Growth inhibition of Fusarium graminearum and deoxynivalenol detoxification by lactic acid bacteria and their application in sourdough bread

Eight lactic acid bacteria (LAB) strains were screened for their ability to inhibit Fusarium graminearum (F. graminearum) growth and remove deoxynivalenol (DON). Furthermore, the selected LAB strains were applied as starter cultures to evaluate their performance during the breadmaking process. Lactobacillus plantarum (L. plantarum) AR524 exhibited strong inhibitory activity against F. graminearum growth in a pH-dependent manner and removed up to 40.9% of DON, mainly through cell wall binding. Compared with the control, L. plantarum AR524 inhibited 60.19% of F. graminearum growth and removed 50.53% of DON during breadmaking. The texture properties of the bread were also remarkably improved by L. plantarum AR524, and its shelf life was extended from 3 days to 6 days without the application of any chemical preservatives. Therefore, L. plantarum AR524 shows excellent potential for application as a bioprotective starter culture in bakery products.     

Advancements in MXene-Polymer composites for various biomedical applications

2D materials have brought about significant technological advancements in the field of biomaterials. ‘MXene’, a ceramic-based 2D nanomaterial, is comprised of transition metal carbides, nitrides, and carbonitrides having a planar structure educed from a ceramic ‘MAX’ phase by etching out ‘A’ from it, has emerged to surpass drawbacks of conventional biomaterials. In spite of their substantial properties like large surface area, biocompatibility, hydrophilicity, metallic conductivity, and size tunability, the use of MXene is restricted in biomedical applications due of its poor stability in physiological environments, lack of sustained and controlled drug release, and low biodegradability, and these limitations lead to the notion of adopting MXene/Polymer nanocomposites. The availability of functional groups on the surface of MXenes enables polymer functionalization. These polymers functionalized MXene nanocomposites exhibit high photothermal conversion efficiency, selectivity, and stimuli-responsiveness towards malignant cells, electron sensitivity, higher antibacterial properties, and the like. This review emphasizes the innovative exemplars of polymer functionalized MXene composites for the burgeoning biomedical applications, which include controlled and sustained drug delivery, antibacterial activity, photothermal cancer therapy, unambiguous biosensing, contrast-enhanced diagnostic imaging, and bone regeneration.     

UPLC-MS/MS法测定黄酒中8种生物胺

建立黄酒中组胺、酪胺、腐胺、色胺、β-苯乙胺、尸胺、精胺、亚精胺共8种生物胺的超高效液相色谱-串联质谱检测方法.样品衍生化处理后,经C18色谱柱(100.0 mm×2.1 mm,1.7 μm)分离,0.1％甲酸溶液、0.1％甲酸-乙腈溶液作为流动相梯度洗脱,用多反应监测模式下的电喷雾正离子扫描获得质谱数据,并采用内标法...     

酸价的特异性检测方法——铜皂络合比色技术的研究进展

酸价（acid value, AV）指示油脂中游离脂肪酸(free fatty acid, FFA)含量,是油脂和含油食品最重要的质量指标和安全指标之一。针对现行AV测定标准的酸碱中和滴定技术的共性与非特异性的局限,旨在给复杂基质样品的特异性定量FFA或AV提供新思路,综述了最具代表性的FFA特异性检测技术——铜皂络合比色法的近70年的研究进展。阐述了有机相溶解液的毒性与显色强度之间的矛盾化解历程、铜盐-吡啶水相染色液的演化史、FFA的铜皂络合物结构解析过程,以及从pH调控的经典络合显色理论到以吡啶与铜离子摩尔比为核心的络合显色理论的新发展。吡啶与铜离子摩尔比为[1,3）的络合显色理论、具有增强显色强度和抑制乳化作用的乙酸盐-乙酸缓冲体系的中性染色液、低毒性溶剂替代传统高毒性苯的有机相溶解液,这三大创新使经典铜皂络合比色法突破了长期存在的试剂毒性与显色稳定性等瓶颈,成为复杂基质样品的特异性定量FFA或AV的理想方法。     

Environmental variations of trace element concentrations in Egyptian cane sugar and soil samples (Edfu factories)

Multielements, Ag, Au, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr, and Zn were estimated in the sugar cane plant (green bagasse or cane stalks and leaves), sugar cane, raw juice, mixed juice, in syrup at the different stages of sugar production (10 stages), in sugar (grades A and B), and in soil samples collected from the immediate vicinity of the cane plant roots at surface, 30 and 60 cm depths. The measurements were undertaken on a Pye Unicam SP 1900 Recording Flame Atomic Absorption Spectrophotometer. The results obtained are within the permissible safety baseline levels and in excellent agreement with the previous work done on the sugar cane plant and on the soil of the same area (Edfu) using INAA, ICP-AES and AAS (Awadallah, R. M., Sherif, M. K., Mohamed, A. E., & Grass, F. (1984). Determination of trace elements in Egyptian cane sugar by neutron activation analysis. Inter. J. Environ. Anal. Chem., 19 (1), 41–54; Awadallah, R. M., Sherif, M. K., Mohamed, A. E., & Grass, F. (1985). Determination of trace elements in Egyptian cane sugar by neutron activation analysis. J. Radioanal. Nucl. Chem. 92 (1), 7–25; Mohamed, A. E. (1986). Determination of trace elements in sugar cane refuse by instrumental neutron activation analysis. J. Radioanal. Nucl. Chem., Letters, 107 (2), 121–128; Mohamed, A. E., Awadallah, R. M., & Hassan, A. A. (1989). Determination of trace elements in Egyptian molasses by instrumental neutron activation analysis. J. Radioanal. Nuel. Chem. Articles, 129 (2), 453–457). ©     

Development of hydrocolloid microgels as starch granule mimetics: Hydrogel particles fabricated from gelatin and pectin

In this study, hydrocolloid microgels fabricated by electrostatic complexation of gelatin and pectin were developed as possible starch mimetics. The impact of covalent cross-linking on the physicochemical and structural properties of the microgels was investigated. Microgels were formed by acidifying a mixture of gelatin (0.5 wt.%) and pectin (0.01 wt.%) from pH 10 to 5 at 40 °C, followed by cross-linking with glutaraldehyde (0 to 2 mM). At low glutaraldehyde levels (< 0.5 mM), cross-linking occurred primarily within the microgels and did not affect particle dimensions, whereas at high levels (2 mM), cross-linking connected adjacent microgels leading to the formation of large flocs. Rheological and microscopic analysis showed that the degree of cross-linking impacted the thermal transitions of the microgels. A simulated oral processing study indicated that the melt-in-the-mouth behavior of the hydrocolloid microgels could be made to be similar to that of starch granules by controlling the degree of cross-linking. This study may be useful for designing starch mimetics with improved texture-modifying properties and reduced-calories.     

高效液相色谱法测定染发产品中8种染发剂

建立了高效液相色谱法同时测定8种染发剂的检测方法。样品采用甲醇超声提取,使用Purospher~?STARLPRP-18 endcapped色谱柱分离,以乙腈-0.02 mol/L乙酸铵为流动相,检测波长HC黄2为230 nm,分散蓝1为240 nm,HC红3号、分散紫1和HC橙1为250 nm,HC红1号为270 nm,HC黄4为420 nm,分散黑9为450 nm。该方法在1.0～100.0μg/mL范围内线性良好,相关系数均高于0.999,检出限为0.60～0.95 mg/kg,加标回收率为84.2%～108.4%,相对标准偏差为1.3%～4.5%。该方法简便快速、结果准确,能够满足染发产品中8种染发剂的分析要求。