Characterization of young bamboo culm starch from Dendrocalamus asper

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.

Young bamboo flour as a substitute for emulsifying salts in requeijão cremoso processed cheese and the effect on the quality parameters

The effect of the substitution of emulsifying salt by the young bamboo flour (BF) (0, 25, 50, 75, 100 % w/w) on requeijão cremoso processed cheese [REQ, REQ 25, REQ 75 REQ 100]) processing was investigated. Gross composition, calcium and sodium values, functional properties (melting rate), color parameters (L, a*, b*, C*, and Whiteness Index, WI), texture profile, fatty acid profile, volatile organic compounds (VOCs), and sensory profiling were evaluated. No effect was observed on the gross composition; however, sodium and melting rate values were decreased, and calcium values presented the opposite behavior. BF could modify the optical parameters, observing an increase in WI values. Higher BF addition increased hardness and lowered elasticity, and regarding the fatty acid profile, there is no significant difference. Different volatile compounds were noted in a proportional form with the BF addition, which was reflected in similar sensory acceptance for REQ 25 and control samples. Although some aspects require further in-depth studies, using BF as a substitute for emulsifying salt in requeijão cremoso processed cheese appears to be a viable option, especially when considering partial replacements.

Differential Studies on the Structure of Lignin-Carbohydrate Complexes (LCC) in Alkali-Extracted Plant Hemicelluloses

Hemicellulose extracted by alkali treatment is of interest because of the advantages of its intact sugar structure and high degree of polymerization. However, the hemicellulose extracted by alkali treatment contained more lignin fragments and the presence of a lignin-carbohydrate complex (LCC), which affected the isolation and purification of hemicellulose and its comprehensive utilization. Therefore, the evaluation of the LCC structure of different types of lignocellulosic resources is of great significance. In this study, the LCC structures of hardwoods and Gramineae were enriched in alkaline systems. Information on the composition, structural proportions, and connection patterns of LCC samples was discussed. The similarities and differences between the LCC structures of different units of raw materials were comparatively studied. The results indicated that the monosaccharide fractions were higher in the LCC of Gramineae compared to hardwoods. The composition of the lignin fraction was dominated by G and S units. The phenyl glycosidic (PhGlc) bond is the predominant LCC linkage under alkali-stabilized conditions. In addition, Gramineae PhGlc types are more numerous compared to hardwoods. The results of the study provide insights into the differences in the chemical composition and structural features of LCC in different plants and provide important guidance for the optimization of the process of purifying hemicellulose.

Unveiling the Dissolution Regularities of the Lignin-Carbohydrate Complex in Bamboo Cell Walls during Alkali Pretreatment

Bamboo is a promising biomass resource. However, the complex multilayered structure and chemical composition of bamboo cell walls create a unique anti-depolymerization barrier, which increases the difficulty of separation and utilization of bamboo. In this study, the relationship between the connections of lignin-carbohydrate complexes (LCCs) within bamboo cell walls and their multilayered structural compositions was investigated. The chemical composition, structural properties, dissolution processes, and migration mechanisms of LCCs were analyzed. Alkali-stabilized LCC bonds were found to be predominantly characterized by phenyl glycoside (PhGlc) bonds along with numerous p-coumaric acid (PCA) linkage structures. As demonstrated by the NMR and CLSM results, the dissolution of the LCC during the alkaline pretreatment process was observed to migrate from the inner secondary wall (S-layer) of the bamboo fiber cell walls to the cell corner middle lamella (CCML) and compound middle lamella (CML), ultimately leading to its release from the bamboo. Furthermore, the presence of H-type lignin-FA-arabinoxylan linkage structures within the bamboo LCC was identified with their primary dissolution observed in the S-layer of the bamboo fiber cell walls. The study results provided a clear target for breaking down the anti-depolymerization barrier in bamboo, signifying a major advancement in achieving the comprehensive separation of bamboo components.

A Simple and Effective Method to Enhance the Mechanical Properties, Dimensional Stability, and Mildew Resistance of Bamboo Scrimber

Given the increasingly prominent contradiction between the supply of and demand for wood, the abundant resource of bamboo can be a good substitute. Bamboo scrimber can effectively improve the utilization rate of bamboo and has good mechanical properties. However, bamboo scrimber has the problem of poor mildew resistance, and does not meet the requirements for outdoor applications. In this study, in order to further improve the mildew resistance and mechanical properties of bamboo scrimber, alkali treatment was used to remove some nutrients from the bamboo bundles and change the pH of the bamboo scrimber. The results showed that nutrients such as hemicellulose, lignin, starch, and sugar were notably removed from bamboo bundles, and the pH of bamboo was slightly alkaline. The anti-mildew effect was significantly enhanced, which could allow use in outdoor environments, and the mechanical properties and dimensional stability were also improved. Among them, TB6 bamboo scrimber showed comprehensively excellent properties. The infection time in the laboratory mildew test increased from 3 days to more than 30 days, and the infection time in the outdoor mildew resistance test increased from 1 week to more than 8 weeks; the static bending intensity of TB6 increased by 62.6% to 150 MPa, and the bending modulus increased by 71.7% to 14.2 GPa; the change rate of water absorption thickness was reduced to 0.58%. This modification method effectively improved the mildew resistance of bamboo scrimber, while maintaining high mechanical strength, and provides a new method for the outdoor application of bamboo scrimber.

Chachafruto starch: Physicochemical characterization, film-forming properties, and 3D printability

This work aimed to characterize the physicochemical, film-forming properties, and 3D printability of a nonconventional starch from chachafruto. The chachafruto native starch (CHS) presented an excellent extraction yield (10 % db) and purity (99 % db), along with an oval and round morphology, a smooth surface with few defects, and a mean diameter of 15.4 μm. The typical B-type diffraction pattern was observed in the CHS with a crystallinity of 17.4 %. The starch presented a paste temperature of 66.1 °C, an enthalpy of 11.5 J g-1, and a final viscosity of 596 Brabender Units. The thermal analysis demonstrated good thermal stability. The evaluated film presented a reduction in crystallinity (8.18 %) to the CHS, which generated a good elasticity in the material. Likewise, it presented a continuous structure without cracks, providing good barrier properties (2.3 × 10-9 g∙m-1∙s-1∙Pa-1) and high transparency. Meanwhile, 3D prints prepared with CHS showed good textural properties and high consistency. The morphological analysis showed that the prints generated organized cell structures. However, high concentrations of CHS were not efficient in obtaining 3D prints. The results of this work demonstrate the tremendous industrial potential of chachafruto as an unconventional source of starch and some alternative uses for adding value to the crop.

Optimization of starch extraction from Amorphophallus paeoniifolius corms using response surface methodology (RSM) and artificial neural network (ANN) for improving yield with tenable chemical attributes

The development of the extraction process for improving the starch yield from unconventional plants is emerging as a topic of interest. In this respect, the present work aimed to optimize the starch extraction from the corms of elephant foot yam (Amorphophallus paeoniifolius) with the help of response surface methodology (RSM) and artificial neural network (ANN). The RSM model performed better than the ANN in predicting the starch yield with higher precision. In this connection, this study for the first time reports the significant improvement of starch yield from A. paeoniifolius (51.76 g/100 g of the corm dry weight). The extracted starch samples based on yield - high (APHS), medium (APMS), and low (APLS) exhibited a variable granule size (7.17-14.14 μm) along with low ash content, moisture content, protein, and free amino acid indicating purity and desirability. The FTIR analysis also confirmed the chemical composition and purity of the starch samples. Moreover, the XRD analysis showed the prevalence of C-type starch (2θ = 14.303°). Based on other physicochemical, biochemical, functional, and pasting properties, the three starch samples showed more or less similar characteristics thereby indicating the sustentation of beneficial attributes of starch molecules irrespective of the variation in extraction parameters.

Technological and prebiotic aspects of young bamboo culm flour (Dendrocalamus latiflorus) combined with rice flour to produce healthy extruded products

Young bamboo culm flour (YBCF) has proved to be a healthy and sustainable ingredient, due to its high fiber content and high yield of bamboo crops. The present study evaluated the effects of YBCF from Dendrocalamus latiflorus on the physicochemical, technological properties and prebiotic activity of rice-based extrudates aiming to expand its application. The extrudates were produced in a twin-screw extruder with different RF:YBCF concentrations (100:0; 95:5, 90:10, and 85:15 %). During the process, the specific mechanical energy increased as YBCF content increased because of the high shear favored by YBCF particles. With increasing RF replacement by YBCF, the extruded products presented a significant (p < 0.05, by the Scott-Knott test) increase in hardness (57.37 to 82.01 N) and water solubility index (12.80 to 34.10 %), as well as a decrease in color luminosity (L*=85.49 to 82.83), expansion index (2.68 to 1.99), and pasting properties. In addition, all extrudate samples presented bifidogenic activity. Therefore, YBCF exhibited attractive technological properties and can be used as an ingredient in the production of healthy and sustainable extruded products.

Non-conventional starch from cubio tuber (Tropaeolum tuberosum): Physicochemical, structural, morphological, thermal characterization and the evaluation of its potential as a packaging material

This work aimed to characterize the physicochemical, structural, morphological, and thermal properties of a non-conventional starch obtained from cubio (Tropaeolum tuberosum), as well as to evaluate the potential use of this native Andean tuber in the preparation of biodegradable packaging. The cubio starch (CUS) showed an intermediated apparent amylose content (31.2 %) accompanied by a high CIE whiteness index (90.8). About the morphology and particle size, the CUS exhibited irregular oval and round shapes and a smooth surface with a mean particle diameter of 14.04 ± 0.1 μm. Although it showed good stability regarding pasting properties, the final viscosity was low. Native CUS exhibits a typical B-type diffraction structure, with a relative crystallinity of 16 %. The resistant starch (RS) fraction of the CUS was 94 %, indicating a low susceptibility to enzymatic hydrolysis. The thermal analysis demonstrated that the CUS showed good thermal stability. Additionally, the films prepared using CUS as raw material showed continuous surfaces without porosities, good thermal stability, and high transparency. The results of this work demonstrate the industrial potential of the CUS as it presents characteristics comparable to commercial potato starch.

Association among starch storage, metabolism, related genes and growth of Moso bamboo (Phyllostachys heterocycla) shoots

BACKGROUND

Both underground rhizomes/buds and above-ground Moso bamboo (Phyllostachys heterocycla) shoots/culms/branches are connected together into a close inter-connecting system in which nutrients are transported and shared among each organ. However, the starch storage and utilization mechanisms during bamboo shoot growth remain unclear. This study aimed to reveal in which organs starch was stored, how carbohydrates were transformed among each organ, and how the expression of key genes was regulated during bamboo shoot growth and developmental stages which should lay a foundation for developing new theoretical techniques for bamboo cultivation.

RESULTS

Based on changes of the NSC content, starch metabolism-related enzyme activity and gene expression from S0 to S3, we observed that starch grains were mainly elliptical in shape and proliferated through budding and constriction. Content of both soluble sugar and starch in bamboo shoot peaked at S0, in which the former decreased gradually, and the latter initially decreased and then increased as shoots grew. Starch synthesis-related enzymes (AGPase, GBSS and SBE) and starch hydrolase (α-amylase and β-amylase) activities exhibited the same dynamic change patterns as those of the starch content. From S0 to S3, the activity of starch synthesis-related enzyme and starch amylase in bamboo rhizome was significantly higher than that in bamboo shoot, while the NSC content in rhizomes was obviously lower than that in bamboo shoots. It was revealed by the comparative transcriptome analysis that the expression of starch synthesis-related enzyme-encoding genes were increased at S0, but reduced thereafter, with almost the same dynamic change tendency as the starch content and metabolism-related enzymes, especially during S0 and S1. It was revealed by the gene interaction analysis that AGPase and SBE were core genes for the starch and sucrose metabolism pathway.

CONCLUSIONS

Bamboo shoots were the main organ in which starch was stored, while bamboo rhizome should be mainly functioned as a carbohydrate transportation channel and the second carbohydrate sink. Starch metabolism-related genes were expressed at the transcriptional level during underground growth, but at the post-transcriptional level during above-ground growth. It may be possible to enhance edible bamboo shoot quality for an alternative starch source through genetic engineering.

Young culm of Dendrocalamus asper, Bambusa tuldoides and B. Vulgaris as source of hemicellulosic dietary fibers for the food industry

Bamboo is a grass that has gained economic attention in the food industry as a source of dietary fiber, and the young bamboo culm may be an alternative to supply fibers to the market. The objective was to evaluate and characterize different portions (bottom, middle and top) of the young bamboo culm fibrous fractions from Dendrocalamus asper, Bambusa tuldoides and B. vulgaris regarding their color parameters, physicochemical composition and hemicellulosic polysaccharide characterization. Fibrous fractions were obtained after starch extraction and results showed high amounts of total dietary fiber (79-89%). The hemicellulosic polysaccharide contents (35.4-41.5%) demonstrated great potential for commercial extraction and so, we extracted them with alkali and fractionated regarding their solubility in cold-water. Insoluble polysaccharides (KP fractions) were obtained in higher yields (from 21.2% to 38.5%) than the soluble ones (KS fractions, yields from 2.3% to 5.2%). Monosaccharide composition showed mainly xylose and arabinose, with some minor amounts of mannose and galactose in some fractions. In a detailed NMR analysis, the presence of neutral xylans and arabinoxylans could be observed in all studied bamboo species, which can be used in food products and also in the production of xylooligosaccharides (XOS), biomaterials and biofuels.