Electrospun curcumin-loaded protein nanofiber mats as active/bioactive coatings for food packaging applications

TLDR: In this paper, curcumin was encapsulated within electrospun protein (ie gelatin and zein) fibers to generate bioactive coatings for food packaging Additionally, green tea extract (GTE) was also incorporated within the formulations to evaluate its impact on the stability, protective ability, and release properties of the cumin-loaded fibers.

About: This article is published in Food Hydrocolloids.The article was published on 2019-02-01 and is currently open access. It has received 116 citations till now. The article focuses on the topics: Gelatin & Controlled release.

Figures

Figure 6 shows DTG curves of the prepared coatings. Although the incorporation of 518 curcumin within the zein fibers did not modify their thermal stability, most probably due to 519 the low curcumin to zein ratio employed, the degradation of the gelatin fibers occurred at a 520 slightly lower temperature when they were loaded with curcumin. In this latter case, the 521 bioactive compound was incorporated in the form of liposomal curcumin, and phospholipids 522 have been previously described to interact with proteins through hydrophobic interactions, 523 altering their secondary structure (Kasinos et al., 2013). 524 525

Figure 5 shows the FT-IR spectra of gelatin and zein fibers containing curcumin, both in the 476 presence and in the absence of GTE, together with the spectrum of the commercial GTE. FT-477 IR spectra are presented in absorbance mode. 478 The characteristic bands of proteins, i.e. amide A or N-H stretching (3287 cm-1), amide B or 479 asymmetric stretching vibration of =C-H and –NH3+ (3071 cm-1 for gelatin and 3058 cm-1 for 480 zein), amide I or C=O stretching (1629 cm-1 for gelatin and 1647 cm-1 for zein), amide II or 481

Table 1. Average size and polydispersity index (PDI) of the prepared phosphatidylcholine liposomes* 307

Fig. 3 S in the a with the

Table 2. Curcumin encapsulation efficiency (%) for the developed coatings 414

Frequently asked questions

Q1. What are the contributions in "Electrospun curcumin-loaded protein nanofiber mats as active/bioactive" ?

In this paper, the authors proposed an approach for the design of bioactive or functional food packaging materials to incorporate beneficial bioactive ingredients within them, which must be then released towards the food products in a controlled manner during their shelf life. 

Q2. What are the two proteins that have been shown to form electrospun fibers?

In particular, zein and gelatin are two 98 proteins whose ability to form electrospun fibers has been already demonstrated (Lu et al., 99 2015; Yao et al., 2018). 

Q3. What are the advantages of electrospun nanofibers for food packaging?

Electrospun 78 nanofibers present particular benefits for the production of food packaging coatings, such as 79 higher crack resistance as compared to conventional films, absence of negative impact in the 80 flexibility and mechanical properties of the packaging material to be coated and their good 81 adhesion properties due to their large surface to volume ratio (Fabra, Busolo, Lopez-Rubio, & 82 Lagaron, 2013). 

Q4. How is the bioactive material incorporated into the bulk packaging material?

Since most bioactive 50 compounds are highly sensitive, and may be degraded during the usual thermal processing of 51 plastics and bioplastics, their direct incorporation within the bulk packaging material is not 52 feasible in practice (Fabra, López-Rubio, & Lagaron, 2016). 

Q5. What is the effect of the addition of co-687 on the zein 698 fiber?

The higher stability of the zein 697 fibers in water and its better release performance in the polar food simulant, suggest that zein-698 based coatings would be more adequate for surfaces in contact with food products possessing 699 high water contents. 

Q6. How was the curcumin release in the gelatin coatings?

In this case, the curcumin release from the zein coatings was almost 623 negligible, while gelatin fibers released up to about 18% of their curcumin content in a 624 sustained manner. 

Q7. What was the absorption of curcumin in the protein fibers?

curcumin-loaded protein fibers were dispersed in 248 PBS (pH = 7.4) to achieve theoretical curcumin concentrations of 0.01 mg/ml. 

Q8. What were the interactions between the gelatin and the surface of the liposomes?

These interactions were 684       35  seen to be detrimental for the thermal stability of the gelatin fibers and responsible for the 685 greater and faster release of curcumin in these coatings. 

Q9. What was the method used to determine the structural changes undergone by the gelatin solutions when being?

In order to assess the structural changes undergone by the liposomes when being subjected to 223 the electrospinning process, the gelatin solutions with liposomes and the generated 224 electrospun fibers were characterized by means of SAXS experiments following the method 225 described in Section 2.4.2. 

Q10. how did the gelatin 661 coatings react with food simulants?

These results confirmed that, while the developed gelatin 661 coatings showed a promising release behavior in contact with fatty food simulants, they were 662 not adequate vehicles to achieve a sustained migration of curcumin to food products with 663 high water content. 

Q11. What is the effect of the addition of 693 GTE on the gelatin fibers?

the addition of 693 GTE was not able to prevent the collapse of the gelatin fibers in water, evidencing the fact 694 that this system would be more suitable for the development of coatings intended for the 695 preservation of fatty food products.