Walnut Kernels Research Articles

Some Pomological Properties of Promising Seed Propagated Walnut Genotypes from Inner Turkey

In this study, fruits from seed propagated walnut (Juglans regia L.) trees were collected two consecutive years in harvest seasons in Yozgat province in Turkey. Considering two years results, promising five genotypes were determined as cultivar candidate. In the promising genotypes, nut weight ranged from 12.55 (Y11) to 15.08 g (Y15), kernel weight ranged from 5.23 (Y11) to 7.34 g (Y15) and kernel ratio varied between 41.67 (Y11) to 50.84% (Y1), respectively. Linoleic acid was the only polyunsaturated fatty acids and oleic, palmitoleic and gondoic acids determined as major monounsaturated acids ranged from 30.36 to 48.43%, 0.05 to 0.14% and 0.22 to 0.29%, respectively. Propylparaben was the major phenolic acid among the determined phenolic acids in fruits of all five promising genotypes and Y16 had the highest amount of propylparaben (128.08 mg per kg) in its kernel. Malic and tartaric acid were the major organic acids in walnut kernels ranged from 47.88 to 78.51 mg per 100 g and 30.27 to 49.60 mg per 100 g, respectively. L-ascorbic acid was the another organic acids in walnut kernels ranged from 10.71 to 19.71 mg per 100 g. Citric acid was non-determined in kernels of Y1, Y14 and Y15 but determined at kernels of Y11 and Y16 as 4.51 and 7.55 mg per 100 g, respectively. It was determined that the oxalic, malonic, succinic, maleic and fumaric acid contents varied between 8.39-12.08 mg per 100 g, 6.02-9.19 mg per 100 g, 2.86-5.32 mg per 100 g, 0.26-3.00 mg per 100 g and 0.26-0.58 mg per 100 g, respectively.
 
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 In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 4, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue.
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Effects of chitosan coating enriched with thyme essential oil and packaging methods on a postharvest quality of Persian walnut under cold storage

This study evaluated the effects of edible coatings and different packaging methods on the shelf-life and quality of walnut kernels. It focused on the coatings with chitosan (1%) and thyme essential oil (TEO) at concentra-
 
 tions of 500 and 1,000 μl L–1 (CT
 
 , CT
 
 ) or with chitosan alone (CT). The effects of the coatings was assessed
 
 500
 
 1,000
 
 for different packaging methods (LP, loose packaging; PP, packaging in polypropylene bags; and AP, active packa-
 ging) as contrasted to control walnuts (C). Walnuts were stored for 120 days in darkness, with relative humidity of 55%, at 4°C. The results showed that the L* index and moisture content of the samples in the chitosan with 500 and 1,000 μl L–1 thyme essential oil in active packaging were maximum, whereas peroxide and conjugated diene values were minimum. The lowest rate of mold growth was observed for the chitosan samples with 500 μl L–1 thyme es- sential oil in active packaging. The best overall acceptability score was related to the samples with chitosan alone and the chitosan with 500 μl L–1 thyme essential oil in active packaging. The chitosan alone and the chitosan with 500 μl L–1 thyme essential oil in active packaging are recommended for storage of kernels at 4°C.

Increase of walnuts' shelf life using a walnut flour protein-based edible coating

The present study aimed to improve walnut quality during storage. An edible coating was developed from defatted walnut flour and applied to the surface of walnut kernels, which were subsequently stored at 40 °C for 84 days along with walnuts coated with methylcellulose and uncoated kernels. On day 84, the walnuts coated with the walnut flour coating presented the lowest oxidized (13.33) and cardboard (34.73) flavors, the highest walnut flavor (72.27), the highest carotenoid (2.01 mg/kg) and γ-tocopherol contents (306.78 mg/kg) and the least deterioration of oleic/linoleic fatty acids ratio. Furthermore, the kernels covered in this coating displayed higher overall consumers' acceptance than those covered with methylcellulose (5.31). The methylcellulose and walnut flour coatings also prevented against polyunsaturated fatty acids’ deterioration, while walnuts coated with methylcellulose displayed a better behavior for peroxide value. Both coatings protected walnuts against the deterioration processes. Walnut flour coating could be used as a natural alternative to prolong the shelf life of walnut kernels, without the introduction of allergens nor synthetic compounds in this food product.

The effect of microwave and convective dryer with ultrasound pre‐treatment on drying and quality properties of walnut kernel

In this study, the drying kinetics of walnuts was investigated including specific energy consumption (SEC), shrinkage, and walnut kernels' color in two dryers, namely ultrasonic-convection (US-CON) and ultrasonic-microwave (US-MIC). To carry out this study, walnut samples were dried at three MIC powers (270, 450, and 630 W), three input air temperatures (40, 55, and 70°C) and four duration of ultrasonic pre-treatment (0 min (control sample), 10, 20, and 40 min). Fifteen mathematical models were used to describe the walnuts' moisture ratio. The results showed that the Midilli et al. model was the best model for describing the process of drying walnuts in US-CON and US-MIC dryers. Effective moisture diffusivity (Deff) values were calculated to be between 2.77 × 10–9 and 5.56 × 10–9 m2/s for the US-CON dryer and 3.12 × 10–9 to 8.99 × 10–9 m2/s for the US-MIC dryer. The lowest rates of color change were observed in the US-MIC dryer at the lowest microwave power and the lowest duration of ultrasonic pre-treatment. The lowest SEC for the US-CON dryer was 19.52 kWh/kg, and it was 15.90 kWh/kg for the US-MIC dryer. The highest rate of shrinkage was 14.21%, which was seen in the US-CON dryer at the air temperature of 70°C and the duration of ultrasonic pre-treatment of 40 min. According to the results, the best quality of walnut with the lowest changes of color and shrinkage in the microwave dryer was calculated at microwave power 270 W and control sample. Practical applications Drying foods and agricultural products using microwave dryers is a relatively cheap method and has attracted the attention of many researchers today. Also, numerous studies have been conducted on drying agricultural products through microwave and convection dryers with ultrasound pre-treatment. The result of this study could be applied for gathering comprehensive information regarding the drying process (kinetic, Deff, Ea, and SEC) as well as the qualitative properties (color and shrinkage) of walnut kernels dried using the microwave and convective hot air dryers accompanied by ultrasound pre-treatment.

Interaction effects of natural antioxidants coating and various packaging on walnut kernel during storage at 25 °C

Interaction effects of natural antioxidants coating and various packaging on walnut kernel during storage at 25 °C

Effect of high-speed shearing treatment on dehulled walnut proteins

To understand more clearly about true characteristics of walnut protein, dehulled walnut kernels were used to prepare proteins, thus influences of polyphenols on proteins were minimized. Based on solubility, glutelin was found to be the predominant walnut protein (67.64% of total walnut proteins), meanwhile albumin and globulin accounted for 32.29%. SDS-PAGE and two-dimensional electrophoresis results showed that polypeptide profiles for albumin, globulin and glutelin exhibited significant differences. Walnut protein contained major polypeptides of MWs 30–35 kDa (pI 5.5–7.5) and 17–22 kDa (pI 9.0–10.0), along with minor polypeptides of MWs 50–73 kDa (pI 6.0–7.5) and 11–13 kDa (pI about 6.3). Disulfide bonds-linked polypeptides in walnut protein were determined with diagonal electrophoresis, and intermolecular disulfide bonds among polypeptides with MWs 30–34 kDa and 17–22 kDa were dominant. Further analysis by MALDI-TOF/TOF-MS showed that main components of walnut proteins were vicilin and legumin-like proteins. Through high-speed shearing (15,000 rpm) treatment at 60 °C for 5 min, walnut protein solubility were greatly increased from 24.33% to 62.81% at pH 8.0 and from 50.93% to 76.65% at pH 9.0. High-speed shearing treatment, especially at basic pH, could be a better way to improve protein solubility, with decreased particle sizes and more globulin and glutelin solubilized.

DETERMINATION OF SAFETY INDICATORS IN THE DEVELOPED MUFFINS WITH NON-TRADITIONAL RAW MATERIALS

The aim of research is studying the effect of unconventional raw materials (buckwheat, oatmeal, rye, corn, milk whey, skimmed milk powder, propolis, flower pollen, bean powder, sesame oil, pumpkin seed oil, walnut oil, walnut kernels, candied fruit mixes (apple-cherry fruits of bilberries, natural honey with floral pollen, natural honey with propolis) for the quality and safety of new muffins. The article analyzes the results of the study of the quality and safety indicators of muffins of improved composition, manufactured using non-traditional raw materials. For the preparation of new types of muffins, part of the wheat flour was replaced with buckwheat, corn, oat, milk whey, skimmed milk powder and additives of vegetable origin. Margarine has been replaced by vegetable oils. It has been established that flour confectionery products have high organoleptic properties. From the physico-chemical parameters, the mass fraction of total sugar was determined, which ranged from 28.17 % to 33.07 %, the mass fraction of fat – 16.2–20.66 %, the mass fraction of moisture – 18.0–22.0, mass fraction of ash – 0.03–1.3 %, alkalinity – 0.03–1.8°, the content of toxic elements (copper, zinc, lead, cadmium, arsenic, mercury) and microbiological indicators were also determined. Based on the data obtained as a research result, the expediency of using non-traditional raw materials to expand the range of flour confectionery products, in particular muffins is substantiated.

Redox metabolism and cell wall modifications as global and local targets respectively, of cyanide induced dormancy release of walnut kernels

The HCN-induced seed dormancy release necessitates alterations in reactive oxygen species (ROS) metabolism and radicle cell wall loosening. Little is known about the interaction of ROS metabolism with cell wall hydrolytic enzymes during HCN-induced seed dormancy release. Thus dormant walnut (Juglans regia L.) kernels were exposed to HCN (4 h) and studied for redox metabolism and cell wall-modifying enzymes during 10 days of incubation (DI) i.e. before radicle emergence. HCN increased ROS especially in the embryonic axes (EAs) but decreased ROS-generating NADPH oxidase and ROS scavenging superoxide dismutase (SOD) and peroxidase (POX) with no effects on catalase (CAT), ascorbate peroxidase (APX) and cell wall-modifying enzymes activities in short term up to 2 DI. In long term roughly from 4 DI onwards, HCN-exposed EA displayed greater superoxide anions and enhanced activities of POX, APX, NADPH oxidase, cell wall peroxidase (CW-POX), β- 1, 4-D glucanase, mannanase, polygacturonase and xylanase. Meanwhile HCN increased greater expression of POX and mannanase isoforms as revealed by in-gel activity assay. Except for higher activities of CAT, POX and APX, cotyledonary activities of CW-POX, mannanase and polygacturonase and to some extent β- 1, 4-D glucanase remained unaffected by HCN. Thus short term ROS accumulation in HCN-treated EA is due to declined SOD and POX activities. In long term the enhanced activities of both NADPH oxidase: CW-POX couple and cell wall-modifying enzymes in EA bring about wall loosening in preparation for radicle emergence. Evidences for the simultaneous operation of both mechanisms are provided in walnut EAs during dormancy release.

Walnut (Juglans regia L.) kernel postharvest deterioration as affected by pellicle integrity, cultivar and oxygen concentration

Increased demand for convenient, healthy foods has promoted the commercialization of shelled, more perishable walnut kernels. In this work for two of the major commercial walnut cultivars (‘Chandler’ and ‘Howard’) we determined the influence that disruption of the integrity of the seed coat pellicle during shelling operations trigger postharvest deterioration. Commercially mature ‘Chandler’ and ‘Howard’ nuts were subjected to Gentle (GS, <4% pellicle area damaged per kernel) or Harsh Shelling (HS, 20–22% of pellicle area damaged) and stored in air at 25 or 35 °C (accelerated aging) for three or six weeks. During this period, which simulated current marketing and retail display, we evaluated kernel color changes (Dried Fruit Association of California ‘DFA’ scale, L* and Hue), ethanol-soluble phenolic antioxidants, oil-free fatty acids (FFA), and peroxide value (PV). The kernel color changed from ‘light’ to ‘amber’ during storage, as demonstrated by the decrease in extra light and light kernels and by the reduced lightness (L*) and Hue values. Pellicle browning (amber) incidence was common on HS kernels, which also lost more phenolic antioxidants during storage. Minimizing pellicle damage by GS operations reduced triglyceride hydrolysis and peroxidation. Kernel quality loss was largely dependent on cultivar; browning oxidation, and lipid hydrolysis and oxidation were faster in ‘Howard’ than in ‘Chandler’. Searching for a practical and direct postharvest technology, in absence of proper temperature control, to reduce the rate of kernel deterioration, we tested controlled atmospheres (CA) at different O2 concentrations (0.0, 3.0, 6.0 or 21.0 kPa) on both cultivars. Overall, commercially shelled ‘Howard’ and ‘Chandler’ (kernels) will benefit from retail packaging with oxygen concentrations equal to or lower than 3.0 kPa during warm retail display. This information will be useful for processors, distributors and produce handlers to protect snack-friendly, ready-to-eat walnuts.

True lipases beside phospholipases contribute to walnut kernel viability loss during controlled deterioration and natural aging

Little is known on the role of true lipases in aging of orthodox seeds. Walnut (Juglans regia L.) kernels rich in triacylglycerol stores lose viability after storage however, data on lipolytic activities and their correlation to kernel viability loss are lacking. Extracts from mature kernels contained acid (pH 5.0) and alkaline (pH 9.0) lipases, phospholipase A2 and fatty acyl-esterase activities. Kernels with moisture contents of 6, 15 and 20% were subsequently incubated for 3 and 6 days at 45 °C for controlled deterioration. Viability loss was greatest in kernels with 20% moisture content after 6 days. Lipase and phospholipase A2 activities increased but total lipid declined as kernels lost viability. Pre-treatements with diphenylmethyl-phosphanate or 1-butanol which specifically inhibited oil body mobilization and phospholipase D, respectively, inhibited viability loss of kernels after controlled deterioration. Diphenylmethyl-phosphanate inhibited in vitro lipase activity and kernels treated with this chemical also had reduced lipase activity. Declined kernel viability after one year storage was also associated with the increased lipase activities and the accumulation of free fatty acids in the neutral lipid fraction. Cyanide application increased germination and fatty acyl-esterase activity of non-aged kernels but resulted in viability loss of one-year stored kernels. Thus, the increased activities of lipases beside phospholipase might result in walnut kernel viability loss at higher temperature and moisture content while fatty acyl-esterase activity may be a marker of kernel ongoing metabolic activity.

The Productive Capacity and Quality of Several Walnut Cultivars (Juglans regia L.) Grown in North Oltenia, Romania

Romania has tradition in walnut culture and favorable climatic conditions. In order to establish the suitable cultivars for growing into the Northern Oltenia area several walnut cultivars of different origin were evaluated for productivity and fruits quality. Twelve Romanian cultivars and two foreign ones with terminal bearing and 10 cultivars with lateral bearing from France and U.S.A. were studied during 18 years of yielding with no irrigation. The group of lateral bearing cultivars proved to be more productive in the environmental conditions of the study area, the highest average yields were recorded for ‘Vina’ (3.64 t ha-1), ‘Hartley’ (3.59 t ha-1), ‘Ferjean’ (3.52 t ha-1), ‘Payne’ (3.45 t ha-1), ‘Pedro’ (3.39 t ha-1), etc. The most productive terminal bearing cultivars were: ‘Jupânești’ (2.88 t ha-1), ‘Valcor’ (2.77 t ha-1), ‘Franquette’ (2.71 t ha-1), ‘Valcris’ (2.62 t ha-1), etc. Although the lateral bearing cultivars emphasized good yields, their extensive culture into the areas with continental type of climatic conditions should be further analysed. The walnut kernel and oil content show that the cultivars are very similar regarding chemical composition when growing under same conditions in Northern Oltenia.&#x0D; &#x0D; *********&#x0D; In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 3, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue.&#x0D; *********

Effect of walnut kernel septum membranes hydroalcoholic extract on the shelf life of traditional butter

Incorporation of natural ingredients antioxidants in edible fats can profitably affect their oxidative stability during production and storage. The purposes of the current work were to assess the antioxidant and antimicrobial effect of walnut kernel septum membranes hydroalcohol extract (WHE) in traditional butter (TB). Antioxidant characterization of the extract was screened through methods of DPPH, reducing power and total phenolic assays. After preparation of traditional butter from yogurt, WHE was incorporated into TB at three different concentrations; 0.05%, 0.1% and 0.5% and compared with a control, BHT and tocopherol treated samples (200 mg of BHT and tocopherol/kg). Microbiological studies (Staphylococcus aureus, Coliforms, Psychrotrophic bacteria, yeasts and molds) were done during 90 days of storage time. Changes in Anisidine value (AV), acid value, peroxide value (PV) free fatty acids (FFA), Schaal and Totox value were monitored at 45-day intervals. Sensory evaluation was done using 10 semi-trained panelists based on the 5-point hedonic scale.It was found that the total phenolic content of WHE was 368.86 mg GAE/g. The BHT had higher antioxidant activity than WHE inhibiting 92.3% of the DPPH radical at 600 μg/mL. Peroxide value of TB treated with tocopherol, BHT and WHE 0.5% was 0.29 ± 0.07, 0.39 ± 0.07 and 0.52 ± 0.04 respectively. Furthermore, the WHE incorporated butter has shown low levels of free fatty acids, Schaal and Totox value when compared to control treatment. The WHE 0.5% incorporated sample had the most antimicrobial activity and it inhibited the growth of all the microorganisms (except Staphylococcus aureus) used in the study. Among the treated TB, the samples treated with the control and WHE 0.05% had the highest sensory attributes score. The study showed that WHE could be an excellent natural origin of antimicrobial and antioxidant agents which can be used in butter.

Characterisation of phenolics in fruit septum of Juglans regia Linn. by ultra performance liquid chromatography coupled with Orbitrap mass spectrometer

Walnut (Juglans regia L.) is an abundant source of polyphenols. Although phenolic species in the walnut kernel have been studied comprehensively, their compositional profile in the internal fruit septum, a traditional nutraceutical material in China, has been rarely explored. In the current study, the methanolic extract of the walnut septum was analysed by Ultra-performance liquid chromatography coupled with Orbitrap mass spectrometry. Totally seventy-five phenolics belonging to flavonoids, tannins and phenolic acids were identified based on mass spectra, references and literatures. Among them, quercetin-3-O-galactoside, quercetin-rhamnose-pentoside, quercetin-3-O-glucoside, quercetin-rhamnose-hexoside, kaempferol-rhamnoside, and two isomers of quercetin-rhamnoside were reported for the first time in walnut. The total polyphenol content was found to be 122.78 ± 2.55 mg GAE/g dry weight in septum. This study is the first to comprehensively investigate and identify phenolic compounds in the fruit septum of walnut and indicates that the septum to be a rich resource of polyphenols.

Protective effect of walnut on d-galactose-induced aging mouse model.

Objective (s)Accumulating evidence has suggested that oxidative stress and apoptosis are involved in the aging process. d‐galactose (gal) has been reported to cause symptoms of aging in mice, accompanied by liver and brain injuries. Our present work was to study the potential antioxidative and anti‐apoptotic effects of walnut and to explore how these effects act on mice in a d‐gal‐induced aging model.Materials and MethodsAging mice were induced by subcutaneous injection of d‐gal (200 mg kg−1 d−1 for 8 weeks). Walnut samples were simultaneously administered to the d‐gal‐induced aging mice once daily by intragastric gavage. Finally, body weight, organ index, cognitive function, levels of antioxidative enzymes, and liver function were monitored.ResultsThe kernel pellicles of walnut could not only improve the learning and memory ability, and the organ index, but also significantly decrease body weight and normalize the levels of activity of antioxidative enzymes in aging mice. Further, the walnut seed coat would protect damages of hippocampus and liver in aging mice.HighlightsIn the current study, we investigated the effects of walnut kernels and walnut seed coats (WSCs) on d‐galactose‐induced aging mice. WSC was firstly found to have beneficial effects on d‐gal‐treated mouse's brain with learning and memory impairment, which probably through the underlying mechanism reduces oxidative damage and limits neuroinflammation. In addition, WSC had a protective effect on liver damage in d‐galactose sensing mice.

Preservation effect of cinnamon and clove essential oil vapors on shelled walnut

Shelled walnut (Juglans regia) kernels are prone to rancidity during storage. In this study we examined the preservation effect of cinnamon and clove essential oil (EO) vapors compared to cold storage and vacuum packaging by measuring the hexanal content, indicating rancidity, in stored walnut kernels. Odor and taste of stored shelled walnut was investigated by sensory evaluation and by measuring residues of the main EO components in the kernels. During storage under EO vapors, cinnamaldehyde and eugenol were absorbed on the surface of walnuts in a time-dependent manner changing the odor and taste of the kernels. Clove (Syzygium aromaticum) EO prevented rancidity and EO treated kernels were rated as acceptable by the sensory panel while cinnamon EO treatment increased rancidity compared to the other treatments and the control samples.

Anticholinergic and Hypocholesterolemic Activity of Juglan regia Improves Cognitive Functions in Mice

Backgroud: Walnut appears as the Signature of the Head and the kernel looks alike as the brain. It is a traditional belief that Walnuts may be beneficial to the brain. Objective: In the light of this traditional belief, the present study was conducted to confirm the effects of Juglan regia (Walnut) on cognitive functions of mice. Method: Two doses (500, 1000 mg/kg) of Walnut kernel powder were administered along with diet for fourteen successive days to Swiss young and aged mice. 29 groups of 145 Swiss young mice and 13 groups of 65 aged mice were employed in the present study. Exteroceptive behavioral models used in the present study were elevated plus maze and passive avoidance apparatus. Results: Decreased TL and increased SDL values were indicative of a significant improvement in the memory of young and aged mice after Walnut powder administration. It also reversed the memory deficits induced by scopolamine and diazepam. In addition, the brain cholinesterase activity in young and aged mice was significantly inhibited by Walnut at the dose of 500 mg/kg. Walnut also showed a notable reduction in total cholesterol levels to the limit of 20% in young and 14% in aged mice at the dose of 500 mg/kg. Enhanced acetylcholine levels resulting from diminished AChE activity and hypocholesterolemia produced by Walnut appear to be the underlying mechanism for the improved memory of mice. Keywords: Walnut, Akhrot, Juglan regia, hypocholesterolemia, cognitive functions, brain cholinesterase.

Influence of Gum Arabic Enriched with GABA Coating on Oxidative Damage of Walnut Kernels.

SUMMARYBecause of the higher content of unsaturated fatty acids (UNSFA) and phenolics, walnut kernels are vulnerable to oxidative rancidity and browning due to unfavorable postharvest handling procedures. This study investigates the impact of gum arabic coating enriched with γ-aminobutyric acid (GABA) on oxidative rancidity and browning of kernels during storage at 20 °C. The results showed that the walnut kernels coated with gum arabic (5%) enriched with GABA (0.1 mM) exhibited lower oxidative rancidity and browning, manifested by lower peroxide value and malondialdehyde accumulation along with higher whiteness index. Moreover, kernels had higher UNSFA/SFA ratio as a response to lower lipoxygenase activity and H2O2 accumulation. The reduced oxidative browning in coated kernels was accompanied with lower polyphenol oxidase and higher phenylalanine ammonia-lyase activity leading to higher accumulation of phenolics and increased DPPH• scavenging capacity. Based on our findings, gum arabic coating (5%) enriched with GABA (0.1 mM) may have a commercial potential for maintaining nutritional quality of walnut kernels.

Effects of Cold-Press and Soxhlet Extraction Systems on Antioxidant Activity, Total Phenol Contents, Fatty Acids, and Tocopherol Contents of Walnut Kernel Oils.

In this study, physico-chemical properties, fatty acid composition, and tocopherol contents of several walnut kernel oils obtained through cold-press and Soxhlet extractions were investigated. The acidity, peroxide, and unsaponifiable matter of oil samples extracted in the Soxhlet system were found higher. Total phenol contents of the oils obtained in cold press and Soxhlet extraction systems were 121.9 mg GAE/100g (Kaman-2) and 154.6 mg GAE/ 100g (Büyükoba), and between 135.9 mg GAE/100g (Kaman-2) and 163.8 mg GAE/100g (Büyükoba), respectively (p < 0.05). In addition, antioxidant activity valuesof walnut oils obtained in cold press and Soxhlet extractions varied between 17.3% (Kaman-2) and 19.7% (Kaman-5), and between 18.4% (Kaman-2) and 23.8% (Büyükoba), respectively (p < 0.05). Linoleic acid contents of the oil samples extracted in cold-press varied between 55.19% (Kaman-5) and 56.71% (Kaman-2), while that extracted from Soxhlet extraction system varied between 54.47% (Kaman-2) and 55.93% (Büyükoba). ɣ-Tocopherol contents of walnut oils extracted in cold press and Soxhlet extraction ranged between 9.41 mg/100g (Büyükoba) and 10.83 mg/100g (Kaman-2), and 8.76 mg/100g (Kaman-5) and 9.33 mg/100g (Kaman-2), respectively, and were statistically significant (p < 0.05).

Ethyl gallate as a novel ERK1/2 inhibitor suppresses patient‐derived esophageal tumor growth

Ethyl gallate (EG) is a phenolic compound that is isolated from walnut kernels, euphorbia fischeriana, and galla rhois. It has been reported to exhibit antioxidant and anticancer activities. However, EG's effects on esophageal cancer have not yet been investigated. In the present study, we report that EG is a novel ERK1/2 inhibitor that suppresses esophageal cancer growth in vitro and in vivo. EG suppressed anchorage-dependent and -independent esophageal cancer cell growth. The results of in vitro kinase assays and cell-based assays indicated that EG directly binds to and inhibits ERK1 and ERK2 activities and their downstream signaling. Additionally, EG's inhibitory effect on cell growth is resistant to the re-activation of ERK1/2. EG increased G2/M phase cell cycle by reducing the expression of cyclin A2 and cyclin B1. The compound also stimulated cellular apoptosis through the activation of caspases 3 and 7 and inhibition of BCL2 expression. Notably, EG inhibited patient-derived esophageal tumor growth in an in vivo mouse model. These results indicate that EG is an ERK1/2 inhibitor that could be useful for treating esophageal cancer.

Walnut (Juglans regia L.) Kernel Extracts Protect Against Isoproterenol-Induced Myocardial Infarction in Rats.

Walnuts kernels (Juglans regia L.) have rich antioxidants content and have been used in both cosmetic and pharmaceutical industry. This study dealt with the protective role of walnut kernels extracts (WK) on isoproterenol (ISO)-induced myocardial infarction (MI) in rats. Rats were pretreated with WK extracts (300 mg/kg) daily for 35 days. Then, ISO (100 mg/kg) was injected subcutaneously into rats to induce MI. Cardiac diagnostic markers (LDH and CPK), cardiac troponin, heart lipid peroxidation (TBARS and hydroperoxide), antioxidant system (CAT, SOD, GPx, GST, GSH, and GSSG) and the levels of lipid profile were evaluated in rats, and the results revealed WK significantly prevented myocardial injury induced by ISO (p < 0.05). WK significantly alleviated the oxidative damage and dyslipidemia in ISO-induced MI rats (p < 0.05). The effect produced by WK was compared with α-tocopherol. The mechanisms for the protective effects of WK could be attributed to its antilipid peroxidative, antioxidant, and antilipidemic properties. In conclusion, we demonstrated that WK has a significant protective effect against ISO-induced MI.