Techno-functional properties of active film based on guar gum-propolis and its application for "Nanguo" pears preservation.

Guar gum (GG) composite films, incorporating the ethanolic extract of propolis (EEP), were prepared and subjected to a comprehensive investigation of their functional characteristics. The addition of EEP resulted in a discernible enhancement in the opacity, moisture barrier capacity, and elongation at break. Incorporating EEP led to a noteworthy increase in the total phenolic and total flavonoid content of the films, resulting in superior antioxidant capacity upon GG-EEP films. Remarkably, the addition of 5 % EEP yielded noteworthy outcomes, manifesting in a DPPH radical scavenging rate of 47.60 % and the ABTS radical scavenging rate of 94.87 %, as well as FRAP and cupric reducing power of 331.98 mmol FeSO4-7H2O kg-1 and 56.95 µg TE mg-1, respectively. In addition, GG-EEP films demonstrated antifungal effect against Penicillium expansum and Aspergillus niger, along with a sustained antibacterial effect against Escherichia coli and Staphylococcus aureus. GG-EEP films had superior inhibitory ability against Gram-positive bacteria than Gram-negative bacteria. Crucially, GG-EEP composite films played a pivotal role in reducing both lesion diameter and depth, concurrently mitigating weight loss and firmness decline during the storage period of "Nanguo" pears. Therefore, GG-EEP composite films have the considerable potential to serve as advanced and effective active packaging materials for food preservation.

Improved sustained-release properties of ginger essential oil in a Pickering emulsion system incorporated in sodium alginate film and delayed postharvest senescence of mango fruits.

The insufficient water vapor barrier and mechanical capacity of sodium alginate (SA) film limited its application in fruit preservation. Herein, cellulose nanocrystals (CNCs) were used to stabilize Pickering emulsion. Then, we prepared SA composite films. Ginger essential oil (GEO) was loaded as antimicrobials and antioxidants. Finally, the application on mangos were investigated. Compared to coarse emulsion, Pickering emulsion and its film-formation-solution showed more stable system and larger droplet size. The emulsion significantly changed the properties of SA film. Specifically, CNCs improved the thermal, tensile, and barrier properties of the film and GEO enhanced the ultraviolet-visible light barrier capacity. Additionally, the SA/CNC film possessed a homogeneous micromorphology which had a sustained-release effect on GEO, thus maintaining high postharvest quality and long-term bioavailability for mangos. In conclusion, the film prepared via Pickering emulsion showed satisfactory properties which had great potential in fruit preservation.

Polysaccharide-based biosorbents for cholesterol and bile salts in gastric-intestinal passage: Advances and future trends.

Cholesterol is one of the hazard elements for many cardiovascular diseases, but many cholesterol-lowering drugs are expensive and unhealthy. Therefore, it is necessary to develop edible and safe biosorbents to reduce excess cholesterol and bile salts in the gastric-intestinal passage. Polysaccharide-based biosorbents offer a feasible strategy for decreasing them. This review summarized polysaccharide-based biosorbents that have been developed for adsorbing cholesterol and bile salts from the gastric-intestinal passage and analyzed common modification methods for these adsorbents. Finally, the adsorption models were also elucidated. Polysaccharides, including ß-cyclodextrin, pectin, chitin/chitosan, dietary fiber extract, and cellulose, have been proposed for adsorbing cholesterol and bile salts in the gastric-intestinal passage as biosorbents. This is mainly due to the retention of pores, the capture of the viscosity network, and the help of hydrophobic interactions. In spite of this, the adsorption capacity of polysaccharides is still limited. Therefore, the modifications for them became the most popular areas in the recent studies of in vitro cholesterol adsorption. Chemical approaches namely grafting, (1) acetylation, (2) hydroxypropylation, (3) carboxymethylation, and (4) amination are considered to modify the polysaccharides for higher adsorption ability. Moreover, ultrasonic/microwave/pressure treatment and micron technology (microfluidization, micronization, and ball milling) are effective physical modification methods, while the biological approach mainly refers to enzymatic hydrolysis and microbial fermentation. The adsorption models are generally explained by two adsorption isotherms and two adsorption kinetics. In sum, it is reckoned that further food applications will follow soon.

Soluble polysaccharides decrease inhibitory activity of banana condensed tannins against porcine pancreatic lipase.

The inhibition of soluble polysaccharides (SPs) (arabic gum, dextran and pectin from citrus) on the binding between banana condensed tannins (BCTs) and pancreatic lipase (PL) was studied from variant aspects. Molecular docking simulations predicted that BCTs strongly bound SPs and PL through non-covalent interactions. The experimental results showed that SPs reduced the inhibition of BCTs on PL, and the IC50 value increased. However, the addition of SPs did not change the inhibitory type of BCTs on PL, which all were non-competitive inhibition. BCTs quenched PL fluorescence through static quenching mechanism and changed the secondary structure of PL. The addition of SPs alleviated the trending. The effect of SPs on the binding of BCTs-PL was mainly due to the strong non-covalent interaction between SPs and BCTs. This study emphasized that attention should be paid to the counteracting effects of polysaccharides and polyphenols in dietary intake to maximize their respective roles.

Advances in propolis and propolis functionalized coatings and films for fruits and vegetables preservation.

Propolis, as a natural active substance, is rich in polyphenols, with low toxicity, antioxidant, antifungal and antibacterial properties, which can be applied to the post-harvest preservation of fruits and vegetables. Propolis extracts and propolis functionalized coatings and films have exhibited good freshness in various types of fruits and vegetables as well as fresh-cut vegetables. They are mainly used to prevent water loss after harvesting, to inhibit the infestation of bacteria and fungi after harvesting and to enhance the firmness and apparent quality of fruits and vegetables. Moreover, propolis and propolis functionalized composites have a small or even insignificant effect on the physicochemical parameters of fruits and vegetables. Furthermore, how to cover the special smell of propolis itself so that it does not affect the flavor of fruits and vegetables, and the application of propolis extract in wrapping paper and packaging bag of fruits and vegetables, are worthwhile to further investigate.

A comprehensive review of intelligent packaging for fruits and vegetables: Target responders, classification, applications, and future challenges.

Post-harvest fruits and vegetables are extremely susceptible to dramatic and accelerated quality deterioration deriving from their metabolism and adverse environmental influences. Given their vigorous physiological metabolism, monitoring means are lacking due to the extent that unnecessary waste and damage are caused. Numerous intelligent packaging studies have been hitherto carried out to investigate their potential for fruit and vegetable quality monitoring. This state-of-the-art overview begins with recent advances in target metabolites for intelligent packaging of fruits and vegetables. Subsequently, the mechanisms of action between metabolites and packaging materials are presented. In particular, the exact categorization and function of intelligent packaging of fruits and vegetables, are all extensively and comprehensively described. In addition, for the sake of further research in this field, the obstacles that impede the scaling up and commercialization of intelligent packaging for fruits and vegetables are also explored, to present valuable references.

Development and characterization of a novel active and intelligent film based on pectin and betacyanins from peel waste of pitaya (Hylocereus undatus).

In the present study, peel waste of pitaya (Hylocereus spp.) was used to develop a novel active and functional film. The film was developed with a combination of the white-fleshed pitaya peel pectin (WPPP) as a biopolymer and white-fleshed pitaya peel betacyanins (WPPB) as an active constituent, respectively. Furthermore, montmorillonite (MMT), a cheap and environmental-friendly silicate material, was introduced into film matrix as a filler to reduce the moisture sensitivity of the film. The effect of the incorporation of WPPB on the properties of WPPP/MMT films was investigated. The colorimetric response of WPPP/MMT/WPPB to pH and ammonia was examined, respectively. Moreover, WPPP/MMT/WPPB-2 was employed to monitor the freshness of shrimp. The color of the film changed from redness to reddish-brown, and further to brownness, echoing the shrimp turned from fresh to spoiled. Therefore, WPPP/MMT/WPPB-2 composite films showed promise for the applications in monitoring the freshness of shrimp.

Q-Switched Laser Combined with Intense Pulsed Laser in the Treatment of Melasma Based on Reflection Confocal Microscope.

Chloasma is a prevalent clinical hyperpigmentation skin disorder that causes symmetrical brown to tan patches on the cheeks, as well as the neck and forearms on rare occasions. The pathophysiology of this condition is complicated, and there is now no cure. Under the light microscope, the full-thickness melanin of the epidermis in the skin lesions was increased, and the dermal chromophages increased. At present, the treatment of melasma mainly includes topical drugs, chemical peels, systemic drugs, laser therapy, and traditional Chinese medicine. With the development of medical technology, intense pulsed light and Q-switched laser have been widely used in the treatment of melasma, which can emit laser beams to penetrate the dermis uniformly to treat deep pigmented lesions in the dermis. After a stable treatment outcome for melasma is achieved, it is important to minimize side effects such as postinflammatory hyperpigmentation and skin irritation. Therefore, this paper uses a reflection confocal microscope to establish an evaluation index system and then uses a neural network to evaluate the treatment effect. The work of this paper is as follows: (1) this paper introduces various methods of treating melasma at home and abroad and focuses on the application of intense pulsed light therapy and low-energy Q-switched Nd: YAG laser in the treatment of melasma. (2) In this paper, the case data samples are trained with the designed BP network to obtain a reliable evaluation network model. (3) The results and mistakes of the evaluation are produced by training the genetic algorithm optimized backpropagation (GA-BP) network structure model to evaluate the treatment effect of chloasma. Finally, it has been demonstrated that the GA-BP network has great accuracy and stability.

Anti-diabetic and anti-obesity: Efficacy evaluation and exploitation of polyphenols in fruits and vegetables.

Polyphenols are a group of secondary plant metabolites widely present in diets and have antagonistic effects on some chronic metabolic diseases, like type 2 diabetes (T2D) and obesity. We attempt to investigate the effects of polyphenols in fruits and vegetables on reducing the risk of T2D and obesity by collecting epidemiological evidence, including cross-sectional survey (CSS), prospective cohort study (PCS), and randomized controlled trial (RCT). Further, we provide possible mechanisms for the anti-diabetic effects including protecting pancreatic ß-cells, affecting glucose digestion, absorption, and uptake, and activating glucose/lipid metabolism pathways, while improving obesity by reducing lipid accumulation, regulating intestinal microflora, alleviating inflammation, and reducing food intake. Polyphenols also play an important role in the relationship between T2D and obesity. On the one hand, obesity is a low-grade chronic inflammation causing insulin resistance, so polyphenols can reduce T2D risk by improving obesity. On the other hand, obesity decreases the polyphenols bioavailability by disturbing gastrointestinal microflora, thus increasing T2D risk. These are instructive for diets and bring considerable development value. Therefore, we discussed the hotspots of polyphenols exploitation in the food industry, including masking bitter and astringent taste, ensuring stability, and improving the bioavailability, which provides ideas for polyphenols application in anti-diabetics and anti-obesity.

Highly sensitive fluorescent sensing platform for imidacloprid and thiamethoxam by aggregation-induced emission of the Zr(â £) metal - organic framework.

A novel luminescent UiO-66-NH2 (UN) demonstrated great potentials to sense imidacloprid (IM) and thiamethoxam (TH) pesticides with high sensitivity and desirable selectivity. The UN exhibits superb luminescence emission properties, which have been found to enhance the aggregation-induced emission (AIE) of IM and TH. The enhanced AIE of IM and TH on UN has been applied for the sensitive sensing of IM and TH, and a limit of detection (LOD) of IM was estimated to be 5.57 µg/L. LOD of TH was found to be 0.98 µg/L, respectively. Interestingly, the other neonicotinoid pesticides showed a low interference response in recognition of IM and TH. More importantly, we have further demonstrated that the UN are successfully used to sense IM and TH in real samples of fruit juice with a high recovery of 85-116%, and relative standard deviation (RSD) were from 3.42% to 16.07%.

Potential Hypolipidemic Effects of Banana Condensed Tannins Through the Interaction with Digestive Juice Components Related to Lipid Digestion.

An in vitro intestinal model was used to evaluate the impact of banana condensed tannins (BCT) on the digestion of lipids (fat and cholesterol). BCT significantly suppressed the digestion of fat and cholesterol by interacting with digestive juice components. The interactions of BCT with a digestive juice mixture and its components (including bile acid, lipase, cholesterol esterase, CaCl2, NaCl, and cholesterol) were analyzed using turbidity, isothermal titration calorimetry, particle size distribution, zeta potential, and molecular docking analyses. The results showed that BCT reduced the digestion of lipids mainly via interaction with lipase, cholesterol esterase, bile acid, and cholesterol. Electrostatic CT-calcium ion complexes might reduce the extent of lipid digestion by decreasing the surface area of the lipid droplets exposed to the enzymes. This research provides valuable insights into the molecular mechanisms of the interaction of BCT with digestive juice components related to lipid digestion that may affect the rate and extent of lipid digestion.

Zirconium(â £)-based metal-organic framework for determination of imidacloprid and thiamethoxam pesticides from fruits by UPLC-MS/MS.

Zirconium(Ⅳ)-based metal-organic framework (MOF)-UiO-66-NH2 was fabricated to adsorb the imidacloprid and thiamethoxam in fruit samples before analysis using UPLC-MS/MS. The UiO-66-NH2 was confirmed by SEM, FTIR, and XRD. Key experimental parameters were investigated by response surface methodology (RSM). The desirability recovery of imidacloprid was 94.52% under optimum conditions (mount of adsorbent = 52.48 mg, volume of eluent = 5.18 mL, pH = 9, extraction time = 15 min). The desirability recovery of thiamethoxam was 93.57% under optimum conditions (mount of adsorbent = 50.58 mg, volume of eluent = 2.6 mL, pH = 5.65, extraction time = 11.94 min). Under the optimal conditions, the actual recovery of imidacloprid and thiamethoxam was 92.39% and 94.37%, respectively. Besides, the method was applied successfully to detect imidacloprid and thiamethoxam in different fruit samples. The results demonstrated that the UiO-66-NH2 is an excellent adsorbent for the extraction imidacloprid and thiamethoxam from fruit samples.

Inhibitory Effect of Condensed Tannins from Banana Pulp on Cholesterol Esterase and Mechanisms of Interaction.

In the present study, the inhibitory effect of condensed tannins (CTs) on cholesterol esterase (CEase) was studied. The underlying mechanisms were evaluated by reaction kinetics, turbidity and particle size analyses, multispectroscopy methods, thermodynamics, and computer molecular simulations. CTs showed potent CEase inhibitory activity with an IC50 value of 64.19 µg/mL, and the CEase activity decreased with increasing CT content in a mixed-competitive manner, which was verified by molecular docking simulations. Fluorescence and UV-vis measurements revealed that complexes were formed from CEase and CTs by noncovalent interaction. Isothermal titration calorimetry indicated that the interaction between CEase and CTs occurred through hydrogen bonding and hydrophobic interactions. Circular dichroism analysis suggested that CTs inhibited the activity of CEase by altering the secondary structure of CEase. The inhibition of CTs on CEase in the gastrointestinal tract might be one mechanism for its cholesterol-lowering effect.