Use of jackfruit leaf (Artocarpus heterophyllus L.) protein hydrolysates as a stabilizer of the nanoemulsions loaded with extract-rich in pentacyclic triterpenes obtained from Coccoloba uvifera L. leaf

Abstract

This study aimed to evaluate the encapsulating potential of a jackfruit leaf protein hydrolysate, through obtaining pentacyclic triterpenes-rich extract loaded nanoemulsion. Response surface methodology (RSM) was used to optimize the conditions to obtain an optimal nanoemulsion (NE-Opt). The effect of protein hydrolysate concentration (0.5-2%), oil loaded with extract (2.5-7.5%), and ultrasound time (5-15 min) on the polydispersity index (PDI) and droplet size of the emulsion (D[3,2] and D[4,3]) was evaluated. RSM revealed that 1.25% protein hydrolysate, 2.5% oil, and ultrasound time of 15 min produced the NE-Opt with the lowest PDI (0.85), D[3,2] (330 nm), and D[4,3] (360 nm). Encapsulation efficiency and extract loading of the NE-Opt was of 40.15 ± 1.46 and 18.03 ± 2.78% respectively. The NE-Opt was relatively stable during storage (at 4 and 25 °C), pH, temperature, and ionic strength. Then, the protein hydrolysate could be used as an alternative to conventional emulsifiers.

Keywords: Coccoloba uvifera L.; Hexane (PubChem CID: 8058); Hydrochloric acid (HCl, PubChem CID: 313); Jackfruit leaf; Leaf protein hydrolysates; Methanol (PubChem CID: 887).; Nanoemulsion O/W; Pancreatin (EC 232-468-9); Pentacyclic triterpenes extract; Sodium hydroxide (NaOH, PubChem CID: 14798).

Fig. 1

Desirability surface plots of the interactions between oil loaded with extract-protein hydrolysate (A), ultrasound time-protein hydrolysate (B), and ultrasound time-oil loaded with extract (C).

Fig. 2

Linear correlation plots between experimental and predicted values of PDI (A), D[3,2] (B), and D[4,3] (C) and particle size distribution (D) of the NE-Opt.

Fig. 3

Emulsion stability index (ESI) of NE-Opt during the storage [4 (□) and 25(■) °C] (A), pH (B), temperature (C), and NaCl concentration (D). Different letters indicate significant differences (P < 0.05) between treatments. Lines are for the guidance of reader.

Fig. 4

Evolution of the NE-Opt color parameters during storage at 25 (■) and 4 (□) °C: A) L*: Lightness; B) a*: redness; C) b*: yellowness and D) ΔE: Total color difference. ^{a–b or á–b́}indicate significant differences (P < 0.05) between emulsions stored at 0, 15, and 30 days for temperatures of 25 and 4 °C, respectively. Lines are for the guidance of readers.

Fig. 5

Thermal analysis of emulsion and its components: A) DSC and B) TGA of H-pan (), triterpenic extract (), oil olive (), NE-Opt without extract () and with extract ().