers is highly challenging, especially when transition points close to physiological temperature and shape fixation under ambient conditions are required. Here, we report the 4D printing of biodegradable shape-memory elastomers with tailorable transition points covering physiological temperature, by using poly(D,L-lactide-co-trimethylene carbonate) methacrylates at various monomer feed ratios. After the programming step, the high-resolution DLP printed stents preserved their folded shape at room temperature, and showed efficient shape recovery at 37 °C. The materials were cytocompatible and readily degradable under physiological conditions. Furthermore, drug-loaded devices with tuneable release kinetics were realized by DLP-printing with resins containing polymers and levofloxacin or nintedanib. This study offers a new perspective for the development of next-generation 4D-printed medical devices.

Insights into the mechanism of growth and fat deposition by feeding different levels of lipid provided by transcriptome analysis of swamp eel (Monopterus albus, Zuiew 1793) liver

Lipid is an important source of energy in fish feeds, and the appropriate fat content can improve the efficiency of protein utilization. However, excessive lipid content in the feed can lead to abnormal fat deposition in fish, which has a negative effect on the growth of fish. Therefore, the effects of feed lipid levels on swamp eel were studied. Essential functional genes were screened using transcriptomics. We divided 840 fish into seven groups (four replicates). A mixture of fish and soybean oils (1:4), 0%, 2%, 4%, 6%, 8%, 10%, and 12% was added to the basic feed were named groups one to seven (L1-L7), respectively. Isonitrogenous diets were fed swamp eel for 10 weeks. Growth performance, visceral index, nutritional components, and biochemical indexes were measured and analyzed. Livers of the 0%, 6%, and 12% groups were subjected to transcriptome sequencing analysis. The results of our study showed that: the suitable lipid level for the growth of swamp eel was 7.03%; the crude fat content of whole fish, liver, intestine, muscle, and skin increased with the increase of lipid level, with some significant difference, and excess fat was deposited in skin tissue; triglyceride, total cholesterol, and free fatty acid contents increased with the increase of feed lipid level. High-density lipoprotein levels in the L3 and L4 groups were higher than in the other groups. Blood glucose concentrations in the L5, L6, and L7 groups increased; the liver tissue structure was damaged when the lipid level was too high. two-hundred-and-twenty-eight differentially expressed genes were found. Several critical pathways regulating glucose metabolism and energy balance (e.g., glycerolipid metabolism, glycolysis synthesis, degradation of ketone bodies, and Janus Kinase/Signal Transducer and Activator of Transcription signaling pathway) were enriched in swamp eel compared with the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Suitable lipid levels (7.03%) can promote the growth of swamp eel, and excessive lipid levels can cause elevated blood lipids and lead to liver cell damage. Regulatory mechanisms may involve multiple metabolic pathways for glucose and lipid metabolism in eels. This study provides new insights to explain the mechanism of fat deposition due to high levels of lipid and provides a basis for the production of efficient and environmentally friendly feed for swamp eel.

Construction of vitamin D delivery system based on pine nut oil Pickering emulsion: effect of phenols

BACKGROUND

The food industry has begun to develop foods fortified with unsaturated fatty acids; however, the susceptibility of pine nut oil to oxidation and other properties limits its use in food production. Researchers often inhibit the oxidation of oil by adding antioxidants. After the combination of polyphenols and proteins, the complex formed can improve or enhance the performance of the emulsion when it stabilizes the emulsion. Encapsulating, protecting, and controlling the release behavior of vitamin D (V_D ) during digestion through an emulsion delivery system can effectively overcome limitations such as easy degradation during processing and storage. This research uses tannic acid, gallic acid, tea polyphenol, and vanillic acid to prepare Pickering emulsions, and the type of phenolic compound is explored by multi-dimensional characterization and the amount of emulsion.

RESULTS

The influence of traits, microstructure, stability, V_D load application, and effect on the emulsion matrix's encapsulation rate and bioaccessibility is studied. A method was investigated to enhance the oxidative stability of whey protein isolate-stabilized emulsions by introducing phenol. Pickering emulsions could be obtained in the presence of phenol, while the type of phenol played a relatively important role, probably because the mechanism involved interactions between particles. Viscosity and creaming stability of emulsions increased with crosslinking of phenol in emulsions. In addition, the presence of phenol in emulsions significantly increased the bioaccessibility of encapsulated V_D after in vitro digestion.

CONCLUSION

The method presented in this study was important for improving the oxidative stability of pine nut oil emulsions, expanding the application of pine nut oil in the food industry, and providing the theoretical and application basis of application and active substance emulsion delivery systems. © 2022 Society of Chemical Industry.

Comparative study of the properties of lutein nanoliposomes coated with chitosan/(-)-epigallocatechin- 3-gallate (EGCG) complexes

BACKGROUND

Numerous positive effects have been attributed to lutein, a lipophilic nutrient, including resisting ultraviolet radiation and protecting retinal pigment epithelial (RPE) cells against blue light damage. It also has preventive effects against cardiovascular disease and cancer. However, its use could be limited by its poor stability and low bioaccessibility in the human digestive system. An encapsulation delivery system was therefore developed to resolve these limitations. In this study, chitosan-modified lutein nanoliposomes (CS-LNLs), chitosan-EGCG covalently modified lutein nanoliposomes (C-CS-EGCG-LNLs), and chitosan-EGCG noncovalently modified lutein nanoliposomes (non-C-CS-EGCG-LNLs) were designed. The average particle size, ζ-potential, and retention of lutein during storage were measured to indicate the physicochemical stability of the modified lutein nanoliposomes. The bioaccessibility of modified lutein nanoliposomes was also investigated to demonstrate the availability of lutein in the human digestive system.

RESULTS

First, Fourier-transform infrared spectroscopy (FTIR) verified that covalent bonds between chitosan and EGCG were formed. Subsequently, ζ-potential results revealed that C-CS-EGCG-LNLs had a relatively stable structure in comparison with lutein nanoliposomes (LNLs). The retention rate of lutein in CS-LNLs, C-CS-EGCG-LNLs, and non-C-CS-EGCG-LNLs was improved, especially in C-CS-EGCG-LNLs (at around 70% of lutein in initial system). An in vitro digestion experiment illustrated that CS-LNLs, C-CS-EGCG-LNLs, and non-C-CS-EGCG-LNLs presented relatively higher bioaccessibility, especially in C-CS-EGCG-LNLs (at around 33% of luein in initial system), which increased 2.5 and 1.65 times in comparison with free lutein and LNLs, respectively.

CONCLUSION

Overall, the results showed that C-CS-EGCG-LNLs presented greater physicochemical stability and bioaccessibility than LNLs, CS-LNLs, and non-C-CS-EGCG-LNLs. © 2023 Society of Chemical Industry.

Effects of saponins isolated from Polygonatum sibiricum on H2O2-induced oxidative damage in RIN-m5F cells and its protective effect on pancreas

The damage of islet cells caused by oxidative stress is closely related to diabetes. The aim of this study is to investigate the protective effect of saponins isolated from polygonatum sibiricum (PSS) on pancreas injury by using in vitro and in vivo models. The oxidative stress model of RIN-m5F cells induced by H₂O₂ was established. We found that PSS could decrease the apoptosis of RIN-m5F cells under oxidative stress. After PSS treatment, ROS and MDA levels in cells significantly decreased. Moreover, the levels of SOD and GSH were significantly increased. PSS could increase the insulin secretion level of cells under oxidative stress. The expression level of intracellular Bcl-2 increased, and the expression levels of Bax, caspase-3, caspase-8, and caspase-9 decreased significantly. In addition, the type 2 diabetes mouse model was established. The results showed that PSS had a protective effect on the injury of the pancreas in T2DM mice. PSS can relieve oxidative stress and high glucose-mediated pancreas cytotoxicity. PSS may be a promising candidate for diabetes intervention and functional foods.

Preparation of synbiotic milk powder and its effect on calcium absorption and the bone microstructure in calcium deficient mice

Calcium deficiency can lead to osteoporosis. Adequate calcium intake can improve calcium deficiency and prevent osteoporosis. Milk powder is the best source of dietary calcium supplements. Probiotics and prebiotics are considered to be beneficial substances for promoting calcium absorption. In this study, synbiotic milk powder (SMP) was prepared by combining the three, and its calcium supplementation effect and osteogenic activity were evaluated in calcium deficient mice. Through prebiotic screening experiments in vitro, after adding 1.2% iso-malto-oligosaccharide, the number of viable bacteria and the calcium enrichment of Lactobacillus plantarum JJBYG12 increased by 8.15% and 94.53% compared with those of the control group. Long-term calcium deficiency led to a significant reduction in calcium absorption and bone calcium content in mice, accompanied by structural deterioration of bone trabeculae. SMP significantly improved apparent calcium absorption, increased serum calcium and phosphorus levels, and decreased ALP activity and CTX-1 levels. In the meantime, the bone mineral density increased significantly, and the number of bone trabeculae and the proliferation and differentiation of osteoblasts also increased. SMP has good dietary calcium supplementation capacity and bone remodeling ability without significant side effects on major organs. These findings provide insights into using SMP as a dietary calcium source to improve bone health.

Single-modulator, direct frequency comb spectroscopy via serrodyne modulation

Traditional electro-optic frequency comb spectrometers rely upon the use of an acousto-optic modulator (AOM) to provide a differential frequency shift between probe and local oscillator (LO) legs of the interferometer. Here we show that these modulators can be replaced by an electro-optic phase modulator (EOM) which is driven by a sawtooth waveform to induce serrodyne modulation. This approach enables direct frequency comb spectroscopy to be performed with a single dual-drive Mach-Zehnder modulator (DD-MZM), allowing for lower differential phase noise. Further, this method allows for simpler production of integrated photonic comb spectrometers on the chip scale.

Extraction, physicochemical properties, and antioxidant activity of natural melanin from Auricularia heimuer fermentation

Introduction

Natural melanin from Auricularia heimuer have numerous beneficial biological properties, which were used as a safe and healthy colorant in several industries.

Methods

In this study, single-factor experiments, Box-Behnken design (BBD), and response surface methodology (RSM) were employed to investigate the effects of alkali-soluble pH, acid precipitation pH, and microwave time on the extraction yield of Auricularia heimuer melanin (AHM) from fermentation. Ultraviolet-visible spectrum (UV-Vis), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscope (SEM), and high-performance liquid chromatography (HPLC) were used to analyze the extracted AHM. The solubility, stability, and antioxidant activities of AHM were also measured.

Results

The results showed that alkali-soluble pH, acid precipitation pH, and microwave time significantly affected the AHM yield, with the following optimized microwave-assisted extraction conditions: alkali-soluble pH of 12.3, acid precipitation pH of 3.1, and microwave time of 53 min, resulting in an AHM extraction yield of 0.4042%. AHM exhibited a strong absorption at 210 nm, similar to melanin from other sources. FT-IR spectroscopy also revealed that AHM exhibited the three characteristic absorption peaks of natural melanin. The HPLC chromatogram profile of AHM showed a single symmetrical elution peak with a 2.435 min retention time. AHM was highly soluble in alkali solution, insoluble in distilled water and organic solvents, and demonstrated strong DPPH, OH, and ABTS free radical scavenging activities.

Discussion

This study provides technical support to optimize AHM extraction for use in the medical and food industries.

Identification of Apiaceae using ITS, ITS2 and psba-trnH barcodes

Apiaceae plants are used as medicinal herbs, pesticides, spices, and vegetables; thus, accurately identifying Apiaceae species is important. The grassland ecosystem of Heilongjiang Province in northern China has huge reserves of wild Apiaceae plants, but few reports have systematically documented their diversity. In this study, 275 Apiaceae plants of 23 species in 18 genera were collected from this area. We identified Apiaceae species by using nuclear internal transcribed spacer (ITS/ITS2) and psbA-trnH (chloroplast non-coding region) sequences based on experimental data. The identification efficiency of ITS, ITS2 and psbA-trnH sequences was determined and evaluated by sequence alignment and analysis, intraspecific and interspecific genetic distance analyses, and phylogenetic tree construction. ITS, ITS2 could distinguish 21 species from 17 genera of Apiaceae with good identification effect. When identifying species in the Apiaceae family, ITS2 can be used as the core barcode and psbA-trnH can be used as the supplementary barcode. These results can enrich the reference Apiaceae DNA barcode database.

Polygonatum sibiricum saponin Exerts Beneficial Hypoglycemic Effects in Type 2 Diabetes Mice by Improving Hepatic Insulin Resistance and Glycogen Synthesis-Related Proteins

Type 2 diabetes mellitus (T2DM) is a systemic metabolic disorder characterized by insulin deficiency and insulin resistance. Recently, it has become a significant threat to public health. Polygonatum sibiricum saponin (PSS) has potential hypoglycemic effects, but its specific mechanism needs further study. In this study, PSS significantly decreased the level of blood glucose, water intake, and the organ index in diabetic mice. Meanwhile, PSS effectively reduced the content of total triglyceride (TG), total cholesterol (TCHO), low-density lipoprotein cholesterol (LDL-C), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) in the blood, and increased the content of high-density lipoprotein cholesterol (HDL-C). This suggests that PSS could reduce the content of blood lipids and initially improve the damage of hepatocytes. We found that PSS alleviated hepatic insulin resistance, repaired islet beta cells, and enabled insulin to play its biological role normally. It also improved oral glucose tolerance and abated serum lipopolysaccharide (LPS) and glycosylated hemoglobin (HbA1c) levels in T2DM mice. Furthermore, studies have found that PSS increased the content of phosphorylated protein kinase B (AKT), thereby promoting the effect of glucose transporter 4 (GLUT-4), and activating glycogen synthase kinase 3beta (GSK-3β) and glycogen synthase (GS) proteins to promote hepatic glycogen synthesis. Finally, we found that PSS could promote the growth of beneficial bacteria such as Bifidobacterium and Lactobacillus, reduce the growth of harmful bacteria such as Enterococcus and Enterobacter, and preliminarily improve the composition of important bacteria in the intestine. These studies indicate that PSS has an excellent hypoglycemic effect, which provides a potential new treatment for T2DM and guidance for more in-depth research.

Chloroplast genome characterization of Rubus arcticus L

Rubus arcticus Linnaeus (1753) is a medicinal and edible plant in the Rosaceae with wide distribution in northeast China. The total length of the genome was 156,668 bp with a GC content of 37.1%, including a large single-copy (LSC, 85,958 bp) region, a small single-copy region (SSC, 18,756 bp), and inverted repeat (IR, 51,954 bp) regions. A total of 129 genes were identified. The numbers of protein genes tRNAs and rRNAs were 85, 36, and 8, respectively. Phylogenetic analysis indicated that R. arcticus belongs to the Rubus genus. Published R. arcticus chloroplast genomes have yielded insights into the closely related species identification, phylogenetic position and Rubus evolution.

Effect of Light Treatment on Chemical Composition of Andrographis paniculata Seedlings

Light quality consists of a spectrum of different bands, which not only affects plant, development, and primary metabolism but also affects the secondary metabolism of plants. It is an important factor affecting the content of active components of medicinal plants. The A. paniculata seedlings planted in the laboratory, as materials, were tested with red light, far red light, blue light, and ultraviolet light separately. The study assays the content of six main chemical components separately by LC-MS, observes the changes in the content, and analyzes the relationship between the light quality and the active ingredient of A. paniculata. Using the ointment yield and pH value, the fingerprint analysis method of A. paniculata standard decoction was established, and we discussed the selection of index components of A. paniculata standard decoction. It was suggested to select andrographolide as the index component. It will provide a theoretical basis for the large area cultivation of A. paniculata and optimize the quality of medicinal materials to ensure the quality of standard decoction.

Impact of Ultrasound-assisted Saline Thawing on the Technological Properties of mirror carp (Cyprinus carpio L.)

The aim of the study was to evaluate the positive effect of ultrasound-assisted saline thawing (UST) on the technological properties (water mobility, water holding capacity, colour, pH, shear force, TVB-N, oxidation reaction and microstructure) of mirror carp (Cyprinus carpio L.). The results present in the study showed that different thawing methods had negative impacts on the quality of mirror carp to varying degrees. Among them, UST samples had significant lower thawing loss, centrifugal loss and cooking loss than ultrasound thawing (UT) and air thawing (AT) samples (P < 0.05). The analysis result of low-field nuclear magnetic resonance illustrated that UST inhibited the mobility and distribution of water effectively. Decrease in shear force and TVBN values were observed in all thawing samples, and the UST samples maintained the significant better texture property and freshness than UT and AT samples did (P < 0.05). In addition, the treatment of UST obtained 1% salt concentration inhibited the oxidation reactions effectively. Investigation of the microstructure of samples demonstrated that the treatment of UST kept the relatively complete structure of tissue than other thawing methods. Therefore, UST can be an alternative strategy to the traditional thawing of meat.

Association of High Muscle Mass with Carotid Atherosclerosis: A Community-Based Population Cohort Study

OBJECTIVES

Although low muscle mass may make an under-appreciated contribution to increasing the risk of cardiovascular diseases, no prospective studies have explored the association between low muscle mass and carotid atherosclerosis. We investigated whether muscle mass was related to a higher carotid intima-media thickness (C-IMT) and carotid artery plaque in a community-based population.

METHODS

The study included 1,253 asymptomatic participants without known cardiovascular disease, who underwent carotid ultrasonography at baseline in 2013-2014 and received a re-examination in 2015-2016. The skeletal muscle mass index was estimated using a bioelectrical impedance analyzer. We assessed the relationship between the skeletal muscle mass index and the development of C-IMT and carotid plaque, both, using multivariate-adjusted logistic regression models.

RESULTS

During the follow up, 400 (51.0%) subjects with normal C-IMT at baseline developed elevated C-IMT and 215 (17.2%) subjects developed carotid plaque. The risk of elevated C-IMT occurrence linearly decreased with an increase in skeletal muscle mass index quintiles or its continuous data, after multivariate-adjustment in men and women, respectively (both P for trend < 0.05; both P < 0.05). Subgroup analyses showed that this association was BMI-dependent. Besides, there was an inverse association between a high skeletal muscle mass index and carotid artery plaque in women, but the association disappeared after multivariate adjustment. In men, the skeletal muscle mass index was not associated with the incidence of carotid plaque.

CONCLUSIONS

Skeletal muscle mass was inversely associated with the incidence of carotid atherosclerosis, suggesting muscle mass maintenance may play a role in modifying atherosclerosis.

Effect of Issatchenkia terricola WJL-G4 on Deacidification Characteristics and Antioxidant Activities of Red Raspberry Wine Processing

Our previous study isolated a novel Issatchenkia terricola WJL-G4, which exhibited a potent capability of reducing citric acid. In the current study, I. terricola WJL-G4 was applied to decrease the content of citric acid in red raspberry juice, followed by the red raspberry wine preparation by Saccharomyces cerevisiae fermentation, aiming to investigate the influence of I. terricola WJL-G4 on the physicochemical properties, organic acids, phenolic compounds and antioxidant activities during red raspberry wine processing. The results showed that after being treated with I. terricola WJL-G4, the citric acid contents in red raspberry juice decreased from 19.14 ± 0.09 to 6.62 ± 0.14 g/L, which was further declined to 5.59 ± 0.22 g/L after S. cerevisiae fermentation. Parameters related to CIELab color space, including L*, a*, b*, h°, and ∆E* exhibited the highest levels in samples after I. terricola WJL-G4 fermentation. Compared to the red raspberry wine pretreated without deacidification (RJO-SC), wine pretreated by I. terricola WJL-G4 (RJIT-SC) exhibited significantly decreased contents of gallic acid, cryptochlorogenic acid, and arbutin, while significantly increased contents of caffeic acid, sinapic acid, raspberry ketone, quercitrin, quercetin, baicalein, and rutin. Furthermore, the antioxidant activities including DPPH· and ABTS+· radical scavenging were enhanced in RJIT-SC group as compared to RJO-SC. This work revealed that I. terricola WJL-G4 had a great potential in red raspberry wine fermentation.

The effects of tislelizumab plus chemotherapy as first-line treatment on health-related quality of life of patients with advanced squamous non-small cell lung cancer: Results from a phase 3 randomized clinical trial

BACKGROUND

This study assessed the effects of adding tislelizumab to first-line standard-of- care chemotherapy on the health-related quality of life (HRQoL) of patients with advanced squamous non-small cell lung cancer (sq-NSCLC).

PATIENTS AND METHODS

Patients in this open-label, multicenter, phase 3 RATIONALE 307 trial were randomized to one of the three arms: tislelizumab plus carboplatin and paclitaxel (Arm A), tislelizumab plus carboplatin and nab-paclitaxel (Arm B), or paclitaxel plus carboplatin (Arm C). HRQoL was measured using the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 (QLQ-C30) and the EORTC Quality of Life Questionnaire Lung Cancer 13-item module (QLQ-LC13). Mean score change from baseline at Weeks 6 and 12 in the QLQ-C30's global health status/quality of life (GHS/QoL), fatigue, and physical functioning scores and QLQ-LC13 lung cancer specific subscales were examined. Time to deterioration was estimated for the GHS/QoL score.

RESULTS

A total of 355 sq-NSCLC patients received at least one dose of study drug and completed at least one HRQoL assessment. The GHS/QoL scores improved in Arms A and B relative to Arm C at Weeks 6 and 12. Arms A and B also experienced a reduction in most lung cancer-specific symptoms relative to Arm C. Time to deterioration of GHS/QoL was not reached by any of the three arms.

CONCLUSIONS

The addition of tislelizumab to platinum-based chemotherapy is associated with improvements in sq-NSCLC patients' HRQoL, especially in GHS/QoL and most importantly in lung cancer-specific symptoms including coughing, dyspnea, and hemoptysis.

Effects of Polygonatum sibiricum saponin on hyperglycemia, gut microbiota composition and metabolic profiles in type 2 diabetes mice

Diabetes is a global disease that endangers human health. As reported, saponins are effective bioactive compounds for treating type 2 diabetes mellitus (T2DM) and have nontoxic side effects. This study aimed to examine the hypoglycemic effects of Polygonatum sibiricum saponin (PSS) on T2DM mice. We found that PSS could significantly decrease the levels of insulin secretion and fasting blood glucose (FBG) in T2DM mice. And the level of triacylglycerol (TG), total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) in the blood was decreased. In contrast, the content of high-density lipoprotein cholesterol (HDL-C) was increased. 16S rDNA sequencing was used to evaluate the changes in the gut microbiota of T2DM mice, and metabolites were analyzed by metabolomic profiling. The results showed that PSS could decrease the abundance of Firmicutes in T2DM mice, increase the abundance of Bacteroidetes. It also increased the abundance of some bacterial genera (Lactobacillus, Lachnospiraceae_NK4A136_group and Intestinimonas). The phenotypes of the gut microbiome also changed accordingly. Metabolomics analysis showed that carbohydrate metabolism and amino acid metabolisms, such as L-alanine and L-glutamic acid, were greatly affected by PSS. In addition, the levels of inositol and chlorogenic acid in metabolites also increased significantly under PSS intervention. In general, PSS could exert its hypoglycemic effect, regulate the gut microbiota and affect the metabolism of T2DM mice.

Safety assessment of two strains and anti-obese effects on mice fed a high-cholesterol diet

Previous study documented that Lactobacillus paracasei S0940 and Streptococcus thermophilus ldbm1 have obvious cholesterol-lowering abilities in vitro. In this study, the safety of two strains were evaluated by nitroreductase test, hemolysis test and antibiotic sensitivity test and to evaluate the cholesterol-reducing abilities in vivo. The results indicated that two strains did not exhibit nitroreductase activities and were ɤ-hemolytic on blood agar plates. Further, both strains did not represent a health risk by antibiotic sensitivity test, and significantly reduced serum and liver cholesterol and triglyceride levels of high fat-fed mice. Compared with the high-fat model group, administration of the strains to mice fed a high-cholesterol diet increased fecal water content and fecal cholesterol and significantly improved the intestinal microbiota, which indicating that Lactobacillus paracasei S0940 and Streptococcus thermophilus ldbm1 have a positive effect on reducing cholesterol levels and may be used in functional food.

POS0787 BERBERINE MODULATE LUPUS SYNDROME VIA THE REGULATION OF GUT MICROBIOTA IN MRL/LPR MICE

Background:

Intestinal flora disorder and immune abnormalities have been reported in systemic lupus erythematosus (SLE) patients1,2. Berberine (BBR) showed significant effects in regulating the intestinal flora, repairing gut barriers and regulating immune cells3,4. While few reports mentioned the abnormal gut microbiota and metabolites in Chinese SLE patients.

Objectives:

Our investigation tried to illustrate the relationship between gut microbiota, intestinal metabolites and disease activity in Chinese SLE patients. And the effect of BBR to intestinal dysbacteriosis, multiple organ damages and over-activated immune system in MRL/Lpr mice.

Methods:

16S high-throughput (16S rRNA) sequence, qRT-PCR and gas chromatography technology were used to determine the gut microbiota and metabolites in 104 SLE patients from Affiliated Hospital of Nantong University, China. BBR was orally treated to the MRL/Lpr mice in low, medium and high doses. After 6 weeks treatment, mice were sacrificed. Serum, faeces and organs were collected for further studies.

Results:

Chinese SLE patients showed higher abundance of Bacteroidetes and lower abundance of Firmcutes. The results of qRT-PCR showed high Firmcutes/Bacteroidetes (F/B) ratio of SLE patients. The F/B ratio was negative correlated with SLE disease activity index (SLEDA) score. Almost all the tested short-chain fatty acids (SCFAs) found statistically significant results in SLE and LN (lupus nephritis) patients, especially the propanoic acid and butyric. BBR altered the relative abundance of Bacteroides and Verrucomicrobia and the butyric acid content in colon of MRL/Lpr mice. The increase of tight junction protein also indicated the gut barrier was repaired by BBR. Treg and Tfr cells in spleen and mesenteric lymph node (MLN) were increased. These results revealed a positive therapeutic effect of berberine on SLE from gut microbiota to immune status.

Conclusion:

Our study highlights current status of intestinal dysbacteriosis in Chinese patients with SLE and differences in intestinal metabolites among patients with different disease states. The regulation of intestinal flora and the repairment of gut barrier by intestinal metabolites in BBR treated mice seemed to be the factor that directed the immune responses and disease outcomes. The ultimate goal of our study was to determine the beneficial effects of regulating the gut microbiota on the treatment of SLE. The application of berberine is a relatively safe and convenient way. In the coming investigations, we plan to focus on the study of berberine and its metabolites on intestinal function and systemic immunity.

References:

[1]Guo, M. et al. Alteration in gut microbiota is associated with dysregulation of cytokines and glucocorticoid therapy in systemic lupus erythematosus. Gut microbes11, 1758-1773, doi:10.1080/19490976.2020.1768644 (2020).

[2]Mu, Q. et al. Control of lupus nephritis by changes of gut microbiota. Microbiome5, 73, doi:10.1186/s40168-017-0300-8 (2017).

[3]Habtemariam, S. Berberine pharmacology and the gut microbiota: A hidden therapeutic link. Pharmacological research155, 104722, doi:10.1016/j.phrs.2020.104722 (2020).

[4]Cui, H. et al. Berberine Regulates Treg/Th17 Balance to Treat Ulcerative Colitis Through Modulating the Gut Microbiota in the Colon. Frontiers in pharmacology9, 571, doi:10.3389/fphar.2018.00571 (2018).

Figure 1.

Disclosure of Interests:

None declared

Effect of exogenous methyl jasmonate on physiological and carotenoid composition of yellow maize sprouts under NaCl stress

Carotenoid content in maize sprouts can be increased by NaCl stress, although high NaCl concentrations negatively impact plant growth. The effects of exogenous methyl jasmonate (MeJA) on contents of carotenoid and antioxidant capacity of yellow maize sprouts under NaCl stress were investigated. Our results showed that treatments of NaCl both alone and combined with MeJA enhanced the carotenoid accumulation in maize sprouts. Moreover, the carotenoid biosynthesis related genes showed different expression patterns under addition of MeJA treatment. Additionally, the combined treatment led to significantly higher content of most carotenoids profiles and the addition of MeJA could alleviate the harmful effect caused by NaCl stress. Furthermore, the combined treatment improved antioxidant enzyme activities and radical scavenging capacity. The results implied that MeJA is kind of effective plant growth regulator for enhancing carotenoid accumulation in maize sprouts by up-regulating the expression levels of key genes involved in carotenoid biosynthetic pathway.

Adaptability of winter wheat Dongnongdongmai 1 (Triticum aestivum L.) to overwintering in alpine regions

Long winters led to a one-crop-a-year cultivation system until the winter wheat Dongnongdongmai 1 (Dn1) was successfully cultivated in northeast China. This crop variety is resistant to extremely low temperatures (-35 °C). To better understand the adaptability of winter wheat Dn1 to low temperatures, gas chromatography time-of-flight mass spectrometry (GC-TOF/MS) and metabolomics analysis was conducted on the tillering nodes of winter wheat during the overwintering period. Enzyme-regulating genes of the metabolic products were also quantitatively analysed. The metabolomic results for the tillering nodes in the overwintering period showed that disaccharides had a strong protective effect on winter wheat Dn1. Amino acid metabolism (i.e. proline, alanine and GABA) changed significantly throughout the whole wintering process, whereas organic fatty acid metabolism changed significantly only in the late stage of overwintering. This result indicates that the metabolites used by winter wheat Dn1 differ in different overwintering stages. The relationship between field temperature and metabolite changes in winter wheat Dn1 during overwintering periods is discussed, and disaccharides were identified as the osmotic stress regulators for winter wheat Dn1 during the overwintering process, as well as maintenance of the carbon and nitrogen balance by monosaccharides, amino acids and lipids for cold resistance.

Hypoglycemic effect of Taraxacum officinale root extract and its synergism with Radix Astragali extract

Taraxacum officinale (dandelion) and Radix Astragali are traditional medicinal and edible plants with high nutritional value. In this study, the synergistic hypoglycemic effect of DRE and Radix Astragali extract (RAE) was evaluated. Our results showed that water extract of dandelion (DRE-w), mainly containing polysaccharides (63.92 ± 1.82 mg/g), total flavonoid (2.57 ± 0.06 mg/g), total phenolic compounds (8.93 ± 0.34 mg/g), and saponins (0.54 ± 0.05 mg/g), exhibited significantly inhibitory effect on α-glucosidase and α-amylase. DRE-w and RAE had synergistic hypoglycemic effect; we found that DRE-w and its combination with RAE could relieve the state of insulin resistance in IR-HepG2 cells. The combination could more significantly increase the glucose consumption and intracellular glycogen content, and improve the activity of hexokinase and pyruvate kinase in IR-HepG2 cells. In summary, DRE and its combination with RAE can be developed as the drugs or functional foods for diabetes prevention and treatment.

Efficient bioconversion of raspberry ketone in Escherichia coli using fatty acids feedstocks

Background

Phenylpropanoid including raspberry ketone, is a kind of important natural plant product and widely used in pharmaceuticals, chemicals, cosmetics, and healthcare products. Bioproduction of phenylpropanoid in Escherichia coli and other microbial cell factories is an attractive approach considering the low phenylpropanoid contents in plants. However, it is usually difficult to produce high titer phenylpropanoid production when fermentation using glucose as carbon source. Developing novel bioprocess using alternative sources might provide a solution to this problem. In this study, typical phenylpropanoid raspberry ketone was used as the target product to develop a biosynthesis pathway for phenylpropanoid production from fatty acids, a promising alternative low-cost feedstock.

Results

A raspberry ketone biosynthesis module was developed and optimized by introducing 4-coumarate-CoA ligase (4CL), benzalacetone synthase (BAS), and raspberry ketone reductase (RZS) in Escherichia coli strains CR1–CR4. Then strain CR5 was developed by introducing raspberry ketone biosynthesis module into a fatty acids-utilization chassis FA09 to achieve production of raspberry ketone from fatty acids feedstock. However, the production of raspberry ketone was still limited by the low biomass and unable to substantiate whole-cell bioconversion process. Thus, a process by coordinately using fatty-acids and glycerol was developed. In addition, we systematically screened and optimized fatty acids-response promoters. The optimized promoter Pfrd3 was then successfully used for the efficient expression of key enzymes of raspberry ketone biosynthesis module during bioconversion from fatty acids. The final engineered strain CR8 could efficiently produce raspberry ketone repeatedly using bioconversion from fatty acids feedstock strategy, and was able to produce raspberry ketone to a concentration of 180.94 mg/L from soybean oil in a 1-L fermentation process.

Conclusion

Metabolically engineered Escherichia coli strains were successfully developed for raspberry ketone production from fatty acids using several strategies, including optimization of bioconversion process and fine-tuning key enzyme expression. This study provides an essential reference to establish the low-cost biological manufacture of phenylpropanoids compounds.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12934-021-01551-0.