RESUMEN
To enrich the application of nanocomposite hydrogels, we introduced two types of nanocellulose (CNC, cellulose nanocrystals; CNF, cellulose nanofibers) into the soy protein isolate(SPI)- konjac glucomannan (KGM) composite hydrogel system, respectively. The similarities and differences between the two types of nanocellulose as textural improvers of composite gels were successfully explored, and a model was developed to elaborate their interaction mechanisms. Appropriate levels of CNC (1.0 %) and CNF (0.75 %) prolonged SPI denaturation within the system, exposed more buried functional groups, improved molecular interactions, and strengthened the honeycomb structural skeleton formed by KGM. The addition of CNC resulted in greater gel strength (SKC1 2708.53 g vs. Control 810.35 g), while the addition of CNF improved the elasticity (SKF0.75 1940.24 g vs. Control 405.34 g). This was mainly attributed to the reinforcement of the honeycomb-structured, water binding and trapping, and the synergistic effect of covalent (disulfide bonds) and non-covalent interactions (hydrogen bonds, ionic bonds) within the gel network. However, the balance and interactions between proteins and polysaccharides were disrupted in the composite system with excessive CNF addition (≥0.75 %), which broken the stability of the honeycomb-like structure. We expect this study will draw attention on potential applications of CNC and CNF in protein-polysaccharide binary systems and facilitate the creation of novel, superior, mechanically strength-regulated nanofiber composite gels.
Asunto(s)
Hidrogeles , Proteínas de Soja , Hidrogeles/química , Celulosa/química , Mananos/química , CetonasRESUMEN
To investigate the change of ionic strength on the gel characteristics during the processing of mung bean protein-based foods, the effects of NaCl and CaCl2 at different concentrations (0-0.005 g/mL) on the properties of mung bean protein (MBP) and wheat gluten (WG) composite protein gel were studied. The results showed that low concentration (0.001-0.002 g/mL) could significantly improve the water holding capacity (WHC), storage modulus (G') and texture properties of composite protein gel (MBP/WG), while the surface hydrophobicity (H0) and solubility were significantly decreased (P < 0.05). With the increase of ion concentration, the secondary structures of MBP/WG shifted from α-helix to ß-sheet, and the fluorescence spectra also showed fluorescence quenching phenomenon. By analyzing the intermolecular forces of MBP/WG, it was found that with the addition of salt ions, the hydrogen bonds was weakened and the electrostatic interactions, hydrophobic interactions and disulfide bonds were enhanced, which in turn the aggregation behavior of MBP/WG composite protein gel was affected and larger aggregates between the proteins were formed. It could be also demonstrated that the gel network was denser due to the addition of these large aggregates, thus the gel properties of MBP/WG was improved. However, too many salt ions could disrupt the stable network structure of protein gel. This study can provide theoretical support to expand the development of new mung bean protein products.
Asunto(s)
Vigna , Triticum , Glútenes , Cloruro de Sodio , Iones , Cloruro de Sodio DietéticoRESUMEN
Idiopathic granulomatous mastitis (IGM) is a chronic inflammatory breast disease. Currently, there is no international standard for steroid use in IGM, particularly for intralesional steroid injections. This study aimed to determine whether patients with IGM who received oral steroids could benefit from intralesional steroid injection. We analyzed 62 patients with IGM whose main clinical presentation was mastitis masses and who received preoperative steroid therapy. Group A (n = 34) received combined steroid treatment: oral steroids (starting dose, 0.25 mg/kg/d; tapered off) and intralesional steroid injection (20 mg per session). Group B (n = 28) received oral steroids only (starting dose, 0.5 mg/kg/d; tapered off). Both groups underwent lumpectomy at the end of steroid treatment. We analyzed the preoperative treatment time, preoperative mass maximum diameter reduction rate, side effects, postoperative satisfaction, and rate of IGM recurrence. The mean age of the 62 participants was 33.6 ± 2.3 (range, 26-46) years, and all had unilateral disease. We found that oral steroids combined with intralesional steroid injection yielded better therapeutic effects than did oral steroids alone. The median maximum diameter reduction of the breast mass was 52.06% in group A and 30.00% in group B (P = .002). Moreover, the use of intralesional steroids reduced the duration of oral steroid use; the median durations of preoperative steroid therapy were 4 and 7 weeks in groups A and B, respectively (P < .001). Group A patients were more satisfied (P = .035) with the postoperative results, including postoperative appearance and function. No statistically significant between-group differences were noted regarding side effects and recurrence rates. Preoperative administration of oral steroids combined with intralesional steroid injection yielded better therapeutic effects than did oral steroids alone and may be an effective future treatment for IGM.