Recent Advances in the Preparation, Characterization and Applications of Locust Bean Gum-Based Films

Locust bean gum(LBG)is a typical galactomannan isolated from carob bean(Ceratonia siliqua L.)cultivated in the Mediterranean area.Due to its superior biodegradable,rheological and film-forming properties,LBG has been used alone or combined with other biopolymers(e.g.,polysaccharides,proteins and lipids)to develop films.Till now,different kinds of functional ingredients(e.g.,montmorillonite,bacteriocins,antibiotics,plant extract,essential oils and microbial cells)have been added into LBG-based films.Notably,the physical and functional properties of LBG-based films are affected by many factors,such as the structure of LBG,the type and content of other biopolymers and functional ingredients,and the physical treatment of film-forming solution.LBG-based films can be not only used as active packaging and edible coating in food industry but also used as wound dressings in pharmaceutical industry.For the first time,this review focuses on the recent advances in the preparation,characterization,physical and functional properties,and potential applications of LBG-based films.

Effects of carob-bean gum thickened formulas on infants' reflux and tolerance indices

AIM: To examine the effect of carob-bean gum(CBG) thickened-formulas on reflux and tolerance indices in infants with gastro-esophageal reflux(GER). METHODS: Fifty-six eligible infants(1-6 mo old) were randomly allocated to receive for two weeks a formula with either 0.33 g/100 m L(Formula A) or 0.45 g/100 m L(Formula B) of cold soluble CBG galactomannans respectively, or a formula with 0.45 g/100 m L of hot soluble CBG galactomannans(Formula C). No control group receiving standard formula was included in the study. Data on the following indices were obtained both at baseline and follow-up from all study participants: 24 h esophageal p H monitoring indices, anthropometrical indices(i.e., body weight and length) and tolerance indices(i.e., frequency of colics; type and frequency ofdefecations). From the eligible infants, forty seven were included in an intention-to-treat analysis to examine the effects of the two-week trial on esophageal 24 h p H monitoring, growth and tolerance indices. Repeated Measures ANOVA was used to examine the research hypothesis.RESULTS: Regarding changes in 24 h p H monitoring indices, significant decreases from baseline to followup were observed in the "Boix Ochoa Score"(i.e., an index of esophageal acid exposure), in the total number of visible refluxes and in all symptoms related indices due to acid reflux only for infants provided with Formula A, while no significant changes were observed for infants provided with Formulas B and C. In addition, the significant decreases observed in two symptoms related p H monitoring indices(i.e., "Symptom index for reflux" and "Percentage of all reflux") for infants provided with Formula A were also found to differentiate significantly compared to the changes observed in the other two groups(P = 0.048 and P = 0.014 respectively). Concerning changes in anthropometric indices, body weight significantly increased among infants provided with Formulas A and C, but not for infants provided with Formula B. As far as tolerance indices were concerned, the numbers of total and diarrheic defecations increased significantly only in infants provided with Formula B and these changes were significantly higher compared to the decreases observed in infants fed with Formulas A and C(P = 0.003 and P = 0.015 respectively. Lastly the number of colics significantly decreased in all infants, irrespective of the tested formula. CONCLUSION: Formula A(i.e., 0.33 g/100 m L of cold galactomannans) was effective in reducing certain p Hmonitoring indices of uncomplicated GER, increased body weight and was well-tolerated by infants.

Study of locust bean gum reinforced cyst-chitosan and oxidized dextran based semi-IPN cryogel dressing for hemostatic application

Severe blood loss due to traumatic injuries remains one of the leading causes of death in emergency settings.Chitosan continues to be the candidate material for hemostatic applications due to its inherent hemostatic properties.However,available chitosan-based dressings have been reported to have an acidic odor at the wound site due to the incorporation of acid based solvents for their fabrication and deformation under compression owing to low mechanical strength limiting its usability.In the present study semi-IPN cryogel was fabricated via Schiff's base cross-linking between the polyaldehyde groups of oxidized dextran and thiolated chitosan in presence of locust bean gum(LBG)known for its hydrophilicity.Polymerization at
12C yielded macroporous semi-IPN cryogels with an average pore size of 124.57±20.31 mm and 85.46%porosity.The hydrophobicity index of LBG reinforced semi-IPN cryogel was reduced 2.42 times whereas the swelling ratio was increased by 156.08%compare to control cryogel.The increased hydrophilicity and swelling ratio inflated the compressive modulus from 28.1 kPa to 33.85 for LBG reinforced semi-IPN cryogel.The structural stability and constant degradation medium pH were also recorded over a period of 12 weeks.The cryogels demonstrated lower adsorption affinity towards BSA.The cytotoxicity assays(direct,indirect)with 3T3-L1 fibroblast cells confirmed the cytocompatibility of the cryogels.The hemolysis assay showed<5%hemolysis confirming blood compatibility of the fabricated cryogel,while whole blood clotting and platelet adhesion assays confirmed the hemostatic potential of semi-IPN cryogel.

Properties and Cytocompatibility of Anti-Washout Calcium Phosphate Cement by Introducing Locust Bean Gum

The washout resistance of injectable calcium phosphate cement（CPC） is highly requisite for more widely clinical applications. In this work, locust bean gum（LBG） was used as the anti-washout agent to improve the washout resistance of CPC. The results indicated that the washout resistance was greatly improved,and meanwhile the injectability, setting time and compressive strength slightly decreased when the content of LBG was no more than 1.0%. Additionally, the CPC with 1.0% LBG exhibited good cell compatibility of the mouse bone mesenchymal stem cells（mBMSCs）. Therefore, the 1.0% LBG content was proposed to serve as a useful additive in CPC as a result of its ability to promote washout resistance, which may play an important role in clinical applications.

微波处理对刺槐豆胶多糖结构特征的影响

采用微波辅助法(microwave-assisted extraction,MAE)和热水浸提法(hot water extraction,HWE)处理刺槐豆胶,并对得到的刺槐豆胶多糖(locust bean gum polysaccharide,LBGP)进行分子量及分子量分布、糖链构象、单糖组成、糖苷键类型等一系列表征进行分析。通过比较发现,MAE-LBGP的分子量(2.744〜3.777×10^(6) g/mol)显著高于HWE-LBGP(1.222〜1.593×10^(6) g/mol),且具有更宽的分子量分布,不均一性的增强使得糖链呈现出更加多样化及更为紧密的构象特征,而HWE-LBGP的构象则表现得相对单一和松散。经由两种提取方式得到的LBGP具有相同的单糖组成种类(甘露糖和半乳糖)和糖苷键类型(1→4与1→6位连接键)。以上结果归因于在微波效应的作用下,溶剂的极化作用增强,提取能力增加,并通过增强溶剂的传质能力,获得了高分子量和更宽分布的多糖所致。本研究为微波技术在多糖提取应用方面提供了支持和帮助。

海藻酸钠与刺槐豆胶协同作用对绿豆淀粉的短期和长期老化影响

以海藻酸钠(SA)、刺槐豆胶(LBG)和绿豆淀粉(MBS)为原料,采用动态流变仪、质构仪、差示扫描量热仪、X-射线衍射仪和低场核磁共振仪探究了SA、LBG及不同复配比例的SA-LBG混合物对MBS老化的影响及其影响机理。结果显示,添加SA、LBG和SA-LBG混合物均能降低老化MBS凝胶的硬度、老化焓值、重结晶速率常数(k)、相对结晶度和水的流动性,提高其损失因子。低场核磁共振结果发现SA-LBG混合物提高了MBS凝胶的自旋-自旋弛豫时间(T_(2))。SA、LBG和SA-LBG混合物均能延缓MBS凝胶老化,其中SA-LBG混合物抗老化效果更显著。当SA与LBG以1∶1质量比复配时,SA-LBG混合物具有最强的协同作用,能有效抑制淀粉老化。这主要是由于SA与LBG的协同作用及SA、LBG和淀粉之间的氢键和静电相互作用均能减缓淀粉分子之间的相互作用,抑制淀粉的重结晶。为引入SA-LBG复合物提高MBS基食品品质提供一定的理论依据。

刺槐豆胶改良黏土强度抗压抗拉力学特性试验研究

为了研究刺槐豆胶改良黏土强度的效果,对不同养护龄期、刺槐豆胶掺量的改良黏土分别进行无侧限抗压强度试验以及抗拉试验研究。结果表明:刺槐豆胶的掺入可以显著改善黏土的抗压和抗拉性能。当养护龄期一定时,随着刺槐豆胶掺量的增加,改良黏土的抗压和抗拉强度均呈增长趋势,通过对比可知,刺槐豆胶的最优掺量为2%,试样的抗压和抗拉强度的最大值分别提升至425.74及234.61 kPa,与素土相比均提高约1.8倍;当刺槐豆胶掺量一定时,养护龄期对改良黏土的抗压、抗拉强度也有一定的影响。在刺槐豆胶掺量相同的条件下,养护龄期为7 d时,试样抗压、抗拉强度提升量最大,最大提升量分别为68.12和34.39 kPa。刺槐豆胶在土体表层形成一层胶质薄膜,并利用自身延展性填充土颗粒间孔隙,改善了土体的粒间结构,增强土体的稳定性,从而提升黏土的强度特性。随着养护龄期的增加,胶质薄膜逐渐收缩,使土体颗粒排列更加紧密,进而提高改良黏土体的无侧限抗压强度及抗拉强度。

胶粘剂组分对干法再造烟叶涂布液流变性能的影响

【背景和目的】涂布液的流变行为对干法再造烟叶的涂布加工及产品性能具有重要影响。【方法】通过流变学的稳态流变测试、动态流变测试、触变性测试及幂律方程拟合,研究胶粘剂组分CMC的黏度、取代度、用量及角豆胶用量对干法再造烟叶涂布液流变性能的影响。【结果】(1)干法再造烟叶涂布液为假塑性流体,其黏弹性表现为类液体的黏性特征;(2)干法再造烟叶涂布液的流动曲线符合Power-Law幂律模型,其假塑性特征随CMC黏度、取代度及CMC用量的增大而减弱,随角豆胶用量的增大而增强,其触变性在CMC黏度为1366 mPa·s时、取代度为0.72时、CMC用量为2.5%时、角豆胶用量为0时均为最小,表现为受剪切历史的影响最小、稳定性最高;(3)建议的CMC黏度、取代度、用量及角豆胶用量范围分别为:1300~3300 mPa·s、0.72~0.81、2.5%~3.0%、0.8%~1.0%。

天然复合多糖对戚风蛋糕品质的改良

采用蔗糖、β-葡聚糖、瓜尔胶、芸豆多糖组成的复合多糖对戚风蛋糕品质进行改善,通过测定蛋清泡沫特性、蛋糕持水性、比容、色度、气孔特性、感官评分对改善效果进行全面评价。研究发现,不同的复合多糖均对戚风蛋糕品质起到改善作用,但其作用效果和机制有所不同。β-葡聚糖可以显著提高蛋清的起泡性,并赋予蛋糕致密均匀的网状结构以增强其持水持气能力。瓜尔胶和芸豆多糖可以增强混合体系的黏度从而使蛋糕内部结构得到一定改善。同时,复合多糖有助于促进蛋糕内部发生美拉德反应,进而赋予蛋糕优异的外观和风味。总之,试验所选的4种多糖组合均对戚风蛋糕品质起到改善效果,其中蔗糖和β-葡聚糖的组合对蛋糕品质的改善效果更明显,表明β-葡聚糖具备较高的蔗糖替代潜力。

几种胶体复配对搅拌型酸奶品质的影响

以搅拌型酸奶为研究对象,在分别添加卡拉胶、刺槐豆胶、果胶3种胶体的单因素试验基础上,采用正交试验进行稳定剂的复配。试验结果表明,果胶胶体单一临界下限添加量为0.02%,卡拉胶与刺槐豆胶单一用量上限为0.05%;复配时3种胶体的最佳添加量为卡拉胶0.05%、刺槐豆胶0.03%、果胶0.05%。

槐豆胶与黄原胶的协效性研究

对槐豆胶与黄原胶的协效性进行了研究 ,结果表明 ,槐豆胶和黄原胶有较高的协效性 ,其最佳配比 (重量比 )为 2∶ 8;当混合液浓度达到 0 .5 %～ 0 .6 %时形成凝胶 。

刺槐豆胶的流变性研究

对刺槐豆胶的流变性进行了研究。研究结论表明:刺槐豆胶的粘度随浓度的升高而升高,当浓度为2%时,其粘度为46.4MPa.s;刺槐豆胶为非牛顿流体,其粘度随切变速度的增加而降低;小于80℃加热时可使刺槐豆胶的粘度增加,60℃为刺槐豆胶的最佳加热温度;冷冻对刺槐豆胶溶液的粘度没有影响,而冷藏可使刺槐豆胶的粘度有所下降;pH对刺槐豆胶溶液的粘度影响不大,即刺槐豆胶在酸性溶液和碱性溶液中较为稳定;刺槐豆胶与黄原胶无协效性。

长角豆胶复合涂膜保鲜剂常温保鲜荔枝的研究

本实验以长角豆胶与黄原胶复配胶为涂膜基质,CMC-Na、柠檬酸和吐温80等为成膜助剂,配以丁香、艾叶和大黄等具有抗菌作用的中草药制剂,配制成中草药复合涂膜保鲜剂,研究了常温(均温30.50℃)下该复合涂膜保鲜剂对荔枝品质变化的影响。结果表明:常温下经该保鲜剂涂膜保鲜的荔枝与对照组相比,果实腐烂率、失重率明显降低,呼吸强度、PPO活性及营养成分的消耗被抑制,延缓了果实的衰老过程。

亲水胶体对糯玉米汁稳定性影响

为进一步提高糯玉米汁稳定性,比较研究不同亲水胶体(黄原胶、海藻酸钠、瓜尔豆胶和刺槐豆胶)对糯玉米汁体系稳定系数、离心沉淀率、相对黏度和感官的影响,并探讨糯玉米汁体系的静电稳定性。结果表明:黄原胶具有一定的乳化效果,可以在一定程度上缓解糯玉米汁脂肪圈的形成;海藻酸钠、瓜尔豆胶和刺槐豆胶对糯玉米汁的稳定效果较好,并且随着添加量的增加,体系稳定系数和相对黏度逐渐提高;而黄原胶与海藻酸钠、瓜尔豆胶、刺槐豆胶分别以不同质量比复配时,在黄原胶、刺槐豆胶质量比1:4时,糯玉米汁体系稳定性最佳。

凝胶软糖配方的优化研究

采用质构分析、色差分析和感官评定等研究方法,研究了不同胶体(明胶、淀粉、刺槐豆胶)对软糖品质的影响。结果表明:在软糖中添加明胶,可以增加其硬度、咀嚼性和粘牙性,降低其弹性和透明度;在软糖中添加淀粉和刺槐豆胶,可以增加其硬度、咀嚼性和粘牙性,降低其透明度。通过正交实验,确定软糖的最佳配方为:明胶13g,淀粉5g,刺槐豆胶0.1g。

κ-卡拉胶与刺槐豆胶复配胶的流变学特性研究

本文分析了不同配比、浓度、pH和不同阳离子对κ-卡拉胶与刺槐豆胶复配胶粘度的影响,在此基础上研究了κ-卡拉胶与刺槐豆胶(质量比为6∶4)复配胶的静态和动态流变学特性,以及温度对粘弹性的影响。结果表明:复配胶的质量比为6∶4时存在协同增效作用,粘度最高;浓度和pH都对粘度有所影响;不同阳离子都会使复配胶的粘度降低,但KCl对粘度的影响最小。根据剪切速率与粘度的变化规律可以发现,κ-卡拉胶与刺槐豆胶复配后抗剪切能力增强。一定温度范围内,复配胶的储能模量高于单体胶的储能模量,而复配胶的损耗模量低于单体胶损耗模量,这表明复配胶的凝胶性质较两种单体胶更加明显。随着温度的升高,在65℃时损耗模量大于耗能模量,体系由凝胶状化向溶胶状态转换,确定了复配胶的融化点为65℃,这为今后的植物胶囊的制备提供了可靠理论依据。

氧化剂在刺槐豆胶浮选分离方铅矿和闪锌矿中的作用及机理

通过浮选试验、吸附量测试及X线光电子能谱分析(XPS),研究氧化剂高锰酸钾在刺槐豆胶浮选分离方铅矿和闪锌矿中的作用,考察高锰酸钾强化刺槐豆胶抑制闪锌矿的作用机理。研究结果表明:使用丁黄药为捕收剂时,方铅矿和闪锌矿可浮性均较好,刺槐豆胶对方铅矿和闪锌矿均有较强的抑制作用,二者难以分离。在有氧化剂高锰酸钾存在时,少量刺槐豆胶就能完全抑制闪锌矿的上浮,而对方铅矿的抑制作用较弱,因此联合使用高锰酸钾和刺槐豆胶能够实现方铅矿和闪锌矿的浮选分离。刺槐豆胶主要通过与闪锌矿表面生成的氧化产物发生化学反应而吸附在闪锌矿表面,高锰酸钾的加入使闪锌矿表面生成了更多的氧化产物,显著提高了刺槐豆胶在闪锌矿表面的吸附量,导致其对闪锌矿的抑制效果增强。

冷水溶胡卢巴胶的流变性研究

对胡卢巴胶冷水溶部分的流变性研究表明：浓度、剪切力、温度、pH、冻融等变化与胡卢巴胶的粘度有较大的关系。在冷水中溶解，胡卢巴胶浓度为1％时，其粘度为120mpa．s，胡卢巴胶为非“牛顿流体”，小于80℃加热，可使其粘度增高。胡卢巴胶在酸性和碱性溶液中较为稳定。冻融处理可使胡卢巴胶溶液粘度有较大幅度的提高。胡卢巴胶与黄原胶有一定协效性，但其协效性较低。

皂荚豆胶冷水溶部分和热水溶部分的流变性研究

本研究对皂荚豆胶冷水溶和热水溶部分的流变性进行了研究。研究结果表明:浓度、温度、剪切力、pH值、冻融等变化对皂荚豆胶的粘度有较大影响;皂荚豆胶与黄原胶、卡拉胶具有明显的协效性;皂荚豆胶在冷水和热水中溶解,其流变性有所不同。

刺槐豆胶与黄原胶复配体系的流变性

研究刺槐豆胶/黄原胶复配体系的流变性,并采用流变学的Cross模型进行拟合分析。结果表明:刺槐豆胶与黄原胶复配可以产生协同作用,当刺槐豆胶与黄原胶的复配体积比为4∶6时,复配体系的黏度最大,触变测试中形成的滞后环面积最大,并且在黏弹性测试中储能模量G’表现出最大值。因此,刺槐豆胶与黄原胶的最佳复配比例为体积比4∶6。对最佳比例复配体系进行不同温度处理后测试可知,最佳复配体系的最适处理温度为80℃,得到的复配体系黏度最大;复配体系的p H值在6.0~10.0之间时,其黏度变化较小,保持相对稳定。