Search Results (17)

Penicillium digitatum and Penicillium italicum are responsible for citrus green and blue moulds (GM and BM), respectively, which are major citrus postharvest diseases. The aim of this study was to develop an optimal dipping mixture of an aqueous solution of different food additives: sodium bicarbonate (SB), sodium benzoate (SBen), and potassium sorbate (PS), in combination with heat, to control GM and BM using response surface methodology. The ranges of SB (0.0%, 3.0%, 6.0%), SBen (0.0%, 0.5%, 1.0%), PS (0.0%, 0.5%, 1.0%) and temperature (20 °C, 35 °C, 50 °C) with a dipping time of 60s were tested for their impact on GM and BM on artificially inoculated oranges. Within these tested ranges, SB reduced GM severity and incidences of both GM and BM. PS affected BM severity and incidence, but not GM. SBen and temperature did not have impact on GM and BM. The most suitable food additive concentrations were identified to be 4.7% SB, 1.0% SBen and 0.7% PS, with a dipping solution temperature of 50 °C. This treatment was shown to reduce GM and BM incidence from 85 and 86% on control fruit dipped in tap water at 20 °C to 3 and 10%, respectively. Additionally, the severity of GM and BM was reduced from 64 and 26 mm on control fruit to <1 and 2.8 mm, respectively. Full article

Herbal teas, which are a rich and diverse source of polyphenols, have been widely consumed due to their association with various health benefits. Preparation techniques can significantly affect the level of polyphenols in a cup of tea. Thus, this study investigated the impact of different preparation techniques, including brewing time in hot water, microwave-assisted extraction with cold and hot water (cold and hot MAE) for both radiation time and power, and laboratory testing condition on extractability of polyphenols in infusion from a teabag. The results showed that brewing time using hot water significantly affected the extractability of polyphenols and antioxidant activity. Cold and hot MAE conditions also significantly affected the extractability of polyphenols and antioxidant activity from a teabag infusion. Hot brewing at 7 min and cold MAE at full power with second boiled (1.93 min on and 1 min off radiation) are recommended for the preparation of herbal tea from a teabag, as these conditions had comparable extractability of polyphenols and antioxidant activity in comparison with other preparation techniques. There are over 20 major chromatogram peaks, of which 7 were identified as gallic acid, catechin, caffeic acid, ferulic acid, epicatechin gallate, quercetin, and kaempferol, revealing potential health benefits of this herbal tea. Full article

Cannabis is well-known for its numerous therapeutic activities, as demonstrated in pre-clinical and clinical studies primarily due to its bioactive compounds. The Cannabis industry is rapidly growing; therefore, product development and extraction methods have become crucial aspects of Cannabis research. The evaluation of the current extraction methods implemented in the Cannabis industry and scientific literature to produce consistent, reliable, and potent medicinal Cannabis extracts is prudent. Furthermore, these processes must be subjected to higher levels of scientific stringency, as Cannabis has been increasingly used for various ailments, and the Cannabis industry is receiving acceptance in different countries. We comprehensively analysed the current literature and drew a critical summary of the extraction methods implemented thus far to recover bioactive compounds from medicinal Cannabis. Moreover, this review outlines the major bioactive compounds in Cannabis, discusses critical factors affecting extraction yields, and proposes future considerations for the effective extraction of bioactive compounds from Cannabis. Overall, research on medicinal marijuana is limited, with most reports on the industrial hemp variety of Cannabis or pure isolates. We also propose the development of sustainable Cannabis extraction methods through the implementation of mathematical prediction models in future studies. Full article

Penicillium digitatum and P. italicum are the major postharvest pathogens in citrus. To reduce postharvest decay, the use of low-oxygen (0.9 kPa O₂) (LO) or low-pressure (6.6 kPa) (LP) treatments were evaluated during the storage of navel oranges for four or eight days. The results showed that exposure to both LO and LP treatments reduced in vivo pathogen growth compared to the untreated (UTC) oranges, with LO being the most effective. The effects of LO and LP on fruit metabolism and quality were further assessed, and it was found that there was no effect on fruit ethylene production, respiration rate, TSS (total soluble solids), TA (titratable acidity) or fruit firmness. However, both LO and LP treatments did have an effect on juice ethanol concentration and fruit weight-loss. The effect of adding exogenous ethylene at either LP (1 µL/L) or atmospheric pressure (AP) (at either 0.1, 1 µL/L) was also evaluated, and results showed that the addition of ethylene at these concentrations had no effect on mould diameter at LP or AP. Therefore, both LO of 0.9 kPa O₂ and LP of 6.6 kPa at 20 °C are potential non-chemical postharvest treatments to reduce mould development during storage with minimal effects on fruit quality. Full article

Bioactive glasses 70SiO₂–(30-x)CaO–xZnO (x = 1, 3, 5 mol.%) were prepared by the acid-free hydrothermal method in keeping with green chemical technology. The synthetic glasses were investigated by TG-DSC, BET, XRD, and SEM–EDX methods. All synthetic glasses present mesoporous structures consisting of aggregates of nanoparticles. The bioactivity of synthetic glasses was confirmed through the formation of the hydroxyapatite phase after an in vitro experiment in simulated body fluid (SBF) solution. The effect of Zn addition is shown through the decrease in the bioactivity of synthetic glasses. Additionally, the inductively coupled plasma optical emission spectrometry (ICP-OES) analysis indicates that the Zn ions were released from the glassy networks during in vitro experiments, and they act as Zn(OH)₂ suspended precipitation to inhibit the apatite deposition. The in vitro experiment in cell culture matter was performed for SaOS₂ and Eahy929 cells. The results confirm the biocompatibility of synthetic glasses and the role of Zn addition in the proliferation of living cells. Full article

Tuckeroo (Cupaniopsis anacardioides) is an Australian native tree, possessing high level bioactivity and antioxidant activity. To prevent deterioration of active constituents, appropriate drying practices must be determined. This study comparatively evaluates the impact of a range of drying methods including freeze-, microwave-, vacuum-, hot air- and sun-drying on the physical, phytochemical and antioxidant characteristics of Tuckeroo fruit. Experimental results showed that the five drying methods had significant impact on the physicochemical properties and antioxidant activity of the fruits. Of the drying methods assessed, freeze drying best preserved Tuckeroo activity, recording higher total phenolic content (TPC) (81.88 mg gallic acid equivalent (GAE)/g), total flavonoids (TFC) (107.71 mg catechin equivalent (CAE)/g), proanthocyanidins (TPro) (83.86 mg CAE/g) and exhibited the strongest antioxidant capacity. However, vacuum drying at 65 kPa, 100 °C for 5 h is recommended for drying Tuckeroo fruits for further processing in a large scale as it also retained high levels of TPC, TFC and TPro (58 mg GAE/g, 91 mg CAE/g and 74 mg CAE/g, respectively). Full article

Mangiferin has been reported to exhibit anti-viral, anti-cancer, anti-diabetic, immunomodulatory and hepatoprotective properties. This study aimed to develop an HPLC method to isolate mangiferin from Salacia chinensis L. root; investigate the impact of solvents on yield; optimise the ultrasound-assisted extraction (UAE) technique; and compare mangiferin yield with continuously shaking extraction (CSE) and decoction techniques. The results showed that mangiferin, with a purity of over 88%, could be achieved by HPLC using a mixture of solvent A (water: acetonitrile: orthophosphoric acid, 96.8:3:0.2 (v/v/v)) and solvent B (acetonitrile). Solvent type significantly affected the extraction yield of mangiferin, and a mixture of acetone and water gave the highest extraction yield, as compared to other solvents or mixtures. UAE conditions, such as ultrasonic power, temperature, time and concentration of acetone significantly affected the extraction of mangiferin. Optimal UAE conditions were at an ultrasonic power of 250 W, temperature of 50 °C, acetone concentration of 40% and extraction time of 60 min. These optimal conditions could extract approximately 92 mg, whereas CSE and decoction only extracted 89.20 mg and 58.71 mg of mangiferin, respectively, from 1 g of S. chinensis root. Therefore, these UAE conditions are recommended for the extraction of mangiferin from S. chinensis root for further utilisation. Full article

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. Full article

Several studies have shown that UV-C (ultraviolet C) irradiation promotes the bioactive compounds and antioxidants of fresh fruits and vegetables. The aim of this study was to apply UV irradiation in dried lemon pomace powder for enhancing its phenolic content and antioxidant properties, thus more bioactive compounds should be available for extraction and utilization. Lemon pomace dried powder was placed under a UV lamp and treated with dosages of 4, 19, 80 and 185 kJ·m⁻², while untreated powder was used as a control. UV-C irradiation significantly affected the total phenolic content, total flavonoid content, proanthocyanidins, and antioxidant capacity measured by cupric reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP) of the lemon pomace dried powder, while it did not affect the vitamin C content. UV-C irradiation of 19 kJ·m⁻² resulted in 19% higher total phenolic content than the control, while UV-C irradiation of 180 kJ·m⁻² resulted in 28% higher total flavonoid content than the control. The antioxidant capacity was reduced when UV-C irradiation more than 4 kJ·m⁻² was applied. The results of this study indicate that UV-C treatment has the potential to increase the extraction of bioactive compounds of dried lemon pomace at relatively high dosages. Full article

This study aimed to develop optimal microwave assisted extraction conditions for recovery of phenolic compounds and antioxidant properties from the macadamia skin, an abundant waste source from the macadamia industry. Water, a safe, accessible, and inexpensive solvent, was used as the extraction solvent and Response Surface Methodology (RSM) was applied to design and analyse the conditions for microwave-assisted extraction (MAE). The results showed that RSM models were reliable for the prediction of extraction of phenolic compounds and antioxidant properties. Within the tested ranges, MAE radiation time and power, as well as the sample-to-solvent ratio, affected the extraction efficiency of phenolic compounds, flavonoids, proanthocyanidins, and antioxidant properties of the macadamia skin; however, the impact of these variables was varied. The optimal MAE conditions for maximum recovery of TPC, flavonoids, proanthocyanidins and antioxidant properties from the macadamia skin were MAE time of 4.5 min, power of 30% (360 W) and sample-to-water ratio of 5 g/100 mL. Under these conditions, an extract could be prepared with TPC of 45 mg/g, flavonoids of 29 mg RUE/g of dried macadamia skin. Full article

The moisture sorption isotherm of pea starch films prepared with various glycerol contents as plasticizer was investigated at different storage relative humidities (11%–96% RH) and at 5 ± 1, 15 ± 1, 25 ± 1 and 40 ± 1 °C by using gravimetric method. The results showed that the equilibrium moisture content of all films increased substantially above a_w = 0.6. Films plasticized with glycerol, under all temperatures and RH conditions (11%–96%), adsorbed more moisture resulting in higher equilibrium moisture contents. Reduction of the temperature enhanced the equilibrium moisture content and monolayer water of the films. The obtained experimental data were fitted to different models including two-parameter equations (Oswin, Henderson, Brunauer–Emmitt–Teller (BET), Flory–Huggins, and Iglesias–Chirife), three-parameter equations Guggenhiem–Anderson–deBoer (GAB), Ferro–Fontan, and Lewicki) and a four-parameter equation (Peleg). The three-parameter Lewicki model was found to be the best-fitted model for representing the experimental data within the studied temperatures and whole range of relative humidities (11%–98%). Addition of glycerol increased the net isosteric heat of moisture sorption of pea starch film. The results provide important information with estimating of stability and functional characteristics of the films in various environments. Full article

Thousands of tons of macadamia skin waste are generated annually with very limited utilisation of this extensive by-product. The aim of this study was to develop optimal ultrasonic extraction conditions for maximized recovery of phenolic compounds and antioxidant properties from macadamia skin using Response Surface Methodology (RSM). Three ultrasonic parameters, including temperature (30–50 °C), time (10–50 min) and power (150–250 W), were tested for their impact on the extraction of total phenolic compounds (TPC), flavonoids, proanthocyanidins and antioxidant properties. The results showed that ultrasonic temperature, time and power had an impact on TPC and antioxidant capacity; however, the effects varied. The optimum ultrasonic conditions for the maximum recovery of phenolic compounds and antioxidant properties from macadamia skin were found to be a temperature of 40 °C, a time of 35 min and a power of 80%/200 W. Under these optimal conditions, approximately 168 mg of TPC, 135 mg of flavonoids and 188 mg of proanthocyanidins can be extracted from one gram of dried macadamia skin. Full article

The macadamia is native to Australia and is now grown commercially around the world. Macadamia skin, known as waste, has been generated abundantly, but this ample source has had limited uses as a byproduct. The aim of this study was to develop optimal aqueous extraction conditions for the recovery of phenolic compounds and antioxidant properties from macadamia skin using Response Surface Methodology (RSM). Water was selected for optimizing the extraction conditions because it is a cheap, safe, and environmentally friendly solvent. The results showed that the RSM models were reliable for the prediction and evaluation of the tested variables. Within the tested ranges, temperature (°C), time (min), and sample-to-solvent ratio (g/100 mL), and their interactions, did not significantly affect phenolic compound (TPC), flavonoid, proanthocyanidin, CUPRAC, and FRAP contents. However, the time and the sample-to-solvent ratio significantly affected DPPH antioxidant activity and the ratio significantly affected ABTS antioxidant capacity. The optimal extraction conditions for the recovery of phenolic compounds and antioxidant properties were predicted and validated at a temperature of 90 °C, a time of 20 min, and a sample-to-solvent ratio of 5 g/100 mL. At these conditions, an extract with TPC of 86 mg GAE/g, flavonoids of 30 mg RUE/g, and proanthocyanidins of 97 mg CAE/g could be prepared with potent antioxidant capacity. Full article

Euphorbia tirucalli is a succulent shrub or small tree that is native to the African continent, however, it is widely cultivated across the globe due to its use in traditional medicines to treat ailments, ranging from scorpion stings to HIV. Recent studies have identified compounds present in the latex of the plant, including a range of bi- and triterpenoids that exhibit bioactivity, including anticancer activity. This study aimed to optimize water extraction conditions for high-yield total phenolic content recovery, to prepare methanol and aqueous extracts from the aerial sections of the plant, and to test the phytochemical, antioxidant, and anti-cancer properties of these extracts. Water extraction of total phenolic compounds (TPC) was optimized across a range of parameters including temperature, extraction time, and plant mass-to-solvent ratio. The water extract of the E. tirucalli powder was found to contain TPC of 34.01 mg GAE (gallic acid equivalents)/g, which was approximately half that of the methanol extract (77.33 mg GAE/g). The results of antioxidant assays showed a uniform trend, with the methanol extract’s antioxidant reducing activity exceeding that of water extracts, typically by a factor of 2:1. Regression analysis of the antioxidant assays showed the strongest correlation between extract TPC and antioxidant activity for the ABTS (2,2-azino-bis(3-ethyl-benzothiazoline-6-sulfonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl) methods. The methanol extract also showed greater growth inhibition capacity towards the MiaPaCa-2 pancreatic cancer cell line. These data suggest that further investigations are required to confirm the source of activity within the E. tirucalli leaf and stems for potential use in the nutraceutical and pharmaceutical industries. Full article

Olea europaea L. leaves are an agricultural waste product with a high concentration of phenolic compounds; especially oleuropein. Oleuropein has been shown to exhibit anti-proliferative activity against a number of cancer types. However, they have not been tested against pancreatic cancer, the fifth leading cause of cancer related death in Western countries. Therefore, water, 50% ethanol and 50% methanol extracts of Corregiola and Frantoio variety Olea europaea L. leaves were investigated for their total phenolic compounds, total flavonoids and oleuropein content, antioxidant capacity and anti-proliferative activity against MiaPaCa-2 pancreatic cancer cells. The extracts only had slight differences in their phytochemical properties, and at 100 and 200 μg/mL, all decreased the viability of the pancreatic cancer cells relative to controls. At 50 μg/mL, the water extract from the Corregiola leaves exhibited the highest anti-proliferative activity with the effect possibly due to early eluting HPLC peaks. For this reason, olive leaf extracts warrant further investigation into their potential anti-pancreatic cancer benefits. Full article