In this paper, we demonstrate for the first time the use of gliadin particles to structure algal oil (rich in DHA) and to exert chemical stability against lipid oxidation via the Pickering high internal phase emulsion (HIPE) strategy. The gliadin/chitosan colloid particles (GCCPs) were effectively adsorbed and anchored at the algal oil–water interface. Concomitantly, the particle-coated droplets as building blocks constructed a percolating 3D-network framework, endowing Pickering HIPEs with viscoelastic and self-supporting attributes. In addition, Pickering HIPEs loaded with shell (HIP-curEs) or core curcumin (HIPEs-cur) were constructed to depress the oxidation of algal oil. The content of primary (lipid hydroperoxides) and secondary (malondialdehyde and hexanal) oxidation products in HIPEs was lower than that in bulk oil. The oxidative stability of HIPEs was further improved in shell and core curcumin. An in vitro gastrointestinal (GI) model was constructed to characterize the lipid digestion, lipid oxidation as well as curcumin bioaccessibility of the ingested Pickering HIPEs. Lipid oxidation in the Pickering HIPEs was retarded under GI fluids, especially in the presence of core curcumin. The free fatty acid (FFA) fraction released was below 30% for all HIPEs, reflecting that the Pickering HIPEs formed restrict the digestion of fat or oil and potentially help to fight obesity. Interestingly, this route enhanced the bioaccessibility of curcumin from only 2.13% (bulk algal oil) to 53.61% (core curcumin); in particular, it reached 76.82% for shell curcumin. These results help to fill the gap between the physicochemical performance of the gliadin particle stabilized Pickering HIPEs and their potential applications as oral delivery systems of nutraceuticals. This work opens concomitantly an attractive strategy to convert liquid oils into antioxidant soft solids without artificial trans fats, as a potential alternative for PHOs.

Avocado is an important tropical fruit with high commercial value, but has a relatively short storage life. In this study, the effects of cold shock treatment (CST) on shelf life of naturally ripened and ethylene-ripened avocado fruits were investigated. Fruits were immersed in ice water for 30 min, then subjected to natural or ethylene-induced ripening. Fruit color; firmness; respiration rate; ethylene production; and the activities of polygalacturonase (PG), pectin methylesterase (PME), and endo-β-1,4-glucanase were measured. Immersion in ice water for 30 min effectively delayed ripening-associated processes, including peel discoloration, pulp softening, respiration rate, and ethylene production during shelf life. The delay in fruit softening by CST was associated with decreased PG and endo-β-1,4-glucanase activities, but not PME activity. This method could potentially be a useful postharvest technology to extend shelf life of avocado fruits.

The mechanism regulating procyanidin (PA) accumulation in banana ( Musa acuminata ) fruit is not understood. During this study, the effects of PA treatment on the activities of banana PA biosynthetic enzymes and transcriptomic profiles were investigated. The results showed that PA treatment delayed the decreases in leucoanthocyanidin reductase and anthocyanidin reductase activities, which affected the accumulation of PA. Furthermore, the peel samples of the control fruit and the PA-treated fruit on day 1 were selected for transcriptomic analysis. The results revealed that PA treatment induced 1086 differentially expressed genes. Twenty-one key genes, including those encoding biosynthetic enzymes and regulatory factors involved in PA biosynthesis, were validated using a quantitative real-time polymerase chain reaction. The results showed that these genes were upregulated by PA treatment during banana storage. Taken together, our study improves current understanding of the mechanism underlying PA-regulated banana senescence and provide new clues for investigating specific gene functions.

Many reports indicate that an abundance of really interesting new gene (RING) play key roles in regulating defense responses against abiotic and biotic stresses in plants. In this study, the cloning and functional characterization of a RING gene, MaRING2 , in banana ( Musa acuminata ) fruit are reported. MaRING2 belongs to the NEP1-interacting protein (NIP) RING-H2 finger protein family. Gene expression profiles revealed that MaRING2 was cold responsive and induced by abscisic acid (ABA) treatment during cold storage. In this study, the MaRING2 under control of the Cauliflower mosaic virus 35S (CaMV 35S) promoter was transformed to tobacco ( Nicotiana benthamiana ) using agrobacterium ( Agrobacterium tumefaciens )-mediated transformation. The resultant MaRING2 -overexpressing transgenic plants ( 35S:MaRING2 ) exhibited significantly increased tolerance to low temperatures and were hypersensitive to exogenous ABA in terms of germination and early seedling growth. In addition, overexpression of MaRING2 enhanced the expression of stress-responsive genes under normal (before cold stress) or cold conditions. These results demonstrate the biological role of MaRING2 in conferring cold tolerance. Taken together, these results suggest that MaRING2 , a C3H2C3-type RING protein, is a positive regulator of the ABA-dependent stress response.