Effect of chitosan molecular weight as micro and nanoparticles

The objective of the present research was to compare antibacterial activity of three CS with different MWs microparticle as well as their nanoparticles forms against three pathogenic bacteria including:

Several studies have shown that the biological activity of CS depends significantly on its molecular weight ; however, most studies involve only one or two different MWs of CSs.

Moreover, to our best knowledge, there is no comparative study on the antibacterial activities of CSNPs prepared from CSwith different MWs against pathogenic bacteria.

Therefore, the objective of the present research was to compare antibacterial activity of three CS with different MWs microparticle as well as their nanoparticles forms against three pathogenic bacteria including:.

WHAT YOU CAN LEARN

The reduction in the OD of cell suspension depends on the type of CS microparticles, CSNPs and the species of bacteria.

However, MVCN exhibit higher antibacterial activity than MVC itself against all bacterial cultures tested.

It is anticipated that CSNPs could be applied broadly as antimicrobial agents in medicine and food science for their high antibacterial activity and acceptable biocompatibilities.

References:

https://doi.org/10.6084/m9.figshare.8993789

https://figshare.com/s/87b24409667ad8f4ae58

https://www.sciencedirect.com/science/article/pii/S0023643816301943

Postharvest treatment of nanochitosan-based coating loaded with Zataria multiflora essential oil improves antioxidant activity and extends shelf-life of cucumber

One of the main objectives of postharvest technology in fruits and vegetables is to delay senescence symptoms.

In keeping with this, the present study aimed to assess the effect of the chitosan nanoparticles and Z. multiflora essential oil incorporated into chitosan nanoparticle coatings on the physicochemical quality, microbial characteristics, respiration rate, and antioxidant properties of the cucumber during storage at 10 1 C with 9095% relative humidity.

Zataria multiflora Boiss essential oil, with a very high percentage of thymol and carvacrol as well as significant antioxidant, antibacterial and antifungal properties, appears as promising natural compound for controlling postharvest decay in fruits.

In this regard, the nano-/micro-encapsulation of EOs allows protection of their sensitive bioactive compounds from unfavorable environmental conditions and enhances their bioactivity during food processing and storage.

WHAT YOU CAN LEARN

Several conclusions can be drawn from the experimental work reported here.

First, the use of ZEO placed inside nanoparticles of chitosan offers an efficient option for extending the shelf-life of cucumber fruit at storage temperature.

This type of edible coating with the lowest decay level of cucumbers is more efficient than the use of CSNPs alone, probably due to the release of active compounds by the nanoparticles.

Therefore, these results suggest that the ZEO@CSNPs could be applied to the cucumber coating to extend the shelf life with higher antioxidant activity.

Ref:
https://doi.org/10.6084/m9.figshare.8378729

Ref: https://www.sciencedirect.com/science/article/pii/S1466856415002076

Ref: https://figshare.com/s/daa623cce532dffe8663

Nanoencapsulation of Zataria multiflora essential oil preparation and characterization with enhanced antifungal activity for controlling Botrytis cinerea, the causal agent of gray mould disease

The present study was set to encapsulate hydrophobic Zataria multiflora essential oil (ZEO) in chitosan nanoparticles (CSNPs) using ionic gelation technique in order to enhance antifungal activity and stability of the oils against B. cinerea.

The application of plant essential oil treatment at pre- or postharvest stage has been considered as an alternative treatment to the use of synthetic fungicides to prevent fruit postharvest decay and to extend the storage life while retaining the overall quality of different fresh commodities.

Although EOs have proved to be good antimicrobial agents, their use for maintaining fruit quality and reducing fungal decay is often limited due to their volatile compounds which can easily suffer degradation under the action of heat, pressure, light and oxygen.

Nano-/micro-encapsulation technology of these compounds can be a practical and efficient approach to solve some of these problems such as the physical instability and enhance their bioactivity, while at the same time, controlling fruit postharvest decay, by lowering the diffusion processes and maintaining high concentrations of active molecules on the surface of the fruit.

WHAT YOU CAN LEARN

CSNPs, a prospective carrier for sustained release of ZEO, were prepared by a modified ionotropic gelation method and characterized by UV-vis spectrophotometry, DLS and TEM.

The release of ZEO from CSNPs in buffer solutions with pH of 3, 5 and 7 followed a Fickian behavior.

The superior performance of ZEO when encapsulated by CSNPs under both in vitro and in vivo conditions in comparison with free oils was revealed.

Ref: https://doi.org/10.6084/m9.figshare.8320886

Chitosan nanoparticles loaded with Cinnamomum zeylanicum essential oil enhance the shelf life of cucumber during cold storage

This oomycete causes damping off, gummosis and fruit rot in many vegetable crops such as Cucurbitaceae and Solanaceae families.

Additionally, encapsulation could improve water solubility, control the delivery, improve absorption, and reduce the toxicity and cost of bioactive compounds due to the reduction of the required quantity.

While microcapsules may guarantee protection of antimicrobial compounds against evaporation or degradation, nanoencapsulation systems, due to high surface area to volume ratios, have versatile advantages for targeted site-specific delivery and efficient absorption through cells that could lead to higher antimicrobial activity.

WHAT YOU CAN LEARN

In this study, chitosan nanoparticles loaded with CEO were prepared with size range of 100190 nm, loading capacity of 34%, and encapsulation efficiency of 217%.

The superior performance of CEO when encapsulated by CSNs in comparison with free oils and CSNs was demonstrated.

Furthermore, the CEO-CSNs was more effective than pure CSNs coating at reducing respiration rates, improving the microbiological quality, preserving the fruit weight and quality of cucumbers during the storage period.

These results demonstrate the potential of CSNs containing cinnamon oil for coating cucumbers to extended the postharvest shelf life.

Ref: https://doi.org/10.6084/m9.figshare.8321027