Sustainable green extraction of anthocyanins and carotenoids using deep eutectic solvents (DES): A review of recent developments.

Recently, deep eutectic solvents (DES) have been extensively researched as a more biocompatible and efficient alternative to conventional solvents for extracting pigments from natural resources. The efficiency of DES extraction for the anthocyanin and carotenoid can be enhanced by microwave-assisted extraction (MAE) and/or ultrasound-assisted extraction (UAE) techniques. Apart from the extraction efficiency, the toxicity and recovery of the pigments and their bioavailability are crucial for potential applications. A plethora of studies have explored the extraction efficiency, toxicity, and recovery of pigments from various natural plant-based matrices using DES. Nevertheless, a detailed review of the deep eutectic solvent extraction of natural pigments has not been reported to date. Additionally, the toxicity, safety, and bioavailability of the extracted pigments, and their potential applications are not thoroughly documented. Therefore, this review is designed to understand the aforementioned concepts in using DES for anthocyanin and carotenoid extraction.

Valorization of different low-grade date (Phoenix dactylifera L.) fruit varieties: A study on the bioactive properties of polyphenolic extracts and their stability upon in vitro simulated gastrointestinal digestion.

Nowadays, the development of suitable strategies for the management and valorization of agri-food products is one of the most important challenges worldwide. In this context, the current research study aimed to explore a valorization strategy for different varieties (Khalas, Jabri, Lulu, Booman, and Sayer) of low-grade date fruit by extracting polyphenolic compounds and investigating their health-promoting bioactive properties. The generated extracts were comparatively analyzed for their phenolic contents, antioxidant, anti-inflammatory, anti-hemolytic, and enzyme inhibitory activities upon in vitro simulated gastrointestinal digestion (SGID). The total phenolic contents (TPC) ranged from 217.3 to 1846.9 mg GAE/100 g fresh weight. After complete SGID, the TPC remarkably increased from 570.8 mg GAE/100 g fresh weight (undigested), reaching the highest value of 1606.3 mg GAE/100 g fresh weight with the Khalas cultivar. Overall, gastric and complete-SGID-treated extracts exhibited higher antioxidant activities, compared to the undigested extracts for the five selected date varieties. Similarly, the gastric and complete SGID promoted the release of bioactive components endowed with significantly higher inhibition levels towards digestive enzymes related to diabetes. Moreover, extracts from all varieties revealed an increase in the inhibition of lipidemic-related enzymatic markers and anti-inflammatory activities when subjected to the gastric digestion phase, which decreased after complete SGID. Principal component analysis (PCA) suggested that higher bioactive properties were influenced by the TPC present in the samples. Overall, low-quality dates could be considered as a potential source of bioactive polyphenols with interesting nutraceutical properties, released upon their transit through the gastrointestinal tract.

Novel Plant-Protein (Quinoa) Derived Bioactive Peptides with Potential Anti-Hypercholesterolemic Activities: Identification, Characterization and Molecular Docking of Bioactive Peptides.

Hypercholesterolemia remains a serious global public health concern. Previously, synthetic anti-hypercholesterolemic drugs were used for ameliorating this condition; however, long-term usage presented several side-effects. In this regard, natural products as an adjunct therapy has emerged in recent times. This study aimed to produce novel bioactive peptides with anti-hypercholesterolemic activity (cholesterol esterase (CEase) and pancreatic lipase (PL)) from quinoa protein hydrolysates (QPHs) using three enzymatic hydrolysis methods (chymotrypsin, protease and bromelain) at 2-h hydrolysis intervals (2, 4, and 6 h). Chymotrypsin-generated hydrolysates showed higher CEase (IC50: 0.51 mg/mL at 2 h) and PL (IC50: 0.78 mg/mL at 6 h) inhibitory potential in comparison to other derived hydrolysates and intact quinoa proteins. Peptide profiling by LC-MS QTOF and in silico interaction with target enzymes showed that only four derived bioactive peptides from QPHs could bind in the active site of CEase, whereas twelve peptides could bind in the active site of PL. Peptides QHPHGLGALCAAPPST, HVQGHPALPGVPAHW, and ASNLDNPSPEGTVM were identified to be potential CEase inhibitors, and FSAGGLP, QHPHGLGALCAAPPST, KIVLDSDDPLFGGF, MFVPVPH, and HVQGHPALPGVPAHW were identified as potential PL inhibitors on the basis of the maximum number of reactive residues in these bioactive peptides. In conclusion, QPHs can be considered as an alternative therapy for the treatment of hypercholesterolemia.

A comparative analysis of anti-lipidemic potential of soybean (Glycine max) protein hydrolysates obtained from different ripening stages: Identification, and molecular interaction mechanisms of novel bioactive peptides.

This study aims to investigate the potentials of mature (MSPHs) and young (YSPHs) soybean enzymatic protein hydrolysates for the inhibition of pancreatic lipase (PL) and cholesterol esterase (C-Ease) enzymes. Higher proteins degradation levels were recorded with Bromelain compared to Flavourzyme and Alcalase, and upon hydrolysis, improved PL and C-Ease inhibition performances were displayed compared to unhydrolyzed proteins. Afterwards, six PHs with potent anti-lipidemic activities were selected for sequencing using LC-MS QTOF and molecular binding studies. Peptides FPFPRPPHQ, QCCAFEM, FAPEFLK from MSPHs and SFFFPFELPRE, FMYL, PFLL, FPLL, LPHF from YSPHs were predicted to possess potent inhibitory activities against PL. Furthermore, FPFPRPPHQ, FMYL, MMLM from MSPHs, and SFFFPFELPRE from YSPHs were predicted to be potent inhibitors of C-Ease. FPFPRPPHQ and SFFFPFELPRE derived from MSPHs and YSPHs, respectively, demonstrated effective inhibition potentialities against both PL and C-Ease. Therefore, mature and young soybean-derived protein hydrolysates could be recognized as a potential ingredient in the management of hypercholesterolemia.

Utilization of diverse protein sources for the development of protein-based nanostructures as bioactive carrier systems: A review of recent research findings (2010-2021).

Consumer awareness of the relationship between health and nutrition has caused a substantial increase in the demand for nutraceuticals and functional foods containing bioactive compounds (BACs) with potential health benefits. However, the direct incorporation of many BACs into commercial food and beverage products is challenging because of their poor matrix compatibility, chemical instability, low bioavailability, or adverse impact on food quality. Advanced encapsulation technologies are therefore being employed to overcome these problems. In this article, we focus on the utilization of plant and animal derived proteins to fabricate micro and nano-particles that can be used for the oral delivery of BACs such as omega-3 oils, vitamins and nutraceuticals. This review comprehensively discusses different methods being implemented for fabrications of protein-based delivery vehicles, types of proteins used, and their compatibility for the purpose. Finally, some of the challenges and limitations of different protein matrices for encapsulation of BACs are deliberated upon. Various approaches have been developed for the fabrication of protein-based microparticles and nanoparticles, including injection-gelation, controlled denaturation, and antisolvent precipitation methods. These methods can be used to construct particle-based delivery systems with different compositions, sizes, surface hydrophobicity, and electrical characteristics, thereby enabling them to be used in a wide range of applications.

Multifunctional bioactive properties of hydrolysates from colocynth (Citrullus colocynthis) seeds derived proteins: Characterization and biological properties.

Citrullus colocynthis (Colocynth) has gained a great deal of interest in their applications as indigenous nutraceutical and as a functional food ingredient. The intact colocynth seed protein was enzymatically hydrolyzed using proteolytic enzymes (alcalase, bromelain, and chymotrypsin) at different time intervals of 3, 6, and 9 h. The highest degree of hydrolysis (87.82%) was observed in chymotrypsin derived colocynth seed protein hydrolysates (CSPH) for 9 h. The CSPHs was further investigated through in-vitro assay to explore its potential biological activity such as antioxidant, inhibition of enzymatic marker related to diabetes (DPP-IV, α-glucosidase and α-amylase) and hyperlipidaemia (cholesteryl esterase and pancreatic lipase). Chymotrypsin hydrolysate showed the strongest DPPH (65.7 mM TEAC) and ABTS (525.2 mM TEAC) radical scavenging activity after 6 h of hydrolysis. Moreover, chymotrypsin-treated CSPH for 6 h inhibited cholesteryl esterase (IC50 = 13.68 µg/mL) and pancreatic lipase (IC50 = 14.12 µg/mL) significantly when compared to native protein. Whereas, bromelain and alcalase treated hydrolysate for 6 h effectively inhibited α-glucosidase and α-amylase at an inhibitory concentration of IC50 = 13.27 µg/mL and of IC50 = 17 µg/mL. Overall, the findings indicated that protein hydrolysates exhibited superior biological activity than intact colocynth seed proteins isolate (CSPI) and could be a sustainable source of bioactive peptides.

Nutraceutical and bioactive potential of high-quality date fruit varieties (Phoenix dactylifera L.) as a function of in-vitro simulated gastrointestinal digestion.

The present study aims to investigate the digestive process (gastric and intestinal phases) effects on the survivability of total and individual phenolic compounds, and the in vitro health-related bioactive properties of four high-quality and commonly consumed dates (Phoenix dactylifera) varieties (Safawi, Khalas, Khudri, and Booman). Phenolic compounds were analyzed by HPLC-UV (at 275 nm) and a higher amount of phenolics were identified in Khalas and Booman intestinal digested extracts, compared to the other date varieties-based extracts, which corroborates with the total phenolic contents in those samples, with respective values of 186.5 and 358.14 mg GAE/100 g. Considering their bioactive potentialities, the highest DPPH radical scavenging activities, of around 320 TEAC µg/mL, were observed with Khalas and Khudri gastric extracts. In contrast, Khalas intestinal extract displayed the highest ABTS radical scavenging potential of 969 TEAC µg/mL. Moreover, the Safawi intestinal extract, along with Khalas and Booman gastric extracts, showed the highest increase in the α-glucosidase inhibition activity, compared to the other date varieties-based extracts. Safawi and Khalas intestinal extracts displayed the highest DPP-IV inhibition activities (IC50 of 2.85 µg/mL). Additionally, regarding the pancreatic lipase and cholesterol esterase inhibition, Khudri and Khalas varieties after intestinal digestion demonstrated the highest activities. These results suggested that the Khalas variety showed more potent bioactive properties than other date varieties, mainly related to the variations in the phenolic content between date varieties. Overall, this study provides additional insight into investigating these dates varieties upon their simulated gastro-intestinal digestion and exhibition of multifunctional bioactive properties.

A novel strategy for producing nano-particles from date seeds and enhancing their phenolic content and antioxidant properties using ultrasound-assisted extraction: A multivariate based optimization study.

Date seeds from the date palm fruit are considered as a waste and they are known to contain several bioactive compounds. Producing nanoparticles from the date seeds can enhances their effectiveness and their utilization as novel functional food ingredients. In this study, date seed nanoparticles (DSNPs) synthesized using acid (HCl) hydrolysis method (HCl concentration of 38% and hydrolysis time of 4 days) was found to have particle size between 50 and 150 nm. The obtained DSNPs were characterized by measuring particle size and particle charge (Zetasizer), morphology using scanning electron microscope (SEM), and determination of the functional groups using fourier-transform infrared spectroscopy (FTIR). DSNPs were further treated with green extraction technology [ultrasound-assisted extraction (UAE)] using water-based and methanol-based solvent for optimizing the extraction of the bioactive compounds by implementing response surface methodology (RSM). The UAE of DSNPs were analysed for set of responses including total phenolic content (TPC), total flavonoid content (TFC), 1,1-diphenyl-2-picrlthydrazyl (DPPH) radical scavenging activity, ferric ion reducing antioxidant power (FRAP), and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity. Three-factor and four-factor Box-Behnken design (BBD) of three models (Synthesis of DSNPs, UAE with water, and UAE with methanol) was performed. The results showed that in UAE of DSNPs using water-based solvent, the key independent factors effecting the TPC and TFC and antioxidant activities were S:L ratio (40:1 mg/ml) and treatment time (9 min). Whereas the methanol-based UAE of DSNPs was mostly affected by US amplitude/power (90%) and methanol concentration (80%). All models were further optimized using response optimizer in Minitab and the generated predicted values were very comparable to the actual obtained results which confirm the significance and validity of all RSM models used. The phenolic compounds identified from DSNPs consisted mainly of 3,4-Dihydroxy benzoic acid, ferulic acid, and p-coumaric acid. The present study demonstrated a successful method for synthesising DSNPs as well as documented the optimum UAE conditions to maximize the extraction of polyphenolic compounds from DSNPs and enhancing their antioxidant activities to be used in food application.

A state-of-art review on camel milk proteins as an emerging source of bioactive peptides with diverse nutraceutical properties.

The generation of camel milk derived bioactive peptides (CM-BAPs) have started to grab keen interest of many researchers during the past decade. CM-BAPs have shown more significant bioactive properties in comparison to camel milk intact proteins. CM-BAPs can be obtained using enzyme hydrolysis to form hydrolysates, or by the fermentation process. In this systematic review, 46 research articles exploring the health-related bioactive properties of CM-BAPs through in-vitro and in-vivo studies have been included. CM-BAPs have been reported for their antioxidant, anti-diabetic, anti-obesity, antihypertensive, antibacterial, antibiofilm, anticancer, anti-inflammatory, anti-haemolytic, and anti-hyperpigmentation activities. The effects of factors such as molecular weight of peptides, type of enzyme, enzyme to substrate ratio, hydrolysis temperature and duration have been analysed. The in-vitro studies have provided enough evidence on certain aspects of the pharmacological actives of camel milk bioactive peptides. Nevertheless, the in-vivo studies are very limited, and no clinical studies on CM-BAPs have been reported.

Fish protein hydrolysates as a health-promoting ingredient-recent update.

Dietary habits and lifestyle-related diseases indicate that food has a direct impact on individual health. Hence, a diet containing essential nutrients is important for healthy living. Fish and fish products are important in diets worldwide because of their nutritional value, especially their easily digestible proteins with essential amino acids. Similarly, fish protein hydrolysate (FPH) obtained from fish muscle and by-products has been reported to exhibit various biological activities and to have functional properties, which make FPH a suitable nutraceutical candidate. This review focuses on the health-promoting ability of FPH in terms of skin health, bone and cartilage health, blood lipid profile, and body-weight management studied in rats and human model systems. The absorption and bioavailability of FPH in humans is discussed, and challenges and obstacles of FPH as a functional food ingredient are outlined.

Identification and characterization of cholesterol esterase and lipase inhibitory peptides from amaranth protein hydrolysates.

Human diet is undergoing a shift towards plant-based diet as a sustainable source of protein compared to animal-derived protein. In this study, cholesterol esterase (CEase) and pancreatic lipase (PL) inhibitory activities of amaranth protein hydrolysates (APHs) were studied. Bromelain, chymotrypsin, and actinase E were used for generating APHs at 2, 4 & 6 h of hydrolysis. Higher PL inhibiting potential were observed in bromelain-derived APHs (IC50 = 0.38-0.66 mg/mL) in comparison to intact amaranth proteins (IC50 = 3.93 mg/mL). Bromelain-4 h hydrolysates (AB4) demonstrated significant inhibitory potential for both CEase (IC50 = 0.47 mg/mL) and PL (IC50 = 0.48 mg/mL) activity. Peptide identification in AB-4 hydrolysate revealed that among 17 bioactive peptides, three peptides (FPFPPTLGY, FGAPR, and FPFVPAPT) were predicted as potential PL inhibitors and only one peptide (FPFVPAPT) was predicted as CEase inhibitor based on the number of substrate binding sites on active site of the enzymes. This is the first study providing insights into amaranth protein derived bioactive peptide possessing CEase and LIP inhibitory potential.

Recent developments in emerging technologies for beetroot pigment extraction and its food applications.

Beetroot is well known for its deep red-purple colouring pigments called betalains. Betalains also found its application in the preparation of functional foods and drinks. Therefore, extraction of pigments with higher recovery and stability is the prime need for the industry. Conventional extraction techniques such as maceration, grinding or pressing have reported low yield of betalains and required large volume of solvent and energy. On the other hand, emerging technologies such as ultrasound, microwave and pulse electric field techniques are highly efficient processes and can achieve higher recovery. In this regard, this review provides an in-depth discussion on the various extraction methods and factors affecting the stability of betalains using conventional and emerging technologies. The recent applications of pigments in various food systems are also presented. Finally, challenges and future prospects of extraction and application of beetroot pigment have been identified and discussed.

Degradation of myofibrillar, sarcoplasmic and connective tissue proteins by plant proteolytic enzymes and their impact on camel meat tenderness.

Inside round muscles (Adductor) from camels treated with bromelain or ficin or papain at 50 or 100 ppm were subsequently stored at 4 °C for 4 days to study the impact on quality attributes, protein degradation and textural changes. Results revealed that papain (100 ppm) treated camel meat showed higher drip loss and lower water holding capacity compared to other treatments. Total protein, sarcoplasmic protein solubility, trichloroacetic acid (TCA)-soluble peptides and soluble collagen were higher in papain and bromelain treated samples at 100 ppm compared to other treatments. Electrophoretic profile of whole camel meat, isolated sarcoplasmic and myofibrillar proteins depicted a noticeable degradation of various proteins in enzyme treated samples, with papain and bromelain (100 ppm) displaying pronounced effect. Meat treated with papain at 100 ppm displayed lower hardness and shear force (P < 0.05). Thus, enzymes treatment at 100 ppm displayed good potential to tenderize camel meat with the papain being more effective among all.

Characterization and identification of novel antidiabetic and anti-obesity peptides from camel milk protein hydrolysates.

In-vitro inhibitory properties of peptides released from camel milk proteins against dipeptidyl peptidase-IV (DPP-IV), porcine pancreatic α-amylase (PPA), and porcine pancreatic lipase (PPL) were studied. Results revealed that upon hydrolysis by different enzymes, camel milk proteins displayed dramatic increase in inhibition of DPP-IV and PPL, but slight improvement in PPA inhibition was noticed. Peptide sequencing revealed a total of 20 and 3 peptides for A9 and B9 hydrolysates respectively, obtained the score of 0.8 or more on peptide ranker and were categorized as potential DPP-IV inhibitory peptides. KDLWDDFKGL in A9 and MPSKPPLL in B9 were identified as most potent PPA inhibitory peptide. For PPL inhibition only 7 and 2 peptides qualified as PPL inhibitory peptides from hydrolysates A9 and B9, respectively. The present study report for the first time PPA and PPL inhibitory and only second for DPP-IV inhibitory potential of protein hydrolysates from camel milk.

Camel milk protein hydrolysates with improved technofunctional properties and enhanced antioxidant potential in in vitro and in food model systems.

Camel milk protein hydrolysates (CMPH) were generated using proteolytic enzymes, such as alcalase, bromelain, and papain, to explore the effect on the technofunctional properties and antioxidant potential under in vitro and in real food model systems. Characterization of the CMPH via degree of hydrolysis, sodium dodecyl sulfate-PAGE, and HPLC revealed that different proteins in camel milk underwent degradation at different degrees after enzymatic hydrolysis using 3 different enzymes for 2, 4, and 6 h, with papain displaying the highest degradation. Technofunctional properties, such as emulsifying activity index, surface hydrophobicity, and protein solubility, were higher in CMPH than unhydrolyzed camel milk proteins. However, the water and fat absorption capacity were lower in CMPH compared with unhydrolyzed camel milk proteins. Antioxidant properties as assessed by 2,2-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activities and metal-chelating activity were enhanced after hydrolysis, in contrast to ferric-reducing antioxidant power which showed a decrease after hydrolysis. The CMPH were also tested in real food model systems for their potential to inhibit lipid peroxidation in fish mince and grape seed oil-in-water emulsion, and we found that papain-produced hydrolysate displayed higher inhibition than alcalase- and bromelain-produced hydrolysates. Therefore, the CMPH demonstrated effective antioxidant potential in vitro as well as in real food systems and showed enhanced functional properties, which guarantees their potential applications in functional foods. The present study is one of few reports available on CMPH being explored in vitro as well as in real food model systems.

Identification of novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides in camel milk protein hydrolysates.

Nine novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides (FLQY, FQLGASPY, ILDKEGIDY, ILELA, LLQLEAIR, LPVP, LQALHQGQIV, MPVQA and SPVVPF) were identified in camel milk proteins hydrolysed with trypsin. This was achieved using a sequential approach combining liquid chromatography tandem mass spectrometry (LC-MS/MS), qualitative/quantitative structure activity relationship (QSAR) and confirmatory studies with synthetic peptides. The most potent camel milk protein-derived DPP-IV inhibitory peptides, LPVP and MPVQA, had DPP-IV half maximal inhibitory concentrations (IC50) of 87.0 ±â€¯3.2 and 93.3 ±â€¯8.0 µM, respectively. DPP-IV inhibitory peptide sequences identified within camel and bovine milk protein hydrolysates generated under the same hydrolysis conditions differ. This was linked to differences in enzyme selectivity for peptide bond cleavage of camel and bovine milk proteins as well as dissimilarities in their amino acid sequences. Camel milk proteins contain novel DPP-IV inhibitory peptides which may play a role in the regulation of glycaemia in humans.

Medicinally active principles analysis of Tephrosia apollinea (Delile) DC. growing in the United Arab Emirates.

BACKGROUND: Tephrosia apollinea is a leguminous plant and is native to southwest Asia, Arabia, northwestern India and northeast Africa. In traditional system, it is used for medicinal and coloring purpose. The present study aims to explore the phytochemical, proximate analysis, element contents and antioxidant potential of T. apollinea extract. METHODS: The phytochemical screening was done with qualitative methods. Proximate analysis and elemental composition were performed from powdered sample. In vitro antioxidant assays such as 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and reducing power-scavenging assays were used for evaluating the antioxidant properties. RESULTS: Qualitative screening of methanolic extract of T. apollinea showed the presence of alkaloids, phenolics, flavonoids, terpenoids, glycosides and saponins. The methanolic extract of T. apollinea exhibited a significant dose dependent inhibition of DPPH activity, with a 50% inhibition (IC50) at a concentration found to be 29.41 µg/ml, which was compared with standard GAE (IC50 = 31.09 µg/ml). The reducing power shows good linear relationship in both standard gallic acid (R2 = 0.956) and T. apollinea extract (0.984). CONCLUSIONS: The results of our study clearly suggested that the methanolic extract of T. apollinea may serve as potential source of natural antioxidant for nutraceutical application.

Retardation of quality changes in camel meat sausages by phenolic compounds and phenolic extracts.

Impact of tannic acid (TA), date seed extract (DSE), catechin (CT) and green tea extract (GTE) on lipid oxidation, microbial load and textural properties of camel meat sausages during 12 days of refrigerated storage was investigated. TA and CT showed higher activities in all antioxidative assays compared to DSE and GTE. Lipid oxidation and microbial growth was higher for control sausages when compared to other samples. TA and CT at a level of 200 mg/kg were more effective in retarding lipid oxidation and lowering microbial count (P < 0.05). Sausages treated with TA and DSE were found to have higher hardness, gumminess and chewiness values compared to other treatments (P < 0.05). Addition of different phenolic compounds or extract did not influence the sensory color of sausages. Furthermore, sensory quality was also found to be superior in TA and CT treated sausages. Therefore, pure phenolic compounds (TA and CT) proved to be more effective in retaining microbial and sensorial qualities of camel meat sausages compared to phenolic extracts (GTE and DSE) over 12 days of storage at 4°C.

Antioxidant activity and inhibitory effects of lead (Leucaena leucocephala) seed extracts against lipid oxidation in model systems.

Antioxidant activity of brown lead (Leucaena leucocephala) seed extracts with and without prior chlorophyll removal was studied in comparison with mimosine. Both extracts showed similar hydroxyl radical (HO(•)) scavenging activity, hydrogen peroxide (H2O2) scavenging activity, singlet oxygen inhibition and hypochlorous acid (HOCl) scavenging capacity (p > 0.05). Nevertheless, the extract without prior chlorophyll removal had higher oxygen radical absorbance capacity than that with prior chlorophyll removal (p < 0.05). Generally, lead seed extracts with and without prior chlorophyll removal possessed a lower antioxidant activity, compared with mimosine. When lead seed extract without prior chlorophyll removal (100 and 200 ppm) was used in different lipid oxidation model systems, including ß-carotene-linoleic acid and lecithin liposome systems, the preventive effect toward lipid oxidation was dose-dependent. At the same level of use, mimosine exhibited a higher efficacy in prevention of lipid oxidation in both systems as indicated by the lower increases in thiobarbituric acid reactive substances. A similar result was obtained in minced mackerel. Therefore, lead seed extract containing mimosine could act as a natural antioxidant to prevent lipid oxidation in foods.

Emerging role of phenolic compounds as natural food additives in fish and fish products.

Chemical and microbiological deteriorations are principal causes of quality loss of fish and fish products during handling, processing, and storage. Development of rancid odor and unpleasant flavor, changes of color and texture as well as lowering nutritional value in fish can be prevented by appropriate use of additives. Due to the potential health hazards of synthetic additives, natural products, especially antioxidants and antimicrobial agents, have been intensively examined as safe alternatives to synthetic compounds. Polyphenols (PP) are the natural antioxidants prevalent in fruits, vegetables, beverages (tea, wine, juices), plants, seaweeds, and some herbs and show antioxidative and antimicrobial activities in different fish and fish products. The use of phenolic compounds also appears to be a good alternative for sulphiting agent for retarding melanosis in crustaceans. Phenolic compounds have also been successfully employed as the processing aid for texture modification of fish mince and surimi. Thus, plant polyphenolic compounds can serve as potential additives for preventing quality deterioration or to retain the quality of fish and fish products.