Exploring the remarkable effects of microwave treatment on starch modification: From structural evolution to changed physicochemical and digestive properties.

As one of the crucial components of the food system, starch can be hydrolyzed into glucose after gastrointestinal digestion, so regulating its digestive properties is vital for maintaining health. Microwaves can promote the rearrangement of intramolecular structure of starch, thus improving its physicochemical properties, enhancing its slowly digestible features, and expanding its scope of application. This review zooms in describing recent research results concerning the effects of microwave treatment on the multi-scale structure and physicochemical properties of starch and summarizing the patterns of these changes. Furthermore, the changes in starch structure, resistant starch content, and glycemic index after digestion are pointed out to gain an insight into the enhancement of starch slowly digestible properties by microwave treatment. The resistance of starch to enzymatic digestion may largely hinge on the specific structures formed during microwave treatment. The multi-level structural evolutions of starch during digestion endow it with the power to resist digestion and lower the glycemic index. The properties of starch dictate its application, and these properties are highly associated with its structure. Consequently, understanding the structural changes of microwave-modified starch helps to prepare modified starch with diversified varieties and functional composites.

Investigation of the link between first-order kinetic models of the in vitro digestion of native starches and the accompanying changes in their crystallinity and structure.

Starch is the main source of dietary energy for humans. In order to understand the mechanisms governing native starch in vitro digestion, digestion data for six starches [wheat, maize, (waxy) maize, rice, potato and pea] of different botanical sources were fitted with the most common first-order kinetic models, i.e. the single, sequential, parallel and combined models. Parallel and combined models provided the most accurate fits and showed that all starches studied except potato starch followed a biphasic in vitro digestion pattern. The biological relevance of the kinetic parameters was explored by determining changes in crystallinity and molecular structure of the undigested starch residues during in vitro digestion. While the crystallinity of the undigested potato starch residues did not change substantially, a respectively small and large decrease in their amylose content and chain length during in vitro digestion was observed, indicating that amylose was digested slightly preferentially over amylopectin in native starch. However, the molecular structure of the starch residues changed too slowly and/or only to an insufficient extent to relate it to the kinetic parameters of the digested fractions predicted by the models. Such parameters thus need to be interpreted with caution, as their biological relevance still needs to be proven.

Deuteration of non-labile protium in starch: Biosynthesis and characterisation from yeast-derived starch granules.

Deuterium labelling of the non-labile protium atoms in starch granules has been achieved for the first time, by growing genetically modified yeast on deuterated media. Mass spectrometry of the glucose monomers from digested starch showed 44 % average deuteration of the non-labile protium when grown on partially deuterated raffinose (with average deuteration 48 %); yielding starch with 26 % average overall deuteration. Non-labile deuteration was also demonstrated using D2O solvent in the culture medium. Solid-state NMR revealed that deuteration was not evenly distributed across the monomer, being highest at the C6 carbon and lowest at the C1 carbon. SANS revealed two structural features at q = 0.05 Å-1 and 0.4 Å-1, the first corresponding to a lamellar repeat of approximately 12-13 nm while the latter is consistent with B-type crystalline polymer packing. Furthermore, solvent contrast variation SANS analysis yielded a contrast match point of 66 mol% D2O indicative of approximately 30-35 % average deuteration of the bulk granules, consistent with mass spectroscopy. When coupled with the more traditional process of exchange of labile protium in the hydroxyl groups by D2O solvent exchange, the biosynthesis of highly deuterated starch opens new opportunities for neutron scattering experiments involving multicomponent starch-based systems.

Co-encapsulation of hydrophilic and hydrophobic bioactives stabilized in nanostarch-assisted emulsion for inner core gel of coaxial 3D printing.

3D printing technology, especially coaxial 3D mode of multiple-component shaping, has great potential in the manufacture of personalized nutritional foods. However, integrating and stabilizing functional objectives of different natures remains a challenge for 3D customized foods. Here, we used starch nanoparticle (SNP) to assisted soy protein (SPI) emulsion to load hydrophilic and hydrophobic bioactives (anthocyanin, AC, and curcumin, Cur). The addition of SNP significantly improved the storage stability of the emulsion. Xanthan gum (XG) was also added to the SNP/SPI system to enhance its rheology and form an emulsion gel as inner core of coaxial 3D printing. Low field nuclear magnetic resonance and emulsification analyses showed that AC/Cur@SNP/SPI/XG functional inner core had a strong water binding state and good stability. After printing with outer layer, the SNP/SPI coaxial sample had the lowest deviation rate of 0.8 %. Also, SNP/SPI coaxial sample showed higher AC (90.2 %) and Cur (90.8 %) retention compared to pure starch (S), pure SNP, pure SPI, and S/SPI samples as well as SNP/SPI sample printed without outer layer. In summary, this study provides a new perspective for the manufacture of customized products as multifunctional foods, feeds and even potential delivery of drugs.

The galactomannan-EGCG physical complex: Effect of branching degree and molecular weight on structural and physiological properties.

Polysaccharides and polyphenols are bioactive components that co-exist in many plant foods. Their binary interaction in terms of the structure-function relationships, however, has not been well clarified. This study elucidated the correlation between the structural and physiological properties of galactomannan (GM) -catechin monomer complexes and GM with different branching or molecular weight (Mw). Results indicated that locus bean gum with lower branching degree (Gal/Man is 0.259) bound more readily to EGCG with adsorption rate of 19.42 %. EGCG and ECG containing galloyl groups were more inclined to form hydrogen bonds with GMs, significantly improving the adsorption by GMs. The introduction of EGCG could enhance the antioxidant activity and starch digestion inhibition of GM, which positively correlated with the adsorption capacity of EGCG. The guar gum (GG) with higher Mw (7384.3 kDa) could transport 71.51 % EGCG into the colon, while the retention rate of EGCG reaching the colon alone was only 46.33 %. Conversely, GM-EGCG complex with lower Mw (6.9 kDa) could be readily utilized by gut microbiota, and increased production of short-chain fatty acids (SCFAs). This study elucidated the structure-properties relationship of GM-EGCG complexes, and provide a new idea for the development and precision nutrition of polysaccharides-polyphenol complexes fortified functional foods.

Octenylsuccinylation strategy to construct high-amylose maize starch-myristic acid complexes with high thermal stability, complexation efficiency and anti-retrogradation ability.

Gelatinizing high-amylose maize starch (HAMSt) requires high temperatures to allow complexation with lipids, making it a challenging process. An octenylsuccinylation method was examined as a part of a strategy to decrease the gelatinization temperature of HAMSt, thereby promoting the complexation between HAMSt and myristic acid (MAc). Octenyl succinic anhydride (OSA) modification of HAMSt reduces the onset gelatinization temperature of HAMSt from 71.63 °C to 66.97 °C. Moreover, as the OSA concentration increased from 2 % to 11 %, the degree of substitution and molecular weights of the esterified HAMSt gradually increased from 0.0069 to 0.0184 and from 0.97 × 106 to 1.17 × 106 g/mol, respectively. Fourier transform infrared analysis indicated that the octenyl-succinate groups were grafted onto the HAMSt chains. The formation of HAMSt-MAc complexes improved the thermal stability of OSA-treated HAMSt (peak temperature increased by 0.11 °C-13.95 °C). Moreover, the diffraction intensity of the V-type peak of the 11 % sample was greater than that of other samples. Finally, the anti-retrogradation ability was in the order of OSA-HAMSt-MAc complexes > HAMSt-MAc complexes > HAMSt. Overall, our results indicate that octenylsuccinylation can be an effective strategy to promote the formation of OSA-HAMSt-MAc complexes and delay starch retrogradation.

Isolated cassava cells: Comparison of structure and physicochemical properties with starch and whole flour.

Individual cells are the smallest units of the plant tissue structure, and their structure and physicochemical properties are essential for whole food processing. In this study, cassava cells were isolated using acid-alkali, hydrothermal, and pectinase methods, and the differences in microstructure and physicochemical properties among the cells, starch, and whole flour were investigated. Cassava cells isolated using pectinase showed intact individual cells with a higher isolation rate and less damage to the cell wall structure and intracellular composition. The presence of cell walls in intact individual cells inhibited the swelling and leaching of starch, resulting in a lower peak viscosity and higher gelatinization temperature than those of starch. The intact cell structure and non-starch composition enhanced the shear resistance of the gels in the sample. Heat treatment led to the gelatinization of intracellular starch and increased the permeability of the cell wall, destroying the physical barrier function of the cell wall; however, the compact cell matrix and non-starch components can inhibit starch hydrolysis. This study suggests that cells isolated using pectinase can be used to investigate the effect of cell walls on the functional properties of intracellular starch in cassava. The isolated cells provide new insights into the cassava industry.

Effects of biodegradation of starch-nanocellulose films incorporated with black tea extract on soil quality.

This study aimed to investigate the biodegradation behaviour of starch/nanocellulose/black tea extract (SNBTE) films in a 30-day soil burial test. The SNBTE films were prepared by mixing commercial starch, nanocellulose (2, 4, and 6%), and an aqueous solution of black tea extract by a simple mixing and casting process. The chemical and morphological properties of the SNBTE films before and after biodegradation were characterized using the following analytical techniques such as field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), and fourier transform infrared (FTIR). The changes in soil composition, namely pH, electrical conductivity (EC), moisture content, water holding capacity (WHC), soil respiration, total nitrogen, weight mean diameter (MDW), and geometric mean diameter (GMD), as a result of the biodegradation process, were also estimated. The results showed that the films exhibited considerable biodegradability (35-67%) within 30 days while increasing soil nutrients. The addition of black tea extract reduced the biodegradation rate due to its polyphenol content, which likely resulted in a reduction in microbial activity. The addition of nanocellulose (2-6% weight of starch) increased the tensile strength, but decreased the elongation at break of the films. These results suggest that starch nanocellulose and SNBTE films are not only biodegradable under soil conditions but also positively contribute to soil health, highlighting their potential as an environmentally friendly alternative to traditional plastic films in the packaging industry.

Changes in overall digital structure, starch properties and moisture distribution reveal how the hardness of wheat noodles evolves under different cooking status.

To elucidate the relationship between the structural evolution of starch within noodles during cooking and the hardness, the panoramic and local microstructure of cooked noodles were quantitatively analyzed, and the structure of starch in noodles were measured. We found that in the case of starch within cooked noodles with a high degree of swelling, the quantitative analysis of each ring was sufficient to represent the structural differences. Changes occurring in starch inside noodles during cooking were not homogeneous. The structural modifications of starch in the outer ring were greater than in the inner ring along with the extension of cooking time. The main reason responsible for the high hardness was attributed to low swelling degree and high short-range order of starch in the center. Water migration from the periphery to the center of the noodles, which was closely related to the fine structure of amylopectin, determined the state of central starch. Wheat starch with more large amylopectin molecules and more long amylopectin chains could enhance the inhibition of water migration and decrease the swelling degree of starch in the center, in order to endow a high hardness to noodles. These results will be useful for the ingredients selection for the production of noodles with desirable quality. In addition, the analysis method established in this work promoted the realization of quantitative comparison of the cooked noodles microstructure, that is an effective tool to clarify the structural basis of macroscopic quality of noodles.

Impact of ultrasound process on cassava starch nanoparticles and Pickering emulsions stability.

Using green techniques to convert native starches into nanoparticles is an interesting approach to producing stabilizers for Pickering emulsions, aiming at highly stable emulsions in clean label products. Nanoprecipitation was used to prepare the Pickering starch nanoparticles, while ultrasound technique has been used to modulate the size of these nanoparticles at the same time as the emulsion was developed. Thus, the main objective of this study was to evaluate the stabilizing effect of cassava starch nanoparticles (SNP) produced by the nanoprecipitation technique combined with ultrasound treatment carried out in the presence of water and oil (more hydrophobic physicochemical environment), different from previous studies that carry out the mechanical treatment only in the presence of water. The results showed that the increased ultrasound energy input could reduce particle size (117.58 to 55.75 nm) and polydispersity (0.958 to 0.547) in aqueous dispersions. Subsequently, Pickering emulsions stabilized by SNPs showed that increasing emulsification (ultrasonication) time led to smaller droplet sizes and monomodal size distribution. Despite flocculation, long-term ultrasonication (6 and 9 min) caused little variation in the droplet size after 7 days of storage. The cavitation effects favored the interaction between oil droplets through weak attraction forces and particle sharing, favoring the Pickering stabilization against droplet coalescence. Our results show the potential to use only physical modifications to obtain nanoparticles that can produce coalescence-stable emulsions that are environmentally friendly.

Investigation of oligosaccharides and allulose as sucrose replacers in low-moisture wire-cut cookies.

Non-digestible oligosaccharides (OS) and allulose have beneficial health properties and could reduce the amount of added sugar in baked goods. In this study allulose and various OS [fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), lactosucrose (LOS), isomalto-oligosaccharides (IMO), Promitor 70R (P70R), and xylo-oligosaccharides (XOS)] were added to a wire-cut cookie formulation at concentrations determined to have similar effects on the gelatinization temperature (Tgel) of starch relative to sucrose. Different baking performance attributes of the doughs and cookies were assessed, including: appearance, spread, color, texture, and % moisture loss after baking. The results were correlated to: OS solution and solid properties and OS effects on starch thermal events (gelatinization, pasting, and retrogradation). The Tgel-matching formulation protocol was effective in producing reduced-sugar cookies which had similar appearance, color, and spread attributes compared to the sucrose control; however, cookie texture significantly varied. Cookies containing allulose were the least similar to the control, having darker color, reduced spread, and softer cake-like texture. The only OS cookies that matched the texture of the sucrose control contained LOS, while P70R cookies were the hardest. Cookie texture correlated strongly with the % total moisture loss after baking (r = -0.8763) and was best explained by OS solution viscosity: more viscous OS solutions limited moisture release and resulted in harder cookies. The Tgel of starch also correlated with OS solution viscosity (r = 0.7861) and should be accounted for in reduced sugar applications. The OS recommended as sucrose replacers in cookies based on principal component analysis groupings were: XOS > IMO > LOS > and GOS.

High-efficiency conversion of corn bran to ethanol at 150 L scale.

Fractionated corn bran was processed to maximize ethanol production from starch, cellulose, and xylan. After various bench-scale experiments, an optimized process with dilute acid pretreatment (1.5 % w/w H2SO4) at 90 °C for 60 min was utilized followed by enzymatic hydrolysis using cellulase and hemicellulase for 48 hr. After simultaneous saccharification (regarding starch) and fermentation at 150 L using an engineered yeast, which consumes both glucose and xylose to make ethanol, the 86 % total sugar conversion yield was achieved, including conversions of 95 % for starch, 77 % for cellulose and 77 % for xylan. Also, an accurate mass balance was formulated for ethanol-producing carbohydrates including starch, cellulose, and xylan from feedstock to final ethanol. A highly efficient process of converting corn fiber to ethanol was successfully scaled up to 150 L.

Fabrication of bio-inspired carbon nanodot-corn starch nanocomposite films via extrusion process for sustainable active food packaging applications.

In this study, carbon nanodot (CD)-corn starch (CS) nanocomposite films are fabricated for active food packaging applications. First, ginkgo biloba leaves (GBL) were used as a biomass-derived carbon precursor, and a facile hydrothermal method was employed to synthesise environmentally sustainable CDs. The GBL-derived carbon nanodots (gCDs) were then characterised and incorporated into a CS matrix via an extrusion process to fabricate the CS/gCD nanocomposite film. The effects of various gCD concentrations on the physicochemical and functional properties of CS/gCD composite films were systematically investigated. The gCD exhibited non-cytotoxic effect against human colorectal adenocarcinoma cell line (Caco-2) cells when exposed up to 1000 µg/mL. The incorporation of gCDs into the CS film improved its mechanical properties, with the toughness of the CS/gCD2% nanocomposite film exhibiting 198 % superiority compared to the CS film. In addition, the oxygen barrier and UV-blocking properties were significantly improved. Furthermore, the CS/gCD nanocomposite film significantly extended the shelf life of ω-3 oils owing to the superior antioxidant activity of the gCDs, exhibiting only 9 meq/kg during the 15-day storage period. Our results suggest that the developed CS/gCD active composite film is a promising candidate for environmentally sustainable solutions to enhance food shelf life and reduce food waste.

Multiscale modeling of solid starch-based foods digestion in the intestinal tract for dietary property-based glycemic prediction.

The digestion of starch-based foods in the intestinal tract is important for human health. Modeling the details enhances fundamental understanding and glycemic prediction accuracy. It is, however, a challenge to take granular properties into account. A multiscale digestion model has been proposed to characterize mass transfer and hydrolysis reaction at both the intestine and particle scales, seamlessly integrating inter-scale mass exchange. A specific grid scheme was formulated for the shrinkage and transport of the particle computational domain. By incorporating additional glycemic-related processes, e.g., intestinal absorption, a dietary property-based glycemic prediction system has been developed. Its effectiveness was validated based on a human tolerance experiment of cooked rice particles. The model-based investigation comprehensively reveals the impact of initial size on digestion behavior, specifically in terms of enzyme distribution and particle evolution. This work also demonstrates the significance of modeling both particle-scale diffusion and intestine-scale transport, a combination not previously explored. The results indicate that ignoring the former mechanism leads to an overestimation of the glycemic peak by at least 50.8%, while ignoring the latter results in an underestimation of 16.3%.

Influence of Lithium Triflate Salt Concentration on Structural, Thermal, Electrochemical, and Ionic Conductivity Properties of Cassava Starch Solid Biopolymer Electrolytes.

Cassava starch solid biopolymer electrolyte (SBPE) films were prepared by a thermochemical method with different concentrations of lithium triflate (LiTFT) as a dopant salt. The process began with dispersing cassava starch in water, followed by heating to facilitate gelatinization; subsequently, plasticizers and LiTFT were added at differing concentrations. The infrared spectroscopy analysis (FTIR-ATR) showed variations in the wavenumber of some characteristic bands of starch, thus evidencing the interaction between the LiTFT salt and biopolymeric matrix. The short-range crystallinity index, determined by the ratio of COH to COC bands, exhibited the highest crystallinity in the salt-free SBPEs and the lowest in the SBPEs with a concentration ratio (Xm) of 0.17. The thermogravimetric analysis demonstrated that the salt addition increased the dehydration process temperature by 5 °C. Additionally, the thermal decomposition processes were shown at lower temperatures after the addition of the LiTFT salt into the SBPEs. The differential scanning calorimetry showed that the addition of the salt affected the endothermic process related to the degradation of the packing of the starch molecules, which occurred at 70 °C in the salt-free SBPEs and at lower temperatures (2 or 3 °C less) in the films that contained the LiTFT salt at different concentrations. The cyclic voltammetry analysis of the SBPE films identified the redox processes of the glucose units in all the samples, with observed differences in peak potentials (Ep) and peak currents (Ip) across various salt concentrations. Electrochemical impedance spectroscopy was used to establish the equivalent circuit model Rf-(Cdl/(Rct-(CPE/Rre))) and determine the electrochemical parameters, revealing a higher conduction value of 2.72 × 10-3 S cm-1 for the SBPEs with Xm = 17 and a lower conduction of 5.80 × 10-4 S cm-1 in the salt-free SBPEs. It was concluded that the concentration of LiTFT salt in the cassava starch SBPE films influences their morphology and slightly reduces their thermal stability. Furthermore, the electrochemical behavior is affected in terms of variations in the redox potentials of the glucose units of the biopolymer and in their ionic conductivity.

Investigating extrusion impact on functional, textural properties, morphological structure, and molecular interactions in hulless barley-based extruded snacks supplemented with mung bean.

The effect of varying extrusion conditions on the functional properties of hulless barley-mung bean (70:30) extruded snacks was investigated using response surface methodology with feed moisture (FM), barrel temperature (BT), and screw speed (SS) as process variables. Results revealed significant impacts on functional characteristics with varying extrusion conditions. Bulk density (BD) of extruded snacks ranged from 0.24 to 0.42 g/cm3, showing that lower FM and higher BT results in lower BD while it increased with increasing FM, SS, and BT. The expansion ratio (ER) of extruded snacks ranged between 2.03 and 2.33, showing BT and SS had a desirable positive effect, whereas increasing FM led to decreased ER. Increasing BT and SS depicted a negative effect on water absorption index, whereas FM showed positive effect, which ranged between 4.21 and 4.82 g/g. A positive effect on water solubility index was depicted by BT and SS, which ranges between 9.01% and 13.45%, as higher SS and BT led to starch degradation and increased solubility suggesting better digestibility. The hardness of extruded snacks ranged from 32.56 to 66.88 Newton (N), showing increasing FM increased hardness, whereas higher SS and BT resulted in lowering the hardness. Scanning electronic microscope (SEM) analysis revealed structural changes in extrudates in comparison with nonextruded flour, indicating starch gelatinization and pore formation affected by varying processing parameters. Shifts in absorption bands were observed in Fourier transform infrared spectroscopy (FT-IR), suggesting structural changes in starch and protein. Understanding the effects of extrusion parameters on product properties can help tailored production to meet consumers' preferences and the development of functional snacks with improved nutritional quality.

Three nonconventional starch: Comparison of physicochemical properties and in vitro digestibility.

Extraction of starch from waste is also an effective way to recover resources and provide new sources of starch. In this study, starch was isolated from white kidney bean residue, chickpea residue, and tiger nut meal after protein or oil extraction, and the morphology of starch particles was observed to determine their physicochemical properties and in vitro digestibility. All these isolated starches had unique properties, among which white kidney bean starch (KBS) had a high amylose content (43.48%), and its structure was better ordered. Scanning electron microscopy revealed distinct granular morphologies for the three starches. KBS and chickpea starch (CHS) were medium-granular starches, whereas tiger nut starch was a small granular starch. Fourier transform infrared spectroscopy analysis confirmed the absence of significant differences in functional groups and chemical bonds among the three starch molecules. In vitro digestibility studies showed that CHS is more resistant to enzymatic degradation. Overall, these results will facilitate the development of products based on the separation of nonconventional starches from waste.

Humidity-Responsive Amorphous Calcium-Magnesium Pyrophosphate/Cassava Starch Scaffold for Enhanced Neurovascular Bone Regeneration.

Developing a neurovascular bone repair scaffold with an appropriate mechanical strength remains a challenge. Calcium phosphate (CaP) is similar to human bone, but its scaffolds are inherently brittle and inactive, which require recombination with active ions and polymers for bioactivity and suitable strength. This work discussed the synthesis of amorphous magnesium-calcium pyrophosphate (AMCP) and the subsequent development of a humidity-responsive AMCP/cassava starch (CS) scaffold. The scaffold demonstrated enhanced mechanical properties by strengthening the intermolecular hydrogen bonds and ionic bonds between AMCP and CS during the gelatinization and freeze-thawing processes. The release of active ions was rapid initially and stabilized into a long-term stable release after 3 days, which is well-matched with new bone growth. The release of pyrophosphate ions endowed the scaffold with antibacterial properties. At the cellular level, the released active ions simultaneously promoted the proliferation and mineralization of osteoblasts, the proliferation and migration of endothelial cells, and the proliferation of Schwann cells. At the animal level, the scaffold was demonstrated to promote vascular growth and peripheral nerve regeneration in a rat skull defect experiment, ultimately resulting in the significant and rapid repair of bone defects. The construction of the AMCP/CS scaffold offers practical suggestions and references for neurovascular bone repair.

Changes of crystalline structure and physicochemical properties of Pueraria lobata var. thomsonii starch under water deficit.

Crystal type is an important physicochemical property of starch. However, it is currently unclear whether changes in crystal type affect other properties of starch. This study discovered that water deficit resulted in an increase in small starch granules and transparency in Pueraria lobata var. thomsonii, while causing a decrease in amylose content and swelling power. Additionally, the crystal type of P. Thomsonii starch changed from CB-type to CA-type under water deficit, without significantly altering the short-range ordered structure and chain length distribution of starch. This transformation in crystal type led to peak splitting in the DSC heat flow curve of starch, alterations in gelatinization behavior, and an increase in resistant starch content. These changes in crystalline structure and physicochemical properties of starch granules are considered as adaptive strategies employed by P. Thomsonii to cope with water deficit.

Biochemical and biophysical drivers of the hydrogen isotopic composition of carbohydrates and acetogenic lipids.

The hydrogen isotopic composition (δ2H) of plant compounds is increasingly used as a hydroclimatic proxy; however, the interpretation of δ2H values is hampered by potential coeffecting biochemical and biophysical processes. Here, we studied δ2H values of water and carbohydrates in leaves and roots, and of leaf n-alkanes, in two distinct tobacco (Nicotiana sylvestris) experiments. Large differences in plant performance and biochemistry resulted from (a) soil fertilization with varying nitrogen (N) species ratios and (b) knockout-induced starch deficiency. We observed a strong 2H-enrichment in sugars and starch with a decreasing performance induced by increasing NO3-/NH4+ ratios and starch deficiency, as well as from leaves to roots. However, δ2H values of cellulose and n-alkanes were less affected. We show that relative concentrations of sugars and starch, interlinked with leaf gas exchange, shape δ2H values of carbohydrates. We thus provide insights into drivers of hydrogen isotopic composition of plant compounds and into the mechanistic modeling of plant cellulose δ2H values.