Inhibition mechanism of rice glutelin on extruded starch digestion: From the structural properties of starch and enzyme activity.

To increase the anti-digestion ability of extruded rice starch (ERS), the influence of rice glutelin (RG) on digestive and structural characteristics of ERS were investigated. The resistant starch content increased from 4.49 % to 18.08 % as the RG content increased, while the digestion rate and digestion velocity constant were reduced by the incorporation of RG. Morphological observations showed that ERS was adhered and encapsulated by RG, and the specific area of starch granules were decreased after the addition of RG. The results of XRD and FTIR suggested that the long-range and short-range orders of ERS were improved due to the complexation with RG. The thickness of crystalline of ERS was increased while its amorphous region thickness was reduced by the supplementation with RG. The 1H NMR and 13C NMR data revealed that the branching degree and double helix content of ERS was increased by 46.24 % and 52.67 % when RG content reached to 12 %. Additionally, the addition of RG altered the molecular weight and chain length distribution of ERS. The α-amylase activity and glucoamylase activity was inhibited by RG. These results could provide a valuable basis for the application of RG in extruded rice starchy foods with lower glycemic index.

Effect of acupuncture or moxibustion at Acupoints Weizhong (BL40) or Chize (LU5) on the change in lumbar temperature in healthy adults: A study protocol for a randomized controlled trial with a 2 × 2 factorial design.

BACKGROUND: Low back pain is a common complaint among adults, and moxibustion and acupuncture are commonly used treatments. In traditional theory, Weizhong (BL40) is a popular acupoint, as supported by the saying "Yao Bei Wei Zhong Qiu." However, the difference in efficacy between acupuncture and moxibustion remains unclear. Therefore, this trial will compare the thermal effects of acupuncture and moxibustion at BL40 and Chize point (LU5) in healthy adults to provide more objective evidence regarding the relationship between the lumbar and BL40. METHOD/DESIGN: The trial will use a two-by-two factorial design, randomly assigning 140 participants to four groups (acupuncture at Weizhong (BL40), acupuncture at Chize (LU5), moxibustion at Weizhong (BL40), and moxibustion at Chize (LU5)) at a ratio of 1:1:1:1. Each group will undergo a 30-minute intervention, with the primary outcome being mean temperature in the lumbar region at the last minute of the intervention period. Secondary outcomes include maximum lumbar temperature in the lumbar region at the last minute of the intervention, average lumbar temperature and average bladder meridian temperature at specific time points during and after the intervention, and scores on the warming sensation questionnaire. Data will be analyzed on an intention-to-treat basis. DISCUSSION: This study will be the first to compare the thermal effect difference in the lumbar area between acupuncture and moxibustion in healthy individuals. The findings of this study will provide new insights for the "Yao Bei Wei Zhong Qiu" theory of traditional Chinese medicine. TRIAL REGISTRATION: ClinicalTrials.gov, Trial number: NCT05665426. Registered on 26 December 2022.

Changes in physicochemical and structural properties of pea protein during the high moisture extrusion process: Effects of carboxymethylcellulose sodium and different extrusion zones.

This study investigated effects of carboxymethylcellulose sodium (CMC) on the conformational evolution of pea protein during the high moisture extrusion process. The morphological observation showed that the addition of CMC facilitated the formation of fibrous structure of pea protein. In comparison with the pea protein in the melting zone and extrudate, the combination of CMC increased the denaturation enthalpy of pea protein by 2.09 % and 2.34 %. Compared with the material in the mixing zone, the degree of grafting between CMC and pea protein in the die was enhanced by 98.95 %. In general, the supplementation of CMC depressed the exposure of hydrophobic groups in the pea protein. In the extrusion barrel, the CMC increased the unfolding of protein molecular chains while it promoted the refolding of protein chains in the die. For the extrudate, the addition of CMC decreased the contents of α-helix and ß-sheet of pea protein by 9.67 % and 6.93 % while the contents of ß-turn and random coil were increased, leading to changes in the molecular weight distribution of protein molecules. In conclusion, these results provided new strategies toward producing the high-quality pea protein-based meat analogues by adding CMC.

Understanding effects of glutelin on physicochemical and structural properties of extruded starch and the underlying mechanism.

This work studied effects of different amounts of rice glutelin (RG) on physicochemical and structural properties of extruded rice starch (ERS) and explored the underlying mechanism of interaction between rice starch and RG upon extrusion processing. The results showed that the addition of RG altered the pasting properties, improved the viscoelastic, and increased the water mobility of ERS. The weight loss of ERS decreased from 71.40 % to 62.61 %, while the degradation temperature increased from 290.48 °C to 296.25 °C as the RG content increased from 0 % to 12 %. The complex index of extruded starch-glutelin complexes significantly elevated from 10.40 % to 35.81 % when RG content increased from 6 % to 12 %. Fourier-transform infrared spectra confirmed that RG interacted with starch via Maillard reactions, and the binding strength between RG and starch was enhanced at a higher RG content. Furthermore, results of rheological property and chemical interactions demonstrated that hydrogen bonding, hydrophobic, and electrostatic interaction were formed between RG and starch during extrusion. In summary, the obtained results of this study can further enrich the theory of starch-protein interactions and show the possibility of RG applied in the extruded starchy foods.

Insights into the interaction mechanism of glutelin and rice starch during extrusion processing: The role of specific mechanical energy.

Extruded glutelin/rice starch composites were prepared using twin-screw extrusion at various specific mechanical energies (SME), and the interaction mechanism of glutelin and rice starch was investigated at the molecular level. The results indicated that the structure of glutelin was destroyed, hydrophobic interactions and hydrogen bonds between rice starch and glutelin were formed and enhanced as the SME increased, and new hydrogen bonds were formed at the carbonyl (δ- and γ-carbons of glutelin) and C-1 of Tyr. Molecular docking studies confirmed that SME promoted the simultaneous occurrence of the Millard reaction and non-covalent reaction between glutelin and small molecular sugars produced by starch degradation, providing information on binding sites. Additionally, scanning electron microscopy (SEM) revealed dense and uniform flake-like structures induced by these binding interactions. Overall, insights into the interaction mechanism of rice starch and glutelin provide theoretical references for generating reconstituted rice products using extrusion processing.

Effect of extrusion parameters on the interaction between rice starch and glutelin in the preparation of reconstituted rice.

Reconstituted rice produced by extrusion has been attracted attention due to nutritional fortification and convenient production. Nevertheless, how to achieve desirable qualities and physicochemical properties of reconstituted rice nearly to natural rice by regulating extrusion process parameters is difficult. Herein, rice starch/glutelin mixture as raw material of reconstituted rice was extruded at varying extrusion conditions. Specific mechanical energy (SME) and sectional expansion index (SEI) dropped with rise in density (R2 = 0.9117 and 0.8207). Solubility was enhanced with increase in product temperature (R2 = 0.9085), color darkened and shifted to reddish and yellowish as extrusion temperature increased (R2 = 0.8577). These trends were well fitted by sigmoid models. Furthermore, SME enhanced hydrophobic and electrostatic interactions between rice starch and glutelin and caused the reduction in crystallinity and thermal stability, promoting the formation of a bi-continuous matrix of protein aggregates with rice starch. The obtained results can be applied to guide the production of reconstituted rice with desirable qualities.

Efficacy of electroacupuncture combined with intravenous patient-controlled analgesia after cesarean delivery: a randomized clinical trial.

BACKGROUND: Electroacupuncture is a nonpharmacologic intervention for analgesia that is widely recognized as therapy for pain. However, the clinical efficacy of electroacupuncture combined with patient-controlled intravenous analgesia for postoperative analgesia after cesarean delivery remains unclear. OBJECTIVE: This study aimed to assess the efficacy of electroacupuncture + patient-controlled intravenous analgesia for postoperative analgesia after cesarean delivery, determine the optimal frequency for the best analgesic effect, and explore the underlying mechanism of action. STUDY DESIGN: This single-center, randomized, single-blinded, sham acupuncture controlled clinical trial was conducted at a tertiary university hospital in China. Female patients who underwent cesarean delivery and received fentanyl as patient-controlled intravenous analgesia for postoperative analgesia were enrolled. Patients were after surgery randomized to receive 2 Hz electroacupuncture treatment (n=53), 20/100 Hz electroacupuncture treatment (n=53), or sham electroacupuncture treatment (n=52) (controls). The 2 electroacupuncture groups received electroacupuncture treatment at 2 or 20/100 Hz at the ST36 and SP6 points, whereas, in the sham electroacupuncture group, sham electroacupuncture was performed at nonmeridian points with nonenergized electroacupuncture instruments. Of note, 4 electroacupuncture treatments were performed in all groups at 6, 12, 24, and 48 hours after surgery. The primary outcome was the number of analgesic pump compressions at 48 hours after surgery. The secondary outcomes included number of analgesic pump compressions at 6, 12, and 24 hours after surgery; pain scores at 6, 12, 24, and 48 hours after surgery; fentanyl consumption at 48 hours after surgery; interleukin 6 and procalcitonin levels at 12 and 48 hours after surgery; and time to first exhaust. RESULTS: Overall, 174 primigravida women were included in the intention-to-treat analysis. The number of analgesic pump compressions and pain scores at all 4 time points and fentanyl consumption at 48 hours after surgery were significantly lower in the electroacupuncture treatment groups than in the sham electroacupuncture group (P<.001). CONCLUSION: Electroacupuncture + patient-controlled intravenous analgesia had a significantly better analgesic effect than sham electroacupuncture + patient-controlled intravenous analgesia within 48 hours after surgery. Thus, electroacupuncture can be considered safe and effective and may improve the efficacy of patient-controlled intravenous analgesia for pain management after cesarean delivery. Electroacupuncture can be recommended as a routine complementary therapy for pain control after cesarean delivery.