Valorization of date palm (Phoenix dactylifera) fruit processing by-products and wastes using bioprocess technology - Review

Supplementation of date palm (Phoenix dactylifera L.) residue for growth and lactic acid production of probiotic bacterial Lactobacillus spp

Date palm is an age-old cultivated plant that thrives in tropical and subtropical regions. The date palm is a bountiful source of carbohydrates, encompassing sucrose, glucose, and fructose and proteins. The date industry generates a significant volume of unused by-products. Dates offer a diverse range of by-products beyond the agri-food sector. LAB have garnered extensive utilisation across diverse food sectors, spanning meat, vegetables, beverages, dairy products, and other fermented foods. In the quest for establishing a new large-scale fermentation process for lactic acid there has been a concerted effort to utilise more cost-effective medium components. In the present work, date palm residue (DPR) derived from date palm fruit, after sugar extraction, was incorporated into MRS. The fermentation process was executed through two distinct fermentation systems. Initially, experiments were conducted in flasks. Afterward, the optimal conditions for bacterial growth were determined, and the experiment was carried out using a bioreactor. DPR supported the probiotic Lactobacillus spp. growth especially after 48 h incubation. The prebiotic effect of DPR on Lactobacillus spp. was reported. An increase in the total number of bacterial populations was observed in response to the addition the DPR until 48 h. Specifically, the supplementing DPR at a concentration of 1.5% in batch fermentation enhanced the growth and lactic acid production of Lactobacillus casei. This study suggests that DPR could potentially function as an economical prebiotic source and could be seamlessly incorporated as a functional food ingredient, thereby transforming a waste product into an economically sustainable food substrate.

Trends and challenges of fruit by-products utilization: insights into safety, sensory, and benefits of the use for the development of innovative healthy food: a review

A significant portion of the human diet is comprised of fruits, which are consumed globally either raw or after being processed. A huge amount of waste and by-products such as skins, seeds, cores, rags, rinds, pomace, etc. are being generated in our homes and agro-processing industries every day. According to previous statistics, nearly half of the fruits are lost or discarded during the entire processing chain. The concern arises when those wastes and by-products damage the environment and simultaneously cause economic losses. There is a lot of potential in these by-products for reuse in a variety of applications, including the isolation of valuable bioactive ingredients and their application in developing healthy and functional foods. The development of novel techniques for the transformation of these materials into marketable commodities may offer a workable solution to this waste issue while also promoting sustainable economic growth from the bio-economic viewpoint. This approach can manage waste as well as add value to enterprises. The goal of this study is twofold based on this scenario. The first is to present a brief overview of the most significant bioactive substances found in those by-products. The second is to review the current status of their valorization including the trends and techniques, safety assessments, sensory attributes, and challenges. Moreover, specific attention is drawn to the future perspective, and some solutions are discussed in this report.

Evaluation of the Phenolic Composition and Biological Activities of Six Aqueous Date (Phoenix dactylifera L.) Seed Extracts Originating from Different Countries: A Comparative Analysis

Date seeds, which are the main by-products of date fruit consumption, were shown to possess promising biological activities and health benefits with minimal human use. The present investigation analyzed and compared the phenolic content of six date seed varieties from four different origins (Khudari, Sakai, and Safawi from Saudi Arabia, Majdool from Jordan, Zahdi from Iraq, and Kabkab from Iran). The aqueous extracts were examined for possible antioxidant, antibacterial, and anti-tumor potential. Date seed oil was extracted, and fatty acid profiles were compared. The results revealed that date seeds are a rich source of polyphenols, which have been linked to biological activities. Furthermore, the phenolic content seemed highly dependent on the variety, where Kabkab had the highest TPC value (271.2 mg GAE/g DM) while Majdool had the lowest value (63.2 mg GAE/g DM). Antioxidant activities of all varieties were highly correlated with the total phenolic content. The antibacterial investigation demonstrated that the Sakai variety possessed the dominant activity, whereas Majdool showed no activity. The results further indicated the sensitivity of both Staphylococcus aureus and Bacillus cereus, with a stronger effect against B. cereus, while no effect was observed against Gram-negative strains (Salmonella Typhi and Escherichia coli). All varieties were able to decrease colon and lung cancer cell viability, especially Khudari and Sakai, with stronger effects against colon cancer cells. Analysis of date seed oil showed high oleic acid content, especially in Sakai. The findings suggest that date seeds are promising candidates for future pharmaceutical applications as nutraceuticals to help combat certain illnesses, as well as functional foods and natural additives that boost the nutritional value of food products, increase their shelf lives, and improve the overall health of consumers.

Survival of Salmonella enterica and Listeria monocytogenes in date palm paste and syrup at different storage temperatures

This study aimed to investigate the behavior of Salmonella enterica and Listeria monocytogenes in processed date paste and syrup at different temperatures. Commercial products were inoculated with approximately 6 log CFU/mL of S. enterica or L. monocytogenes and stored at 4, 10, and 24°C for 90 days. S. enterica was able to survive in date products until the end of storage at 4°C. At this temperature, numbers decreased by 2.1 log CFU/g in date paste and by 3.4 log CFU/g in date syrup; however, at 10°C, cells were reduced >4.2 log CFU/g and were undetectable by direct plating in date paste or by enrichment (complete elimination) in syrup. Further, at 24°C, complete elimination of S. enterica was achieved in date paste and syrup by 30 and 7 days, respectively. L. monocytogenes numbers decreased by 1.4, 4.4, and >4.6 log CFU/g in date paste stored at 4, 10, and 24°C for 90 days, respectively. In date syrup, numbers of L. monocytogenes decreased to undetectable levels by 50, 14, and 4 days at 4, 10, and 24°C, respectively, by direct plating and complete elimination was observed at 10 and 24°C by 50 and 30 days of storage, respectively. The initial pH values of date paste and syrup were 4.7 and 4.8, respectively, and remained stable until the end of storage except for L. monocytogenes-inoculated syrup. PRACTICAL APPLICATION: Salmonella enterica and Listeria monocytogenes can easily survive in date paste and syrup particularly at refrigerator temperature, which explains the necessity of preventing the contamination of date products with foodborne pathogens.

Characterization analysis of date fruit pomace: An underutilized waste bioresource rich in dietary fiber and phenolic antioxidants

Date fruit pomace (DFP), an abundant byproduct of the date syrup industry, is currently underutilized. It is either fed to animals or landfilled where it ferments, causing serious environmental issues. Proper waste management through valorization strategies is required to reduce the environmental impact of date waste and foster the transition of the date processing industry towards sustainability. The implementation of valorization strategies requires characterizing the DFP composition. Herein, four DFP samples of Emirati varieties were characterized in terms of compositional and functional properties. The fresh DFPs contained moisture (∼60.0 g/100 g). On a dry matter basis, DFPs contained total dietary fiber (∼45.5 g/100 g), residual sugars (∼35.3 g/100 g), protein (∼10.6 g/100 g), ash (∼4.1 g/100 g), and fat (∼1.3 g/100 g). They were also rich in nutritionally important elements such as potassium (∼145.7 ppm), calcium (∼46 ppm), phosphorus (∼28.7 ppm), and magnesium (∼26.7 ppm). The total phenolic content varied from 170 to 260 mg gallic acid equivalents GAE/100 g, making DFP a good source of antioxidants. Scanning electron microscopy measurements revealed the presence of fibrous bundle-like structures, whose thermal stability was confirmed by thermogravimetric analysis, showing the dominance of insoluble over soluble fiber. Higher water- and oil-holding capacities were found for dried desugared pomace. The high fiber, phenolic, and elemental content highlight the high nutritional value of DFP, which can be used as dietary supplement, while its sugar content can be used to produce value-added biochemicals via fermentation. Thus, DFP may represent a valuable bioresource for food and non-food applications.

Optimizing Alternative Substrate for Tomato Production in Arid Zone: Lesson from Growth, Water Relations, Chlorophyll Fluorescence, and Photosynthesis

Soilless culture is considered the mostpromising, intensive, and sustainable approach with various advantages for plant production in terms of saving water and nutrients. It can provide consumers with sufficient and high-quality food. However, the commonly used growing substrate for soilless cultivation, coconut fiber (CF), is usually imported and expensive or even unavailable. The objectives of this study were to investigate the impact of local organic farm resources substrates on tomato (Solanum lycopersicum L.) plant growth, water relations, photosynthesis, chlorophyll fluorescence, and phytochemical analysis of fruits in a hydroponics culture system. Two growth substrates were evaluated: date-palm waste composted with animal manure (7:3 w/w) (DPAM) and date-palm trunk compost (DPT). CF and local soil were utilized as positive and negative controls, respectively, in randomized blocks. The results revealed that DPAM substrate enhanced plant growth and physiology: shoot development, leaves tissues hydration, and photosynthetic parameters, as well as chlorophyll fluorescence. However, DPT and CF improved fruit quality: water, mineral, sugar, and protein content. The antioxidant activity of the fruit extract was the greater in DPAM, reaching 13.8 mg GAEg^-1 DW. This value wasdecreased in soil by 40%. Photosynthesis activity was the most important in DPAM with 12 µmol CO₂ m^-2 s^-1, and only 6.4 µmol CO₂ m^-2 s^-1 in the soil condition. However, regarding the non-photochemical quenching, the dissipated light energy was greater in soil (0.096 ± 0.02) than in DPAM (0.025 ± 0.04). Date-palm waste-based substrates improved tomato vegetative growth and fruit quality as compared to soil-based culture. Date-palm waste-based substrates supplemented with manure appear to be promising and less expensive alternatives to the coconut fiber substrate extensively used in soilless crops in North Africa.

Ameliorative Effects of some Natural Antioxidants against Blood and Cardiovascular Toxicity of Oral Subchronic Exposure to Silicon Dioxide, Aluminum Oxide, or Zinc Oxide Nanoparticles in Wistar Rats

The present study determines the possible protective role of fig fruit extract with olive oil and date palm fruit extract (FOD) in decreasing the oral subchronic blood and cardiovascular toxicity of SiO₂NPs, Al₂O₃NPs, or ZnONPs. The present study used 80 male Wistar rats (8 groups, n = 10) distributed according to the treatment. The FOD treatments were used at their recommended antioxidant doses. All nanoparticles (NPs) were given orally and daily at doses of 100 mg/kg for 75 days. The oral administration of different NPs alone led to dramatic, oxidative stress, inflammatory markers, blood coagulation, endothelial dysfunction markers, myocardial enzymes, hematological parameters, lipid profile, and histopathological features compared with the control group. The FOD-NP-treated groups recorded significantly ameliorated blood and cardiovascular toxicity hazards compared to the groups administered with the NPs alone. In conclusion, the administration of FOD provides considerable chemopreventive and ameliorative effects against NP toxicity.

Chemical Characterization of Date Seeds (Phoenix dactylifera L.) Cultivated in Algeria for its Application as Functional Ingredients

Seven date seeds cultivars, Deglet Nour, Degla Baïdha, Fakht, Ghars, Hamraya, Tafezouin and Takermost were provided from Algerian Sahara. Some of these Algerian date seeds were studied for the first time (Fakht, Hamraya and Takermost). The biochemical characterization of these date seeds were studied, including fatty acids and minerals profiles. The results showed that date seeds are a good source of carbohydrates and crude cellulose, with averages of 66.63 and 13.20%, respectively. They are also a good source of proteins, with the cultivar Deglet Nour seeds as the richest one (9.27 ± 0.03%). The main fatty acid for all date seeds oils is oleic acid except for Deglet Nour in which lauric acid is the main one. However, the studied date seed oils could be classified as oleic-lauric oil. Potassium was the highest mineral in all date seeds cultivars, with values ranging from 2700 to 2900 mg/Kg, followed by sodium and iron. These results indicate that date seeds have good nutritional value with different compositions among cultivars. It could be concluded that date seeds could be considered as a good opportunity for their technological and industrial valorization.

Bioactive properties and untargeted metabolomics analysis of bioaccessible fractions of non-fermented and fermented date fruit pomace by novel yeast isolates

In this study, attempts were made to utilize date by-product (date fruit pomace; DFP). This study aimed to investigate the health-promoting benefits of the fermented and non-fermented DFP before in vitro digestion and after (bioaccessible fraction). Untargeted metabolomic analyses for bioaccessible fractions were performed by UPLC-QTOF. DPPH percentages were 89.7%-90.3%, 90.1%-91.3%, and 90.8%-91.3% in the control, I. orientalis, and P. kudriazevii samples, respectively, before digestion; α-glucosidase inhibition before digestion was 1.9%-24.4%, 16.3%-30.0%, and 21.3%-31.3%, respectively; antimicrobial activities were 6.1%-13.3%, 13.7%-25.7%, and 20.6%-28.0% against E. coli O157:H7 and 2.2%-11.9%, 7.2%-20.7%, and 11.9%-29.2% against L. monocytogenes, respectively. The DPPH scavenging percentages were ∼63% lower in the bioaccessible fraction. The differentially regulated metabolites classes were benzene and derivatives, amino acids, peptides and analogs, organic acids, and phenols. This study revealed that the fermented DFP exhibited higher health properties than control.

The Effect of an Extract and Fractions of Date Pits on Some Plasma Constituents, Reproductive Hormones, and Testicular Histology in Male Mice

Pits of dates (Phoenix dactylifera L.) have numerous nutritional benefits that could have wide-ranging applications. This study aimed to examine the effects of administering three extracts from powdered date pits on some basic physiological parameters, plasma constituents, reproductive hormones, and testicular histology in CD1 male mice. Three groups received doses of 100 mg/kg/day of lyophilized extract, a nonpolar fraction, and a polar fraction of date pits by oral gavage for 28 consecutive days. For the control, one group was administered a 1 mL/kg concentration of distilled water. The three different extracts significantly increased the plasma testosterone level but showed no significant effect on estradiol or luteinizing hormone levels, except for estradiol reduction in the polar extract group. The measured physiological or biochemical parameters or testicular histology also demonstrated no significant differences between the control mice and those mice treated with the three extracts, except for reductions in plasma urea in all extracts and in total protein in the nonpolar extract. Therefore, date pit extracts may potentially be used as a safe and effective dietary supplement. However, further investigation is needed.

Date fruit as a promising source of functional carbohydrates and bioactive compounds: A review on its nutraceutical potential

From the past decade, consumption of ready-to-eat food and ease of access to fast food increased the onset of several diseases. Thus, there is a need to shift the trend from consumption of unhealthy food item to natural and healthy alternatives. In this context, fruits can be considered as functional food, which have ability to provide essential nutrients and bioactive compounds. These compounds when consume in adequate amount would have the potential to lower the onset of diseases. In this regard, Phoenix dactylifera or date fruit is an important source of functional carbohydrates and bioactive compounds for their use as functional foods. The major functional carbohydrate in date fruit are in the form of dietary fiber, such as β-glucan, cellulose and fructans along with other bioactive compounds. Additionally, it is also a good source of other important nutrients such as sugars, minerals, along with minor quantities of proteins and lipids. Due to these functional compounds, date fruit have shown a wide range of pharmaceutical properties such as antioxidant, anti-inflammatory, anti-diabetic, hepatoprotective and anticancer. This review provides latest information regarding functional and nutraceutical carbohydrates of date fruits along-with mechanism of action on different diseases reported in recent years. PRACTICAL APPLICATIONS: This will provide information to food industries for the development of innovative food products by using date fruit. Moreover, bioactive components from date fruit may prove to enhance global health and wellness. However, further research is needed on clinical trials for the development of functional food products by using date fruit for functional foods and pharmaceutical applications.

Date Fruits as Raw Material for Vinegar and Non-Alcoholic Fermented Beverages

Currently, foods and beverages with healthy and functional properties, especially those that claim to prevent chronic diseases, are receiving more and more interest. As a result, numerous foods and beverages have been launched onto the market. Among the products with enhanced properties, vinegar and fermented beverages have a high potential for growth. Date palm fruits are a versatile raw material rich in sugars, dietary fibers, minerals, vitamins, and phenolic compounds; thus, they are widely used for food production, including date juice, jelly, butter, and fermented beverages, such as wine and vinegar. Furthermore, their composition makes them suitable for the formulation of functional foods and beverages. Microbial transformations of date juice include alcoholic fermentation for producing wine as an end-product, or as a substrate for acetic fermentation. Lactic fermentation is also documented for transforming date juice and syrup. However, in terms of acetic acid bacteria, little evidence is available on the exploitation of date juice by acetic and gluconic fermentation for producing beverages. This review provides an overview of date fruit’s composition, the related health benefits for human health, vinegar and date-based fermented non-alcoholic beverages obtained by acetic acid bacteria fermentation.

Green Extraction of Date Palm Fruits via Ultrasonic-Assisted Approach: Optimizations and Antioxidant Enrichments

Background: Green extraction involves using green solvents, such as water, to reduce energy consumption, avoid health and environmental hazards and induce the quality and quantity of the extract. Date palm fruits are a vital source of food and medicinal activities, as they contain a high diversity of phytochemicals, mainly phenolic and flavonoid compounds. The main aim of this study is to investigate the use of water as a green solvent, when assisted by different ultrasonic frequencies, in the extraction of four different cultivars of date palm fruits, by evaluating the phenolic and flavonoid composition as well as the antioxidant capacity of the extract. Methods: Four date palm fruits’ cultivars (Agwa, Anbarah, Khalas, and Reziz) were extracted using conventional methods (by water and ethanol) and by ultrasonic means, using two frequencies, 28 and 40 kHz, and applying temperatures (30, 45, and 60 °C), also measuring extraction times (20, 40, 60 min.). Response surface methodology was used for the statistical analysis, applying three factors (temperature, time, and ultrasonic frequency), four responses (total phenolic content, total flavonoid content, FRAP, and ABTS), and four cultivars (categories). Results: Conventional water extraction obtained minimal phenolic and flavonoid compounds (up to 52% of ethanol extraction). This percent improved to reach 60% when heat was utilized. The application of ultrasonic frequencies significantly enhanced the extraction of phenolics/flavonoids and the antioxidant ability of the extract to nearly 90% and 80%, respectively. The use of 40 kHz ultrasonic power managed to extract more phenolic and flavonoid components; however, the antioxidant capacities of the extract were less than when the 28 kHz power was utilized. Agwa and Khalas demonstrated themselves to be the best cultivars for ultrasonic-assisted extraction, depending on the results of the optimized responses. Conclusion: This study could be implemented in the industry to produce date palm fruits’ enriched extracts with phenolic and flavonoid components and/or antioxidants.

Bioactivity and Pharmacological Potential of Date Palm (Phoenix dactylifera L.) Against Pandemic COVID-19: a Comprehensive Review

A novel coronavirus disease (COVID-19) or severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2), transmitted from person to person, has quickly emerged as the pandemic responsible for the current global health crisis. This infection has been declared a global pandemic, resulting in a concerning number of deaths as well as complications post-infection, primarily among vulnerable groups particularly older people and those with multiple comorbidities. In this article, we review the most recent research on the role of date palm (Phoenix dactylifera L.) fruits (DPFs) to prevent or treat COVID-19 infection. The mechanisms underlying this preventive or therapeutic effect are also discussed in terms of bioactivity potentials in date palm, e.g., antimicrobial, antioxidant, anticancer, anti-diabetic, anti-inflammatory, neuroprotective, and hemolytic potential, as well as prospect against COVID-19 disease and the potential product development. Therefore, it can be concluded that regular consumption of DPFs may be associated with a lower risk of some chronic diseases. Indeed, DPFs have been widely used in folk medicine since ancient times to treat a variety of health conditions, demonstrating the importance of DPFs as a nutraceutical and source of functional nourishment. This comprehensive review aims to summarize the majority of the research on DPFs in terms of nutrient content and biologically active components such as phenolic compounds, with an emphasis on their roles in improving overall health as well as the potential product development to ensure consumers’ satisfaction in a current pandemic situation. In conclusion, DPFs can be given to COVID-19 patients as a safe and effective add-on medication or supplement in addition to routine treatments.

Evaluation of Date Extract on Nerve Conduction Velocity in Male Rats

INTRODUCTION

Neuropathy is a condition in which the Peripheral Nervous System (PNS) is disordered. Studying the effects of antioxidants on the performance improvement of this system is vital. This study aimed to investigate the effects of date extract on Nerve Conduction Velocity (NCV), Distal Motor Latency (DML), and wave height of the sciatic nerve in male rats.

METHODS

This laboratory study used 24 male Wistar rats weighing 250-300 g, divided into the test and control groups. The test group received 10% date extract daily, at 4 mL/kg of body weight, for three weeks. In the beginning, nerve Conduction Velocity (NCV), Distal Motor Latency (DML), and wave height of the sciatic nerve were examined in all animals and reexamined for NCV three weeks later. P-values lower than 0.05 were considered significant.

RESULTS

Sciatic NCV and wave height were significantly increased; however, compared to the control group, DML of the knee significantly declined in the test group.

CONCLUSION

The compositions of date extract accelerate electrical signal transmission.

HIGHLIGHTS

Irreparable damages to the Peripheral Nervous System (PNS) are major problems in societies.Different therapeutic methods have been adopted for peripheral nerve repair.According to FAO, the production and use of dates are rising.Dates are used in traditional medicine for curing hoarseness, paralysis, backache, and rheumatic pains.

PLAIN LANGUAGE SUMMARY

Dates are highly important in our nutrition. There have been studies on the positive antioxidative effects of date extract in preventing diabetic neuropathy. Dates are used in traditional medicine for curing hoarseness, paralysis, backache, and rheumatic pains, among others. The importance of dates is derived from their rich compositions of carbohydrates, salts and minerals, dietary fiber, vitamins, fatty acids, amino acids, and proteins. Different therapeutic methods have been adopted for PNS, still, 50% of these damages become permanent and cause disability. Date palms are in the palm family native to Iran, and found in relatively tropical regions.Dates are used in traditional medicine for curing hoarseness, paralysis, backache, and rheumatic pains, among others. In short, the compositions of date extract accelerate electrical signal transmission.

Surfactants in biorefineries: Role, challenges & perspectives

The use of lignocellulosic biomass (LCB) as feedstock has received increasing attention as an alternative to fossil-based refineries. Initial steps such as pretreatment and enzymatic hydrolysis are essential to breakdown the complex structure of LCB to make the sugar molecules available to obtain bioproducts by fermentation. However, these steps increase the cost of the bioproduct and often reduces its competitiveness against synthetic products. Currently, the use of surfactants has shown considerable potential to enhance lignocellulosic biomass processing. This review addresses the main mechanisms and role of surfactants as key molecules in various steps of biorefinery processes, viz., increasing the removal of lignin and hemicellulose during the pretreatments, increasing enzymatic stability and enhancing the accessibility of enzymes to the polymeric fractions, and improving the downstream process during fermentation. Further, technical advances, challenges in application of surfactants, and future perspectives to augment the production of several high value-added bioproducts have been discussed.

Glycemic response of honey and dates consumption

Background and objective: The current study aims to evaluate the glycemic index of local honey and date intake in healthy adults. Methods: The study was conducted on 24 healthy volunteers. They were given 50 g of carbohydrates from Haji Omeran local honey, Khudri (or Khadrawi) local date and reference food (white bread). The average body mass index and age of volunteers are almost similar. The blood samples were collected from finger capillaries to assess the glucose levels by using glucometer at selected time points (0, 15, 30, 60, 90, and 120 minutes). The data was recorded and statistically analyzed by one-way ANOVA and Duncan comparison. Results: The study results showed that the glycemic index of the honey and date is classified as a medium glycemic index, referring to their high carbohydrates content. The results also indicated that honey and dates have significantly different effects (P<0.05) on the blood glucose responses compared to reference food (white bread) in healthy subjects. The mean blood glucose levels after honey ingestion were higher than that when the date was ingested and lower than that of the reference food. In addition, the blood glucose responses for different foods in the study for females and males are not significantly different (P>0.05). Conclusions: In conclusion, eating behavior regarding honey and date consumption, particularly portion size and ingestion timing, is essential to manage blood glucose levels. Thus, glycemic index values should be considered in promoting a healthy lifestyle from chronic related metabolic disorders especially, diabetes mellitus, cardiovascular disease, and obesity.

Date Components as Promising Plant-Based Materials to Be Incorporated into Baked Goods—A Review

Date (Phoenix dactylifera L. Arecaceae) fruits and their by-products are rich in nutrients. The health benefits of dates and their incorporation into value-added products have been widely studied. The date-processing industry faces a significant sustainability challenge as more than 10% (w/w) of the production is discarded as waste or by-products. Currently, food scientists are focusing on bakery product fortification with functional food ingredients due to the high demand for nutritious food with more convenience. Utilizing date components in value-added bakery products is a trending research area with increasing attention. Studies where the researchers tried to improve the quality of bakery goods by incorporating date components have shown positive results, with several drawbacks that need attention and further research. The objective of this review is to present a comprehensive overview of the utilization of date components in bakery products and to identify gaps in the current knowledge. This review will help focus further research in the area of valorization of date by-products and thereby contribute to the generation of novel functional bakery products that meet consumer expectations and industry standards, thus generating income for the relevant industry and considerable alleviation of the environmental burden this waste and by-products contribute to. Only a few studies have been focused on utilizing date by-products and their extracts for baked goods, while a research area still remaining under-explored is the effect of incorporation of date components on the shelf life of bakery products.

Traditional fermented foods and beverages in Iraq and their potential for large-scale commercialization

The tradition of making fermented foods and beverages in Iraq dates back to 7500 BC. These fermented foods and beverages are represented by meat-, milk-, vegetable-, and fruit-based products reflecting diversity of agricultural production in ancient Iraq (Mesopotamia). Although the recipes for some fermented foods and beverages were lost throughout history, those remaining foods and beverages occupy a noticeable position in modern Iraqi cuisine. In this review, knowledge and techniques for preparation of 5 traditional fermented foods, i.e. Basturma, Smoked Liban,Aushari cheese, Turshi, and Sour Khobz, and 3 fermented beverages, i.e. Shanina, Sharbet Zbeeb, and Erk Sous in Iraq, are documented. Traditional fermented foods and beverages have multiple health benefits because of high content of probiotics and bioactive compounds. Traditional fermented foods and beverages are made using the back-slopping technique which ensures safety of production and maintains organoleptic properties. The review highlights the potential of fermented foods and beverages for their large-scale commercialization.

Enhanced Optimization of Bioethanol Production from Palm Waste Using the Taguchi Method

In the present study, palm fiber (PF) and palm fronds (PFN) were selected as local agricultural wastes for the extraction of different biopolymers (cellulose, hemicelluloses, and lignin) by alkaline sodium hydroxide (PF, 2.37% NaOH at 86.5 °C for 1.6 h; PFN, 6% NaOH at 90 °C for 1 h) and bioethanol production. The processes of extraction were optimized by the experimental design method of Taguchi. The total carbohydrates of PF and PFN obtained were 24.4% and 31.0%, respectively. In addition, the untreated palm fiber (UPF), untreated palm frond (UPFN), cellulose palm fibers (CPF), and cellulose palm fronds (CPFN) were subjected to enzymatic hydrolysis processes using crude enzymes and commercial enzymes at 48 °C and pH 5.5. The results indicate that the maximum reducing sugars used were CPF 229.90, CPFN 243.69, UPF 120.19, and UPFN 100.00 (mg/g), which were obtained at a crude enzyme loading. CPF and CPFN hydrolysates were then successfully converted into bioethanol by a separate enzymatic hydrolysis and fermentation by Saccharomyces cerevisiae. Anaerobic cultivation of the hydrolysates with S.cerevisiae resulted in 0.222 g/g and 0.213 g/g bioethanol in the case of CPF and CPFN, respectively. Optimization processes could be an innovative approach to the sustainable development of bioethanol production.

Utilization of the UAE date palm leaf biochar in carbon dioxide capture and sequestration processes

This paper evaluates the potential use of date palm leaf biochar as a climate change solution through CO₂ capture and sequestration. The pyrolysis of date palm leaf was performed at different temperatures 300°, 400°, 500°, and 600 °C. The physicochemical characteristics of the synthesized biochar were examined using Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray Analysis (EDX), Fourier transforms infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA), and X-ray diffraction analysis (XRD). Direct gas-solid interaction was carried out in an integrated Fluidized Bed Reactor (FBR), connected with a gas analyzer for maximum and effective mixing between the biochar and CO₂. LabView program was used as data acquisition for an instantaneous calculation of CO₂ adsorption. This study showed that the date palm biochar as porous carbon-based materials has high CO₂ adsorption capacity through physisorption and chemisorption progressions. The adsorption results showed a maximum CO₂ capture percentage of 0.09 kg CO₂/kg, 0.15 kg CO₂/kg, 0.20 kg CO₂/kg, and 0.25 kg CO₂/kg palm biochar synthesized at 300 °C, 400 °C, 500 °C, and 600 °C, respectively. This paper paid attention to the inexpensive technology applied in CO₂ sequestration, where fluidization provides well mixing of biochar particles with low operation cost.

Phytoprostanes from Date Palm Fruit and Byproducts: Five Different Varieties Grown in Two Different Locations As Potential sources

Date palm fruit has been considered for centuries as an ancient nutritional constituent in the human diet. Recently, global trade in dates increased at an average that, simultaneously, will be accompanied by an increase in date palm byproducts. Supported by date phytochemicals and their health benefits, the aim of this work is to evaluate for the first time the presence of special metabolites of plant called phytoprostanes (PhytoPs) in five different varieties of the Phoenix dactylifera L. pulps and pits using a microLC-ESI-QTrap-MS/MS methodology. Results obtained showed the interest of using these matrices as potential sources of several PhytoPs (ent-16-B₁-PhytoP; ent-9-L₁-PhytoP; and epimers of ent-16-F_1t-PhytoP and of 9-F_1t-PhytoP). The variation in concentration between different varieties and different DPF parts was also evaluated. Results obtained will help to unravel the biological activities associated with DPF consumption that could be related to these bioactive metabolites.

Anti-Alzheimer's disease potential of Arabian coffee versus Date palm seed extract in male rats

Coffee is among the most commonly consumed beverage all over the world. Studies have increasingly suggested caffeine and coffee as effective therapeutic interventions against Alzheimer's disease (AD). We have therefore utilized the aluminum chloride rat model for AD to compare the influence of moderately caffeinated (Arabian) and decaffeinated (Date palm seed) coffee on cognitive impairment and pathological events in AD. AD rats given Arabian or Date palm seed coffee were protected against memory impairment and had lower serum levels of the abnormal protein (amyloid-beta; Aβ1-42), the central pathogenic contributor to AD, and transforming growth factor-beta (TGF-β). Interestingly, Date palm seed (decaffeinated) coffee seems to provide more pronounced protection against AD than Arabian (moderately caffeinated) coffee as evidenced by the greater decrease in serum Aβ levels. These results suggest a surprising therapeutic potential of moderate caffeine intake in Arabian coffee to ameliorate AD through decreasing serum Aβ levels. However, Date palm seed (decaffeinated) coffee, rich in flavonoids, appears to provide a better AD-modifying ability through a direct reduction of Aβ production. PRACTICAL APPLICATIONS: Consumption of moderately caffeinated Arabian coffee attenuated AD-induced cognitive impairment via its anti-amyloidogenic potential, decreasing Aβ levels. Moreover, intake of decaffeinated Date seed extract, rich in flavonoids, exerted a superior anti-AD potential through a direct reduction of Aβ production. Both of them were also safe and maintained hepatic and renal functions in a rat model of AlCl₃ -induced AD. Further clinical studies are warranted to confirm current results and to recommend the regular drinking of Arabian coffee or Date seed extract as a protective approach to delay AD progression in vulnerable individuals or in early disease stages.

Activated Carbon from Palm Date Seeds for CO2 Capture

The process of carbon dioxide capture and storage is seen as a critical strategy to mitigate the so-called greenhouse effect and the planetary climate changes associated with it. In this study, we investigated the CO₂ adsorption capacity of various microporous carbon materials originating from palm date seeds (PDS) using green chemistry synthesis. The PDS was used as a precursor for the hydrochar and activated carbon (AC). Typically, by using the hydrothermal carbonization (HTC) process, we obtained a powder that was then subjected to an activation step using KOH, H₃PO₄ or CO₂, thereby producing the activated HTC-PDS samples. Beyond their morphological and textural characteristics, we investigated the chemical composition and lattice ordering. Most PDS-derived powders have a high surface area (>1000 m² g⁻¹) and large micropore volume (>0.5 cm³ g⁻¹). However, the defining characteristic for the maximal CO₂ uptake (5.44 mmol g⁻¹, by one of the alkaline activated samples) was the lattice restructuring that occurred. This work highlights the need to conduct structural and elemental analysis of carbon powders used as gas adsorbents and activated with chemicals that can produce graphite intercalation compounds.

Physical Fruit Traits, Nutritional Composition, and Seed Oil Fatty Acids Profiling in the Main Date Palm (Phoenix dactylifera L.) Varieties Grown in Morocco

We investigated fruit physical traits and nutritional value in both seed and flesh in eight Moroccan date palm varieties. The greatest values of weight for whole fruit, flesh, seed, and flesh percentage were found in “Boufgous,” “Agondari,” and “Bouskri.” These two later varieties displayed also their superiority with respect to proximate composition. For fruit flesh, proximate composition, energy value, and reducing capacity ranged as follows: proteins (1.60–3.53%), moisture (5.31–17.31%), ash (2.08–2.50%), lipids (0.32–1.09%), carbohydrates (76.69–90.18%), energy value (338.30–385.89 kcal/100 g), and reducing capacity (100.14–1607.12 mg GAE/100 g). Corresponding values in seeds were as follows: proteins (3.20–5.00%), moisture (1.42–4.14%), ash (1.14–1.50%), lipids (6.30–7.40%), carbohydrates (83.39–85.55%), energy value (417.06–429.51 kcal/100 g), and reducing capacity (1427.71–6843.84 mg GAE/100 g dry weight). Among all minerals (K, Ca, Mg, B, Fe, Cu, Mn, Na, and Zn) found in both fruit parts, K had the highest records for both flesh (12047 mg/kg) and seed (6127.6 mg/kg), followed by Mg and Ca. Seeds lipidic fraction was dominated by monounsaturated fatty acid C18 : 1 (47.5%), followed by saturated fatty acids mostly C12 : 0 (18.0%), C14 : 0 (10.5%), and C16 : 0 (10.6%) and finally polyunsaturated fatty acid C18 : 2 (8.8%). It could be concluded that investigated varieties presented a great importance from a nutritional point of view, and seeds could present important opportunities of valorization.

Definitive Screening Design and Artificial Neural Network for Modeling a Rapid Biodegradation of Date Palm Fronds by a New Trichoderma sp. PWN6 into Citric Acid

Generally, the bioconversion of lignocellulolytics into a new biomolecule is carried out through two or more steps. The current study used one-step bioprocessing of date palm fronds (DPF) into citric acid as a natural product, using a pioneer strain of Trichodermaharzianum (PWN6) that has been selected from six tested isolates based on the highest organic acid (OA) productivity (195.41 µmol/g), with the lowest amount of the released glucose. Trichoderma sp. PWN6 was morphologically and molecularly identified, and the GenBank accession number was MW78912.1. Both definitive screening design (DSD) and artificial neural network (ANN) were applied, for the first time, for modeling the bioconversion process of DPF. Although both models are capable of making accurate predictions, the ANN model outperforms the DSD model in terms of OA production, as ANN is characterized by a higher value of R² (0.963) and validation R² (0.967), and lower values of the RMSE (13.44), MDA (11.06), and SSE (9749.5). Citric acid was the only identified OA as was confirmed by GC-MS and UPLC, with a total of 1.5%. In conclusion, DPF together with T. harzianum PWN6 is considered an excellent new combination for citric acid biosynthesis, after modeling with artificial intelligence procedure.

The Integral Utilization of Date Palm Waste to Produce Plastic Composites

In this work, date palm waste (DPW) stemming from the annual pruning of date palm was used as a reinforcing filler in polypropylene matrix at 20–60 wt.%. Only a grinding process of the DPW has been performed to ensure no residue generation and full utilization. The present work investigates how the DPW use affects mechanical properties and water absorption of the ensuing composite. The effect of the addition of maleated polypropylene (MAPP) as a coupling agent on the composite properties was also studied. It was shown that the reinforcing potential of DPW was strongly dependent on aspect ratio and interface quality. The MAPP addition resulted in a composite with higher strength and stiffness than the neat PP, meaning that DPW behaves as reinforcement. The difference in the reinforcing effect was explained by the change in the quality of the interface between date palm waste and the polypropylene polymeric chain.

Valorization of date juice by the production of lipopeptide biosurfactants by a Bacillus mojavensis BI2 strain: bioprocess optimization by response surface methodology and study of surface activities

Lipopeptides biosurfactants (BioS) are natural surface-active compounds produced by a variety of microorganisms. They have great interest in environmental, biomedical and agro-industrial fields. However their large-scale application and production is limited by the cost of culture media and the low yield of production. Therefore, the improvement of the production yields and the development of efficient and cost-effective bioprocess became of a great interest. In this aim, we applied the response surface method to optimize an economic BioS production by a newly isolated strain Bacillus mojavensis BI2 on date Juice called "Luegmi" as unique carbon and nitrogen source. Using a Box-Bhenken design, we studied the effect of three independent variables on lipopeptide production; Leugmi concentration, Na₂HPO₄ and incubation time. The results of this study showed that Leugmi concentration at 25%, Na₂HPO₄ at 0.1% and incubation time of 24 h were optimal conditions for BioS  production, with a maximum Surface Tension (ST) decreasing capacity of 55% corresponding to 27 mN/m and an Oil Dispersing Activity (ODA) of 30 cm² corresponding to a diameter of 6 cm. Preliminary characterization of the BioS produced on Luegmi by UV-Spectra and Thin Layer Chromatography showed its lipopeptide nature. Physic-chemical characterization of the produced lipopeptide on Leugmi showed its great surface activities and stabilities at different pH, temperature and salts concentration. The results of this study suggested that Leugmi, an agricultural byproducts can be used as a low-cost substrate to enhance the yield of lipopeptide BioS with great surface activities for potential environmental application.

Advanced treatment of effluent extended aeration process using biological aerated filter (BAF) with natural media: modification in media, design and backwashing process

Biological aerated filters (BAFs) have high filtration efficiency due to their tolerance of hydraulic and organic shocks are suitable for the treatment of complex and sanitary wastewater. In this study, for the first time, natural media of date kernel from Bam city was used as the BAF reactor media, with a meshing sand filter separated by a standard metal grid from the natural filter section used at the end of the reactor. This can be considered an innovation in the media and filtration. Aeration in the related reactor with 160 cm height was performed bilaterally as up-flow and continuously by nozzles throughout the reactor media. In this work, the actual effluent of the hospital wastewater treatment plant was employed as the inflow wastewater to the reactor, and its organic and inorganic parameters were measured before and after the treatment by the BAF reactor. The backwashing process was also studied in three ways: bottom backwashing (TB), top backwashing (BB), and top and bottom backwashing (TBBS), to determine the amount of water consumed and to achieve the desired result. According to the results obtained in this study, the removal efficiencies of inorganic and microbial contaminants, amoxicillin and azithromycin were obtained as follows: BOD₅: 98.48%, COD: 92.42%, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\text{NO}}_{3}^{ - }$$\end{document}NO3-: 99.4%, P: 93.3%, Coliforms: 97%, Color: 42.8%, Turbidity: 95%, Sulphate: 30%, TSS: 98.9%, Amoxicillin: 20% and azithromycin: 13%. In the backwashing process, the amount of water consumed in these three TB, BB, and TBBS methods were obtained 300, 164, and 118 L, respectively, So, TBBS method was selected as the optimal method. Based on the results obtained in this study, it is concluded that the BAF process with natural date kernel has a high efficiency in removing organic and inorganic contaminants from hospital wastewater, also the concentration of most of the effluent parameters was less or in accordance with EPA standard.

Date Fruit and Seed in Nutricosmetics

Many recent studies in the field of cosmetics have focused on organically sourced substances. Products made from organic materials are safe, high quality, cruelty-free, and more effective than those made from synthetic materials. Many organic compounds are known to be physiologically active in humans and have an extended storage capacity and long-lasting environmental effects. Agro-industrial waste has recently increased substantially, and the disposal of date palm waste, often performed in primitive ways such as burning, is harmful to the environment. Fruit processing industries generate over 10% of the total date seed waste daily, which could be converted into useful food products. Date fruit and seed are rich in sugar, vitamins, fiber, minerals, and phenolic compounds with antioxidant and anti-inflammatory properties that significantly promote human and animal health. This waste is rich in bioactive compounds and essential oils used in many kinds of food, medicine, and cosmetics. Most active cosmetic ingredients come from natural sources such as fruit, fish, and dairy, and recent research shows that date extract and seed oil help to reduce melanin, eczema, acne, and dry patches, while increasing skin moisture and elasticity. This review details the bioactive compounds and nutraceutical properties of date fruit and seed, and their use as cosmetic ingredients.

Isolation and Characterization of Alpha and Nanocrystalline Cellulose from Date Palm (Phoenix dactylifera L.) Trunk Mesh

Highly pure cellulosic polymers obtained from waste lignocellulose offer great potential for designing novel materials in the concept of biorefinery. In this work, alpha-cellulose and nanocrystalline cellulose were isolated from the date palm trunk mesh (DPTM) through a series of physicochemical treatments. Supercritical carbon dioxide treatment was used to remove soluble extractives, and concentrated alkali pretreatment was used to eliminate the lignin portion selectively to obtain alpha-cellulose in approximately 94% yield. Further treatments of this cellulose yielded nanocrystalline cellulose. The structure–property relationship studies were carried out by characterizing the obtained polymers by various standard methods and analytical techniques such as Fourier transform infrared spectroscopy-attenuated total reflection (FTIR-ATR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), energy dispersive X-ray diffraction (EDX-XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Almost 65% yield of pure cellulose was achieved, out of which 94% is the alpha-cellulose. This cellulose shows good thermal stability and crystallinity. The microscopic analysis of the nanocellulose showed a heterogeneous mix of irregular-shaped particles with a size range of 20–60 nm. The percentage crystallinity of alpha-cellulose and nanocellulose was found to be 68.9 and 71.8, respectively. Thus, this study shows that, this DPTM-based low-cost waste biomass can be a potential source to obtain cellulose and nano-cellulose.

Evaluation of some nutritional quality criteria of seventeen Moroccan dates varieties and clones, fruits of date palm (Phoenix dactylifera L.)

Date fruit is known to be the staple food in the Arab countries. It provides a lot of potential health benefits and can be the essential source of nutrients. The majority of Moroccan varieties are not characterized for their chemical, biochemical and quality properties. The aim of this work was to assess the chemical composition of 17 varieties of Moroccan date fruits (Phoenix dactylifera L.) and to determine their nutritive components. The analysis showed that the dates are rich in sugars (51.80-87.98%), they contain low concentration of proteins (1.09-2.80%) and lipids (0.16-0.39%). The predominant mineral is potassium (1055.26-1604.10 mg/100 g DW). Moreover, they contain high concentrations of malic acid (69.48-495.58 mg/100 g (DW)), oxalic acid (18.47-233.35 mg/100 g DW) and tartaric acid (115.70-484.168 mg/100 g DW). These results suggest that the date fruit are nutritious and can be an excellent source for human nutrition and health benefits.

Dry matter intake, digestibility, nitrogen utilization and fermentation characteristics of sheep fed Atriplex hay-based diet supplemented with discarded dates as a replacement for barley grain

This experiment aimed to investigate the effects of substituting barley grain with discarded dates on intake and digestibility, nitrogen (N) utilization and fermentation characteristics of sheep fed Atriplex hay-based diets. Four Barki sheep (50.9 ± 2.93 kg of body weight (BW)) fitted with rumen cannula were used in a 4 × 4 Latin Square design with 23-day periods. Four isonitrogenous (~140 g crude protein (CP)/kg of dry matter (DM)) experimental diets were formulated with Atriplex hay, and dietary sugar content was increased by replacing barley grain with discarded dates (the proportions of discarded dates in the diet were 0, 93, 187 and 280 g/kg DM). Nutrient intakes were not influenced by diet. Organic matter, CP and neutral detergent fibre digestibility increased (p < 0.05) linearly and DM digestibility tended to increase with increased dates inclusion. Ruminal pH and molar proportion of butyrate increased (p < 0.05) linearly with increasing levels of dates inclusion, whereas ruminal ammonia-N decreased (p < 0.05) linearly. Total volatile fatty acid concentration was unaffected. Microbial protein synthesis (MCP) increased linearly and efficiency of microbial protein synthesis tended to increase as discarded dates increased. Total N intake was not affected by diets whereas, urinary N, urea-N and total N execrations linearly decreased (p < 0.05) with higher amounts of dates in the diets. Blood urea-N tended to decrease with increasing levels of dates. It could be concluded that replacing 100% barley grain with discarded dates as a source of soluble carbohydrates can enhance the utilization of N in Atriplex hay-based diet and consequently improve digestibility and MCP.

Cost-effective production of biocatalysts using inexpensive plant biomass: a review

Enzymes are the complex protein moieties, catalyze the rate of chemical reactions by transforming various substrates to specific products and play an integral part in multiple biochemical cycles. Advancement in enzyme research and its integration with industries have reformed the biotech industries. It provides a superior monetary and ecological exchange to traditional material measures in an efficient and environmentally sustainable manner. The cost-effective production of pure and highly active enzymes is still a challenge for the biocatalyst industries. The use of high purity substrates further raises the cost of a typical biocatalyst. The use of low-cost plant-based biomasses as an enticing and sustainable substrate for enzyme production is the most cost-effective approach to these problems. Given the relevance of biomass as a substrate for enzyme development, this review article focuses on the key source, composition and major enzyme generated using various biomass residues. Furthermore, the difficulties associated with the use of biomass as a substrate and technical developments in this area, are also addressed. The use of waste biomass as a substrate lowers the ultimate cost for the production of biocatalysts while simultaneously reduces the waste burden from the environment.

Valorization and extraction optimization of Citrus seeds for food and functional food applications

Valorization of food byproducts has attracted recently considerable attention. Citrus fruits provide considerable non-edible residues reach 80% in juice production. They are considered agri-wastes to comprise peel, pulp and seeds. Previous investigations have focused on peel and pulp to recover value-added products. The review presents for the first-time phytochemical composition of Citrus seeds' products, i.e., oil and extracts. Fatty acids, phytosterols and tocopherols amounted as the major bioactives in Citrus seeds, in addition to limonoids, dietary fibers and flavonoids. Besides their nutritional values, these chemicals have promising applications including production of biodiesel, food enhancers and antioxidants, especially from mandarin and grapefruit seeds. Optimum conditions of the different Citrus seeds' valorization are discussed to improve extraction yield and lessen environmental hazards of solvent extraction. This review presents the best utilization practices for one of the largest cultivated fruit seeds worldwide and its different applications.

Enhanced Gas Separation Prowess Using Functionalized Lignin-Free Lignocellulosic Biomass/Polysulfone Composite Membranes

Delignified lignocellulosic biomass was functionalized with amine groups. Then, the pretreated lignin-free date pits cellulose and the amine-functionalized-date pits cellulose (0–5 wt%) were incorporated into a polysulfone polymer matrix to fabricate composite membranes. The amine groups give additional hydrogen bonding to those existing from the hydroxyl groups in the date pits cellulose. The approach gives an efficient avenue to enhance the CO₂ molecules’ transport pathways through the membrane matrix. The interactions between phases were investigated via Fourier transformed infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), whereas pure gases (CO₂ and N₂) were used to evaluate the gas separation performances. Additionally, the thermal and mechanical properties of the fabricated composites were tested. The pure polysulfone membrane achieved an optimum separation performance at 4 Bar. The optimum separation performance for the composite membranes is achieved at 2 wt%. About 32% and 33% increments of the ideal CO₂/N₂ selectivity is achieved for the lignin-free date pits cellulose composite membrane and the amine-functionalized-date pits cellulose composite membrane, respectively.

Potential of dates (Phoenix dactylifera L.) as natural antioxidant source and functional food for healthy diet

Date fruit is well known for their taste and concentrated nutritional components. Present study investigated two Omani date varieties i.e., Umsellah and Khalas, related to their physical traits, antioxidant properties, carbohydrates and nutritional values. Results showed that total-phenolic in Umsellah were 62% higher compared to Khalas, i.e., 164.22 and 103.85 mg/100 g. Among antioxidants, gallic acid in both Umsellah and Khalas were 35.77 and 27.41 mg/ 100 g respectively. Caffeic and syringic acid resulted 50% greater in Umsellah compared to Khalas. The ρ-coumaric acid contents in Umsellah and Khalas were 24.94 and 21.69 mg/ 100 g respectively. Total sugar in Umsellah (51.37 g of glucose equivalent / 100 g of dates) was found higher compared to Khalas (44.78 g of glucose equivalent / 100 g of dates). Among nutrients, potassium (K) level is very high (> 450 mg/100 g) in both the varieties with optimum range of other nutrients. For dietary fibers, Umsellah (81.17 g/100 g) reported higher proportion than Khalas (67.35 g/100 g). Overall findings inferred that Umsellah contained greater amount of beneficial individual phenolic and sugar compounds for the nourishment of health than Khalas. Therefore, as high antioxidant and nourished with several nutritional components, Umsellah and Khalas can be well adopted as organic and medicinal diets and can be used for various by-products irrespective of their market value.

Phoenix dactylifera L. Seed Extract Exhibits Antioxidant Effects and Attenuates Melanogenesis in B16F10 Murine Melanoma Cells by Downregulating PKA Signaling

Background: The mode of action of Phoenix dactylifera seed extract in skin care has never been explored. Methods: P. dactylifera L. seeds were extracted by ultrasonic extraction. The antioxidant characteristics of the extract were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-di-(3-ethylbenzthiazoline sulfonic acid) (ABTS⁺) assays and scavenging methods. The total phenolic content, reducing capacity, iron (II) ion-chelation, and intracellular reactive oxygen species (ROS)-scavenging capacities were also investigated. The effects of P. dactylifera L. seed extract on melanogenesis were evaluated spectrophotometrically by a mushroom tyrosinase activity assay, determination of intracellular tyrosinase activity, and melanin content. The expression levels of melanogenesis-related proteins were analyzed by Western blotting. Results: The results revealed that the P. dactylifera L. seed extract exerted apparent antioxidant capacity and significantly decreased intracellular ROS content at concentrations of 0.245 and 0.49 (mg/mL). Furthermore, the extract decreased the expression of melanocortin 1 receptor (MC1R), microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein-1 (TRP1), and tyrosinase-related protein-2 (TRP2), and inhibited melanogenesis in B16F10 cells. Conclusions: Our results revealed that P. dactylifera L. seed extract attenuated melanogenesis in B16F10 cells by downregulating protein kinase A (PKA) signaling pathways. Hence, the extract could be used as a type of skin-whitening agent in skin care products.