Diego Araujo da Costa, Francine Tavares da Silva, Elder Pacheco da Cruz, Laura Martins Fonseca, Estefani Tavares Jansen, Raquel Moreira Oliveira, Andressa Salies Souza, Elessandra da Rosa Zavareze, Rui Carlos Zambiazi
Starch aerogels are a clean‐label alternative to produced active packaging aimed at preserving food products. This study aims to produce water‐absorbent and reusable aerogels from different starches and investigates their properties according to the type of starch. The aerogels are produced using different starch concentrations and evaluated in terms of morphology, density, porosity, relative crystallinity, texture properties, water absorbent capacity, reusability as water absorbent, and water absorption rate. The aerogel is applied as an absorbent of chicken breast exudate. The starches’ amylose content is 28.2%, 27.4%, 45.4%, and 30.2% for the potato, cassava, bean, and maize starches, respectively. All aerogels display physical integrity and porous structures with low density and high porosity, and their relative crystallinity decreases compared to the starches. The texture properties show great elasticity. The aerogels present high water absorption capacity, ranging from 685% to 1714%. Potato and bean starch aerogels can be reused as water absorbents 12 times showing, after the first immersion, a stable water retention rate over the reusable period. The maize starch‐based aerogel is applied as an absorbent for chicken breast exudate, reaching 39% absorption, proving to be an excellent material for application as active food packaging for fresh food preservation.
{"title":"Water‐Absorbent Biodegradable Aerogels Based on Potato, Cassava, Bean, and Maize Starches Applied in the Absorption of Chicken Exudate","authors":"Diego Araujo da Costa, Francine Tavares da Silva, Elder Pacheco da Cruz, Laura Martins Fonseca, Estefani Tavares Jansen, Raquel Moreira Oliveira, Andressa Salies Souza, Elessandra da Rosa Zavareze, Rui Carlos Zambiazi","doi":"10.1002/star.202300070","DOIUrl":"https://doi.org/10.1002/star.202300070","url":null,"abstract":"Starch aerogels are a clean‐label alternative to produced active packaging aimed at preserving food products. This study aims to produce water‐absorbent and reusable aerogels from different starches and investigates their properties according to the type of starch. The aerogels are produced using different starch concentrations and evaluated in terms of morphology, density, porosity, relative crystallinity, texture properties, water absorbent capacity, reusability as water absorbent, and water absorption rate. The aerogel is applied as an absorbent of chicken breast exudate. The starches’ amylose content is 28.2%, 27.4%, 45.4%, and 30.2% for the potato, cassava, bean, and maize starches, respectively. All aerogels display physical integrity and porous structures with low density and high porosity, and their relative crystallinity decreases compared to the starches. The texture properties show great elasticity. The aerogels present high water absorption capacity, ranging from 685% to 1714%. Potato and bean starch aerogels can be reused as water absorbents 12 times showing, after the first immersion, a stable water retention rate over the reusable period. The maize starch‐based aerogel is applied as an absorbent for chicken breast exudate, reaching 39% absorption, proving to be an excellent material for application as active food packaging for fresh food preservation.","PeriodicalId":501569,"journal":{"name":"Starch","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140625380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
César Roldan‐Cruz, Angeles García‐Hernandez, Heidi Andrea Fonseca‐Florido, Eduardo Jaime Vernon‐Carter, Jose Alvarez‐Ramirez
The thermal decomposition modeling of starch granules (rice, maize, and potato) is investigated in this work. Thermogravimetric analysis (TGA) under nitrogen conditions and different heating rates is carried out. First, a model‐free analysis is carried out to determine the variability of the activation energy with the relative conversion. The results reveal that the sequence of activation energy is rice > maize > potato. In turn, the activation energy is positively correlated (ρ = 0.98) with the relative crystallinity determined by X‐ray diffraction (XRD) analysis. Then, a fractional‐order version of the Sestak–Berggren equation is used to model the starch thermal decomposition. A least‐squares approach is used to estimate the underlying parameters by fitting non‐isothermal TGA curves. The results show that the parameters depend on the heating rate, but more strongly on the XRD relative crystallinity. Overall, the results reported in this study indicate that fractional‐order kinetics models provide an accurate description of the starch thermal degradation, without the use of the traditional TGA heuristic methods used for parameter estimation.
{"title":"Fractional‐Order Kinetics Modeling of Starch Thermal Degradation","authors":"César Roldan‐Cruz, Angeles García‐Hernandez, Heidi Andrea Fonseca‐Florido, Eduardo Jaime Vernon‐Carter, Jose Alvarez‐Ramirez","doi":"10.1002/star.202400024","DOIUrl":"https://doi.org/10.1002/star.202400024","url":null,"abstract":"The thermal decomposition modeling of starch granules (rice, maize, and potato) is investigated in this work. Thermogravimetric analysis (TGA) under nitrogen conditions and different heating rates is carried out. First, a model‐free analysis is carried out to determine the variability of the activation energy with the relative conversion. The results reveal that the sequence of activation energy is rice > maize > potato. In turn, the activation energy is positively correlated (ρ = 0.98) with the relative crystallinity determined by X‐ray diffraction (XRD) analysis. Then, a fractional‐order version of the Sestak–Berggren equation is used to model the starch thermal decomposition. A least‐squares approach is used to estimate the underlying parameters by fitting non‐isothermal TGA curves. The results show that the parameters depend on the heating rate, but more strongly on the XRD relative crystallinity. Overall, the results reported in this study indicate that fractional‐order kinetics models provide an accurate description of the starch thermal degradation, without the use of the traditional TGA heuristic methods used for parameter estimation.","PeriodicalId":501569,"journal":{"name":"Starch","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140629507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sour cassava starch is obtained by spontaneous fermentation of the starch cake immediately after being extracted, followed by sun‐drying, where oxidation reactions take place that are essential for the enhanced baking expansion of this starch. The aim of this work is to evaluate the influence of adding a different polysaccharide to the starch cake before sun‐drying in the characteristics of the obtained product. Inulin is chosen for being a soluble prebiotic fiber that may improve the nutritional quality of the starch. Inulin modifies the oxidation of the fermented starch during sun‐drying, and forms a film around the granules that hinder their swelling and water retention capacity. The crystallinity of the inulin is increased by hydration and sun‐drying. Adding inulin to the fermented starch before sun‐drying reduces its expansion capacity, but in a lower rate than when inulin is added after sun‐drying. The fermented starch sun‐dried with inulin produces a baked snack with similar texture to that of the sour starch alone, and softer than that from the native starch.
{"title":"Evaluating the Impact of Inulin Addition before Solar Drying on the Characteristics of Sour Cassava Starch as a Food Ingredient","authors":"Andrea Díaz, Cecilia Dini, María Alejandra García","doi":"10.1002/star.202300221","DOIUrl":"https://doi.org/10.1002/star.202300221","url":null,"abstract":"Sour cassava starch is obtained by spontaneous fermentation of the starch cake immediately after being extracted, followed by sun‐drying, where oxidation reactions take place that are essential for the enhanced baking expansion of this starch. The aim of this work is to evaluate the influence of adding a different polysaccharide to the starch cake before sun‐drying in the characteristics of the obtained product. Inulin is chosen for being a soluble prebiotic fiber that may improve the nutritional quality of the starch. Inulin modifies the oxidation of the fermented starch during sun‐drying, and forms a film around the granules that hinder their swelling and water retention capacity. The crystallinity of the inulin is increased by hydration and sun‐drying. Adding inulin to the fermented starch before sun‐drying reduces its expansion capacity, but in a lower rate than when inulin is added after sun‐drying. The fermented starch sun‐dried with inulin produces a baked snack with similar texture to that of the sour starch alone, and softer than that from the native starch.","PeriodicalId":501569,"journal":{"name":"Starch","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140629615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Adding hydrocolloids into native starch is a secure and valid method of physical modification. However, few research focuses on the interactions between konjac gum (KGM) and purple potato starch (PPS). In this study, the effects of KGM on the physicochemical, rheological, textural properties, and in vitro digestibility of PPS are evaluated. The swelling power, solubility, transparency, zeta potential value, particle size, gel adhesiveness, and cohesiveness of PPS are enhanced with increasing KGM content. The results show the combination of PPS and KGM exhibits a higher adhesiveness and a denser structure than that of PPS alone. Static rheological analysis shows PPS/KGM composites exhibit pseudoplastic and shear thinning enhancement behaviors with the rise of the KGM content from 0% to 2.5%. Dynamic rheological analysis reveals that storage modulus (G') > loss modulus (G″), mainly showing elastic behavior, and G′, G″, and the loss tangent (tan δ) increase with the rise of the KGM content from 0% to 2.5%. Fourier transform infrared spectroscopy analysis shows stronger hydrogen bonding of PPS/KGM complexes compared to PPS only. Moreover, KGM increases the contents of resistant starch. All these findings indicate that KGM can improve the functional properties of PPS.
{"title":"Effects of Konjac Gum on Physicochemical, Rheological, Textural Properties, and In Vitro Digestibility of Purple Potato Starch","authors":"Dan He, Yue Li, Yinglong Wu","doi":"10.1002/star.202300076","DOIUrl":"https://doi.org/10.1002/star.202300076","url":null,"abstract":"Adding hydrocolloids into native starch is a secure and valid method of physical modification. However, few research focuses on the interactions between konjac gum (KGM) and purple potato starch (PPS). In this study, the effects of KGM on the physicochemical, rheological, textural properties, and in vitro digestibility of PPS are evaluated. The swelling power, solubility, transparency, zeta potential value, particle size, gel adhesiveness, and cohesiveness of PPS are enhanced with increasing KGM content. The results show the combination of PPS and KGM exhibits a higher adhesiveness and a denser structure than that of PPS alone. Static rheological analysis shows PPS/KGM composites exhibit pseudoplastic and shear thinning enhancement behaviors with the rise of the KGM content from 0% to 2.5%. Dynamic rheological analysis reveals that storage modulus (<jats:italic>G</jats:italic>') > loss modulus (<jats:italic>G</jats:italic>″), mainly showing elastic behavior, and <jats:italic>G</jats:italic>′, <jats:italic>G</jats:italic>″, and the loss tangent (tan <jats:italic>δ</jats:italic>) increase with the rise of the KGM content from 0% to 2.5%. Fourier transform infrared spectroscopy analysis shows stronger hydrogen bonding of PPS/KGM complexes compared to PPS only. Moreover, KGM increases the contents of resistant starch. All these findings indicate that KGM can improve the functional properties of PPS.","PeriodicalId":501569,"journal":{"name":"Starch","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140625387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Raw and cooked (autoclaved) green bananas are fed to rats for 4 weeks and their effects on cecal microbiota and biomarkers of fermentation are evaluated and compared with those of potato starch, which is rich in RS. Relative abundances of genera Lachnospiraceae_NK4A136_group and Roseburia, and species Bifidobacterium pseudolongum in rat cecum are higher in the raw green banana group with higher RS consumption than in the control group. The raw green banana group shows higher cecal acetate production and similarly high levels of cecal n‐butyrate production than that in the potato starch group. In the autoclaved green banana group, the cecal microbial composition is altered and the relative abundance of family Ruminococcaceae increased. Additionally, the molar proportion of n‐butyrate in the cecum of the autoclaved green banana group is higher than that in the control group. The levels of cecal mucin and IgA in the raw green banana and potato starch groups are found to be higher compared to those observed in the control and autoclaved green banana groups. Therefore, raw and autoclaved green bananas can alter cecal microbial composition and thus exhibit beneficial intestinal fermentation characteristics.
{"title":"Effect of Raw and Cooked Green Bananas on Cecal Fermentation Characteristics in Rats","authors":"Ryuji Nagata, Naoki Fukuma, Naoto Hashimoto, Kenichiro Shimada, Yasunori Nakayama, Kyu‐Ho Han, Michihiro Fukushima","doi":"10.1002/star.202300180","DOIUrl":"https://doi.org/10.1002/star.202300180","url":null,"abstract":"Raw and cooked (autoclaved) green bananas are fed to rats for 4 weeks and their effects on cecal microbiota and biomarkers of fermentation are evaluated and compared with those of potato starch, which is rich in RS. Relative abundances of genera <jats:italic>Lachnospiraceae_NK4A136_group</jats:italic> and <jats:italic>Roseburia</jats:italic>, and species <jats:italic>Bifidobacterium pseudolongum</jats:italic> in rat cecum are higher in the raw green banana group with higher RS consumption than in the control group. The raw green banana group shows higher cecal acetate production and similarly high levels of cecal <jats:italic>n</jats:italic>‐butyrate production than that in the potato starch group. In the autoclaved green banana group, the cecal microbial composition is altered and the relative abundance of family <jats:italic>Ruminococcaceae</jats:italic> increased. Additionally, the molar proportion of <jats:italic>n</jats:italic>‐butyrate in the cecum of the autoclaved green banana group is higher than that in the control group. The levels of cecal mucin and IgA in the raw green banana and potato starch groups are found to be higher compared to those observed in the control and autoclaved green banana groups. Therefore, raw and autoclaved green bananas can alter cecal microbial composition and thus exhibit beneficial intestinal fermentation characteristics.","PeriodicalId":501569,"journal":{"name":"Starch","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140586104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sweet potato is one of the essential starch materials for food and feed world widely. However, its application is limited by the low viscosity and poor stability of native starches. Herein, sweet potato starch is modified by octenyl succinic anhydride (OSA) in the aqueous system. The optimization for esterification is studied using response surface methodology. The characteristics of OSA‐modified sweet potato starch are investigated, and its emulsifying properties as macromolecular and particulate stabilizers in the oil‐in‐water systems are compared. The optimal process conditions for OSA modification are: reaction time 4.0 h, temperature 38.8 °C, pH of the reaction system 8.2, starch concentration 32.2%, OSA amount 3.0%. The degree of substitution is 0.0185, and reaction efficiency is 79.7% under the optimum conditions. The new peaks at 1725 and 1573 cm−1 are observed by Fourier transform infrared spectroscopy. Compared with native starch, OSA‐modified sweet potato starch exhibits higher viscosities, improved paste clarity, and decreased retrogradation. The confocal laser scanning microscope results show that the gelatinized starch macromolecule and ungelatinized starch particles can arrange at the water–oil interface. The OSA‐modified sweet potato starch is both an effective macromolecular emulsifier and a particulate stabilizer, effectively stabilizing oil‐in‐water emulsions.
{"title":"Comparative Study on the Emulsification of Octenyl Succinic Anhydride Modified Sweet Potato Starch: As Macromolecular and Particulate Stabilizers","authors":"Jianyang Chen, Wei Zhu, Qing Chen, Xiaoyan Song","doi":"10.1002/star.202400027","DOIUrl":"https://doi.org/10.1002/star.202400027","url":null,"abstract":"Sweet potato is one of the essential starch materials for food and feed world widely. However, its application is limited by the low viscosity and poor stability of native starches. Herein, sweet potato starch is modified by octenyl succinic anhydride (OSA) in the aqueous system. The optimization for esterification is studied using response surface methodology. The characteristics of OSA‐modified sweet potato starch are investigated, and its emulsifying properties as macromolecular and particulate stabilizers in the oil‐in‐water systems are compared. The optimal process conditions for OSA modification are: reaction time 4.0 h, temperature 38.8 °C, pH of the reaction system 8.2, starch concentration 32.2%, OSA amount 3.0%. The degree of substitution is 0.0185, and reaction efficiency is 79.7% under the optimum conditions. The new peaks at 1725 and 1573 cm<jats:sup>−1</jats:sup> are observed by Fourier transform infrared spectroscopy. Compared with native starch, OSA‐modified sweet potato starch exhibits higher viscosities, improved paste clarity, and decreased retrogradation. The confocal laser scanning microscope results show that the gelatinized starch macromolecule and ungelatinized starch particles can arrange at the water–oil interface. The OSA‐modified sweet potato starch is both an effective macromolecular emulsifier and a particulate stabilizer, effectively stabilizing oil‐in‐water emulsions.","PeriodicalId":501569,"journal":{"name":"Starch","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140586304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Olalekan Adeyinka Balogun‐Agbaje, Michael Ayodele Odeniyi
Starches from underutilized sources such as Bambara nut (BAM) and pigeon pea (PP) can serve as new sources of starch. Starch nanoparticles (SNP) of BAM (BAMnp) and PP (PPnp) are prepared by nanoprecipitation. The physicochemical and pasting properties of the native and SNP are evaluated. The scanning electron microscopy, fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), drug loading, and release studies of curcumin‐loaded starches and SNP are carried out. The flow, swelling, and solubility of the native starches improve with nanoparticle fabrication. Setback viscosities of the starches are in the order PPnp < BAMnp < PP < BAM. The integrity of the starch granules is maintained after modification. The FTIR of loaded starches shows no interaction between the entities. Reduction in crystallinity of the SNP is observed in the XRD diffractogram. The drug loading efficiency of BAM, PP, BAMnp, and PPnp are 48.55 ± 0.11, 49.00 ± 0.11, 55.44 ± 0.40, and 54.72 ± 0.11, respectively. The drug release is improved when curcumin is loaded on the SNP. The release after 6 h is 33%, 25%, and 2% for BAMnp, PPnp, and pure curcumin, respectively. The properties of the SNP showed that they are potential candidates for the delivery of curcumin, a poorly water soluble drug.
班巴拉坚果（BAM）和鸽子豆（PP）等未充分利用的淀粉可作为新的淀粉来源。通过纳米沉淀法制备了班巴拉坚果（BAMnp）和鸽子豆（PPnp）的淀粉纳米颗粒（SNP）。对原生淀粉纳米颗粒和 SNP 的物理化学和粘贴性能进行了评估。对姜黄素负载淀粉和 SNP 进行了扫描电子显微镜、傅立叶变换红外光谱（FTIR）、X 射线衍射（XRD）、药物负载和释放研究。随着纳米粒子的制造，原生淀粉的流动性、溶胀性和溶解性都得到了改善。淀粉的回流粘度依次为 PPnp < BAMnp < PP < BAM。改性后的淀粉颗粒保持了完整性。负载淀粉的傅立叶变换红外光谱（FTIR）显示实体之间没有相互作用。XRD 衍射图显示 SNP 的结晶度降低。BAM、PP、BAMnp 和 PPnp 的药物负载效率分别为 48.55 ± 0.11、49.00 ± 0.11、55.44 ± 0.40 和 54.72 ± 0.11。在 SNP 上负载姜黄素后，药物释放得到改善。6 小时后，BAMnp、PPnp 和纯姜黄素的释放率分别为 33%、25% 和 2%。SNP 的特性表明，它们是输送姜黄素（一种水溶性较差的药物）的潜在候选材料。
{"title":"Characterization and Drug Release Properties of Curcumin Loaded Native and Nano‐Sized Starches of Pigeon Pea (Cajanus cajan) and Bambara Nut (Vigna subterranean)","authors":"Olalekan Adeyinka Balogun‐Agbaje, Michael Ayodele Odeniyi","doi":"10.1002/star.202400022","DOIUrl":"https://doi.org/10.1002/star.202400022","url":null,"abstract":"Starches from underutilized sources such as Bambara nut (BAM) and pigeon pea (PP) can serve as new sources of starch. Starch nanoparticles (SNP) of BAM (BAMnp) and PP (PPnp) are prepared by nanoprecipitation. The physicochemical and pasting properties of the native and SNP are evaluated. The scanning electron microscopy, fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), drug loading, and release studies of curcumin‐loaded starches and SNP are carried out. The flow, swelling, and solubility of the native starches improve with nanoparticle fabrication. Setback viscosities of the starches are in the order PPnp < BAMnp < PP < BAM. The integrity of the starch granules is maintained after modification. The FTIR of loaded starches shows no interaction between the entities. Reduction in crystallinity of the SNP is observed in the XRD diffractogram. The drug loading efficiency of BAM, PP, BAMnp, and PPnp are 48.55 ± 0.11, 49.00 ± 0.11, 55.44 ± 0.40, and 54.72 ± 0.11, respectively. The drug release is improved when curcumin is loaded on the SNP. The release after 6 h is 33%, 25%, and 2% for BAMnp, PPnp, and pure curcumin, respectively. The properties of the SNP showed that they are potential candidates for the delivery of curcumin, a poorly water soluble drug.","PeriodicalId":501569,"journal":{"name":"Starch","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140582012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mieow Kee Chan, Chan Chin Wang, Yi Shen Tee, Mei Hui Tan, Shamini Janasekaran, Izhar Abd Aziz, Shahrul Irwan Musa, Muhammad Ridzuan Mohammed Khir
The dependency of 3D printing on thermoplastics releases volatile organic compounds and contributes to global microplastic pollution. The objective of this study is to explore the potential of hydro‐degradable starch‐based composite as a 3D printing material by considering its printability, hydro‐degradability, and strength. Starch is hydro degradable, however, it exhibits low strength thus attempts are made to improve the strength of the composite by starch coating and using lemongrass essential oil (LEO) as an additive. The result shows that 0.2 wt% of LEO increased the strength of starch/wood powder/glycerol/LEO (SWGL) composite by 55% and reduced the contact angle by ≈27° compared to the control. Starch coating increases the strength of the composite by filling up the voids in the structure and producing an integrated homogeneous surface. The SWGL composites exhibit good hydro degradability, especially under acidic conditions, due to the high‐water sorption rate and solubility. The printability of SWGL composites is good where the objects are printed as designed with the aid of a heating chamber. In conclusion, SWGL with 0.5wt% LEO is suitable for real‐life application as the 3D printing material for photo frames and souvenirs due to its good hydro degradability and moderate tensile strength.
三维打印对热塑性塑料的依赖会释放出挥发性有机化合物，造成全球微塑料污染。本研究旨在通过考虑淀粉基复合材料的可打印性、水降解性和强度，探索其作为三维打印材料的潜力。淀粉可水解降解，但强度较低，因此尝试通过淀粉涂层和使用柠檬草精油（LEO）作为添加剂来提高复合材料的强度。结果表明，与对照组相比，0.2 wt%的柠檬草精油可使淀粉/木粉/甘油/柠檬草精油（SWGL）复合材料的强度提高 55%，接触角减小 ≈27°。淀粉涂层可填充结构中的空隙并产生一个整体均匀的表面，从而提高复合材料的强度。由于高吸水率和高溶解性，SWGL 复合材料具有良好的水降解性，尤其是在酸性条件下。SWGL 复合材料的可印刷性很好，在加热室的帮助下，物体可以按照设计进行印刷。总之，含 0.5wt% LEO 的 SWGL 具有良好的水降解性和适中的拉伸强度，适合在现实生活中用作相框和纪念品的 3D 打印材料。
{"title":"Starch/Wood Powder/Glycerol/Lemongrass Essential Oil Composite as Hydro‐Degradable Materials for 3D Printing","authors":"Mieow Kee Chan, Chan Chin Wang, Yi Shen Tee, Mei Hui Tan, Shamini Janasekaran, Izhar Abd Aziz, Shahrul Irwan Musa, Muhammad Ridzuan Mohammed Khir","doi":"10.1002/star.202300108","DOIUrl":"https://doi.org/10.1002/star.202300108","url":null,"abstract":"The dependency of 3D printing on thermoplastics releases volatile organic compounds and contributes to global microplastic pollution. The objective of this study is to explore the potential of hydro‐degradable starch‐based composite as a 3D printing material by considering its printability, hydro‐degradability, and strength. Starch is hydro degradable, however, it exhibits low strength thus attempts are made to improve the strength of the composite by starch coating and using lemongrass essential oil (LEO) as an additive. The result shows that 0.2 wt% of LEO increased the strength of starch/wood powder/glycerol/LEO (SWGL) composite by 55% and reduced the contact angle by ≈27° compared to the control. Starch coating increases the strength of the composite by filling up the voids in the structure and producing an integrated homogeneous surface. The SWGL composites exhibit good hydro degradability, especially under acidic conditions, due to the high‐water sorption rate and solubility. The printability of SWGL composites is good where the objects are printed as designed with the aid of a heating chamber. In conclusion, SWGL with 0.5wt% LEO is suitable for real‐life application as the 3D printing material for photo frames and souvenirs due to its good hydro degradability and moderate tensile strength.","PeriodicalId":501569,"journal":{"name":"Starch","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140581866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lin Lin, Ruiqi Li, Ziyu Wang, Jing Yuan, Xiaojun Hu
A novel thermostable type I pullulanase gene (named pulGSM) is cloned from Geobacillus stearothermophilus DSMZ456. The purified PulGSM shows optimal activity at pH 6.0 and 65 °C. Protein engineering method (site‐directed mutagenesis and enzyme immobilization) is used to further improve the thermostability and catalytic efficiency of PulGSM. Through site‐directed mutagenesis, three mutants (carrying the mutations L211C, E306I and R471E named PulGSM‐M211, PulGSM‐M306 and PulGSM‐M471) are generated and characterized in detail. As showing the best enzymatic properties, PulGSM‐M471 is directly immobilized on epoxy‐functionalized supports to obtain the immobilized enzyme lx‐PulGSM‐M471. The temperature tolerance results show an enhanced T1/2 of 6.5 h (mutated PulGSM‐M471) and 8.5 h (mutated and immobilized lx‐PulGSM‐M471) at 70 °C in comparison to the wild type (4 h). Compared to the commercial pullulanase from Bacillus acidopullulyticus (PDB:2WAN), PulGSM or PulGSM‐M471 can be used directly in maize starch saccharification process without adjusting the pH, which reduces cost and improves efficiency.
{"title":"Protein Engineering of Novel Thermostable Pullulanase from Geobacillus stearothermophilus and Starch Saccharification Application","authors":"Lin Lin, Ruiqi Li, Ziyu Wang, Jing Yuan, Xiaojun Hu","doi":"10.1002/star.202300227","DOIUrl":"https://doi.org/10.1002/star.202300227","url":null,"abstract":"A novel thermostable type I pullulanase gene (named <jats:italic>pul<jats:sub>GSM</jats:sub></jats:italic>) is cloned from <jats:italic>Geobacillus stearothermophilus</jats:italic> DSMZ456. The purified Pul<jats:sub>GSM</jats:sub> shows optimal activity at pH 6.0 and 65 °C. Protein engineering method (site‐directed mutagenesis and enzyme immobilization) is used to further improve the thermostability and catalytic efficiency of Pul<jats:sub>GSM</jats:sub>. Through site‐directed mutagenesis, three mutants (carrying the mutations L211C, E306I and R471E named Pul<jats:sub>GSM</jats:sub>‐M211, Pul<jats:sub>GSM</jats:sub>‐M306 and Pul<jats:sub>GSM</jats:sub>‐M471) are generated and characterized in detail. As showing the best enzymatic properties, Pul<jats:sub>GSM</jats:sub>‐M471 is directly immobilized on epoxy‐functionalized supports to obtain the immobilized enzyme lx‐Pul<jats:sub>GSM</jats:sub>‐M471. The temperature tolerance results show an enhanced T<jats:sub>1/2</jats:sub> of 6.5 h (mutated Pul<jats:sub>GSM</jats:sub>‐M471) and 8.5 h (mutated and immobilized lx‐Pul<jats:sub>GSM</jats:sub>‐M471) at 70 °C in comparison to the wild type (4 h). Compared to the commercial pullulanase from <jats:italic>Bacillus acidopullulyticus</jats:italic> (PDB:2WAN), Pul<jats:sub>GSM</jats:sub> or Pul<jats:sub>GSM</jats:sub>‐M471 can be used directly in maize starch saccharification process without adjusting the pH, which reduces cost and improves efficiency.","PeriodicalId":501569,"journal":{"name":"Starch","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140582013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Non‐conventional starch sources have emerged as an interest due to their inherent physicochemical properties similar to conventional starches. This study aimed to enhance the value of non‐conventional litchi seed starch by employing anoxidizing process using different concentrations of sodium hypochlorite (NaOCl)(0.5, 1.5, 2.5, 3.5, 4.5%). The carbonyl and carboxyl content of oxidized starch was in the range of (0.019 – 0.323%) and (0.044 – 0.425%) showing an increase with the increasing concentration of NaOCl. The native and oxidized starches were further characterized for their functional and structural properties. The amylose content of native starch was 21.52% which was reduced to (19.34 – 13.43%) upon oxidation. The water and oil absorption capacities increased with theoxidation level. The swelling power(g/g) and solubility (g/100g) for native starch were 16.17 and 16.20 and 9.5 and 31.40 for modified starch. The oxidized starch produced clearer pastes. Scanning electron microscopy revealed surface erosion and cavities in oxidized starch granulesat higher concentrations. The oxidized starch showed higher relative crystallinity. FTIR was further used to assess structural changes in starches. Therefore, it can be concluded that oxidation significantly altered the characteristics of litchi seed starch, expanding its potential applications in various industries.
{"title":"Physicochemical and Morphological Properties of Litchi Seed Starch Oxidized by Different Levels of Sodium Hypochlorite","authors":"Jashanveer Kaur, Prerna Gupta, Anjan Borah","doi":"10.1002/star.202300119","DOIUrl":"https://doi.org/10.1002/star.202300119","url":null,"abstract":"Non‐conventional starch sources have emerged as an interest due to their inherent physicochemical properties similar to conventional starches. This study aimed to enhance the value of non‐conventional litchi seed starch by employing anoxidizing process using different concentrations of sodium hypochlorite (NaOCl)(0.5, 1.5, 2.5, 3.5, 4.5%). The carbonyl and carboxyl content of oxidized starch was in the range of (0.019 – 0.323%) and (0.044 – 0.425%) showing an increase with the increasing concentration of NaOCl. The native and oxidized starches were further characterized for their functional and structural properties. The amylose content of native starch was 21.52% which was reduced to (19.34 – 13.43%) upon oxidation. The water and oil absorption capacities increased with theoxidation level. The swelling power(g/g) and solubility (g/100g) for native starch were 16.17 and 16.20 and 9.5 and 31.40 for modified starch. The oxidized starch produced clearer pastes. Scanning electron microscopy revealed surface erosion and cavities in oxidized starch granulesat higher concentrations. The oxidized starch showed higher relative crystallinity. FTIR was further used to assess structural changes in starches. Therefore, it can be concluded that oxidation significantly altered the characteristics of litchi seed starch, expanding its potential applications in various industries.","PeriodicalId":501569,"journal":{"name":"Starch","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140582010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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