Extraction Optimization of Phenolics and Antioxidants from Black Goji Berry by Accelerated Solvent Extractor Using Response Surface Methodology

Encapsulation and antibacterial studies of goji berry and garlic extract in the biodegradable chitosan

As known, the chitosan is a biodegradable biopolymer with antibacterial properties, therefore it is used in the fields of pharmacy, medical, wastewater treatment, biotechnology, cosmetics, textiles, and agriculture. Apart from these, the chitosan has an important place in the food industry with its widespread use. In this research article, the chitosan were encapsulated with the taurine and garlic extracts by the spray dryer. The CSA and CSB compounds synthesized as final products were analyzed by Fourier transformed infrared spectroscopy (FTIR) and High Performance Liquid Chromatography (HPLC). The effect of the encapsulation process on the molecular weight of the polymer structure was investigated using the cryoscopy method. The compound CSA represents 1/2 encapsulation of chitosan with taurine and increased garlic extracts, respectively, while CSB represents 1/1 encapsulation of chitosan with increased taurine and fixed garlic extracts. The % antioxidant activity of the final products was determined by DDPH method. The inhibition zone and surface activity proporties of the CSA and CSB were carried out against Listeria monocytogenes, Staphylococcus aureus, E. coli, and Salmonella bacteria. The results obtained as a result of the analyzes were evaluated, and optimum values were determined for use in food packaging.

Effect of hot water, ultrasound, microwave, and pectinase-assisted extraction of anthocyanins from black goji berry for food application

Lycium ruthenicum, commonly known as black goji berry, is a rich anthocyanin source containing a high amount of monoacylated anthocyanins. This study investigates the effect of different extraction methods to extract anthocyanins from black goji berry for food application. Different hot water extraction conditions were applied to investigate the effect of specific substrate: solvent ratio (1:15 and 1:20 (w/v)), extraction time (30 and 60 min) and extraction temperature (40, 50 and 60 °C) on the extraction yield, total anthocyanin content (TAC) and the total phenolic content (TPC) of the anthocyanin extracts. Best hot water extraction conditions for obtaining an anthocyanin extract with high TAC (13.8 ± 1.14 mg CGE/g), TPC (69.7 ± 2.50 mg of GAE/g), and extraction yield (48.3 ± 3.25%) consuming less solvent, time and heat were substrate: solvent ratio of 1: 15 (w/v), extraction temperature of 50 °C, and extraction time of 30 min. The effect of pectinase, ultrasound, and microwave on hot water extraction of anthocyanins from black goji berry was investigated using the best conditions for hot water extraction. Pectinase-assisted extraction [1.5% (w/v) pectinase, substrate: solvent ratio of 1:15 (w/v) at 50 °C for 30 min] was the best extraction method to extract black goji berry anthocyanins demonstrating higher extraction yield, TAC, TPC, and the highest percentage of petunidin-3-O-(trans-p-coumaroyl)-rutinoside-5-O-glucoside.

Distinct Role of Lycium barbarum L. Polysaccharides in Oxidative Stress-Related Ocular Diseases

Oxidative stress is an imbalance between the increased production of reactive species and reduced antioxidant activity, which can cause a variety of disturbances including ocular diseases. Lycium barbarum polysaccharides (LBPs) are complex polysaccharides isolated from the fruit of L. barbarum, showing distinct roles in antioxidants. Moreover, it is relatively safe and non-toxic. In recent years, the antioxidant activities of LBPs have attracted remarkable attention. In order to illustrate its significance and underlying therapeutic value for vision, we comprehensively review the recent progress on the antioxidant mechanisms of LBP and its potential applications in ocular diseases, including diabetic retinopathy, hypertensive neuroretinopathy, age-related macular degeneration, retinitis pigmentosa, retinal ischemia/reperfusion injury, glaucoma, dry eye syndrome, and diabetic cataract.

An Integrated Approach for the Valorization of Sea Bass (Dicentrarchus labrax) Side Streams: Evaluation of Contaminants and Development of Antioxidant Protein Extracts by Pressurized Liquid Extraction

In this study, the presence of As, Hg, Cd, Pb, and mycotoxins in sea bass side streams (muscle, head, viscera, skin, and tailfin) was evaluated as a preliminary step to assess the effect of an innovative extraction technique (Pressurized Liquid Extraction; PLE) to obtain antioxidant protein extracts. Then, a response surface methodology-central composite design was used to evaluate and optimize the PLE extraction factors (pH, temperature, and extraction time) in terms of total protein content and total antioxidant capacity (TEAC and ORAC). Heavy metals were found in all samples while DON mycotoxin only in viscera, both far below the safe limits established by authorities for fish muscle tissue and fish feed, respectively. The selected optimal PLE extraction conditions were pH 7, 20 °C, 5 min for muscle, pH 4, 60 °C, 15 min for heads, pH 7, 50 °C, 15 min for viscera, pH 7, 55 °C, 5 min for skin, and pH 7, 60 °C, 15 min for tailfins. Optimal PLE conditions allowed increasing protein content (1.2-4.5 fold) and antioxidant capacity (1-5 fold) of sea bass side stream extracts compared to controls (conventional extraction). The highest amount of protein was extracted from muscle while the highest protein recovery percentage was found in viscera. Muscle, head, and viscera extracts showed higher antioxidant capacity than skin and tailfin extracts. Moreover, different SDS-PAGE patterns were observed among samples and a greater quantity of protein fragments of lower molecular weight were found in optimal than control extracts.

The Role of Oxidative Stress and Natural Antioxidants in Ovarian Aging

The ovarian system comprises vital organs in females and is of great significance for the maintenance of reproductive potential and endocrine stability. Although complex pathogenesis undoubtedly contributes to ovarian aging, increasing attention is being paid to the extensive influence of oxidative stress. However, the role of oxidative stress in ovarian aging is yet to be fully elucidated. Exploring oxidative stress-related processes might be a promising strategy against ovarian aging. In this review, compelling evidence is shown that oxidative stress plays a role in the etiology of ovarian aging and promotes the development of other ovarian aging-related etiologies, including telomere shortening, mitochondrial dysfunction, apoptosis, and inflammation. In addition, some natural antioxidants such as quercetin, resveratrol, and curcumin have a protective role in the ovaries through multiple mechanisms. These findings raise the prospect of oxidative stress modulator-natural antioxidants as therapeutic interventions for delaying ovarian aging.

Effects of treatment temperatures on redox potential and sensory evaluation of different spices and herbs applied to cooked pork sausages

BACKGROUND

This study aimed to investigate the effects of treatment temperatures (22, 78, 100 °C) on the antioxidant activity of 13 types of dried ground spices and herbs (black mustard, black pepper, blackberries, onion, cumin, galangal, lemon balm, lovage, marjoram, oregano, parsley, rosemary and watercress) through measurements of redox potential. Four different combinations of spices and herbs were created and applied to cooked pork sausages, then sensory evaluation was carried out.

RESULTS

The redox potential was temperature dependent. A temperature of 78 °C was chosen to produce the cooked pork sausages with the addition of the spice and herb combinations. The combinations were black mustard, onion, and cumin (at a 1:1:1 ratio); onion, marjoram, and parsley (at a 1:1:1 ratio); black pepper, lemon balm, and parsley (at a 1:2.35:1.65 ratio) and black pepper, cumin, and lovage (at a 1:2:2 ratio). In pork sausages cooked at 78 °C, the variants at 12 g kg^-1 had a more intense aroma and taste than those at 6 g kg^-1 spice and herb combinations, and received a superior sensory evaluation in total.

CONCLUSIONS

The most desirable treatment temperature possibly applied in food products was 78 °C as it gave the highest number of negative results in redox potential of water extracts. The addition of the tested spice and herb combinations contributed to the increase of antioxidant possibility of 78 °C-cooked pork sausages. Further investigation of the redox potential in other meat products (raw meat products at 22 °C, sausages from cooked meat at 100 °C) with the addition of the current spice and herb combinations will be undertaken in subsequent research. © 2020 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Developing deep learning based regression approaches for determination of chemical compositions in dry black goji berries (Lycium ruthenicum Murr.) using near-infrared hyperspectral imaging

Black goji berry (Lycium ruthenicum Murr.) has great commercial and nutritional values. Near-infrared hyperspectral imaging (NIR-HSI) was used to determine total phenolics, total flavonoids and total anthocyanins in dry black goji berries. Convolutional neural networks (CNN) were designed and developed to predict the chemical compositions. These CNN models and deep autoencoder were used as supervised and unsupervised feature extraction methods, respectively. Partial least squares (PLS) and least-squares support vector machine (LS-SVM) as modelling methods, successive projections algorithm and competitive adaptive reweighted sampling (CARS) as wavelength selection methods, and principal component analysis (PCA) and wavelet transform (WT) as feature extraction methods were studied as conventional approaches for comparison. Deep learning approaches as modelling methods and feature extraction methods obtained good and equivalent performances to the conventional methods. The results illustrated that deep learning had great potential as modelling and feature extraction methods for chemical compositions determination in NIR-HSI.

Effect of lipophilic sea buckthorn extract on cream cheese properties

The aim of this study was to evaluate the physico-chemical, microbiological, sensory properties and antioxidant activity of the functional cream cheese prepared with lipophilic extracts of sea buckthorn (Hippophae rhamnoides L.). The first step of the research consisted of an evaluation of the physico-chemical characteristics and the antioxidant capacity of the sea buckthorn lipophilic extracts. The sea buckthorn extracts had a significant antioxidant capacity (67.04 ± 2.67%), a content of total carotenoids of 8.27 ± 0.01 mg L-1 and a content of total polyphenols of 1842.86 ± 1.41 mg/100 g dry vegetal material. The addition of the sea buckthorn extracts did not negatively affect the fresh cream cheese's sensory characteristics. The addition of sea buckthorn extracts to the cream cheese resulted in an increase of antiradical activity and dry matter content, a decrease in acidity and higher growth inhibitition of germs.

Characterization of Polyphenolic Compounds Extracted from Different Varieties of Almond Hulls (Prunus dulcis L.)

Ultrasound-assisted extraction (UAE) was applied as a pretreatment technique to improve the recovery of polyphenols from the almond hulls of four Tunisian and three Italian almond varieties, followed by the characterization with HPLC-DAD. The operating parameters (solid/liquid ratio, extraction time, and ethanol concentrations) were optimized using a Response Surface Methodology. A polynomial equation was calculated to describe the relationship between the operating parameters and dependent variables as total polyphenolic content (TPC) and antioxidant activity (RSA). A desirability function approach was used to determine the optimum conditions for operating parameters: a solid:solvent ratio of 2 g/100 mL, an extraction time of 13 min, and an ethanol concentration of 51.2%. Among the almond varieties, Pizzuta and Fakhfekh showed the highest polyphenol content and antioxidant activity. HPLC-DAD analysis of almond hull extracts confirmed that chlorogenic acid, catechin, and protocatechuic acid were the most important polyphenols in almond hull. The results highlighted that UAE could be an effective technique for the recovery of phenolic compounds from almond hull, thereby making this byproduct a promising source of compounds with potential applications in food and healthcare sectors.

Power Transformer’s Electrostatic Ring Optimization Based on ANSYS Parametric Design Language and Response Surface Methodology

In this paper, in view of the low efficiency of the traditional finite element method (FEM), which has been widely used in the insulation design of power transformers, the response surface methodology (RSM) is proposed to optimize the insulation structure of a power transformer electrostatic ring. Firstly, the power transformer model was built using the ANSYS parametric design language (APDL) to realize the automatic pre-processing of numerical calculation. Then with the objective of reducing the maximum electric field intensity, the Taguchi method was used to select the parameters that have a greater impact on the maximum electric field intensity, by which the subsequent optimization process could be effectively simplified. The test points were constructed by the central composite design (CCD) and a response surface model was established by the mutual calls of MATLAB and ANSYS. Finally, the variance analysis, diagnostic analysis, and significance test of regression were carried out to obtain the final response surface model. By comparing the result of RSM with that of FEM, we can find that the results obtained by the two methods are consistent and the maximum electric field strength is obviously reduced. The RSM is more systematic and convincing, which improves the optimization efficiency and provides a reliable and fast way for the optimization of power transformers.

Rapid Solid-Liquid Dynamic Extraction (RSLDE): A Powerful and Greener Alternative to the Latest Solid-Liquid Extraction Techniques

Traditionally, solid-liquid extractions are performed using organic and/or inorganic liquids and their mixtures as extractant solvents in contact with an insoluble solid matrix (e.g., the Soxhlet method) or using sequential atmospheric pressure systems that require long procedures, such as maceration or percolation. The objective of this procedure is the extraction of any compounds that can be carried out from the inner solid material to the outlet, resulting in a solution containing colorants, bioactive compounds, odorous substances, etc. Over the years, in the extraction techniques sector, there have been many important changes from the points of view of production, quality, and human and environmental safety due to improvements in technology. In more recent times, the interest of the scientific community has been aimed at the study of sustainable processes for the valorization of extracts from vegetables and food by-products, through the use of non-conventional (innovative) technologies that represent a valid alternative to conventional methods, generally through saving time and energy and the formation of fewer by-products. Therefore, with the development of principles based on the prevention of pollution, on a lower risk for human health, and on a low environmental impact, new systems have been implemented to reduce extraction times and solvent consumption, to improve efficiency, and to increase the productivity of the extracts. From this point of view, rapid solid-liquid dynamic extraction (RSLDE), performed using the Naviglio extractor, compared to traditional applications, is a technique that is able to reduce extraction times, generally leads to higher yields, does not require heating of the system, allows one to extract the active ingredients, and avoids their degradation. This technique is based on a new solid-liquid extraction principle named Naviglio’s principle. In this review, after reviewing the latest extraction techniques, an overview of RSLDE applications in various research and production sectors over the past two decades is provided.

Assessment of Ultrasound Assisted Extraction as an Alternative Method for the Extraction of Anthocyanins and Total Phenolic Compounds from Maqui Berries (Aristotelia chilensis (Mol.) Stuntz)

Research interest regarding maqui (Aristotelia chilensis) has increased over the last years due to its potential health benefits as one of the most antioxidant-rich berries. Ultrasound-assisted extraction (UAE) is an advanced green, fast, and ecological extraction technique for the production of high quality extracts from natural products, so it has been proposed in this work as an ideal alternative extraction technique for obtaining extracts of high bioactivity from maqui berries. In order to determine the optimal conditions, the extraction variables (percentage of methanol, pH, temperature, ratio “sample mass/volume of solvent”, amplitude, and cycle) were analyzed by a Box-Behnken design, in conjunction with the response surface method. The statistical analysis revealed that the temperature and the percentage of methanol were the most influential variables on the extraction of the total phenolic compounds and total anthocyanins, respectively. The optimal extraction time was determined at 15 min for total phenolic compounds, while it was only 5 min for anthocyanins. The developed methods showed a high precision level with a coefficient of variation of less than 5%. Finally, the new methods were successfully applied to several real samples. Subsequently, the results were compared to those that were obtained in previous experiments by means of microwave assisted extraction (MAE). Similar extraction yields were obtained for phenolic compounds under optimized conditions. However, UAE proved to be slightly more efficient than MAE in the extraction of anthocyanins.