scholarly journals Encapsulation of Fruit Flavor Compounds through Interaction with Polysaccharides

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4207
Author(s):  
Ivana Buljeta ◽  
Anita Pichler ◽  
Ivana Ivić ◽  
Josip Šimunović ◽  
Mirela Kopjar
Keyword(s):  
Encapsulation Efficiency ◽  
Hydrophobic Interactions ◽  
Flavor Compounds ◽  
Coating Materials ◽  
Non Covalent Interactions ◽  
Basic Characteristics ◽  
Fruit Flavor ◽  
And Storage ◽  
Covalent Interactions ◽  
Insight Into

Production and storage, the influence of packaging materials and the presence of other ingredients in fruit products can cause changes in flavor compounds or even their loss. Due to these issues, there is a need to encapsulate flavor compounds, and polysaccharides are often used as efficient carriers. In order to achieve effective encapsulation, satisfactory retention and/or controlled release of flavor compounds, it is necessary to understand the nature of the coated and coating materials. Interactions that occur between these compounds are mostly non-covalent interactions (hydrogen bonds, hydrophobic interactions and van der Waals forces); additionally, the formation of the inclusion complexes of flavor compounds and polysaccharides can also occur. This review provides insight into studies about the encapsulation of flavor compounds, as well as basic characteristics of encapsulation such as the choice of coating material, the effect of various factors on the encapsulation efficiency and an explanation of the nature of binding.

Computational insight into the cooperative role of non-covalent interactions in the aza-Henry reaction catalyzed by quinine derivatives: mechanism and enantioselectivity

2016 ◽  
Vol 14 (40) ◽  
pp. 9588-9597 ◽  
Author(s):  
Yunsheng Xue ◽  
Yuhui Wang ◽  
Zhongyan Cao ◽  
Jian Zhou ◽  
Zhao-Xu Chen
Keyword(s):  
Hydrogen Bonding ◽  
Dft Calculations ◽  
Ion Pair ◽  
Henry Reaction ◽  
Brönsted Acid ◽  
Non Covalent Interactions ◽  
Dual Activation ◽  
Covalent Interactions ◽  
Insight Into

DFT calculations reveal the viability of the two possible ion pair-hydrogen bonding and Brønsted acid-hydrogen bonding dual activation modes.

scholarly journals Molecular determinants and bottlenecks in the unbinding dynamics of biotin-streptavidin

2017 ◽  
Author(s):  
Pratyush Tiwary
Keyword(s):  
Atomistic Simulations ◽  
Enhanced Sampling ◽  
Protein Ligand Interactions ◽  
Direct Benefits ◽  
Molecular Determinants ◽  
Bond Stretching ◽  
Ligand Interactions ◽  
Non Covalent Interactions ◽  
Covalent Interactions ◽  
Insight Into

Biotin-streptavidin is a very popular system used to gain insight into protein-ligand interactions. In its tetrameric form, it is well-known for its extremely long residence times, being one of the strongest known non-covalent interactions in nature, and is heavily used across the biotechnological industry. In this work we gain understanding into the molecular determinants and bottlenecks in the unbinding of the dimeric biotinstreptavidin system in its wild type and with N23A mutation. Using new enhanced sampling methods with full atomistic resolution, we reproduce the variation caused by N23A mutation in experimentally reported residence time. We also answer a longstanding question regarding cause/effect in the coupled events of bond stretching and bond hydration during unbinding and establish that in this system, it is the bond stretching and not hydration which forms the bottleneck in the early parts of the unbinding. We believe these calculations represent a step forward in the use of atomistic simulations to study pharmacodynamics. An improved understanding of biotin-streptavidin unbinding dynamics should also have direct benefits in biotechnological and nanobiotechnological applications.

scholarly journals Catalytic Enantioselective Synthesis of Heterocyclic Vicinal Fluoroamines Using Asymmetric Protonation: A Method Development and Mechanistic Study

2020 ◽  
Author(s):  
Matthew Ashford ◽  
Chao Xu ◽  
john molloy ◽  
Cameron Carpenter-Warren ◽  
Alexandra Slawin ◽  
...  
Keyword(s):  
Method Development ◽  
Data Bank ◽  
Enantioselective Synthesis ◽  
Mechanistic Study ◽  
Type Analysis ◽  
Conformational Landscape ◽  
Non Covalent Interactions ◽  
Chiral Bronsted Acid ◽  
Covalent Interactions ◽  
Insight Into

<div> <div> <div> <p>A catalytic enantioselective synthesis of heterocyclic vicinal fluoroamines is reported. A chiral Brønsted acid promotes aza-Michael addition to fluoroalkenyl heterocycles to give a prochiral enamine intermediate, which undergoes asymmetric protonation upon rearomatization. The reaction accommodates a range of azaheterocycles and nucleophiles, generating the C–F stereocenter in high enantioselectivity, and is also amenable to stereogenic C–CF3 bonds. Extensive DFT calculations have provided insight into the reaction mechanism and the origin of catalyst selectivity. Crystal structure data shows the dominance of non-covalent interactions in the core structure conformation, enabling modulation of the conformational landscape. Ramachandran-type analysis of conformer distribution and protein data bank mining has indicated benzylic fluorination using this approach has potential for improved potency in several marketed drugs. </p> </div> </div> </div>

Insight on the Factors Controlling the Equilibrium of Allylic Azides

2019 ◽  
Author(s):  
Margarita Vallejos ◽  
Guillermo Labadie
Keyword(s):  
Weak Interaction ◽  
Density Functional ◽  
Equilibrium Mixture ◽  
Hydroxyl Group ◽  
Functional Theory ◽  
Non Covalent Interactions ◽  
Allylic Azides ◽  
Covalent Interactions ◽  
Insight Into ◽  
Good Linear Correlation

<p>Several allylic azides with different double bond substitution were studied to understand the factors governing their equilibrium using density functional theory along with quantum theory of atoms in molecules, Non-covalent Interactions and Natural Bond Orbitals approaches. The results showed the hydroxyl group or heteroatoms in allylic azides interact with the molecule through an electrostatic weak interaction in each pair of regioisomers. The equilibrium shifts of substituted allylic azides, compared to non-substituted allylic azides, are not attributed to the presence of specific interactions, such as hydrogen bond. The observed equilibrium shifts stem mainly from the strengthening and weakening of negative hyperconjugative interactions, which is affected by the weak interaction involving the proximal substituent in each regioisomer. A good linear correlation was obtained between the hyperconjugative energies of pC=C→s*<i>Z</i><sub>b</sub> interactions and the calculated percentages of secondary azide and tertiary azides in the equilibrium mixture. Also, the effect of aromatic ring substituent was analysed using such approaches. This study not only provides insight into the factor controlling the stabilities of the substituted allylic azides, but also settle the basis to predict the regioisomer predominance in the equilibrium mixture.</p>

Non-covalent interactions in the crystallization of the enantiomers of 1,7-dioxaspiro[5.5]undecane (olive fly sex pheromone) by enantiospecific cyclodextrin hosts, hexakis(2,3,6-tri-O-methyl)-α-cyclodextrin and heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin

2001 ◽  
Vol 57 (3) ◽  
pp. 399-409 ◽  
Author(s):  
Stella Makedonopoulou ◽  
Konstantina Yannakopoulou ◽  
Demetrios Mentzafos ◽  
Victor Lamzin ◽  
Alexander Popov ◽  
...  
Keyword(s):  
Sex Pheromone ◽  
Intermolecular Forces ◽  
Racemic Mixture ◽  
Olive Fly ◽  
Non Covalent Interactions ◽  
First Time ◽  
Weak Intermolecular Forces ◽  
Covalent Interactions ◽  
Insight Into

The enantiomers of racemic olive fly sex pheromone 1,7-dioxaspiro[5.5]undecane (1) have been isolated by crystallization with enantiospecific cyclodextrin hosts: (S)-(1) crystallizes with heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin (TMβCD) and (R)-(1) with hexakis(2,3,6-tri-O-methyl)-α-cyclodextrin (TMαCD). The crystal structure of TMβCD/(S)-(1) from synchrotron radiation data at 100 K, determined for the first time, proves that TMβCD crystallizes with only the (S)-enantiomer from the racemic mixture. Comparison with the 100 K structure of TMαCD/(R)-(1) redetermined with synchrotron data has provided insight into the interactions between each of the hosts with the corresponding enantiomeric guests. Owing to the high resolution of the data and the unusually high quality of the crystals, localization of the H atoms has been achieved, a rare accomplishment for cyclodextrin X-ray structures. This made possible, apart from the geometry of the complexes, the detailed description of a five-membered-ring water cluster with very well ordered hydrogen bonding. The enantiospecificity exhibited by the described systems reveals the subtle differences of the weak intermolecular forces involved in the selective binding of the two optical antipodes by the two hosts. The binding geometry in the two complexes is different, but it is effected in both by numerous host–guest C—H...O interactions, resulting from induced fit of the hosts toward each of the enantiomeric guests. In TMαCD/(R)-(1) two of these H...O host–guest distances, directed toward the acetal O atoms defining the chirality of the guest, are much shorter than the rest and also shorter than all the H...O distances in TMβCD/(S)-(1). Moreover, (R)-(1) interacts not only with the enclosing host, but with other hosts in the crystal lattice, in contrast to (S)-(1) in the TMβCD/(S)-(1) complex which is isolated inside channels formed by the host molecules. The above differences are reflected in the much higher binding constant of TMαCD/(R)-(1) compared with that of TMβCD/(S)-(1) (∼6800 and ∼935 M−1, respectively), determined by NMR in aqueous solution, and the ability of TMαCD to selectively precipitate (R)-(1) from racemic (1) in much higher yield than TMβCD precipitates (S)-(1).

scholarly journals Cover Feature: An Insight into Non‐Covalent Interactions on the Bicyclo[1.1.1]pentane Scaffold (Eur. J. Org. Chem. 7/2021)

2021 ◽  
Vol 2021 (7) ◽  
pp. 1036-1036
Author(s):  
Nitika Grover ◽  
Keith J. Flanagan ◽  
Cristina Trujillo ◽  
Christopher J. Kingsbury ◽  
Mathias O. Senge
Keyword(s):  
Non Covalent Interactions ◽  
Covalent Interactions ◽  
Insight Into
Sign in / Sign up

Export Citation Format

Share Document