Fabrication and characterization of novel antibacterial chitosan/dialdehyde guar gum hydrogels containing pomegranate peel extract for active food packaging application.

This study aimed to investigate synthesis and structural characteristics of the chitosan (CS) - modified dialdehyde guar gum (DAGG) hydrogel through the Schiff base reaction. The highest swelling capacity was achieved as about 12,000% of dry weight of the freeze-dried powder at CS: DAGG hydrogel with the mixing ratio of 30:70. The swelling ratio was not affected by changes in pH, which could be considered as an important property in the control of moisture in absorbent pad. The FTIR results indicated that the new amide groups have been formed at 1680 cm-1, which can be attributed to the covalent bond between the amide groups of CS and the aldehyde groups of GG. Based on a SEM image, the prepared hydrogel showed the porous structure so it verified the crosslinking formation between the two polymers. Rheological analyses confirmed that formation compact and porous structure led to some noteworthy improvements in the strength of hydrogel prepared with a high ratio of DAGG. The hydrogel loaded with 5% pomegranate peel extract (PPE) showed both good antioxidant (81.13%) and antimicrobial activities. The hydrogel was observed to have a good potential to be used as an antibacterial pad.

A Comprehensive Review on the Chemical Constituents and Functional Uses of Walnut (Juglans spp.) Husk.

The walnut (Juglans spp.) is an appreciated nut that belongs to the Juglandaceae family. The fruit includes four main parts: the kernel, the skin, the shell, and the green husk. It is widely cultivated due to its edible kernel. In walnut production centers, high amounts of the husk as an agro-forest waste product are produced and discarded away. Recently, it has been demonstrated that the walnut green husk could be valued as a source of different natural bioactive compounds with excellent antioxidant and antimicrobial properties. Regarding this respect, in this contribution, the current scientific knowledge on the antioxidant and antiradical activities, various identified and isolated individual chemical constituents, as well as the functional applications of the walnut husk with more emphasis on the Persian walnut (Juglans regia L.) are reviewed.

The beneficial effects of almond (Prunus amygdalus Batsch) hull on serum lipid profile and antioxidant capacity in male rats.

BACKGROUND/AIM: Almond hull is produced in high amounts and mostly used as livestock feed. This study was designed to examine the impact of almond hull powder (AHP) administration on lipid profile and antioxidant activities in plasma and liver in hyperlipidemic rats. MATERIALS AND METHODS: As the first step, the antioxidant capacity and radical scavenging activity of AHP were determined using calorimetric methods. Then 36 adult male Wistar rats were randomly divided into 6 groups: group 1 with oral administration of 10% AHP, group 2 with oral administration of 20% AHP, group 3 with oral administration of 30% AHP, group 4 as a positive control with a high cholesterol diet, group 5 as a negative control with a normal diet, and group 6 as a sham group with a normal diet and 20% AHP. The rats were fed a hypercholesterolemic diet to create a hyperlipidemia rat model and then they received AHP for 30 days. RESULTS: Antioxidant and radical scavenging activity of the AHP extract showed a high content of antioxidants that exert potent radical scavenging activity. According to the results obtained, upon the administration of AHP the levels of cholesterol and triglycerides significantly decreased, while the antioxidant capacity of plasma increased. CONCLUSION: AHP with bioactive compounds and fiber can reduce total cholesterol and triglycerides and improve serum antioxidant capacity.

Antioxidants in different parts of oleaster as a function of genotype.

INTRODUCTION: Fruits of oleaster (Elaeagnus angustifolia L.) were used in traditional medicine to treat various diseases. The aim of this study was to evaluate and compare the phenol and flavonoid contents and antioxidant activity of methanol extracts from the fruit peel, flesh and seed of seven genotypes of oleaster. METHODS: The phenol and flavonoid contents were determined using spectrophotometric methods. Antioxidant and antiradical activities were determined using reducing power, ferric-reducing antioxidant potential (FRAP) and ability to scavenge DPPH radical assays. RESULTS: Significant differences ( P < 0.05) were found in phenol and flavonoid contents and antioxidant activity among components of fruit and within various genotypes. CONCLUSION: RESULTS indicated that oleaster has good fruit quality varying among different genotypes. Seeds of fruits have excellent antioxidant activity and phenolic contents in comparison to flesh and peel.