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Zucchini (Cucurbita pepo var. cylindrica) were stored at low pressure (4 kPa) at 10°C at 100% relative humidity for 11 days. Fruit quality was examined upon removal and after being transferred to normal atmosphere (101 kPa) at 20°C for three days. Zucchinis stored at low pressure exhibited a 50% reduction in stem-end browning compared with fruit stored at atmospheric pressure (101 kPa) at 10°C. The benefit of low pressure treatment was maintained after the additional three days storage at normal atmospheric pressure at 20°C. Indeed, low pressure treated fruit transferred to regular atmosphere 20°C for three days possessed a significantly lower incidence of postharvest rot compared to fruit stored at regular atmospheric pressure at 10°C. Zucchinis stored at low pressure showed higher levels of acceptability (28% and 36%, respectively) compared to fruit stored at regular atmospheres at 10°C for both assessment times. [ABSTRACT FROM AUTHOR]

Green capsicums (Capsicum annum L.) were stored under low pressure (4 kPa) at 10°C for 5 and 11 days with 100% RH. The results showed that the incidence of stem decay under low-pressure storage for 5 and 11 days and storage at ambient atmosphere at 20°C for 3 days was lower compared to fruits that were stored at regular atmosphere at 10°C. Fruit that had been stored at low pressure at 10°C had no symptoms of flesh rots for up to 11 days, whilst fruit which had been stored at regular atmosphere at 10°C had 6% flesh rots after 11 days storage at 10°C.There was no difference in flesh firmness and colour retention between fruits stored at low pressure and regular pressure at 10°C. Capsicums stored at low pressure had higher overall acceptability compared to fruit that were stored at regular atmosphere at 10°C. These results demonstrate the potential of low pressure storage as an effective technique to manage capsicum fruit quality, however, there was no additional benefit when fruits were stored at low pressure for more than 5 days. [ABSTRACT FROM AUTHOR]

This study aimed to optimise microwave-assisted extraction (MAE) conditions for total phenolic compounds (TPCs) and antioxidant activities of the alga Sargassum vestitum by using response surface methodology with Box-Behnken design. The results showed that solvent concentration had the greatest impact on TPC and antioxidant activities of the extracts, followed by radiation time and power. The optimal MAE conditions were ethanol concentration of 70%, radiation time of 75 s and power of 80%. The optimal MAE method showed much better extraction efficacy of phenolics and antioxidant capacities of the extract than conventional and ultrasonic methods. [ABSTRACT FROM AUTHOR]

Summary: The effect of two lemon by‐product aqueous extracts at different concentrations (14, 7, 3.5 and 1 mg mL−1) was tested against the in vitro growth of Alternaria alternata. Prior to extraction, one batch of by‐product was dehydrated by freeze‐drying (untreated by‐product), while the other batch was treated by microwave irradiation in conjunction with freeze‐drying (microwave‐treated by‐product). High‐performance liquid chromatography (HPLC) was employed for the identification of individual phenolic compounds with potent antifungal activities. Both lemon by‐product aqueous extracts inhibited the mycelial growth and suppressed the spore germination of the fungus in a concentration‐dependent manner. In general, the extracts obtained from the microwave‐treated lemon by‐product displayed enhanced antifungal activity than those obtained from the untreated one. Scanning electron microscopy (SEM) revealed that both lemon by‐product extracts affected the hyphal morphology of the fungus. The antifungal activity of the extracts was attributed to their phenolic acid and ascorbic acid contents. [ABSTRACT FROM AUTHOR]

Abstract: Large quantities of Catharanthus roseus leaf have been used for the extraction of alkaloids, which results in a significant amount of waste that includes the stems, roots, and the extracted leaves. This study aimed to determine the optimal extraction conditions, by applying response surface methodology with Box–Behnken design to assess the interactive effect of ultrasonic parameters, including ultrasonic temperature, time, ratio of sample‐to‐solvent, and ultrasonic power on the extraction efficiency of saponins and antioxidants from the stems of C. roseus. The results revealed that a maximized saponin yield (138.21 mg ESE/g) and strong antioxidant activities (8.34, 12.06, 10.53, and 19.15 mg TE/g for DPPH, ABTS scavenging capacity, FRAP, and CUPRAC, respectively) could be obtained under the optimal extraction conditions: ultrasonic temperature of 55 °C, ultrasonic time of 35 min, sample‐to‐solvent ratio of 1/100 (g/ml), and ultrasonic power of 150 W. Practical applications: Recovering bioactive compounds from Catharanthus roseus stems, especially saponins which have been linked with various biological activities such as antimicrobial, antiherbivore, and/or cytotoxic activities, is necessary to avoid wasting bioresource from the alkaloid exploration of the leaves. This study suggested the optimal ultrasonic conditions that could be used for further extraction and isolation of saponins from C. roseus stems for potential application in the food, nutraceutical, cosmeceutical, and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

The effect of microwave pretreatment on the levels of total phenolic compounds, flavonoids, proanthocyanidins, and individual major compounds as well as the total antioxidant activity of the dried lemon pomace was investigated. The results showed that microwave pretreatment significantly affected all the examined parameters. The total phenolic content, total flavonoids, proanthocyanidins, as well as the total antioxidant activity significantly increased as the microwave radiation time and power increased (e.g., 2.5-fold for phenolics, 1.4-fold for flavonoids, and 5.5-fold for proanthocyanidins); however, irradiation of more than 480 W for 5 min resulted in the decrease of these parameters. These findings indicate that microwave irradiation time and power may enhance higher levels of the phenolic compounds as well as the antioxidant capacity of the dried lemon pomace powder. However, higher and longer irradiation may lead to a degradation of phenolic compounds and lower the antioxidant capacity of the dried lemon pomace. Practical applications Lemon pomace could be a good source of bioactive compounds and antioxidants. Microwave irradiation could be applied for the enhancement of the total phenolic compounds and antioxidants of the lemon pomace-dried powder. The findings of this study can be applied for enhancing the bioactive compounds and the antioxidant activity of the dried lemon pomace for further extraction, isolation, and utilisation. [ABSTRACT FROM AUTHOR]

Hormosira banksii is a rich source of polyphenols, which can be utilized in the food or pharmaceutical industries. This study aimed to determine the impact of six drying methods on properties of the alga H. banksii. Our data revealed that drying conditions significantly affected recovery yield, residual moisture, extraction yield, total phenolic content (TPC) as well as antioxidant capacity of H. banksii ( P < 0.05). Optimal conditions for oven, vacuum and de-humidification were 40, 50 and 50C, respectively, and microwave power is 840 W. Under optimal conditions, H. banksii prepared by freeze, de-humidification and vacuum had significantly higher levels of TPC, total flavonoid content (TFC) and proanthocyanidins as well as possessing stronger antioxidant capacity in comparison with those prepared by sun, microwave and oven drying methods. As freeze drying is costly and time-consuming, de-humidification (50C, air in and out of 11.1 and 15.4%) and vacuum (50C, 10 psi) were recommended for drying H. banksii Practical Applications Algae possess various antioxidants with potential benefits for health. Drying is considered as a method for preserving materials, transport with low costs and especially first step for extraction, isolation and purification of active compounds. Thus, it is important to investigate the effects of drying conditions on the properties of the dried alga H. banksii. From the findings, the different drying conditions significantly affected the phytochemical profile and antioxidant activity of the dried alga and the optimal drying conditions could be applied for preparation of dried H. banksii for further processing (extraction, fractionation and isolation of bioactive compounds) as well as potential industrial applications (as a reference for drying H. banksii and other algae). [ABSTRACT FROM AUTHOR]

The tuckeroo (Cupaniopsis anacardioides) is an Australian native plant that fruits over the summer months. There are very few studies that have characterised its fruit; consequently, this study aimed to delineate the physical, phytochemical and antioxidant properties of the tuckeroo fruit. The tuckeroo skin embodied the largest weight proportion with over 77% of the total fruit weight and it had the highest levels of total phenolic compounds (TPC; 151.36 mg GAE/g), total flavonoids compounds (TFC; 95.94 mg CAE/g), and proanthocyanidins (Proanth; 164.86 mg CAE/g) content, as well as the strongest antioxidant power. The seed and flesh accounted for 23% of the total fruit weight and they possessed significantly lower levels of TPC, TFC and Proanth. This study has demonstrated that the tuckeroo fruit skin is a rich source of phenolic compounds, which can be further isolated and identified for further utilisation in the food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the optimal microwave-assisted extraction (MAE) parameters for saponins and antioxidant capacity from the P. trimera root. The optimal MAE parameters were found to be 100% methanol, extraction time of 40 min and ratio of solvent to sample of 100 mL/g. Saponin content, saponin extraction efficiency, ABTS radical scavenging capacity, DPPH radical scavenging capacity, cupric ion reducing antioxidant capacity, and ferric reducing antioxidant power of the P. trimera root achieved under these parameters were 520.5 mg escin equivalents (EE)/g dried sample, 62.6%, 215.3, 93.2, 24.7, 121.7 mg trolox equivalents (TE)/g dried sample, respectively, which were higher than predicted values (488.8 mg EE/g dried sample, 58.8%, 213.7, 89.5, 24.0, 115.8 mg TE/g dried sample, respectively). Therefore, the optimal MAE parameters of 100% methanol, 40 min and 100 mL/g are recommended for obtaining saponin-enriched extracts from the P. trimera root for potential application in the food industry. Practical Application This study indicated that methanol concentration had the highest effect on the extractability of saponins and antioxidant capacity from P. trimera root, followed by ratio of solvent to sample and extraction time. Therefore, the application of the optimized MAE parameters allows obtaining the highest saponin yield as well as the greatest antioxidant capacity from P. trimera root for further investigation and application. [ABSTRACT FROM AUTHOR]

Different parts of Helicteres hirsuta Lour. ( H. hirsuta L.) have been used as traditional medicines, however limited studies have been conducted on the preparation of dried material or the extraction of bioactive compounds. This study aimed to determine the effect of various solvents and drying methods on the bioactive compound yield and antioxidant capacity of the H. hirsuta L. stem. The results showed that water was the best solvent for obtaining the highest levels of phenolics and flavonoids, whereas methanol was the solvent of choice for saponin extraction. Among assessed drying methods, hot-air drying at 80C revealed as the best method to maintain the bioactive components (phenolics of 8.99 mg GAE/g, flavonoids of 9.60 mg CE/g and saponins of 15.18 mg ESE/g), and DPPH, ABTS, and FRAP antioxidant activities. Thus hot-air drying at 80C is recommended for preparation of dried H. hirsuta L. stem for further processing steps. Practical Applications The optimal drying condition to prepare dried H. hirsuta L. stem is hot-air drying at 80C, a simple and fast drying method, and the most suitable solvent for extraction of antioxidant components from dried H. hirsuta L. stem is water; a cheap, accessible, and environmentally friendly solvent. These conditions can be applied for isolating and purifying bioactive compounds for further application in the food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

This study is designed to develop ultrasonic conditions as an advanced technique for optimal recovery of phenolics and antioxidants fromEucalyptus robustaleaf and to evaluate the impact of solvents, temperature, sonication time and power on ultrasound-assisted extraction of these compounds. Temperature has the greatest impact on the total phenolic content (TPC) yield followed by time and power. A yield of 163.68 ± 2.13 mg GAE/g of TPC is observed using 250 W ultrasonic power for 90 min at 60°C with water. This study validates UAE as an efficient, green, and sustainable technique for extracting phenolics fromE. robusta. [ABSTRACT FROM AUTHOR]

Xao tam phan (Paramignya trimera(Oliv.) Guillaum) has been used as an herbal medicine for the treatment of cancer or cancer-like diseases in recent years, particularly in Vietnam. Drying is an important step for preparation of dried materials for storage and further investigation; however, the effects of drying must be taken into account when processing samples, because this can have profound effects on the stability of phytochemical compounds and the biological activity of the driedP. trimeraroot. As such, this study assessed the effects of four different drying methods (conventional, hot air, vacuum, and microwave) on phytochemical retention and antioxidant capacity ofP. trimeraroot, to identify an optimal drying method forP. trimeraroot. The results showed that the drying methods significantly affected phytochemical levels and antioxidant capacity ofP. trimeraroot and that among the four drying methods tested, microwave drying (400 W) had the highest levels of phytochemical compounds, with total phenolic, total flavonoid, proanthocyanidin, and saponin contents of 11.27 mg GAE, 19.88 mg RE, 3.98 mg CE, and 267.15 mg EE/gram of dried sample, respectively. Dried sample prepared using this method had antioxidant capacity comparable to that of other drying methods. In addition, this method had the shortest drying time (0.28 h) and consumed the least energy (0.28 kWh). Therefore, microwave drying should be considered for dryingP. trimeraroot for further investigation and utilization. [ABSTRACT FROM PUBLISHER]

Vitex agnus-castus (Vitex AC) leaves have been used for medicinal purposes for many years. Drying is important to prepare starting materials for further processing, as it is associated with production cost and quality of the materials. Herein, the effects of five different drying conditions on the physical, chemical and antioxidant properties of Vitex AC were evaluated. The results showed that 30% of dried leaves with moisture content of less than 7% could be produced from fresh leaves. Vitex AC leaves dried by freeze and vacuum drying at 65C had higher levels of bioactive compounds as well as higher antioxidant capacity in comparison with other drying conditions, revealing that these drying conditions are more suitable for drying Vitex AC leaves. However, freeze drying is costly and time-consuming; thus, vacuum drying at 65C is suggested for drying the Vitex AC leaves as the starting materials for further processing steps. [ABSTRACT FROM AUTHOR]

The first reversible molecular brake, which functions at a remote site by the coordination of a metal, is reported. The effect of metal coordination on molecular brake leads to conformational change, which in turn reversibly stops the molecular rotation. Variable temperature 1H NMR experiments prove the operations of the brake.