Antioxidant and antimicrobial activity of pomegranate peel extract improves the shelf life of chicken products

Exploring the potential of Mon-Pu (Glochidion wallichianum) leaf extract as a natural antioxidant for Ligor chicken meat gel: Impact on gelation functionality and oxidative stability

This study evaluated the antioxidant potential of Mon-Pu (Glochidion wallichianum Mull. Arg.) leaf extract (MPLE) as a natural antioxidant in Ligor chicken meat gels. The investigation focused on the impacts on gelation functionality and oxidative stability during refrigerated storage. MPLE with 21.16 mg/100 g of extractable phenolic compounds and antioxidant potency (DPPH• scavenging activity, ABTS•+scavenging activity, and ferric reducing antioxidant power (FRAP) at 2.79, 21.13, and 3.20 mmole TE/g, respectively) was applied during thermal-induced gel preparation at different concentrations (0 %, 0.01 %, 0.1 %, and 1 %) in comparison with 1 % gallic acid, a reported key phenolic compound in MPLE, based on the total weight of the meat sample. MPLE at concentrations of 0.1-1 % effectively reduced lipid oxidation in Ligor meat gel during storage. Additionally, MPLE at 0.1 % inhibited protein oxidation, preserving the physical and textural qualities of meat gels during processing and refrigerated storage. Notably, MPLE at 0.1 % proved to be the most beneficial, retaining gel properties, enhancing water-holding capacity, stabilizing color, and reducing oxidative degradation. These findings indicate that MPLE, at an optimal concentration of 0.1 %, has significant potential as a natural preservative, providing a safer and more effective alternative to synthetic additives for maintaining gel properties and preserving oxidative stability of chicken meat products, particularly Ligor chicken meat gel.

Promoting the Emerging Role of Pulse By-Products as Valuable Sources of Functional Compounds and Novel Food Ingredients

The growth of the human population worldwide has increased food demand, generating the massive production of foods and consequently causing enormous production of waste every year. The indiscriminate exploitation of the already limited natural resources has also generated serious environmental and economic crises. The use, or reuse, of waste or by-products represents a viable solution to constrain the problem by promoting alternative routes of exploitation with multiple food and biotechnological applications. This review focuses on the most recent advances in the valorization of food by-products, with specific reference to legume-derived by-products. The main technological solutions for reintroducing and/or valorizing food waste are reported together with a critical discussion of the main pros and cons of each alternative, supported by practical case studies whenever available. First, the possibility to exploit the by-products as valuable sources of functional compounds is presented by reviewing both conventional and innovative extraction techniques tailored to provide functional extracts with multiple food, pharmaceutical, and biotechnological applications. Second, the possibility to valorize the by-products as novel food ingredients by inclusion in different formulations, either as a whole or as hydrolyzed/fermented derivatives, is also presented and discussed. To the best of our knowledge, several of the technological solutions discussed have found only limited applications for waste or by-products derived from the legume production chain; therefore, great efforts are still required to gain the full advantages of the intrinsic potential of pulse by-products.

Comparative phytochemical and biological assessment of Punica granatum (pomegranate) peel extracts at different growth stages in the Taif region, Saudi Arabia

The medicinal and commercial value of pomegranate peel is attributed to its rich content of phenolic compounds, yet little is known about their concentrations and biological activity across different ripening stages. Pomegranate peels at different growth stages 1-3 (40, 80, and 120 days after fruit appearance respectively) were collected, dried, and macerated with 90% methanol. Stage 2 and stage 3 extract showed significant antimicrobial activity against S. aureus, and L. monocytogenes. Further, stage 2 extract showed highest efficacy against lung, breast, and liver cancer cells with IC50 values of 19.76 ± 1.3, 24.28 ± 6.99, and 16.04 ± 2.78 µg/mL, respectively. Molecular docking, and simulation further confirmed the antimicrobial and cytotoxic activity of the most prominent stage 2 phytoconstituent (γ-Sitosterol). The study indicates that stage 2 pomegranate peel extract has potential as a safe and natural antimicrobial and cytotoxic agent. However, additional in vitro and in vivo testing is needed to validate these results.

Combining the Powerful Antioxidant and Antimicrobial Activities of Pomegranate Waste Extracts with Whey Protein Coating-Forming Ability for Food Preservation Strategies

Different solvents water, ethanol and ethanol/water (6:4 v/v), were compared in the extraction of pomegranate peels and seeds (PPS) in terms of recovery yields, antioxidant properties, and antimicrobial action against typical spoilage bacterial and fungal species. The best performing extract (ethanol/water (6:4 v/v) was shown to contain mostly ellagic acid and punicalagin as phenolic compounds (5% overall) and hydrolysable tannins (16% as ellagic acid equivalents) and was able to inhibit the growth of the acidophilic Alicyclobacillus acidoterrestris at a concentration as low as 1%. The preservation of the organoleptic profile of A. acidoterrestris-inoculated apple juice with extract at 1% over 20 days was also observed thanks to the complete inhibition of bacterial growth, while the extract at 0.1% warranted a significant (40%) inhibition of the enzymatic browning of apple smoothies over the first 30 min. When incorporated in whey proteins' isolate (WPI) at 5% w/w, the hydroalcoholic extract conferred well appreciable antioxidant properties to the resulting coating-forming hydrogel, comparable to those expected for the pure extract considering the amount present. The WPI coatings loaded with the hydroalcoholic extract at 5% were able to delay the browning of cut fruit by ca. 33% against a 22% inhibition observed with the sole WPI. In addition, the functionalized coating showed an inhibition of lipid peroxidation of Gouda cheese 2-fold higher with respect to that observed with WPI alone. These results open good perspectives toward sustainable food preservation strategies, highlighting the potential of PPS extract for the implementation of WPI-based active packaging.

Pomegranate Peel and Olive Leaf Extracts to Optimize the Preservation of Fresh Meat: Natural Food Additives to Extend Shelf-Life

Quality and safety are one of the main concerns of the European Union in food preservation. Using chemical additives extends the shelf-life of fresh foods but raises consumer's concerns about the potential long-term carcinogenic effects. Using natural substances derived from agro-industrial by-products, which have significant antimicrobial and antioxidant activities, could extend the shelf-life of fresh foods such as meat. Furthermore, they can provide nutritional improvements without modifying organoleptic properties. This study analyzes the antimicrobial activity of pomegranate peel extract (PPE) and the antioxidant activity of olive leaf extract (OLE), added at concentrations of 10 mg g-1 and 0.25 mg g-1, respectively, to minced poultry and rabbit meat. PPE exhibited in vitro antimicrobial activity against foodborne pathogens starting at 10 mg/well. PPE and OLE determined a reduction in colony count over a storage period of 6 days at 4 °C. Additionally, the combination of PPE and OLE showed antioxidant effects, preserving lipid oxidation and maintaining pH levels. The obtained results demonstrate that PPE and OLE can be recommended as food additives to preserve the quality and extend the shelf-life of meat products.

Potential applications of Rhodomyrtus tomentosa leaf extract as natural anti-staphylococcal additive in food systems: Efficacy and in vivo safety evaluation

This work aimed to explore the potential use of Rhodomyrtus tomentosa ethanol leaf extract (RTEL) as an alternative food preservative agent for controlling the growth of Staphylococcus aureus. Antibacterial activities against food-isolated S. aureus were performed using disc diffusion and broth microdilution assays, followed by evaluating in vivo subacute oral toxicity of the extract. Salad dressing was used as a food model to study bactericidal properties and consumer acceptability. RTEL remarkably inhibited S. aureus with minimum inhibitory concentrations (MICs) ranging from 7.81-62.5 µg/mL. Repeated oral doses (5, 50, and 300 mg/kg RTEL) for 28 days did not affect any of the measured toxicity parameters. The no-observed-adverse-effect-level (NOAEL) of RTEL was noted as more than 300 mg/kg body weight/day. The utilization of RTEL (12.5 mg/mL) in the vinaigrette salad dressing did not affect the consumer acceptability of the product, remarkably killed the pathogen within 3-9 h of exposure. The results indicated that RTEL is safe and effective as a natural anti-staphylococcal controlling agent that could be utilized in food systems. Further work is required on the effects of enterotoxin production, an important virulence factor of S. aureus responsible for food-borne disease.

Free-standing carboxymethyl cellulose film incorporating nanoformulated pomegranate extract for meat packaging

This study aimed to explore an innovative approach to enhancing the shelf-life and quality of meat products through the application of an active packaging system. The study involved the development of new free-standing carboxymethyl cellulose (CMC) nanocomposite films incorporated with nanoencapsulated flavonoids derived from pomegranate extract. The loaded flavonoids, known for their antioxidant and antimicrobial properties, were nanoencapsulated via a self-assembly approach in a mixture of chitosan and sodium alginate to improve their stability, solubility, and controlled release characteristics. Chemical structure, size, and morphology of the obtained nanoparticles (Pg-NPs) were studied with FTIR, zeta-sizer, and TEM. The Pg-NPs showed particle size of 232 nm, and zeta-potential of -20.7 mV. Various free-standing nanocomposite films were then developed via incorporation of Pg-NPs into CMC-casted films. FTIR, SEM, thermal and mechanical properties, and surface wettability were intensively studied for the nanocomposite films. Barrier properties against water vapor were investigated at 2022 g·m-2d-1. The nanocomposite films possessed superior properties for inhibiting bacterial growth and extending the shelf-life of beef and poultry meat for 12 days compared with the Pg-NPs-free CMC films. This study presented a promising approach for development of active packaging systems with improved antimicrobial and antioxidant properties, and economic and environmental impacts.

An in vivo appraisal of Punica granatum peel extract's ultrastructural effect on cystic echinococcosis in mice

In the past decade, interest has significantly increased regarding the medicinal and nutritional benefits of pomegranate (Punica granatum) peel. This study examined the effects of using pomegranate peel extract (PGE) alone and in combination with albendazole (ABZ) on ultrastructural and immunological changes in cystic echinococcosis in laboratory-infected mice. Results revealed that the smallest hydatid cyst size and weight (0.48 ± 0.47mm, 0.17 ± 0.18 gm) with the highest drug efficacy (56.2%) was detected in the PGE + ABZ group, which also exhibited marked histopathological improvement. Ultrastructural changes recorded by transmission electron microscopy including fragmentation of the nucleus, glycogen depletion, and multiple lysosomes in vacuolated cytoplasm were more often observed in PGE + ABZ group. IFN-γ levels were significantly increased in the group treated with ABZ, with a notable reduction following PGE treatment, whether administered alone or in combination with ABZ. Thus, PGE enhanced the therapeutic efficiency of ABZ, with improvement in histopathological and ultrastructural changes.

Antimicrobial efficacy of Punica granatum Lythraceae peel extract against pathogens belonging to the ESKAPE group

The improper use and abuse of antibiotics have led to an increase in multidrug-resistant (MDR) bacteria resulting in a failure of standard antibiotic therapies. To date, this phenomenon represents a leading public health threat of the 21st century which requires alternative strategies to fight infections such as the identification of new molecules active against MDR strains. In the last 20 years, natural extracts with biological activities attracted scientific interest. Following the One Health Approach, natural by-products represent a sustainable and promising alternative solution. Consistently, the aim of the present study was to evaluate the antimicrobial activity of hydro-alcoholic pomegranate peel extract (PPE) against MDR microorganisms belonging to Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. "ESKAPE" group pathogens. Through semiquantitative and quantitative methods, the PPE showed effective antimicrobial activity against Gram-positive and Gram-negative MDR bacteria. The kinetics of bactericidal action of PPE highlighted that microbial death was achieved in a time- and dose-dependent manner. High concentrations of PPE exhibited antioxidant activity, providing a protective effect on cellular systems and red blood cell membranes. Finally, we report, for the first time, a significant intracellular antibacterial property of PPE as highlighted by its bactericidal action against the staphylococcal reference strain and its bacteriostatic effect against clinical resistant strain in the HeLa cell line. In conclusion, due to its characterized content of polyphenolic compounds and antioxidant activity strength, the PPE could be considered as a therapeutic agent alone or in conjunction with standard antibiotics against challenging infections caused by ESKAPE pathogens.

Improved Cardiovascular Effects of a Novel Pomegranate Byproduct Extract Obtained through Hydrodynamic Cavitation

The healthy properties of pomegranate fruit, a highly consumed food, have been known for a long time. However, the pomegranate supply chain is still rather inefficient, with the non-edible fraction, whose weight is roughly half the total and is endowed with plenty of valuable bioactive compounds, either disposed of or underutilized. A novel extract obtained from non-edible byproducts (called PPE), using hydrodynamic cavitation, a green, efficient, and scalable technique, was investigated for its cardiovascular effects in vivo. PPE showed efficacy in an acute phenylephrine (PE)-induced hypertensive rat model, similar to the extract of whole fruit (PFE) obtained using the same extractive technique, along with good intestinal bioaccessibility after oral administration. Finally, when chronically administered for 6 weeks to spontaneously hypertensive rats, PPE was shown to significantly contain the increase in systolic blood pressure, comparable to the reference drug Captopril, and at a dose remarkably lower than the reported effective dose of ellagic acid. The extract from the non-edible fraction of the pomegranate fruit also showed good anti-inflammation and anti-fibrotic effects. The findings of this study, along with the extraction technique, could contribute to enhancing the value of the pomegranate supply chain, relieve the related environmental burden, and potentially improve public health.

Punica granatum peel extract modulates levofloxacin-induced oxidative stress and testicular damage in rats

Levofloxacin (LEV) is one of the Fluoroquinolones antibiotic groups, which are utilized in the therapy of numerous diseases, particularly in reproductive organs. Punica granatum peel is a waste byproduct rich in phytochemicals that are known for their different biological activities. The current research was designed to assess the capability of pomegranate peel extract (PGPE) in counteracting LEV-induced oxidative stress and testicular injury in rats. Rats groups were divided as follows: control, PGPE (500 mg/kg BW), LEV (300 mg/kg BW), and PGPE plus LEV. Rats were treated orally for two weeks daily. The chemical and nutritional content of Punica granatum peel (PGP) were investigated. GC/MS analysis showed the major phytochemical constituents in PGPE as gallic acid, ellagic acid, 4H-Pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl, and caffeic acid with DPPH, ABTS, and NO radical scavenging activity, as well as Fe3+- reducing antioxidant activity. Results revealed that LEV increased TBARS and H2O2 concentrations and LDH activity in rat testes significantly. While the activities of antioxidant enzymes, phosphatases, aminotransferases, and reduced glutathione content as well as protein levels, were significantly reduced. Worthy changes in testosterone, luteinizing, and follicle-stimulating hormone levels, as well as sperm characteristics, were also discovered. LEV was also found to trigger apoptosis, as evidenced by elevated p53 and caspase-3 levels and decreased Bcl2 levels. Furthermore, alterations in histological and immunohistochemical PCNA expression were observed in rat testes, confirming the biochemical findings. Furthermore, PGPE pretreatment of LEV-treated rats restored the majority of the tested parameters when compared to the LEV-treated group. In conclusion, pomegranate peel extract had a powerful modulating role against the adverse effects of levofloxacin in rat testes and represents a perspective of the utilization of food waste by-products.

Effects of Thyme Essential Oil Microcapsules on the Antioxidant and Quality Characteristics of Mutton Patties

This study aimed to assess the stability of thyme essential oil microcapsules (TEOMs) and their impacts on the antioxidant properties and quality of lamb patties. The results demonstrated that gum Arabic effectively enhanced the stability of phenols within the thyme essential oil (TEO), with an optimal core/wall ratio of 1:8. Substituting TEO with TEOMs in lamb patties led to reductions in the thiobarbituric acid content, carbonyl content, sulfhydryl loss, and protein cross-linking. Additionally, the TEOMs positively influenced the mutton patties' color, texture, microbiological stability, and sensory attributes. These findings substantiate the idea that TEOMs exhibit significant potential as a natural preservative to enhance the quality of mutton patties.

Development of chicken tender pops by utilizing pomegranate peel powder

Pomegranate peel powder (PPP) is a rich source of many bioactive components particularly polyphenols that are interlinked to various technological and functional properties. In the present study, chicken tender pops were developed with incorporation of PPP, and its effect on quality attributes and storage stability of the product were evaluated. The treatments were formulated using 0%, 3%, 6%, and 9% PPP in replacement of chicken. The physicochemical properties, texture profile, instrumental color, sensory attributes, and storage stability were assessed for 21 days at refrigeration temperature, at a regular interval of 7 days. The results indicated that the inclusion of PPP significantly (p < .05) increased the dietary fiber from 0.25% in T0 to 1.45% in T3 at Day 0 and WHC 43.60% ± 0.02 in T0 to 49.36% ± 0.02 in T3 at Day 0, whereas the moisture content significantly reduced from 60.05% ± 0.03 in T0 to 55.08% ± 0.01 in T3 at the start of the study. In addition, the values of TBARS were significantly (p < .05) reduced for treated samples 0.72 mg MDA/Kg in T3 as compared to control 1.17 mg MDA/Kg on the 21st day of storage, whereas a significant increase (p < .05) in TPC from 0.90 mg GAE/g to 3.87 mg GAE/g in T0 to T3 was observed at the start of the study. For TPA, a significant (p < .05) increase was noticed in hardness, chewiness, and gumminess, whereas cohesiveness and springiness showed a non-significant (p > .05) change in treated samples in relation to control, and the instrumental color (L* and a*) decreased significantly. However, pH, crude fiber, fat, ash, and protein content showed non-significant (p > .05) variations over time. The sensory evaluation suggested that chicken tender pops supplemented with 6% PPP (T2) presented high overall acceptability and balanced organoleptic properties. Hence, it can be concluded that PPP can be effectively utilized as a natural fiber source, antioxidant, and antimicrobial agent in novel functional foods.

The effects of pomegranate peel added bread on anthropometric measurements, metabolic and oxidative parameters in individuals with type 2 diabetes: a double-blind, randomized, placebo-controlled study

BACKGROUND/OBJECTIVES

The aim of this study was to evaluate the sensory properties of antioxidant-rich bread made by adding pomegranate peels and their effects on anthropometric measurements and metabolic and oxidative parameters of individuals with type 2 diabetes after consumption.

SUBJECTS/METHODS

This randomized, double-blind, placebo-controlled study was conducted with 22 individuals aged between 19 and 64 years who had been diagnosed with type 2 diabetes for at least 5 years, used only metformin, did not lose more than 10% of their body weight in the last 6 months, and had a body mass index of ≥ 25.0 kg/m². While the study group (n = 11) consumed bread containing 500 mg pomegranate peel daily for 8 wk, the control group (n = 11) consumed standard bread. Anthropometric measurements and metabolic and oxidative parameters of individuals were evaluated at the beginning and end of the study.

RESULTS

Decreases were detected in the waist circumference, waist/hip and waist/height ratios, body fat percentages, blood pressure, and serum insulin, triglyceride, and total cholesterol levels in the individuals in the treatment group, compared with those in the control group (P < 0.05).

CONCLUSIONS

Pomegranate peel consumption by individuals with type 2 diabetes may have positive effects on anthropometric measurements and glycemic and lipid parameters.

A Natural Feed Additive Phytobiotic, Pomegranate (Punica granatum L.), and the Health Status of Poultry

The addition of antibiotic growth promotors in poultry diets results in a development of resistant bacterial strains and accumulation of drug residues in the meat and eggs. The new trend in poultry industry is the dietary addition of natural feed additives including phytobiotics. Pomegranate (Punica granatum L.) is a natural cheap feed source that has been extensively used in the livestock production. In poultry production system, pomegranate by-products such as peel powder or extract, seed oil, or juice showed high nutritional values, several health benefits, and good economic profits. Pomegranate displays a growth promoting effect and an enhancement of carcass traits of broilers, along with an improvement of the egg production traits parameters. Moreover, dietary pomegranate by-products showed a potential antioxidant and antimicrobial effects on the treated birds. Modulation of both humeral and cell mediated immune response, hypo-lipidemia, as well as enhancement of liver functions have been proved following dietary treatment with different pomegranate by-products. Therefore, this review article was designed to present the different effects of dietary pomegranate by-products on the production indices of broilers and layers, the antioxidant, antimicrobial, and immune status, as well as the blood parameters.

An Overview of the Health Benefits, Extraction Methods and Improving the Properties of Pomegranate

Pomegranate (Punica granatum L.) is a polyphenol-rich edible food and medicinal plant of ancient origin, containing flavonols, anthocyanins, and tannins, with ellagitannins as the most abundant polyphenols. In the last decades, its consumption and scientific interest increased, due to its multiple beneficial effects. Pomegranate is a balausta fruit, a large berry surrounded by a thick colored peel composed of exocarp and mesocarp with edible arils inside, from which the pomegranate juice can be produced by pressing. Seeds are used to obtain the seed oil, rich in fatty acids. The non-edible part of the fruit, the peel, although generally disposed as a waste or transformed into compost or biogas, is also used to extract bioactive products. This review summarizes some recent preclinical and clinical studies on pomegranate, which highlight promising beneficial effects in several fields. Although further insight is needed on key aspects, including the limited oral bioavailability and the role of possible active metabolites, the ongoing development of suitable encapsulation and green extraction techniques enabling the valorization of waste pomegranate products point to the great potential of pomegranate and its bioactive constituents as dietary supplements or adjuvants in therapies of cardiovascular and non-cardiovascular diseases.

Oxidative Stability of Avocado Snacks Formulated with Olive Extract as an Active Ingredient for Novel Food Production

Analysis of the oxidative stability of novel avocado chips with added natural extracts was carried out with the aim of reducing the chemical additive content in their formulation. Two different natural extracts were initially evaluated and characterized: one obtained from olive pomace (OE) and other from pomegranate seed waste. OE was selected due to its better antioxidant potential according to FRAP, ABTS, and DPPH assays as well as its higher total phenolic content. The formulations used were 0, 1.5 wt.%, and 3 wt.% of OE. A gradual disappearance of the band found around 3009 cm^-1 and related to unsaturated fatty acids was observed in the control sample in contrast to formulations with added OE. The band observed near 3299 cm^-1 widened and intensified with time due to the oxidation degree of samples, with this effect being higher in the control chips. The observed changes in fatty acid and hexanal content with storage time underlined the higher extent of oxidation in the control samples. This fact could suggest an antioxidant protectant action of OE in avocado chips during thermal treatment, which was attributed to the presence of phenolic compounds. The obtained chips incorporating OE represent a viable option for the development of a natural, healthy, and clean-label avocado snack at competitive cost and with low environmental impacts.

Synthetic and natural antimicrobials as a control against food borne pathogens: A review

Food borne pathogens are one of the most common yet concerning cause of illnesses around the globe. These microbes invade the body via food items, through numerous mediums of contamination and it is impossible to completely eradicate these organisms from food. Extensive research has been made regarding their treatment. Unfortunately, the only available treatment currently is by antibiotics. Recent exponential increase in antibiotic resistance and the side effect of synthetic compounds have established a need for alternate therapies that could be utilized either on their own or along with antibiotics to provide protection against food-borne diseases. The aim of this review is to provide information regarding some common food borne diseases, their current and possible natural treatment. It will include details regarding some common foodborne pathogens, the disease they cause, prevalence, manifestations and treatment of the respective disease. Some natural modes of potential treatment will be summarized, which including phytochemicals, derived from plants either as crude extracts or as purified form and Bacteriocins as microbial based treatment, obtained from various types of bacteria. The paper will describe their mechanism of action, classification, susceptible organisms, some antimicrobial compounds and producing organisms, application in food systems and as potential treatment. Along with that, synthetic treatment i.e., antibiotics will be discussed including the first-line treatment of some common food borne infections, prevalence and mechanism of resistance against antibiotics in the pathogens.

Exploring the Potential of Pomegranate Peel Extract as a Natural Food Additive: A Review

PURPOSE OF THE REVIEW

Pomegranate is one of the super fruit and a storehouse of several antioxidants and health-promoting compounds which can act as a natural food additive. The pomegranate processing industry generates huge quantities of by-products, particularly peels (50% of fresh fruit weight), that cause environmental pollution due to improper disposal. In this perspective, the present review article focuses on the chemical composition of pomegranate peel and its application as a natural food additive in different food products such as bakery, dairy, meat/meat products, fish/fish products, edible oils, and packaging materials.

RECENT FINDINGS

There is a continuous demand for processed foods exhibiting natural food additives over foods containing synthetic additives/colorants, which can cause serious health implications such as cancer with regular consumption. The food industry is looking for an alternative to synthetic/artificial food additives. To overcome these problems, pomegranate peel or its extract can be used as a natural biopreservative in food products that are prone to fat oxidation and microbial growth. Pomegranate peel contains bioactive compounds, especially tannins, phenolic acids, and flavonoids, which have nutraceutical value and possess higher antioxidant activity and antimicrobial properties. Due to these properties, pomegranate peel prevents lipid oxidation in fatty foods and can also retard the microbial growth.

Valorization of Food Waste to Produce Value-Added Products Based on Its Bioactive Compounds

The rapid growth of the global population and changes in lifestyle have led to a significant increase in food waste from various industrial, agricultural, and household sources. Nearly one-third of the food produced annually is wasted, resulting in severe resource depletion. Food waste contains rich organic matter, which, if not managed properly, can pose a serious threat to the environment and human health, making the proper disposal of food waste an urgent global issue. However, various types of food waste, such as waste from fruit, vegetables, grains, and other food production and processing, contain important bioactive compounds, such as polyphenols, dietary fiber, proteins, lipids, vitamins, organic acids, and minerals, some of which are found in greater quantities in the discarded parts than in the parts accepted by the market. These bioactive compounds offer the potential to convert food waste into value-added products, and fields including nutritional foods, bioplastics, bioenergy, biosurfactants, biofertilizers, and single cell proteins have welcomed food waste as a novel source. This review reveals the latest insights into the various sources of food waste and the potential of utilizing bioactive compounds to convert it into value-added products, thus enhancing people’s confidence in better utilizing and managing food waste.

Pomegranate (Punica granatum) peel alleviates lithium-induced alterations in the thyroid gland of rats by modulating apoptosis and oxidative stress

Lithium carbonate (LC) is known to alter thyroid gland function. Pomegranate (PG) is a fruit with multiple antioxidant and antiapoptotic properties. Here, we studied the effect of PG on LC-induced morphological and functional alterations in the thyroid glands of rats. Rats were divided into four groups: control, lithium, lithium-PG, and PG. After 8 weeks, the rats were sacrificed, the levels of thyroid hormones and oxidative stress markers were estimated, and thyroid tissues were subjected to histological, immunohistochemical, and ultrastructural evaluations. Compared to the control group, the lithium group showed significant changes in thyroid hormone levels, greater expression of the oxidant marker malondialdehyde, and lower expression of the antioxidant marker superoxide dismutase (SOD). Most of these changes improved upon PG treatment. Histological evaluation of the thyroid in the lithium group showed disorganization and follicle involution. Additionally, the periodic acid Schiff staining intensity and SOD immunoreactivity declined significantly, whereas the collagen fiber content and Bax immunoreactivity increased. The follicular ultrastructure showed marked distortion. These changes were mitigated upon PG treatment. In conclusion, PG alleviated the morphological and functional changes in the thyroid glands induced by LC by modulating apoptosis and oxidative stress.

Valorization of Fruit Waste for Bioactive Compounds and Their Applications in the Food Industry

The fruit production and processing sectors produce tremendous amounts of by-products and waste that cause significant economic losses and an undesirable impact on the environment. The effective utilization of these fruit wastes can help to reduce the carbon footprint and greenhouse gas emissions, thereby achieving sustainable development goals. These by-products contain a variety of bioactive compounds, such as dietary fiber, flavonoids, phenolic compounds, antioxidants, polysaccharides, and several other health-promoting nutrients and phytochemicals. These bioactive compounds can be extracted and used as value-added products in different industrial applications. The bioactive components extracted can be used in developing nutraceutical products, functional foods, or food additives. This review provides a comprehensive review of the recent developments in fruit waste valorization techniques and their application in food industries. The various extraction techniques, including conventional and emerging methods, have been discussed. The antioxidant and antimicrobial activities of the active compounds extracted and isolated from fruit waste have been described. The most important food industrial application of bioactive compounds extracted from fruit waste (FW) has been provided. Finally, challenges, future direction, and concluding remarks on the topic are summarized.

Development of fermented sea buckthorn (Hippophae rhamnoides L.) juice and investigation of its antioxidant and antimicrobial activity

Sea buckthorn (Hippophae rhamnoides L.) is an edible and medicinal plant species. However, due to its sour taste, it is not readily accepted by consumers. To overcome this, fermentation can be used to change its flavor profile. In this study, we used response surface methodology (RSM) to determine the best process for producing fermented sea buckthorn juice (FSBJ) using probiotics. The biological enzyme activity and total flavonoid content (TFC) of sea buckthorn juice (SBJ) increased after fermentation. When the number of bacteria inoculated was 4.08 × 10⁶ CFU/mL and the inoculation ratio was 30% Z. mobilis, 5% L. casei, 13.75% L. plantarum, 31.25% P. acidilactici, 12.5% L. animalis, and 7.5% P. pentosaceus, the amount of sugar was 2.98% (w/v) after 20 h of fermentation at 37°C, and the superoxide dismutase (SOD) activity reached 725.44 U/mL, and the TFC reached 2.38 mg/mL. FSBJ demonstrated strong antimicrobial activity against Escherichia coli, Staphylococcus aureus and Botrytis cinerea. Then, to investigate the antioxidant capacity of FSBJ, we used H₂O₂ to induce oxidative stress in C2C12 cells and assessed the protection conferred by FSBJ to damaged cells. It was discovered that after 24 h of treatment with FSBJ, not only was there an increase in the activities of intracellular SOD and glutathione peroxidase (GSH-Px), but also a reduction in reactive oxygen species (ROS) content, catalase (CAT) activity, and malondialdehyde (MDA) content. This research lays the theoretical groundwork and provides reference materials for the improved fermentation of sea buckthorn and demonstrates its resulting antioxidant effect.

Effects of Dietary Supplementation of Pomegranate Peel with Xylanase on Egg Quality and Antioxidant Parameters in Laying Hens

Pomegranate contains bioactive compounds in all its parts. In this study, two levels of pomegranate peel byproduct (PPB) with or without the inclusion of xylanase enzyme were used to supplement laying hens' diet, in a 2 × 2 full factorial design. A total of 48 Isa brown laying hens were fed the following experimental diets for 8 weeks: T1 (2.5% PPB); T2 (2.5% PPB and xylanase); T3 (5% PPB); T4 (5% PPB and xylanase). Eggs collected were analyzed for egg quality parameters. Moreover, egg yolks were analyzed for Malondialdehyde content (MDA), fatty acid profile and total phenolic content. The T2 eggs showed enhanced yolk coloration and greater yolk total phenolic content. The T3 and T4 egg yolks showed lower MDA levels compared with T1, T2. Overall, results have shown that (a) xylanase inclusion affected egg yolk coloration and total phenolic content when combined with 2.5% PPB dietary supplementation; (b) dietary supplementation of 5% PPB resulted in eggs with reduced MDA levels.

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.

The Therapeutic Alliance between Pomegranate and Health Emphasizing on Anticancer Properties

Pomegranate is a fruit bearing-plant that is well known for its medicinal properties. Pomegranate is a good source of phenolic acids, tannins, and flavonoids. Pomegranate juice and by-products have attracted the scientific interest due to their potential health benefits. Currently, the medical community has showed great interest in exploiting pomegranate potential as a protective agent against several human diseases including cancer. This is demonstrated by the fact that there are more than 800 reports in the literature reporting pomegranate's anticancer properties. This review is an update on the research outcomes of pomegranate's potential against different types of human diseases, emphasizing on cancer. In addition, perspectives of potential applications of pomegranate, as a natural additive aiming to improve the quality of animal products, are discussed.

The Temperature Influence on Drying Kinetics and Physico-Chemical Properties of Pomegranate Peels and Seeds

Pomegranate is a fruit desirable for its nutritional and medicinal properties which has a great industrial potential that is yet under-explored. Notable for its integral use, the peels are used in medicinal infusions and the seeds consumed without restrictions. In this sense, the objective of this work is to determine the drying kinetics of pomegranate peels and seeds in a hot air circulation oven, at temperatures of 50, 60, and 70 °C, adjust mathematical models to experimental data, determine the effective diffusivities and thermodynamic properties of the process and the physicochemical characteristics of peels and seeds of fresh pomegranates and in their flours. Twelve models were used to adjust the drying kinetics, obtaining better results with the Diffusion Approximation model, Verma, and modified Henderson and Pabis. The effective diffusivities were well represented by an Arrhenius equation, with activation energies of 31.39 kJ/mol for seeds and 10.60 kJ/mol for peels. In the drying process, the seeds showed higher values of enthalpy, entropy, and Gibbs free energy concerning peels. Pomegranate peel and seed flours have proximal composition and distinct physicochemical characteristics, with high fiber, carbohydrate, and energy content. In addition, peel flours stand out for their mineral content, and seed flours do for their lipid and protein content.

Effects of natural antioxidants and high-energy fabrication methods on physical properties and oxidative stability of flaxseed oil-in-water nanoemulsions

The effects of high-energy fabrication methods, namely high-pressure homogenization (HPH) and ultrasonication (US), on physicochemical properties of flaxseed oil-in-water nanoemulsions (FNEs) containing clove essential oil (CEO) and/or pomegranate peel extract (PPE) were studied during storage at 4 and 25 °C. Nanoemulsions with relatively similar average droplet size were prepared by HPH and/or US. An increase in droplet size was observed over time. Lower storage temperature and fabrication by US increased Ostwald ripening rate. Higher storage temperature and fabrication by US decreased the centrifugal stability of nanoemulsions. CEO revealed better antioxidant properties than PPE. The oxidative stability was evaluated by determining secondary oxidation products, and fatty acids profile. The absence of antioxidant, fabrication by US, and higher storage temperature decreased the oxidative stability of nanoemulsions. The results of this study might be helpful in controlling the oxidation of FNEs during long-term storage and in designing functional foods and beverages.

Physical, Chemical, and Antioxidant Characterization of Nano-Pomegranate Peel and Its Impact on Lipid Oxidation of Refrigerated Meat Ball

Pomegranate peel (CPP), enriched with bioactive constituents, had potent antioxidant features. Therefore, it is worth finding out functional and antioxidant features of the nanoscale pomegranate peel. The nanoscale of pomegranate peel was prepared by ultrafine grinding in a ball mill for 45 min (NPP45) and 90 min (NPP90). The physical (SEM, TEM, FTIR, and XRD) and chemical characteristics (phenolics, flavonoids, DPPH scavenging activity, FRAP, and reducing power) of nanoparticles were studied. The quality aspects of cold stored (5 ± 2°C) meatballs formulated with 0.5% (W/W) of nano-peel powder were evaluated. Similarly, FTIR spectra and XRD patterns were recorded for nano and crude pomegranate peel samples. Generally, grinding the crude peel for 45 and 90 min enhanced its scavenging activity, reducing power, FRAP, total phenolic, and flavonoid by a range of 12.58 to 20.37 and 20.57% to 35.18%, respectively. The addition of crude/nanosized peel to the meat ball diminish ( $p<0.05$ ) formation of thiobarbituric acid (TBARS), peroxide (PV), and volatile nitrogen and kept the sensory attributes up to 9 days of cold storage. No significant differences were noticed in PV and TBARS of meatballs formulated with 0.5% NPP90 and 0.1% BHT, which suggests the potential use of nanoscale pomegranate peel as natural substitutes to BHT in meat products.

Antibacterial activity and chemical characterization of almond (Prunus dulcis L.) peel extract

In this study, almond skin of Prunus dulcis L. variety Casteltermini was characterised for its chemical composition and for the inhibitory activity towards food associated microorganisms belonging to pathogenic (Salmonella Enteritidis, Staphylococcus aureus, Escherichia coli and Listeria monocytgenes), spoilage (Pseudomonas poae and Brochotrix thermospacta) and useful (Levilactobacillus brevis and Saccharomyces cerevisiae) groups. The n-hexane extract of P. dulcis skin, investigated by GC-MS, evidenced linoleic, palmitic, and oleic acids as the main abundant compounds. Staphylococcus aureus ATCC 33862 growth was strongly limited by n-hexane extract and the minimum inhibition concentration (MIC) was 25.5 mg/mL. These results highlight the potential of almond by-products as food bio-preservatives as well as pharmaceutical products.

Pomegranate Peels and Seeds as a Source of Phenolic Compounds: Effect of Cultivar, By-Product, and Extraction Solvent

The nutraceutical properties of Punica granatum L. are not restricted to the edible portion of the fruit but also to the peels and seeds, flowers, leaves, and tree bark. The recovery and valorization of the peel and seeds (ca. 50% of the whole fruit), besides the positive environmental impact, can be viewed as a source of natural bioactive compounds. Thus, the bioactive properties of extracts of pomegranate peel and seeds from Acco and Wonderful known cultivars, as well as of the novel Big Full cultivar, were evaluated. The dried and ground pomegranate by-products were submitted to a conventional solid/liquid extraction with ethanol/water mixtures (0%, 25%, 50%, and 75% of EtOH, v/v). The obtained extracts were characterized in terms of total phenolic compounds (TPC), total flavonoids (TF), and antioxidant activity (AA), determined by the DPPH radical scavenging activity and expressed as IC50 (half maximum inhibitory concentration). With the exception of the Acco cultivar, the extraction yield (EY) was higher for peels, whose extracts showed higher TPC, TF, and IC50 (lower AA). The extracts obtained from the by-products of the Big Full cultivar had a statistically higher overall bioactive potential (TPC: 0.36 mg GAE/mg extract; TF: 0.031 mg CATE/mg extract; IC50: 0.51 mg/mL) compared to the other two studied cultivars. Furthermore, the EY was enhanced by solvents richer in ethanol (50-75%), allowing obtaining extracts richer in TPC and TF with higher AA. Finally, it was shown that EY combined with bioactive data allowed a satisfactory principal component unsupervised differentiation of the pomegranate extracts according to the type of by-product used.

Assessment of physicochemical, functional, thermal, and phytochemical characteristics of refined rice bran wax

The drastic increase in the utilization and conversion of biomass has been an effect of sustainability and circular economy in the food processing sector. Rice bran wax (RBW), an intermediate by-product of rice bran oil refining industries, has been one of the underutilized waste materials. The FT-IR analysis showed that RBW contains many similar compounds to that of beeswax (BW) and carnauba wax (CW). The DSC thermographs showed melting and crystallization temperatures of RBW as 78.55 and 73.43 °C, respectively, lesser than CW and more than BW. The peak profiling of XRD diffractographs has shown full-width at half-maximum of CW and RBW as 0.61 and 0.45, respectively, indicating distortion in crystal formation. The sequential extracts of RBW in hexane, dichloromethane, and ethylacetate have shown antimicrobial activity against E. coli and S. typhi. The research provides a baseline for extraction and separation of specialty compounds from RBW for by-product utilization.

Effect of Antimicrobial and Antioxidant Rich Pomegranate Peel Based Edible Coatings on Quality and Functional Properties of Chicken Nuggets

The current study evaluated the effect of pomegranate peel-based edible coating on chicken nuggets in order to develop a functional and safe product, high in nutritional value. For this purpose, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and total phenolic content (TPC) assays were performed to check the potential antioxidant activity of chicken nuggets; microbial control, including total aerobic count and coliforms population, was performed for quality and safety purposes; and thiobarbituric acid reactive substances (TBARS) and peroxide value (POV) were performed to determine the oxidative stability of chicken nuggets. Different treatments were applied at different storage periods (0th, 7th, 14th and 21st day). The higher value of total aerobic count (5.09 ± 0.05 log CFU/g) and coliforms (3.91 ± 0.06 log CFU/g) were obtained for the uncoated samples, while the lower population was enumerated in the combination of sodium alginate (SA) and pomegranate peel powder (PPP). However, DPPH (64.65 ± 2.15%) and TPC (135.66 ± 3.07 GAE/100 g) values were higher in the coated chicken nuggets (SA (1.5%) and PPP (1.5%)) and lowest in the control samples. The higher value of TBARS (1.62 ± 0.03 MDA/kg) and POV (0.92 ± 0.03 meq peroxide/kg) were observed in the uncoated chicken nuggets. In the Hunter color system, L*, a*, and b* peak values were determined in the coated chicken nuggets with SA (1.5%) + PPP (1.5%) at the 21st day of storage. The uncoated chicken nuggets had different sensory characteristics (appearance, color, taste, texture, and overall acceptability) compared to the coated samples. Conclusively, coating based on the combination of SA (1.5%) and PPP (1.5%) increased the quality, safety, and nutritional properties of chicken nuggets.

Potential use of plant-based by-products and waste to improve the quality of gluten-free foods

The food industry generates a large amount of waste and by-products, the disposal of which has a negative impact on the environment and the economy. Plant-based waste and by-products are rich in bioactive compounds such as dietary fiber, proteins, essential fatty acids, antioxidant compounds, vitamin, and minerals, which can be exploited to reduce the nutritional deficiencies of gluten-free products. The latter are known to be rich in fats and carbohydrates but lacking in bioactive compounds; the absence of gluten also has a negative effect on textural and sensory properties. Several attempts have been made to improve the quality of gluten-free products using alternative flours and additives, or by adopting innovative technologies. The exploitation of plant-based by-products would represent a chance to improve both the nutritional profile and the overall quality of gluten-free foods by further enhancing the sustainability of the agri-food system. After examining in detail the composition of plant-based by-products and waste, the objective of this review was to provide an overview of the effects of their inclusion on the quality of gluten-free products (bread, pasta, cake/muffins, biscuits and snacks). The advantages and drawbacks regarding the physical, sensory, and nutritional properties were critically evaluated. © 2021 Society of Chemical Industry.

Chemical and Biological Properties of Peach Pomace Encapsulates: Chemometric Modeling

Background: Bioactive compounds need to resist food processing, be released from the food matrix, and be bioaccessible in the gastrointestinal tract in order to provide health benefits. Bioactive compounds isolated from peach pomace (PP) were encapsulated using four different wall materials to improve their stability and to evaluate the effects of in vitro gastrointestinal digestion, as well as chemometric modeling among obtained encapsulates. Methods: Phenolics and carotenoids content, antioxidant, antihyperglycemic, anti-inflammatory, and cell growth activities were evaluated after gastric and intestinal digestion steps. Chemometrics classification analysis–principal component analysis and hierarchical cluster analysis revealed grouping among encapsulates. Results: The encapsulation of PP bioactive compounds showed a protective effect against pH changes and enzymatic activities along digestion, and thereby contributed to an increase in their bioaccessibility in gastric and intestinal fluids. Conclusions: The obtained results suggest protein and polysaccharide carriers and the freeze-drying technique, as an efficient method for the encapsulation of bioactives from PP, could find use in the food and pharmaceutical industry.

Effects of Gum Arabic Coatings Enriched with Lemongrass Essential Oil and Pomegranate Peel Extract on Quality Maintenance of Pomegranate Whole Fruit and Arils

The effects of gum arabic coatings combined with lemongrass oil and/or pomegranate peel extract on freshly harvested mature 'Wonderful' pomegranate fruit were studied. Fruit were coated with gum arabic (GA) (1.5% w/v) alone or enriched with lemongrass oil (LM) (0.1% v/v) and/or pomegranate peel extract (PP) (1% w/v). Fruit were packed into standard open top ventilated cartons (dimensions: 0.40 m long, 0.30 m wide and 0.12 m high), and stored for 6 weeks at 5 ± 1 °C (90% RH). Evaluations were made every 2 weeks of cold storage and after 5 d of shelf life (20 °C and 65% RH). Fruit coated with GA + PP (4.09%) and GA + PP + LM (4.21%) coatings recorded the least cumulative weight loss compared to the uncoated control (9.87%). After 6 weeks, uncoated control and GA + PP + LM recorded the highest (24.55 mg CO2Kg-1h-1) and lowest (10.76 mg CO2Kg-1h-1) respiration rate, respectively. Coating treatments reduced the incidence of decay and treatments GA + LM + PP and GA + PP recorded the highest total flavonoid content between 2 and 6 weeks of storage. The findings suggest that GA coatings with/without LM and PP can be a beneficial postharvest treatment for 'Wonderful' pomegranates to reduce weight loss and decay development during cold storage.

The Anti-Inflammatory, Anti-Apoptotic and Antioxidant Effects of a Pomegranate-Peel Extract against Acrylamide-Induced Hepatotoxicity in Rats

The Acrylamide is a toxic compound generated under oxidative stress arising from intracellular ROS production and induced toxicity. It is frequently used in industry and generated through the heating of tobacco and foods high in carbohydrates. The exact mechanism of its toxicity is still unclear. In this study, an extract of the peels of pomegranate (Punica granatum L.), a nutritious and visually appealing fruit with a diverse bioactive profile, was examined for its potential anti-apoptotic, antioxidant, and anti-inflammatory effects. A total of 40 adult male Wistar rats were allocated into four groups of 10 rats each: Group 1 was a negative-control group (CNT) and received normal saline; Group 2 was a positive-control acrylamide group and received acrylamide orally at a dose of 20 mg/kg/bw; in Group 3, the rats were supplemented with pomegranate-peel extract (P.P; 150 mg/kg/bw) orally on a daily basis for 3 weeks, administered simultaneously with the acrylamide treatment described for Group 2; Group 4 was a protective group, and the animals received the pomegranate-peel extract and acrylamide as stated for Groups 2 and 3, with the pomegranate-peel extract (P.P. extract) administered 1 week earlier than the acrylamide. The results indicate that acrylamide exposure increased the serum levels of AST, ALT, creatinine, interleukin-1 beta, and interleukin-6 in an extraordinary manner. In addition, it increased the lipid peroxidation marker malondialdehyde (MDA) and simultaneously weakened antioxidant biomarker activities (SOD, GSH, and catalase) and reduced the levels of interleukin-10. The pomegranate-peel extract was shown to reduce the inflammatory blood markers of interleukin-1 beta and IL-6. Glutathione peroxidase, superoxide dismutase, catalase, and interleukin-10 were all significantly elevated in comparison to the acrylamide-treatment group as a result of the significant reduction in MDA levels induced by the P.P extract. In addition, the pomegranate-peel extract normalized the cyclooxygenase-2 (COX2), transforming growth factor-beta 1 (TGF-β1), and caspase-3 levels, with a significant upregulation of the mRNA expression of heme oxygenase-1 (HO-1), nuclear factor erythroid 2 (Nrf2), and Bcl-2. Therefore, these data reveal that pomegranate peel has anti-inflammatory, antiapoptotic, free-radical-scavenging, and powerful antioxidant activity that protects against acrylamide toxicity.

In Vitro Evaluation of Biological Activities and Phytochemical Analysis of Different Solvent Extracts of Punica granatum L. (Pomegranate) Peels

Antimicrobial resistance is a public health concern resulting in high rates of morbidity and mortality worldwide. Furthermore, a high incidence of food poisoning diseases besides harmful implications of applying synthetic food additives in food preservation necessitates fabrication of safe food preservatives. Additionally, damaging effects of free radicals on human health has been reported to be involved in the incidence of serious diseases, including cancer, diabetes and cardiovascular diseases; hence, finding safe sources of antioxidants is vital. Therefore, the present study was carried out to assess the antibacterial, antiradical and carcinopreventive efficacy of different solvent extracts of pomegranate peels. Agar disk diffusion assay revealed that Staphylococcus aureus, MRSA, E. coli and S. typhimurium were highly susceptible to methanolic fraction of Punica granatum L. peels recording inhibition zones of 23.7, 21.8, 15.6 and 14.7 mm respectively. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the methanolic fraction of Punica granatum L. peels against S. aureus were 0.125 and 0.250 mg/mL, respectively. In addition, the pomegranate acetonic and methanolic fractions revealed an impressive antiradical efficiency against DPPH (2,2-diphenyl-1-picrylhydrazyl) radical recording radical scavenging activity percentages of 86.9 and 79.4%, respectively. In this regard, the acetonic fraction of pomegranate peels revealed the highest anti-proliferative efficiency after 48 h incubation against MCF7 cancer cells recording IC₅₀ of 8.15 µg/mL, while the methanolic extract was highly selective against transformed cancer cells compared to normal cell line recording selectivity index of 5.93. GC-MS results demonstrated that 5-Hydroxymethylfurfural was the main active component of methanolic and acetonic extracts of pomegranate peels recording relative percentages of 37.55 and 28.84% respectively. The study recommends application of pomegranate peel extracts in the biofabrication of safe food preservatives, antioxidants and carcinopreventive agents.

Silk Fibroin and Pomegranate By-Products to Develop Sustainable Active Pad for Food Packaging Applications

In this study, a bio-based polymeric system loaded with fruit by-products was developed. It was based on silk fibroin produced by the silkworm Bombyx mori and pomegranate peel powder, selected as active agent. The weight ratio between fibroin and pomegranate powder was 30:70. Pads also contained 20% w/w of glycerol vs. fibroin to induce water insolubility. Control systems, consisting of only fibroin and glycerol, were produced as reference. Both control and active systems were characterized for structural and morphological characterization (Fourier-transform infrared spectroscopy and optical microscope), antioxidant properties and antimicrobial activity against two foodborne spoilage microorganisms. Results demonstrate that under investigated conditions, an active system was obtained. The pad showed a good water stability, with weight loss of about 28% due to the release of the active agent and not to the fibroin loss. In addition, this edible system has interesting antioxidant and antimicrobial properties. In particular, the pad based on fibroin with pomegranate peel recorded an antioxidant activity of the same order of magnitude of that of vitamin C, which is one of the most well-known antioxidant compounds. As regards the antimicrobial properties, results underlined that pomegranate peel in the pad allowed maintaining microbial concentration around the same initial level (10⁴ CFU/mL) for more than 70 h of monitoring, compared to the control system where viable cell concentration increased very rapidly up to 10⁸ CFU/mL.

Antimicrobial Properties of Lyophilized Extracts of Olive Fruit, Pomegranate and Orange Peel Extracts against Foodborne Pathogenic and Spoilage Bacteria and Fungi In Vitro and in Food Matrices

Several novel antimicrobials with different concentrations of olive, pomegranate, and orange fruit pulp extracts were produced from agricultural byproducts and, after lyophilization, their antimicrobial activity and potential synergistic effects were evaluated in vitro and in food samples against foodborne pathogenic and spoilage bacteria and fungi. The Minimum Inhibitory of the tested bacteria was 7.5% or 10%, while fungi were inhibited at a concentration of 10% or above. The optical density of bacterial and yeast cultures was reduced to a different extent with all tested antimicrobial powders, compared to a control without antimicrobials, and mycelium growth of fungi was also restricted with extracts containing at least 90% olive extract. In food samples with inoculated pathogens and spoilage bacteria and fungi, the 100% olive extract was most inhibitory against E. coli, S. typhimurium, and L. monocytogenes in fresh burger and cheese spread samples (by 0.6 to 1.8 log cfu/g), except that S. typhimurium was better inhibited by a 90% olive and 10% pomegranate extract in burgers. The latter extract was also the most effective in controlling the growth of inoculated fungi (Aspergillus niger, Penicillium italicum, Rhodotorula mucilaginosa) in both yogurt and tomato juice samples, where it reduced fungal growth by 1–2.2 log cfu/g at the end of storage period. The results demonstrate that these novel encapsulated extracts could serve as natural antimicrobials of wide spectrum, in order to replace synthetic preservatives in foods and cosmetics.

Response of two strains of growing Japanese quail (Coturnix Coturnix Japonica) to diet containing pomegranate peel powder

Four hundred and eighty 1-day-old Japanese quail chicks from white and brown strains, 240 birds from each strain, were divided into 4 treatment groups with 6 replicates each (10 birds/replicate). Both strains of quail were fed diets containing 0%, 3%, 6%, and 9% pomegranate peel (PP) powder for a period of 42 days. Results revealed that the final body weight (BW), total feed intake (TFI), body weight gain (BWG), gizzard percentage, and eviscerated carcass weight of white growing quails were significantly (P < 0.05) higher than the brown strain. Quail group fed with 6% PP powder had the highest (P < 0.001) average final BW and BWG (P < 0.001). The dietary PP powder at different levels significantly (P = 0.032) decreased TFI, but had no significant effect on carcass traits except for the liver percentage. Quails fed diet 3% and 9% PP powder had significant (P < 0.001) increased count of immune cells, and improved antioxidant potency. White quails fed diet 3% and 6% PP powder had greater expression of hepatic GHR gene. The expression of hepatic IGF-1 gene was significantly (P < 0.05) higher for brown quails fed diet 6% and 9% PP powder. White quails recorded the highest value of total return (TR). Quails fed diet 6% and 9% PP powder significantly (P < 0.001) recorded higher net return (NR) values. In conclusion, dietary inclusion of PP powder at levels up to 9% for Japanese quail strains improved the growth performance, increased antioxidant properties, enhanced hepatic gene expression, and did not show any adverse influence on carcass quality and blood indices of Japanese quail. Moreover, it increased the NR.

Pomegranate peels waste hydrolyzate optimization by Response Surface Methodology for Bioethanol production

Unwanted agricultural waste is largely comprised of lignocellulosic substrate which could be transformed into sugars. The production of bioethanol from garbage manifested an agreeable proposal towards waste management as well as energy causation. The goal of this work is to optimize parameters for generation of bioethanol through fermentation by different yeast strains while Saccharomyces cerevisiae used as standard strain. The low cost fermentable sugars from pomegranate peels waste (PPW) were obtained by hydrolysis with HNO3 (1 to 5%). The optimum levels of hydrolysis time and temperature were elucidated via RSM (CCD) ranging from 30 to 60 min and 50 to 100 °C respectively. The result shows that optimum values (g/L) for reducing sugars was 61.45 ± 0.01 while for total carbohydrates was 236 ± 0.01. These values were found when PPW was hydrolyzed with 3% HNO3, at 75 °C for one hour. The hydrolyzates obtained from the dilute HNO3 pretreated PPW yielded a maximum of 0.43 ± 0.04, 0.41 ± 0.03 g ethanol per g of reducing sugars by both Metchnikowia sp. Y31 and M. cibodasensis Y34 at day 7 of ethanologenic experiment. The current study exhibited that by fermentation of dilute HNO3 hydrolyzates of PPW could develop copious amount of ethanol by optimized conditions.