Optimization of microwave assisted extraction of pectin from orange peel

Development of microencapsulated grape juice powders using black 'Isabel' grape peel pectin and application in jelly formulation with enhanced in vitro bioaccessibility of anthocyanins

In this study, pigmented pectin (grape pectin, GP) was extracted from the peels of black Isabel grapes. This highly methoxylated GP was composed mainly of galacturonic acid, arabinose, and other neutral monosaccharides. Its red color was ascribed to the anthocyanin content, and the main contribution was from malvidin-3-O-glucoside. To improve the yield and color properties of spray-dried Isabel grape juice powders, maltodextrin (MD) was substituted with this colored GP. When 25% of MD was substituted with GP, the powder yield increased from 46.0% to 60.4%, but it decreased to 21% when the substitution was 40%. GP inclusion increased the encapsulation efficiency of total anthocyanin in powders from 55.70% to 88.66%. When this spray-dried grape juice powder containing GP was utilized in a jelly recipe (4%-10%), a higher level of inclusion yielded stronger and more brittle jellies. When the jellies containing varying amounts of GP were subjected to in vitro digestion, the formulation with a higher amount of GP yielded a higher recovery of anthocyanins. In addition to being utilized as a carrier agent for spray-drying applications, this pigmented GP can also be tailored for a variety of applications, such as the development of pH-sensitive edible films and functional beverage formulations.

Biochemical Composition, Antioxidant Capacity and Protective Effects of Three Fermented Plants Beverages on Hepatotoxicity and Nephrotoxicity Induced by Carbon Tetrachloride in Mice

Functional beverages play an essential role in our modern life and contribute to nutritional well-being. Current efforts to understand and develop functional beverages to promote health and wellness have been enhanced. The present study aimed to investigate the production of three fermented plants beverages (FPBs) from aromatic and medicinal plants and to evaluate the fermented product in terms of physio-biochemical composition, the aromatic compounds, antioxidant activity, and in vivo protective effects on hepatotoxicity and nephrotoxicity induced by carbon tetrachloride (CCl4). The results showed that the fermented beverage NurtBio B had the highest levels of polyphenols, flavonoids, and tannins; 242.3 ± 12.4 µg GAE/mL, 106.4 ± 7.3 µg RE/mL and 94.2 ± 5.1 µg CE/mL, respectively. The aromatic profiles of the fermented beverages showed thirty-one interesting volatile compounds detected by GC-MS headspace analyses such as benzaldehyde, Eucalyptol, Fenchone, 3-Octadecyne, Estragole, and Benzene propanoic acid 1-methylethyl ester. In addition, the fermentation process was significantly improved, indicating its great potential as a functional food with both strong antioxidant activity and good flavor. In vivo administration of CCl4 in mice induced hepatotoxicity and nephrotoxicity by a significant rise in the levels of serum liver and kidney biomarkers. The protective effects of the FPBs showed that they significantly restored the majority of these biological parameters to normal levels, along with increase antioxidant enzyme activities, as well as an improvement of histopathological changes, suggesting their protective effects.

Environmentally Friendly Approach to Pectin Extraction from Grapefruit Peel: Microwave-Assisted High-Pressure CO2/H2O

In this research, pectin extraction from grapefruit peel (GPP) was performed using a microwave-assisted high-pressure CO2/H2O (MW-HPCO2) system. The Box-Behnken design of response surface methodology was applied for the optimization of MW-HPCO2 extraction conditions to obtain the highest pectin yield. The effects of temperature, time, and liquid/solid ratio on pectin yield were examined in the range of 100-150 °C, 5-15 min, and 10-20 mL g-1, respectively. Under the optimum extraction conditions (147 °C, 3 min, and 10 mL g-1), pectin was obtained with a yield of 27.53%. The results obtained showed that the extraction temperature and time had a strong effect on the pectin yield, while the effect of the liquid/solid ratio was not significant, and the pectin was effectively extracted from grapefruit peel (GP) using MW-HPCO2. Additionally, the application of GPP in apricot jam showed that MW-HPCO2-GPP can be used as a thickener in the food industry. The yield and physicochemical properties (ash, protein, galacturonic acid, reducing sugar and methoxyl content, degree of esterification, equivalent weight, color, viscosity) of pectin extracted in the optimum conditions of the MW-HPCO2 method were superior to pectin extracted by the traditional method. The results of this study revealed that MW-HPCO2 could be an innovative green and rapid technique for pectin extraction.

Moroccan Citrus clementina Peels: Optimization of Pectin Extraction and Determination of Chemical and Functional Properties

Citrus peels are considered a rich source of valuable biomolecules. Pectin is a polymer of polysaccharide acid and is composed of galacturonic acid monosaccharides. In this study, response surface methodology was used to optimize pectin extraction from Citrus × clementina Hort. ex Tan. (Rutaceae) peels using citric acid as an extraction solvent. The effect of the parameters conditioning the extraction process and pectin yield (pH level, temperature, extraction time, solid/liquid ratio, and raw material particle size) was investigated using a Box-Behnken design. The quality of the extracted pectin was assessed both chemically (moisture, ash, protein, and carbohydrate content) and functionally (gelling power and emulsifying activity). According to the screening experiment, the pH level, temperature, and particle size were the main factors influencing the pectin yield. The adjusted mathematical model enabled us to plot response surfaces in order to determine the optimal extraction conditions. The highest production yield of pectin (26.6%) was obtained at the optimal conditions of pH = 1.5, temperature = 100 °C, and particle size = 0.1 mm for an extraction time of 30 min. Compared to the predicted value of 26.6%, the experimental extraction yield of C. clementina was about 21.4% of pectin. Concerning the functional properties, the extracted pectin had a high gelling power of 164 ° SAG and an emulsifying activity of 38.5%.

Optimization of LDO-Pectin Synthesis Conditions for the Removal of Metals from Wastewater: A Comparison of Response Surface Methods and Taguchi Approaches

With the continuous growth of industrialization, the presence of heavy metals (HMs) in the environment has become a critical issue, necessitating cost-effective and efficient techniques for their removal. The present study aimed to determine the optimal preparation conditions for synthesizing pectin (PC) as a polymer sorbent, combined with Magnesium (Mg) Aluminum (Al) layered double oxides (LDOs), using a fast and facile co-precipitation method. Both the response surface method (RSM) and the Taguchi method were employed to optimize the influence of key independent variables, including the molar ratio of cations Mg:Al, the ratio of pectin to LDO, and the temperature for removing multiple elements from wastewater. The results indicated that RSM is more accurate and examines more interactions, while Taguchi reduces the number of tests and is more economical than RSM. However, both statistical methods showed good potential for predicting the adsorption capacity (Qe) of HMs. The optimal preparation conditions were identified as a molar ratio of 3:1, a ratio of pectin to LDO of 7% w/w, and a temperature of approximately 600 °C. In conclusion, the application of RSM and Taguchi approaches was found to be feasible and effective in optimizing the preparation conditions of modified LDO, which can be utilized as a potential adsorbent for removing multiple elements from wastewater.

Pectin Hydrogels: Gel-Forming Behaviors, Mechanisms, and Food Applications

Pectin hydrogels have garnered significant attention in the food industry due to their remarkable versatility and promising properties. As a naturally occurring polysaccharide, pectin forms three-dimensional (3D) hydrophilic polymer networks, endowing these hydrogels with softness, flexibility, and biocompatibility. Their exceptional attributes surpass those of other biopolymer gels, exhibiting rapid gelation, higher melting points, and efficient carrier capabilities for flavoring and fat barriers. This review provides an overview of the current state of pectin gelling mechanisms and the classification of hydrogels, as well as their crosslinking types, as investigated through diverse research endeavors worldwide. The preparation of pectin hydrogels is categorized into specific gel types, including hydrogels, cryogels, aerogels, xerogels, and oleogels. Each preparation process is thoroughly discussed, shedding light on how it impacts the properties of pectin gels. Furthermore, the review delves into the various crosslinking methods used to form hydrogels, with a focus on physical, chemical, and interpenetrating polymer network (IPN) approaches. Understanding these crosslinking mechanisms is crucial to harnessing the full potential of pectin hydrogels for food-related applications. The review aims to provide valuable insights into the diverse applications of pectin hydrogels in the food industry, motivating further exploration to cater to consumer demands and advance food technology. By exploiting the unique properties of pectin hydrogels, food formulations can be enhanced with encapsulated bioactive substances, improved stability, and controlled release. Additionally, the exploration of different crosslinking methods expands the horizons of potential applications.

Microwave-assisted extraction of bioactive compounds from Sarawak Liberica sp. coffee pulp: Statistical optimization and comparison with conventional methods

Coffea liberica, commonly known as Liberica coffee, is a kind of coffee that originated in Liberia, a West African country. It is considered a less-known coffee bean variety, which accounts for less than 2% of commercially produced coffee worldwide. In this study, the influences of optimization of microwave-assisted extraction (MAE) on the total phenolic content (TPC), total flavonoid content (TFC), and total carbohydrate content (TCC) of bioactive compounds extracted from Sarawak Liberica sp. coffee pulp were studied. Response surface methodology was adopted with a face-centered central composite design to generate 34 responses by taking three microwave parameters into consideration, microwave power (watt), time of irradiation (second), and solvent-to-feed ratio as independent variables. As a result, the findings revealed that optimum extraction conditions were conducted as follows: microwave power of 700 W, time of irradiation of 180 s, and solvent-to-feed ratio of 86.644:1. While under optimal extraction conditions, MAE outperformed conventional maceration extraction in terms of extraction efficiency and had no significant difference (p < .05) with Soxhlet extraction on the extraction of TPC (12.94 ± 2.25 mg GAE/g), TFC (9.84 ± 0.38 mg QE/g), and TCC (876.50 ± 64.15 mg GE/g). Present work advances the usage of Sarawak Liberica sp. coffee for the development of functional products and aids in reducing environmental pollution by utilization of coffee pulp waste.

Effect of different extraction methods on antioxidant properties and encapsulation efficiency of anthocyanin of pomegranate peel

This study aimed to measure the efficiency, total anthocyanin content (TAC), and total phenol content (TPC) of pomegranate peel powder (PPP) extract from different extractions. Also, the characteristics of the nanoencapsulated extracts with maltodextrin (MD)/Lepidium perfoliatum (Qodume Shahri) seed gum were investigated. The highest and lowest extraction efficiency was related to solvent ethanol-water extraction (SEWE) (76.35%) and solvent ethanol extraction (SEE) (25.73%), respectively. Extracts obtained from microwave extraction (ME) and ultrasound extraction (UE) methods had the highest and lowest values of TAC (4.00-0.35) (mg C3G/g PPP) and TPC (702.13-232.58) (mg GAE/100 g sample), respectively. Peak 3213 in FT-IR indicates the O-H bond, which showed the highest content of phenolic compounds in the extract obtained from ME compared with SEE, SEWE, and UE. The nanoencapsulated extracts from SEE, SEE, and UE had the lowest particle size of peak 1, particle distribution in peak 1, and average particle size distribution compared with other extractions, respectively. The highest encapsulation efficiency of anthocyanin (EEA) and encapsulation efficiency of phenol (EEP) were related to UE (96.15%) and SEWE (86.57%), respectively. The EEP and EEA of SEE were not significantly different from ME and SEWE, respectively. On the other hand, the type and amount of extractive compounds in the extract have a great impact on the efficiency of nanoencapsulation and the average size distribution of nanoencapsulated particles. As a result, PPP extract is rich in antioxidant compounds, which can be determined by carefully examining the appropriate method of extraction and preservation of the extracted compounds.

Ultrasonic-assisted extraction for phenolic compounds and antioxidant activity of Moroccan Retama sphaerocarpa L. leaves: Simultaneous optimization by response surface methodology and characterization by HPLC/ESI-MS analysis

This study was designed to optimize the ultrasound-assisted extraction of phenolic compounds and the antioxidant activity of Moroccan Retama sphaerocarpa extracts using response surface methodology (RSM). A central composite design has been conducted to investigate the effects of three factors: extraction period (X₁), solvent concentration (X₂), and solvent-to-material ratio (X₃) on extraction yield, total phenolic content (TPC), flavonoids content (TFC), and antioxidant activity. The obtained results showed that the experimental values agreed with the predicted ones, confirming the capacity of the used model for optimizing the extraction conditions. The best extraction conditions for the simultaneous optimization were an extraction time of 38 min, a solvent concentration of 58%, and a solvent-to-material ratio of 30 mL/g. Under these conditions, the optimized values of yield, TPC, TFC, and DPPH-radical scavenging activity (DPPH_IC50) were 18.91%, 154.09 mg GAE/g, 23.76 mg QE/g, and 122.47 μg/mL, respectively. The further HPLC/ESI-MS analysis of the obtained optimized extract revealed the presence of 14 phenolic compounds with piscidic acid, vitexin, and quinic acid as major compounds. These research findings indicate promising applications for efficiently extracting polyphenolic antioxidants, especially in the food industry.

Orange Pomace and Peel Extraction Processes towards Sustainable Utilization: A Short Review

More than 58 million metric tonnes of oranges were produced in 2021, and the peels, which account for around one-fifth of the fruit weight, are often discarded as waste in the orange juice industry. Orange pomace and peels as wastes are used as a sustainable raw material to make valuable products for nutraceuticals. The orange peels and pomace contain pectin, phenolics, and limonene, which have been linked to various health benefits. Various green extraction methods, including supercritical carbon dioxide (ScCO₂) extraction, subcritical water extraction (SWE), ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE), are applied to valorize the orange peels and pomace. Therefore, this short review will give insight into the valorization of orange peels/pomace extraction using different extraction methods for health and wellness. This review extracts information from articles written in English and published from 2004 to 2022. The review also discusses orange production, bioactive compounds in orange peels/pomaces, green extractions, and potential uses in the food industry. Based on this review, the valorization of orange peels and pomaces can be carried out using green extraction methods with high quantities and qualities of extracts. Therefore, the extract can be used for health and wellness products.

Removal of methylene blue dye from aqueous solution using an efficient chitosan-pectin bio-adsorbent: kinetics and isotherm studies

Wastewater contains organic compounds, including dyes, which have potential risks to the environment. Hence, these compound needs to be eliminated from the aqueous solution. In the present study, chitosan-pectin composite (Cs-Pc) was used as an adsorbent to remove methylene blue dye (MB) from synthetic wastewater. To evaluate the parameters affecting adsorption, including the initial MB concentration, solution pH, contact time, and Cs-Pc dose, batch experiments were carried out. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR), and pH point of zero charges (pH pzc) were applied for characterizations of Cs-Pc. The optimum conditions were obtained with an initial MB concentration of 50 mg L^-1: solution pH ~ 11, Cs-Pc dose: 1.5 g L^-1 and 180 min contact time, which caused 97.77% of MB removal. In addition, the removal efficiency of MB was more influenced by pH than by sorbate dose. Also, Cs-Pc had a higher ability to remove MB than chitosan and pectin, probably due to its highly porous structure and rough surfaces that provides active sites and facilitate MB adsorption. The maximum removal efficiency and the adsorption capacity of MB onto Cs-Pc at 500 mg L^-1 concentration under optimum conditions were 98.67% and 328.02 mg g^-1, respectively. The adsorption kinetics and isotherms were best described by pseudo-second-order and Freundlich equation, respectively. After four times of recycling, the removal efficiency of MB was above 96%. Electrostatic and pi-pi interactions are the main mechanisms for the removal of MB onto the adsorbent. So the application of Cs-Pc is promising for MB removal from polluted solutions not only due to its strong adsorbing capability but also due to its excellent ability to reuse.

Sustainable approaches on industrial food wastes to value-added products - A review on extraction methods, characterizations, and its biomedical applications

The concept of zero waste discharge has been gaining importance in recent years towards attaining a sustainable environment. Fruit processing industries generate millions of tons of byproducts like fruit peels and seeds, and their disposal poses an environmental threat. The concept of extracting value-added bioactive compounds from bio-waste is an excellent opportunity to mitigate environmental issues. To date, significant research has been carried out on the extraction of essential biomolecules, particularly polysaccharides from waste generated by fruit processing industries. In this review article, we aim to summarize the different extraction methodologies, characterization methods, and biomedical applications of polysaccharides extracted from seeds and peels of different fruit sources. The review also focuses on the general scheme of extraction of polysaccharides from fruit waste with special emphasis on various methods used in extraction. Also, the various types of polysaccharides obtained from fruit processing industrial wastes are explained in consonance with the important techniques related to the structural elucidation of polysaccharides obtained from seed and peel waste. The use of seed polysaccharides as pharmaceutical excipients and the application of peel polysaccharides possessing biological activities are also elaborated.

Pectin Based Hydrogels for Drug Delivery Applications: A Mini Review

Over the past few decades, hydrogel systems using natural polymers have been expansively employed in drug delivery applications. Among the various reported biopolymer-based hydrogel drug delivery systems, pectin (Pec) is an exceptional natural polymer due to its unique functionalities and excellent properties such as biocompatibility, biodegradability, low-cost, and simple gelling capability, which has received considerable interest in the drug delivery fields. Since there is an increasing need for biomaterials with unique properties for drug delivery applications, in this review, hydrogels fabricated from natural pectin polymers were thoroughly investigated. Additionally, the present mini review aims to bring collectively more concise ways such as sources, extraction, properties, and various forms of Pec based hydrogel drug delivery systems and their toxicity concerns are summarized. Finally, the potential objectives and challenges based on pectin-based hydrogel drug delivery systems are also discussed.

Optimization of Extraction Parameters and Characterization of Tunisian Date Extract: A Scientific Approach Toward Their Utilization

The response surface methodology (RSM) was used in order to select the extraction conditions of extract from Kentichi date powder; a by-product of the date-processing process. Powder/solvent ratio, extraction temperature, and extraction time all had an impact on sugar yield, and these model factors have quadratic effects influencing sugar yield. Optimal extraction was obtained with 300 g/L powder/solvent ratio, 32.7 °C extraction temperature, and 2.1 h extraction time. Under these conditions, Kentichi date powder's (KDP) sugar yield was 77.1%, which was close to the predicted value of the model (80.50%). The results of Kentichi date powder extract (KDPE) showed that the total sugar content is 160.09 g/L. However, the protein content is 10.31 g/L with a majority of the essential amino acids (essentially glutamic acid (28.39 mg/L) and aspartic acid (9.65 mg/L)). The determination of antioxidant activity of KDPE showed a high activity (DPPH IC₅₀ = 4.8 mg/mL, ABTS IC₅₀ = 3 mg/mL, FRAP = 4.70 μmol AAE/mL and, TAA = 18.04 μmol Fe(II)/mL). The results show also that the freeze-drying technique has a lot of potential for producing powder from KDPE with many desirable properties. The findings indicate that KDPE with a high nutritional value could be used as a component for the formulation of functional foods.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12355-022-01223-2.

Evaluation of pectin extractions and their application in the alkaline Maillard reaction

A 2³ factorial design was used to evaluate the influence of temperature, catalyst and time and esterification degree (DE) of pectin obtained from mango, orange and tangerine peels as well as tamarind seeds by using the acid hydrolysis method. The study showed that a high temperature positively influenced the percentage of pectin yield for the four second generation biomasses. Nevertheless, the temperature showed a greater influence in the solubility and diffusion of the acid solvent in the tamarind seed matrix, resulting a pectin recovery 32.9%. Concerning the %DE, the most statistically significant value observed was dependent on the type of biomass studied. The %DE and the nature of the pectin are determining factors in the pectin's final use, in the present work the pectin extracted was used to produce furfural, a precursor of high value chemicals. The furfural production was achieved through alkaline hydrolysis and enhanced using the Maillard reaction, reaching a maximum concentration of 71.8 g/L which represents a 42.1% increase from the alkaline hydrolysis.

Study on anthocyanins from Lycium ruthenicum Murr via ultrasonic microwave synergistic extraction and its antioxidant properties

The objectives of this study are to optimize the ultrasonic microwave synergistic extraction (UMSE) of anthocyanins from Lycium ruthenicum Murr (ALRM) by response surface methodology and also to investigate its antioxidant activity in vitro. Based on the single-factor experiments, we optimized the ALRM extraction process by response surface methodology assuming anthocyanin extraction rate as the response point and microwave power, ultrasonic power, extraction time, and liquid-to-material ratio as the investigating parameters as well as performed correlation analysis between DPPH·, ·OH, ABTS·, O2-· radical scavenging potential, and ferric-reducing antioxidant power. The results showed that the influence on anthocyanin yield was in the order of liquid to material ratio &gt; microwave power &gt; ultrasonic power &gt; extraction time; the elicited extraction conditions were: ultrasonic power 216.253 W, microwave power 89.311 W, time 26.141 min, liquid to material ratio 17.294 mL/g, the forecast content was 10.157 mg/g, while the actual value was consistent with the preview value. Meanwhile, ALRM obtainable by UMSE was identified as yielding favorable antioxidant properties firstly, when the concentration of purified ALRM (ALRM-1) was increased, the antioxidant capacity was strengthened. Theoretically, we provide a basis for the extraction procedure of ALRM and its antioxidant activity, which serves as a promising antioxidant and free radical scavenger.

Utilisation of Pectins Extracted from Orange Peels by Non Conventional Methods in the Formation of Edible Films in the Presence of Herbal Infusions

Edible films of three high methoxy pectins (DE: 70–75%) in the presence of dittany and anise infusions were studied. Apart from a commercial one, two more pectins, selected by their yield and DE from preliminary experiments on pectin extraction from orange peels using ultrasound- and microwave-assisted extraction or a combination of both, were used. Extracted pectins were darker, less surface active and had lower [η] and absolute zeta values. All three pectin solutions were Newtonian. Furthermore, all films had statistically the same thickness (~40 μm) and moisture content (~25.2%). For the same herbal infusion, all pectins resulted in films with the same density (~1.01 and ~1.19 g/cm3 for dittany and anise films, respectively). Values of 2–4.65 N and 76.62–191.80 kPa, for maximum force and modulus, respectively, were reported. The commercial pectin film with anise was the stronger, whereas that with dittany, the stiffer. Total phenolics content (TPC) and antioxidant activity (SA) were also measured for films and film-forming solutions (FFS). TPC values ranged from 0.035 to 0.157 mg GAE/0.5 mL and SA from ~62 to 91%. Films had greater TPC but lower SA than their FFS. The presence of both pectin and herbal infusions were significant for our observations.

Microwave-assisted extraction of pectin from grape pomace

The utilization of microwave technique for the pectin extraction from grape pomace (Fetească Neagră and Rară Neagră), its influence on yield, galacturonic acid content, degree of esterification and molecular weight of pectin were analyzed. The optimal conditions of the extraction process were microwave power of 560 W, pH of 1.8 for 120 s. The pectin samples extracted by MAE in optimal conditions were analyzed by comparing with commercial apple and citrus pectin based on FT-IR analysis, thermal behavior, rheological characteristics and microstructure. The FT-IR analysis established the presence of different functional groups which are attributed to the finger print region of extracted pectin, while the rheological behavior presented a good viscoelasticity of pectin solutions. The obtained data assumes that grape pomace has a great potential to be a valuable source of pectin which can be extracted by simple and quick techniques, while maintaining analogous quality to conventional sources of pectin.

Ultrasound-Assisted Extraction of Anthocyanins from Malus ‘Royalty’ Fruits: Optimization, Separation, and Antitumor Activity

Red Malus ‘Royalty’ fruits are rich in anthocyanins. This study aimed to obtain the optimal parameters for the extraction and separation of anthocyanins from Malus ‘Royalty’ fruits and to evaluate the inhibitory effect of the enriched anthocyanin fraction on gastric cancer cells. Ultrasonic-assisted extraction was used for the extraction of the anthocyanins of Malus ‘Royalty’ fruit, and the extraction results showed that the optimum parameters were an extraction temperature of 20 °C, a solid–liquid ratio of 1:6 (g/mL), ethanol and formic acid contents of 70% and 0.4%, respectively, an extraction time of 40 min, and an ultrasonic power of 300 W. The optimum extraction parameters to achieve the highest anthocyanin yield by a single-factor experiment coupled with response surface methodology were identified. The separation results showed that the AB-8 macroporous resin was a better purifying material, with 60% ethanol as an adsorbent, and the adsorption–desorption equilibrium times were 6 h and 1 h, respectively. Cyanidin-3-galactoside was the main body composition separation of anthocyanins by a high-performance liquid chromatography-diode array detector. The antitumor activity results showed that the anthocyanins of Malus ‘Royalty’ fruits have a significant inhibitory effect on the gastric cancer cell line BGC-803. The in vitro cell viability test of CCK-8 showed that the inhibitory effect on tumor cells was more significant with the increased anthocyanin concentration, with a half maximal inhibitory concentration (IC₅₀) value of 105.5 μg/mL. The cell morphology was observed by an inverted microscope, and it was found that the backbone of BGC-803 treated with a high concentration of anthocyanins was disintegrated and the nucleoplasm was concentrated. The mechanism of apoptosis was analyzed by Western blotting, and the results showed that with increasing anthocyanin concentration in the medium, the expression levels of the proapoptotic proteins Bax and Bak increased, and the expression levels of the antiapoptotic proteins Bcl-2 and Bcl-xL decreased, which coordinated the regulation of cell apoptosis. This research suggests that the enriched anthocyanin fraction from Malus ‘Royalty’ fruits have potential antitumor and adjuvant therapeutic effects on gastric cancer.

Integrated emergent-floating planted reactor for textile effluent: Removal potential, optimization of operational conditions and potential forthcoming waste management strategy

Native emergent and floating plants; local reed grass (Phragmites karka) and water hyacinth (Eichhornia crassipes), respectively, were used to treat textile wastewater using an integrated emergent-floating planted reactor (IEFPR) system at hydraulic retention times (HRTs) of 8, 14, and 19 days. Real textile effluent having characteristics of 1686.3 ADMI for colour, 535 mg/L for total suspended solid (TSS), 647.7 mg/L for chemical oxygen demand (COD) and 124 mg/L for biochemical oxygen demand (BOD) was used throughout this study. The IEFPR system experienced maximum removal of colour (94.8%, HRT 14 days, day 3), TSS (92.7%, HRT 19 days, day 7), and COD (96.6%, HRT 8 days, day 5) at different HRT and exposure time. The process conditions (HRT and exposure time) were optimized for maximum colour, TSS and COD removal from textile effluent by employing response surface methodology (RSM). The optimization has resulted 100% removal of colour, 87% removal of TSS and 100% removal of COD at HRT of 8 days and exposure time of 5 days, with 0.984 desirability. The integrated plant-assisted treatment system showed reliable performance in treating textile wastewater at optimum operational conditions to improve effluent quality before disposal into water bodies or being recycled into the process. The potential of phytoremediator (produced plant biomass) to be utilized as resources for bioenergy or to be converted into value added products (adsorbent or biochar) provides an alternative to management strategy for better environmental sustainability.

Challenges and solutions of extracting value-added ingredients from fruit and vegetable by-products: a review

Every year, huge amounts of fruit and vegetable by-products in the food processing factories are produced. These by-products have great potential to be used for different targets especially the extraction of value-added ingredients. The target of this study is to review the challenges of extraction of value-added ingredients from fruit and vegetable by-products on the industrial scale and to describe current trends in solving these problems. In addition, some strategies such as multi-component extraction as well as application of fermentation before or after the extraction process, and production of biofuel, organic fertilizers, animal feeds, etc. on final residues after extraction of value-added ingredients are discussed in this review paper. In fact, simultaneous extraction of different value-added ingredients from fruit and vegetable by-products can increase the extraction efficiency and reduce the cost of value-added ingredients as well as the final volume of these by-products. After extraction of value-added ingredients, the residues can be used to produce biofuels, or they can be used to produce organic fertilizers, animal feeds, etc. Therefore, the application of several appropriate strategies to treat the fruit and vegetable by-products can increase their application, protect the environment, and improve the food economy.

Effect of different microwave power levels on inactivation of PPO and PME and also on quality changes of peach puree

The effect of microwave (MW) treatment with different power densities (4.4, 7.7, and 11.0 W/g) on polyphenol oxidase (PPO) and pectin methyl esterase (PME) inactivation in peach puree were studied, and the changes in color, rheological properties, total polyphenol and flavonoid and antioxidant capacity were evaluated. By using time/temperature data collected during MW heating, three cook values levels (0.36, 10, 24 min) for each power density were calculated. The PPO was significantly decreased from ca. 50% to ca. 5% when increasing the cook value level, regardless of power density applied. While PME significantly decreased from 40.6% to 10.2% when power density increased from 4.4 to 11.0 W/g at cook value 24 min. MW treatment did not alter the flow behaviour of peach puree. The apparent viscosity values of peach puree significantly increased after MW treatment with increasing cook value, regardless of power density applied. The L* values of peach puree significantly increased from 36.98 to 38.10 or more after MW treatment at cook value 10 min and 24 min. MW treatment could maintain the amount of total polyphenol, total flavonoid and antioxidant capacity, preserving the nutritional and functional values of the product.

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Same cook value of MW treatment resulted in similar inactivation level of PPO.

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PME significantly decreased when power density increased at cook value 3.

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PME was more resistant to MW treatment than PPO in peach puree.

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Higher cook value better preserved the antioxidants and antioxidant capacities.

Application of microwave and hydrothermal treatments for modification of cassava starch of Manipur region, India and development of cookies

The cassava (Manihot esculenta) root provides sustainable cheap source of starch that can be modified using microwave and hydrothermal treatments. The modified starch is of great demand in the market for its varied food applications. The microwave modified wet milling dry chips starch, microwave modified pulp starch (MD-PS), microwave modified dry chips starch were the microwave treated starch obtained from starches of pulp starch (PS), wet milling dry chips starch and dry milling dry chips starch, respectively. On the other hand, by using hydrothermal treatment followed by freeze-drying in PS gave autoclave freeze-dried 10% PS (AF-10PS), autoclave freeze-dried 20% PS (AF-20PS). The physicochemical and functional properties of the samples were investigated. The calorific value of modified starch was found to be 341-358 kcal/100 g. The microwave-modified starch lowered true densities as compared to hydrothermal treated starch. FT-IR spectra of microwave-modified starch confirmed six prominent peaks between 4500-500 cm^-1. Thermal treatment affected the digestibility and found lower digestion resistibility in modified starch compared to native starch. The structures of the starch granules were more enzymatically susceptible in hydrothermally modified starch. The microwave-modified starch resulted higher resistant starch as compared to hydrothermally modified starch. The cookies quality using MD-PS was checked by developing with 10-40% level of substitution of wheat flour. Overall cookies acceptability was found above sensory score 5. This study will help to provide functional ingredients that serve health benefit beyond nutrition.

Recent advances in valorization of citrus fruits processing waste: a way forward towards environmental sustainability

Citrus fruits are well known for their medicinal and therapeutic potential due to the presence of immense bioactive components. With the enormous consumption of citrus juice, citrus processing industries are focused on the production of juice but at the same time, a large amount of waste is produced mainly in the form of peel, seeds, pomace, and wastewater. This waste left after processing leads to environmental pollution and health-related hazards. However, it could be exploited for the recovery of essential oils, pectin, nutraceuticals, macro and micronutrients, ethanol, and biofuel generation. In view of the importance and health benefits of bioactive compounds found in citrus waste, the present review summarizes the recent work done on the citrus fruit waste valorization for recovery of value-added compounds leading to zero wastage. Therefore, instead of calling it waste, these could be a good resource of significant valuable components, in this way encouraging the zero-waste theory.

Advances in sustainable approaches utilizing orange peel waste to produce highly value-added bioproducts

Orange peel waste (OPW), a discarded part of orange fruit, is a rich source of essential constituents that can be transformed into highly value-added bioproducts. OPW is being generated in million tonnes globally and returns to the environment without complete benefit. Thus, a high volume of annually produced OPW in the industry requires effective valorization. In this regard, limited data is available that summarizes the broader spectrum for the sustainable fate of OPW to produce value-added bioproducts. The main objective of this treatise is to explore the sustainable production of bioproducts from OPW. Therefore, this review covers all the aspects of OPW, from its production to complete valorization. The review encompasses the extraction technologies employed for extracting different valuable bioactive compounds, such as: essential oil (EO), pectin, and carotenoids, from OPW. Furthermore, the suitability of bioconversion technologies (digestion/fermentation) in transforming OPW to other useful bioproducts, such as: biochemicals (lactic acid and succinic acid), biopolysaccharides (xanthan and curdlan gum), and bioenergy (biomethane and bioethanol) is discussed. Also, it includes the concept of OPW-based biorefineries and their development that shall play a definite role in future to cover demands for: food, chemicals, materials, fuels, power, and heat. Lastly, this review focuses on OPW-supplemented functional food products such as: beverages, yogurts, and extruded products. In conclusion, insights provided in this review maximize the potential of OPW for commercial purposes, leading to a safe, and waste-free environment.

Effects of isolation conditions on structural and functional properties of the seed gum from Chinese quince (Chaenomeles sinensis)

Chinese quince seed gum (CQSG) extracted under water-, alkali- and acid- conditions at 25, 50, and 80 °C, were evaluated in terms of yield, monosaccharide composition, molecular distribution, thermal gravimetry, emulsifying stability, rheological properties, and free radical scavenging ability. The results showed that the yield of CQSG increased to 3.9% after water extraction at 80 °C. Alkali and acid treatments promoted the conversion of neutral sugars to the uronic acid branch. Regardless of the extraction temperature, the xylose chain was the main component (35%-40%); however, a reduction was observed as the extraction temperature increased to 80 °C. All CQSG solutions extracted under these isolation conditions exhibited non-Newtonian rheological behavior. Compared to water-extracted samples, the alkali-extracted samples showed the worst thermal stability, while the acid-treated samples showed the worst emulsifying stability. This study provides theoretical support for the potential application of CQSG polysaccharides in the food and pharmaceutical industries.

Mango Peel Pectin: Recovery, Functionality and Sustainable Uses

Concerns regarding the overconsumption of natural resources has provoked the recovery of biopolymers from food processing biomass. Furthermore, the current market opportunity for pectin in other areas has increased, necessitating the search for alternative pectin resources. This is also a step towards the sustainable and circular green economy. Mango peel is the byproduct of agro-processing and has been used for high value-added components such as polysaccharide biopolymers. Pectin derived from the peel is yet to be exploited to its greatest extent, particularly in terms of its separation and physiochemical properties, which limit its applicability to dietary fiber in culinary applications. The functionality of the mango peel pectin (MPP) strongly depends on the molecular size and degree of esterification which highlight the importance of isolation and characterisation of pectin from this novel resource. This article therefore provides a useful overview of mango peel as a potential biomaterial for the recovery of MPP. Different extraction techniques and the integrated recovery were also discussed. The utilisation of MPP in different industrial schemes are also detailed out from different perspectives such as the pharmaceutical and biotechnology industries. This review convincingly expresses the significance of MPP, providing a sustainable opportunity for food and pharmaceutical development.

Strategies to improve the challenges of classic dispersive liquid-liquid microextraction for determination of the parabens in personal care products-One step closer to green analytical chemistry

Gas flow-assisted dispersive liquid-phase microextraction based on deep eutectic solvent was used to determine parabens in personal care products such as mouthwash, lidocaine gel, aloe vera gel, and skin tonic. A homemade extraction device was innovated, in which by passing the stream of gas bubbles through the deep eutectic solvent a thin layer of the extraction phase is coated on the surface of the bubbles. The extraction is finally achieved when the bubbles are going up through the sample. The single-factor experiments and response surface methodology were applied to optimize the independent variables. The linear range of the method was 0.5 to 1000 µg L^-1, the coefficient of determination for the goal analytes was higher than 0.9989, the instrumental limit of detections were in the range 0.2-0.3 μg L^-1, and the instrumental limit of quantifications were in the range 0.5-1.1 μg L^-1, the relative standard deviations were <5.2% for repeatability and <11.2% for intermediate precision, and the enrichment factors were 66 to 87 obtained under the optimized conditions. A spiking approach by means of standard material was used to estimate accuracy. The relative recoveries were in the range 95.8-105.2%. By using mentioned strategies, the organic waste and energy consumption reduced, toxic reagents replaced with safer ones, and operator safety enhanced. Accordingly, these benefits have been simultaneously attained and, the proposed method was one step closer to automation and sustainable analytical chemistry.

Functionality and Applicability of Starch-Based Films: An Eco-Friendly Approach

The accumulation of high amounts of petro-based plastics is a growing environmental devastation issue, leading to the urgent need to innovate eco-safe packaging materials at an equivalent cost to save the environment. Among different substitutes, starch-based types and their blends with biopolymers are considered an innovative and smart material alternative for petrol-based polymers because of their abundance, low cost, biodegradability, high biocompatibility, and better-quality film-forming and improved mechanical characteristics. Furthermore, starch is a valuable, sustainable food packaging material. The rising and growing importance of designing starch-based films from various sources for sustainable food packaging purposes is ongoing research. Research on "starch food packaging" is still at the beginning, based on the few studies published in the last decade in Web of Science. Additionally, the functionality of starch-based biodegradable substances is technically a challenge. It can be improved by starch modification, blending starch with other biopolymers or additives, and using novel preparation techniques. Starch-based films have been applied to packaging various foods, such as fruits and vegetables, bakery goods, and meat, indicating good prospects for commercial utilization. The current review will give a critical snapshot of starch-based films' properties and potential applicability in the sustainable smart (active and intelligent) new packaging concepts and discuss new challenges and opportunities for starch bio composites.

Citrus processing by-products: an overlooked repository of bioactive compounds

Citrus fruits contain plethora of bioactive compounds stored in edible as well as inedible part. Since, citrus fruits are processed mainly for juice, the residues are disposed in wastelands, hence, plenty of nutritional potential goes in vain. But if utilized wisely, the bioactive phytochemicals in citrus by-products have the ability to revolutionize the functional food industry. In the present review, the composition of citrus by-products in terms of bioactive components and their health benefits has been reviewed. Various extraction techniques used to extract these bioactives has been discussed and a brief overview of purification and utilization of the extracted compounds, in food and nutraceutical industry is also presented. Bioactives in citrus by-products are higher than the peeled fruit, which can be extracted, isolated and incorporated into food systems for development of health foods. From the studies reviewed, it was observed that research reported on utilization of citrus by-products is limited to mainly research labs; proper scale-up process and its adequate research commercialization is the need of hour to transform these bioactives into economical functional ingredients.

Microwave Assisted Extraction of Bioactive Carbohydrates from Different Morphological Parts of Alfalfa (Medicago sativa L.)

Despite the nutritional properties of alfalfa, its production is mainly for animal feed and it is undervalued as a food source. In this study, the valorization of alfalfa as a potential source of bioactive carbohydrates [inositols, α-galactooligosaccharides (α-GOS)] is presented. A Box–Behnken experimental design was used to optimize the extraction of these carbohydrates from leaves, stems, and seeds of alfalfa by solid–liquid extraction (SLE) and microwave-assisted extraction (MAE). Optimal extraction temperatures were similar for both treatments (40 °C leaves, 80 °C seeds); however, SLE required longer times (32.5 and 60 min vs. 5 min). In general, under similar extraction conditions, MAE provided higher yields of inositols (up to twice) and α-GOS (up to 7 times); hence, MAE was selected for their extraction from 13 alfalfa samples. Pinitol was the most abundant inositol of leaves and stems (24.2–31.0 mg·g⁻¹ and 15.5–22.5 mg·g⁻¹, respectively) while seed extracts were rich in α-GOS, mainly in stachyose (48.8–84.7 mg·g⁻¹). In addition, inositols and α-GOS concentrations of lyophilized MAE extracts were stable for up to 26 days at 50 °C. These findings demonstrate that alfalfa is a valuable source of bioactive carbohydrates and MAE a promising alternative technique to obtain functional extracts.

Sustainable electrode material for high-energy supercapacitor: biomass-derived graphene-like porous carbon with three-dimensional hierarchically ordered ion highways

Biomass-derived carbonaceous materials have been deemed to be one of the up-and-coming electrode materials for high-performance energy storage systems due to their cost-neutral abundant resources, sustainable nature, easy synthesis methods, and environmentally benign features. In this work, various graphene-like porous carbon networks (GPCs) with three-dimensional (3D) hierarchically ordered "ion highways" have been synthesized by the carbonization/activation of orange-peel wastes for use as an electrode material in high-energy supercapacitors. The porous structures and surface morphologies of the GPCs were rationally fine-tuned as a function of the activation agent ratio. The prepared GPCs offered superior specific surface area in addition to a 3D porous structure with a fine-tuned pore size distribution. The electrochemical behaviors of all the GPCs were evaluated in 6.0 M KOH aqueous electrolyte via a three-electrode electrochemical setup. Owing to their synergistic characteristics, including superior specific surface area (1150 m2 g-1), large pore volume, and fine-tuned 3D porous architecture, GPC-3.0 (synthesized with a KOH : GPC ratio of 3.0, by wt.) exhibited the best capacitive behavior amongst the studied GPCs. The 3D hierarchically ordered architecture acts like well-designed ion highways that boost electron transportation, thereby enhancing electrochemical energy storage. A coin-cell-type symmetrical supercapacitor based on GPC-3.0 was tested in both 1.0 M Na2SO4 (salt-in-water) and 12.0 m NaNO3 (water-in-salt) electrolytes. The supercapacitor cell based on the water-in-salt electrolyte offered a wide operating voltage of 2.3 V. The obtained energy density and power density values were comparable to those of commercial high-performance electrical double-layer capacitors. Such notable findings will shed light on next-generation high-rate electrochemical energy storage systems based on biomass-derived carbonaceous materials.

Recovery of anthocyanins from sour cherry (Prunus cerasus L.) peels via microwave assisted extraction: monitoring the storage stability

Utilization of economical and environmental methods as an alternative process to recover the industrial crops and food products into high-added value compounds is of great significant. In the current study, microwave assisted extraction (MAE) was optimized by response surface methodology (RSM) in order to evaluate the waste of sour cherry as a source of phenolic compounds rich in anthocyanins. The process parameters (microwave power, irradiation time and ethanol solvent concentration) of MAE method were optimized by face centered composite design of RSM. Responses such as total phenolic componds (TPC), total anthocyanin (TA) contents and antioxidant capacity (DPPH) of extracts were measured spectrophotometrically after extractions of samples. The optimized result of MAE was 500 W of microwave power, 90 s of irradation time and 80% ethanol solvent concentration. Antioxidant capacity was tested using by 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical. Chromatographic analysis (HPLC) was also used to measure the concentration of major anthocyanin (cyanidin-3-glucoside) of the samples. Maximum predicted TPC, TA and DPPH yields on optimized conditions were 44.15 mg-GAE/g-FM (mg- gallic acid equivalent per g- fresh matter), 12.47 mg-cyanidin-3-glucoside/g-FM and 69.90 (%, inhibition), respectively. A stability assay under different conditions (light, dark, ambient condition, refrigerator and deep freezer) has been also performed in order to display the stability of bioactivity profile. All of the process parameters were significant at the level of p < 0.0001.

Microstructure and physical properties of thermoplastic corn starch foams as influenced by polyvinyl alcohol and plasticizer contents

Thermoplastic starch (TPS) foams was prepared by melt extrusion process and the effects of polyvinyl alcohol (PVA) and glycerol/water plasticizer contents on the physical and cellular properties of these foams were investigated. All TPS/PVA blended foams showed more uniform cellular morphology, lower density and higher cell density than the TPS foam. The density of TPS foam decreased about 70%, and cell density increased up to 60-fold by adding 20% PVA. In addition to the positive effect of the PVA on improving processability and cellular uniformity, it also acted as a polymeric plasticizer and adding it allowed to decrease another low molecular weight plasticizer content in TPS/PVA blends. As a result by statistical analysis significant improvements in expansion ratio (256%), cell density (60 times), and lower moisture absorption (60%) were achieved.

Microwave-assisted extraction, characterization and immunomodulatory activity on RAW264.7 cells of polysaccharides from Trichosanthes kirilowii Maxim seeds

Microwave-assisted extraction of polysaccharides from Trichosanthes kirilowii Maxim seeds (TKMSP) was optimized using Response surface methodology (RSM) base on Central composite design (CCD). The optimum extraction conditions are detailed as follows: liquid-solid ratio 42 mL/g, extraction temperature 80 °C, microwave power 570 W, extraction time 26 min. Under this conditions, the mean value of TKMSP yield 2.43 ± 0.45% (n = 3), which was consistent closely with the predicted value (2.44%). The five polysaccharides (TKMSP-1, TKMSP-2, TKMSP-3, TKMSP-4 and TKMSP-5) were isolated from TKMSP by DEAE-52. TKMSP-1, TKMSP-2 and TKMSP-4 were common in containing Man, Rib, Rha, GluA, GalA, Glu, Gal, Xyl, Arab and Fuc. However, there was no Fuc in TKMSP-3, while TKMSP-5 lacked GluA, GalA and Fuc. UV–vis and FT-IR analysis combined with molecular weight determination further indicated that the five fractions were polydisperse polysaccharides. A significant difference was achieved in the structural characterization of these five fractions. TKMSP exhibited immunosuppressive activity on RAW264.7 cells. It can be applied as a potential immunosuppressant agent in medicine.

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Microwave-assisted extraction of TKMSP optimized by RSM base on CCD.

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The five polydisperse polysaccharides were isolated from TKMSP.

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The structure characterizations of the five polysaccharides were analyzed.

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TKMSP-3 exhibited significant inhibition of RAW264.7 proliferation.