Effect of sonication, microwaves and high-pressure processing on ACE-inhibitory activity and antioxidant potential of Cheddar cheese during ripening.

Dairy processing provides acceptable safety and shelf-life to final products, and improves their bioactivity. The present study evaluated the potential of different milk processing techniques to improve the antioxidant and angiotensin-I converting enzyme (ACE)-inhibitory activity of Cheddar cheese, during ripening. Cheese was made from milk subjected to different pre-treatments (C = untreated control, US-1 = ultrasonication, specific energy = 23 J/g, 20 kHz frequency; US-2 = Ultrasonication specific energy = 41 J/g, 20 kHz; HPP = high-pressure processing, 400 MPa for 15 min, at temperature < 40 °C; MW = microwave, temperature<40 °C, specific energy = 86.5 J/g) and analysed after ripening for 0, 3, 6 and 9 months. The results showed that the rate of proteolysis during both cheese making and subsequent ripening was significantly affected by the pre-treatment. Antioxidant activity and ACE-inhibitory potential of cheeses made from pre-treated milk significantly increased (p < 0.05) in the following order: US-2 > HPP > US-1 > MW > C. These findings demonstrate the possibility of using ultrasound, microwaves or high-pressure processing as pre-treatments to improve the nutritional attributes of cheese.

Influence of ultrasound on the functional characteristics of indigenous varieties of mango (Mangifera indica L.).

The present study was conducted to evaluate the effect of ultrasonic (US) treatment on chemical characteristics and antioxidant potential of pulps obtained from eight mango varieties indigenous to Pakistan. There was a significant (p < 0.05) effect of varieties and US treatment on chemical characteristics i.e. pH, acidity, TSS, vitamin C contents, total sugars (%), reducing sugars (%) and non-reducing sugars (%). Microstructure evaluation of pulp from all mango varieties showed deshaped middle lamella and cell wall of cells after 8 min of US treatment. At 4 min of US treatment as per shaped cell wall and middle lamella, the chemical characteristics and antioxidant potential were higher. The total phenolics (TP), flavonoids (TF) and total antioxidant activity (TAA) of pulp from most varieties increased significantly (p < 0.05) after US treatment for 4 min but decreased successively after each treatment i.e. 8 and 12 min. The maximum value (314.17 µg AAE/mL pulp) of DPPH was shown by pulp from Dosehri and the minimum (158.67 µg AAE/mL pulp) was found in pulp from Langra before US treatment. The DPPH values of pulp from most of the varieties increased significantly (p < 0.05) after US treatment for 4 min but decreased successively after each treatment but pulp from Langra showed increasing trend after 8 min of US treatment which decreased after 12 min of treatment. The total anthocyanin (TA) values of pulp from Chaunsa, Dosehri, Sindhri, Gulab Khas and Langra increased abruptly after US treatment for 4 min but decreased successively after subsequent treatment. The pulp from Desi, Anwar Ratol, Gulab Khas and Langra showed an abrupt decrease in TA after 8 min of US treatment. An increasing trend of values of total carotenoids (TC) was shown by pulp from all mango varieties after 4 min of US treatment but decreasing trend was observed with subsequent increase in time of US treatment.

Antioxidant potential of a soft cheese (paneer) supplemented with the extracts of date (Phoenix dactylifera L.) cultivars and its whey

Objective: The present study was conducted to evaluate the antioxidant potential of paneer, a soft cheese supplemented with various water soluble date extracts during storage. Further, the whey obtained from all the paneer samples was also investigated for its antioxidant potential. Methods: The date cultivars were evaluated for their physico-chemical characteristics and date extracts were assessed for their antioxidant potential. Physico-chemical evaluation, microbiological quality and further antioxidant potential of the prepared paneer were carried out during storage period (0-8 days, 5°C). Results: All the date extracts were found to have considerable antioxidant activity due to presence of total phenolics and flavonoids. Owing to the presence of phenolics and flavoinds in date extracts, supplemented paneer showed higher trolox equivalent antioxidant capacity, reducing power and DPPH radical scavenging activity than control paneer. Paneer supplemented with Rabi extracts had the highest total phenolics (190.7 µg gallic acid equivalent/g paneer), DPPH radical scavenging activity (928.1 µmol equivalent of Trolx/g paneer) and trolox equivalent antioxidant capacity (9.2 µmol equivalent of Trolx/g paneer). The whey obtained from control paneer showed lower values of total phenolics, total flavonoids, DPPH, trolox equivalent antioxidant capacity and reducing power as compared to the values of whey obtained from paneer supplemented with date extracts. Conclusion: Paneer supplemented with date extracts and its whey may offer potent antioxidant activity.

Natural compounds with xanthine oxidase inhibitory activity: A review.

Hyperuricemia (HUA), a disease due to an elevation of body uric acid level and responsible for various diseases such as gout, cardiovascular disorders, and renal failure, is a major ground debate for the medical science these days. Considering the risk factors linked with allopathic drugs for the treatment of this disease, the debate has now become a special issue. Previously, we critically discussed the role of dietary polyphenols in the treatment of HUA. Besides dietary food plants, many researchers figure out the tremendous effects of medicinal plants-derived phytochemicals against HUA. Keeping in mind all these aspects, we reviewed all possible managerial studies related to HUA through medicinal plants (isolated compounds). In the current review article, we comprehensively discussed various bioactive compounds, chemical structures, and structure-activity relationship with responsible key enzyme xanthine oxidase.

Impact of ultrasound and conventional extraction techniques on bioactive compounds and biological activities of blue butterfly pea flower (Clitoria ternatea L.).

The present study was conducted to evaluate the influence of ultrasound on bioactive compounds and biological activities of blue butterfly pea flower (Clitoria ternatea L.). For this purpose, optimized conditions (temperature 50 °C, time 150 min, solid to liquid ratio 1 g:15 ml, 70% amplitude and 240 W, 20 kHz frequency, 3 s on and 3 s off) of ultrasound (US) and conventional extraction (AGE: Agitation, water bath for 150 min, 50 °C at 150 rmp) were used. The results showed significant (p < 0.05) effect of US and AGE on total phenolics (TPCs), flavonoids (TFCs) and antioxidant activities (DPPH, ABTS, FRAP, reducing activity, Cu2+ and H2O2) of butterfly pea flower extract (BPFE). The results showed an increased trend in yield, TPCs, TFCs and antioxidant activities of US treated BPFE with comparison to AGE. However, insignificant (p > 0.05) effect of US and AGE over TFlaCs and PACs were observed. Moreover, the results of Fourier-transform infrared spectroscopy (FTIR) showed little changes in spectrum and US does not affect the functional group of bioactive compounds structure. Additionally, extracts (500-2000 µg/ml) protect pBR322 plasmid DNA damage induced by (1 mM H2O2 and 1 mM FeSO4), plasma oxidation (induced by 250 µM CuCl2) and inhibit erythrocyte hemolysis (induced by 200 mM AAPH, 34.6 to 66.73%). Sonication can be applied successfully for the extraction of bioactive compounds from plant materials with high biological activities.

Effect of ultrasound and chemical treatment on total phenol, flavonoids and antioxidant properties on carrot-grape juice blend during storage.

Ultrasonics is one of the developing technologies which is being studied extensively on different food commodities. Our aim was to study the effect of sonication and chemical (Potassium metabisulfite, K2S2O5,) preservation method on grape-carrot juice blend. Sonication/ultrasound treatments (20 kHz frequency, 70% amplitude level (525 W power), and pulse duration 5 s on and 5 s off, 5 min at 15 °C) of all the samples (250 mL) were performed by using an ultrasonic processor with 0.5 in. probe at 2 in. depth of the sample. Additionally, impact of sonication on 90 days of storage period at refrigerated temperature was also measured. It was observed that sonication had a positive effect on nutritional status of juice blend as it enhanced the total phenolic, flavonoid, reducing power and antioxidant properties of juice significantly (p < 0.05) with increase in sonication time. Sonication can be employed successfully for treatment of juice with better nutritional attributes from consumers' point of view.