Characterization of molecular properties of wheat starch from three different types of breads using asymmetric flow field-flow fractionation (AF4)

Physico-chemical and nutritional properties of breadfruit pulp and peel flours: Insights into starch molecular characteristics and their impact on starch digestibility

Breadfruit is an underutilized crop with significant nutritional potential as a gluten-free starch-rich food ingredient. This study evaluated the chemical, molecular, structural, and nutritional properties of breadfruit (BF) flours derived from both pulp and peel, along with banana flour as a reference. Starch digestibility, estimated in vitro, was linked to these properties. Both BF flours showed high starch and fiber contents, with low amylose levels. Flow Field-Flow Fractionation-MALS-dRI analysis revealed similar amylopectin molecular weights (MW = 1.04-1.15·108g/mol) and root mean square radius (rrms = 172-174 nm) in both BF flours, which were lower than those of banana flour (MW = 1.73·108 g/mol; rrms = 187 nm). Scanning electron micrographs revealed that BF starch granules were smaller (3-15 μm) and rougher compared to those found in the banana sample (15-50 μm). X-ray diffraction showed a B-type crystalline pattern in BF samples. Fourier-transform infrared spectroscopy showed a higher ordered crystallinity of starch and a significantly higher amount of disordered structures in the Amide I region in BF flours compared to banana. BF flours also exhibited higher gelatinization temperatures with a narrower range, indicating increased granular thermostability and amylopectin crystallite homogeneity. Peel flour contained high levels of polyphenols and minerals. The lower amylopectin molecular weight and size, smaller starch granules and lower amylose content of BF flours compared to banana flour could explain the higher starch-digestion-rate-index (SDRI) of their uncooked samples. Cooked BF flours, however, showed an SDRI 10 % lower than banana, suggesting a reduced glycemic index after gelatinization. This study provides valuable insights into BF flours composition, molecular and structural properties, and their relationship with digestibility. These findings are relevant for developing novel gluten-free foods. Further research is needed to assess the starch digestibility of real food products made with BF flours and to investigate their functional properties and technological performance.

Size exclusion chromatography and asymmetrical flow field-flow fractionation for structural characterization of polysaccharides: A comparative review

Natural polysaccharides exhibit a wide range of biological activities, which are closely related to their structural characteristics, including their molecular weight distribution, size, monosaccharide composition, glycosidic bond types and spatial conformation, etc. Size exclusion chromatography (SEC) and asymmetrical flow field-flow fractionation (AF4), as two potent separation techniques, both harbor potential for continuous development and enhancement. This manuscript reviewed the fundamental principles and separation applications of SEC and AF4. The structural information and spatial conformation of polysaccharides can be obtained using SEC or AF4 coupled with multiple detectors. In addition, this manuscript elaborates in detail on the shear degradation of samples such as polysaccharides separated by SEC. In addition, the abnormal elution that occurs during the application of the two methods is also discussed. Both SEC and AF4 possess considerable potential for ongoing development and refinement, thereby offering increased possibilities and opportunities for polysaccharide separation and characterization.

Valorization of Taioba Products and By-Products: Focusing on Starch

Unconventional food plants, popularized in Brazil as PANC, remain underutilized globally. In that sense, this study aims to explore the nutritional and functional properties of taioba (Xanthosoma sagittifolium), a plant with edible leaves and tubers, and to investigate its potential for industrial-scale application as a source of starch. A systematic review was carried out and meta-analysis following the PRISMA guidelines was conducted based on a random effects synthesis of multivariable-adjusted relative risks (RRs). The searches were carried out in seven search sources, among which were Web of Science, Elsevier's Science Direct, Wiley Online Library, Springer Nature, Taylor & Francis, Hindawi, Scielo, ACS-American Chemical Society, and Google Scholar. The systematic review was guided by a systematic review protocol based on the POT strategy (Population, Outcome, and Types of studies), adapted for use in this research. Mendeley was a resource used for organization, to manage references, and to exclude duplicates of studies selected for review. The findings revealed that taioba leaves are abundant in essential nutrients, proteins, vitamins, and minerals. Additionally, the tubers offer rich starch content along with vitamins and minerals like iron, potassium, and calcium, making them an ideal substitute for conventional sources on an industrial scale. This research highlights the significance of studying the functionalities, applicability, and integration of this PANC in our diets, while also emphasizing its capability as a substitute for traditional starch varieties. Moreover, exploiting this plant's potential adds value to Amazonian resources, reduces import costs, and diversifies resource utilization across multiple industrial sectors.

Flow field-flow fractionation coupled with multidetector: A robust approach for the separation and characterization of resistant starch

The unique properties of resistant starch (RS) have made it applicable in the formulation of a broad range of functional foods. The physicochemical properties of RS play a crucial role in its applications. Recently, flow field-flow fractionation (FlFFF) has attracted increasing interest in the separation and characterization of different categories of RS. In this review, an overview of the theory behind FlFFF is introduced, and the controllable factors, including FlFFF channel design, sample separation conditions, and the choice of detector, are discussed in detail. Furthermore, the applications of FlFFF for the separation and characterization of RS at both the granule and molecule levels are critically reviewed. The aim of this review is to equip readers with a fundamental understanding of the theoretical principle of FlFFF and to highlight the potential for expanding the application of RS through the valuable insights gained from FlFFF coupled with multidetector analysis.

Field-Flow Fractionation in Molecular Biology and Biotechnology

Field-flow fractionation (FFF) is a family of single-phase separative techniques exploited to gently separate and characterize nano- and microsystems in suspension. These techniques cover an extremely wide dynamic range and are able to separate analytes in an interval between a few nm to 100 µm size-wise (over 15 orders of magnitude mass-wise). They are flexible in terms of mobile phase and can separate the analytes in native conditions, preserving their original structures/properties as much as possible. Molecular biology is the branch of biology that studies the molecular basis of biological activity, while biotechnology deals with the technological applications of biology. The areas where biotechnologies are required include industrial, agri-food, environmental, and pharmaceutical. Many species of biological interest belong to the operational range of FFF techniques, and their application to the analysis of such samples has steadily grown in the last 30 years. This work aims to summarize the main features, milestones, and results provided by the application of FFF in the field of molecular biology and biotechnology, with a focus on the years from 2000 to 2022. After a theoretical background overview of FFF and its methodologies, the results are reported based on the nature of the samples analyzed.

Characterization of the molecular properties and allergenicity (IgE-binding capacity) of β-lactoglobulin by heat treatment using asymmetric-flow field-flow fractionation and ultra-performance liquid chromatography quadrupole time of flight mass chromatography

In this study, the heat product (90 °C, 10 min) of β-lactoglobulin (β-LG) was analyzed by asymmetric-flow field-flow fractionation (AF4) to observe the effect of heat treatment. The changes in molar mass (M) and molar size induced by heat treatment were characterized by AF4, and changes in molar shape were observed by transmission electron microscopy (TEM). The results showed that β-LG dissociated and aggregated into four fractions with different M values, sizes, and shapes after heat treatment. The vast aggregations with the highest allergenicity (IgE-binding capacity) might enhance the allergenicity of β-LG. However, the number of characterized epitope peptides was decreased due to heat treatment. The above results provide some references for related studies of β-LG and its allergenicity. Further separation and characterization of the high-allergenicity fractions and peptides will help to eliminate allergens in dairy products and reduce the occurrence of allergic reactions.

Insights into the structure and conformation of potato resistant starch (type 2) using asymmetrical flow field-flow fractionation coupled with multiple detectors

Insight into the structure and conformation characteristics of starch that influence its enzyme susceptibility is import for its potential application. In this study, the capacity of asymmetrical flow field-flow fractionation (AF4) coupled online with multi-angle light scatting (MALS) and differential refractive index (dRI) detectors (AF4-MALS-dRI) for monitoring of change in structure and conformation of potato starch during enzymatic hydrolysis was evaluated. The dissolution behavior of potato resistant starch (type 2) (PRS) was investigated. The effect of incubation time and amyloglucosidase concentration on the structure and conformation of potato starch was studied. The apparent density and the ratio of R_g (radius of gyration) to R_h (hydrodynamic radius) obtained from AF4-MALS-dRI were proven to be important parameters as they offer an insight into conformation of PRS at molecular level. Results suggested that gelatinization process made potato amylose molecules have a loose and random coil conformation which could contribute to an acceleration of enzymatic hydrolysis of potato starch. Furthermore, an intermediate with an elongated branched conformation was found between amylose and amylopectin populations, which may play a role in digestion property of potato starch. The results demonstrated that AF4-MALS-dRI is a powerful tool for better understanding of conformation of PRS.

Perspectives on protein biopolymers: miniaturized flow field-flow fractionation-assisted characterization of a single-cysteine mutated phaseolin expressed in transplastomic tobacco plants

The development of plant-based protein polymers to employ in biofilm production represents the promising intersection between material science and sustainability, and allows to obtain biodegradable materials that also possess excellent physicochemical properties. A possible candidate for protein biopolymer production is phaseolin, a storage protein highly abundant in P Vulgaris beans. We previously showed that transformed tobacco chloroplasts could be employed to express a mutated phaseolin carrying a signal peptide (directing it into the thylakoids) also enriched of a cysteine residue added to its C-terminal region. This modification allows for the formation of inter-chain disulfide bonds, as we previously demonstrated, and should promote polymerization. To verify the effect of the peptide modification and to quantify polymer formation, we employed hollow-fiber flow field-flow fractionation coupled to UV and multi-angle laser scattering detection (HF5-UV-MALS): HF5 allows for the selective size-based separation of phaseolin species, whereas MALS calculates molar mass and conformation state of each population. With the use of two different HF5 separation methods we first observed the native state of P.Vulgaris phaseolin, mainly assembled into trimers, and compared it to mutated phaseolin (P*) which instead resulted highly aggregated. Then we further characterized P* using a second separation method, discriminating between two and distinct high-molecular weight (HMW) species, one averaging 0.8 × 106 Da and the second reaching the tens of million Da. Insight on the conformation of these HMW species was offered from their conformation plots, which confirmed the positive impact of the Cys modification on polymerization.

Applications of asymmetrical flow field-flow fractionation for separation and characterization of polysaccharides: A review

Polysaccharides are the most abundant natural biopolymers on the earth and are widely used in food, medicine, materials, cosmetics, and other fields. The physicochemical properties of polysaccharides such as particle size and molecular weight often affect their practical applications. In recent years, asymmetrical flow field-flow fractionation (AF4) has been widely used in the separation and characterization of polysaccharides because it has no stationary phases or packing materials, which reduces the risk of shear degradation of polysaccharides. In this review, the principle of AF4 was introduced briefly. The operation conditions of AF4 for the analysis of polysaccharides were discussed. The applications of AF4 for the separation and characterization of polysaccharides from different sources (plants, animals, and microorganisms) over the last decade were critically reviewed.