High-oleic Peanuts Research Articles

Assessment of genetic diversity among Chinese high-oleic peanut genotypes using miniature inverted-repeat transposable element markers

As compared with normal-oleic peanuts, high-oleic peanuts proved to be heart-healthier and had a prolonged shelf life and extended seed longevity. However, there have been concerns about the genetic diversity of present-day high-oleic peanut cultivars, which relied heavily on high-oleic donors with F435 type FAD2 mutations. In the study, a total of 104 high-oleic peanut cultivars/lines/mutants from main breeding teams in China were used to assess their genetic diversity with AhMITE markers. Of all the 31 cultivars tested, those from CTW (Chuan Tang Wang) team had the highest genetic variability. Again, of all the 73 lines studied, those from the same team ranked first in genetic diversity. As compared with cultivars from CTW and C&Y (Xiao Yuan Chi and Shan Lin Yu) teams, greater genetic diversity was detected in new lines of both teams, indicating that recent breeding efforts had resulted in improved genetic diversity in high-oleic peanuts.

Study on Key Aroma Compounds and Its Precursors of Peanut Oil Prepared with Normal- and High-Oleic Peanuts.

High-oleic acid peanut oil has developed rapidly in China in recent years due to its high oxidative stability and nutritional properties. However, consumer feedback showed that the aroma of high-oleic peanut oil was not as good as the oil obtained from normal-oleic peanut variety. The aim of this study was to investigate the key volatile compounds and precursors of peanut oil prepared with normal- and high-oleic peanuts. The peanut raw materials and oil processing samples used in the present study were collected from a company in China. Sensory evaluation results indicated that normal-oleic peanut oil showed stronger characteristic flavor than high-oleic peanut oil. The compounds methylpyrazine, 2,5-dimethylpyrazine, 2-ethyl-5-methylpyrazine and benzaldehyde were considered as key volatiles which contribute to dark roast, roast peanutty and sweet aroma of peanut oil. The initial concentration of volatile precursors (arginine, tyrosine, lysine and glucose) in normal-oleic peanut was higher than in high-oleic peanut, which led to more characteristic volatiles forming during process and provided a stronger oil aroma of. The present research will provide data support for raw material screening and sensory quality improvement during high-oleic acid peanut oil industrial production.

The Effects of Feeding a Whole-in-Shell Peanut-Containing Diet on Layer Performance and the Quality and Chemistry of Eggs Produced

The abundance of peanut and poultry production within the state of North Carolina and the US Southeast, led us to conduct a layer feeding trial to determine the utilization of whole-in-shell high-oleic peanuts (WPN) and/or unblanched high-oleic peanuts (HOPN) as an alternative feed ingredient for poultry. To meet this objective, we randomly assigned 576 shaver hens to 4 dietary treatments (4 rep/trt). The dietary treatments consisted of a conventional control diet (C1), a diet containing 4% WPN, an 8% HOPN diet, and a control diet containing soy protein isolate (C2). Feed and water were provided for 6 weeks ad libitum. Pen body weights (BW) were recorded at week 0 and week 6 (wk6), and feed weights were recorded bi-weekly. Shell eggs were collected daily and enumerated. Bi-weekly 120 eggs/treatment were collected for quality assessment and egg weight (EW), while 16 eggs/treatment were collected for chemical analysis. There were no significant differences in BW or EW at week 6. Hens fed the C2 produced more total dozen eggs relative to C1 hens over the feeding trial (p < 0.05). Hens fed the C1 diet consumed less total feed relative to the other treatments with the best feed conversion ratio (p < 0.05). Most eggs produced from each treatment were USDA grade A, large eggs. There were no differences in egg quality, with the exception of yolk color, with significantly higher yolk color scores in eggs produced from the C1 and C2 treatments relative to the other treatments (p < 0.05). Eggs produced from the HOPN treatment had significantly reduced stearic and linoleic fatty acid levels relative to the other treatments (p < 0.05). Eggs produced from hens fed the WPN diet had significantly greater β-carotene content relative to eggs from the other treatment groups (p < 0.05). In summary, this study suggests that WPN and/or HOPN may be a suitable alternative layer feed ingredient and a dietary means to enrich the eggs produced while not adversely affecting hen performance.

Single kernel sorting of high and normal oleic acid peanuts using near infrared spectroscopy

Peanuts are known to contain nutrients that deliver cardiovascular and health benefits. One such compound is oleic acid, an omega-9 monounsaturated fatty acid, which occurs naturally in peanuts in the concentration range 40–55% m/m, while some varieties are known to contain oleic acid above 75% m/m. These high oleic peanuts have been shown to have cardiovascular health benefit by lowering lipid levels. Breeders are therefore interested in selecting for peanuts with high oleic acid content in a rapid, non-destructive manner. Near infrared spectra acquired on single peanut kernels was used to classify the kernels as either high oleic content or normal, low oleic content, by means of partial least squares discriminant analysis with an overall error rate in classification of 3.3%.

Comparative study of accelerated assays for determination of equivalent days in the shelf life of roasted high oleic peanuts: Chemical and volatile oxidation indicators in accelerated and room temperature conditions

Lipids present in peanuts are susceptible to oxidation, which affects food quality and safety, for this reason shelf-life studies are carried out. The objective was to determine the relation between accelerated oxidation conditions and room temperature storage for roasted peanuts. Lipid oxidation indicators and roasted flavour volatiles were measured. There was a negative correlation between roasted and oxidation volatiles. In this research, 2,5-dimethylpyrazine and 2-ethyl-3,6-dimethylpyrazine were good indicators of the storage conditions of roasted peanuts, and the peroxide value (PV) was the most important oxidation indicator. For the comparision of equivalent days, it was used the peroxide value which reached 7.90, 2.47 and 0.89 Meq.O2/kg after 21 days at 25, 45 and 60 °C, respectively. The accelerated storage condition of 60 °C is optimal for estimation of the shelf life at 25 °C wherein 1 day at 60 °C is equal to 8.79 days at 25 °C.

Effects of acute and chronic nuts consumption on energy metabolism: a systematic review of randomised clinical trials

Nuts are high-energy density foods and are associated with beneficial effects on health, including weight control. Effects on resting energy expenditure, respiratory quotient, and diet-induced thermogenesis are suggested mechanisms behind the effects of nuts consumption on weight control. Thus, we revised the randomised clinical trials that assessed acute and chronic nuts consumption effects on energy metabolism. Walnuts (22.1 g to 56 g) consumption appears to modulate energy metabolism markers differently depending on the dose and profile of the evaluated subject. In its turn, 56 g of high-oleic peanuts increased postprandial energy expenditure and thermic effect of food after three hours postprandial compared to consumption of conventional peanuts. Almonds, hazelnuts, peanuts, and a mix of nuts were the nuts studies in the chronic studies, which does not seem to influence energy metabolism markers. Further studies are needed to elucidate the effects of other types of nuts consumption on energy metabolism.

Combining ability for main quality traits in peanut (Arachis hypogaea L.)

High-oleic peanuts has been recognized by processing sectors, seed sellers and consumers for their longer shelf life, longer seed life and mutiple healthe benefits. High oleate is becoming a requisite ​for varietal releases in many peanut breeding programs at present. To select desirable parents for high-oleic peanut breeding, the study was conducted to evaluate the combining ability of 5 high-oleic donors from our research team, based on quality of individual single seeds. General combining ability was significant for oleic, linoleic, stearic and palmitic acid, oil and protein, while specific combining ability was significant for the traits except oil. Among them, oil content was found to be conditioned solely by additive gene actions, and for other quality traits, additive gene effects were more important than non-additive gene effects. High-oleic CTW and normal-oleic Xiaojingsheng were selected as the best general combiners for peanut oleic acid improvement. Narrow-sense heritability was high for quality traits other than protein, suggesting that there was high potential for genetic improvement in these traits.

Effect of variety and seed dressing on emergence of high-oleic peanut under low temperature and high soil humidity conditions

Low temperature coupled with high soil moisture during sowing to emergence generally results in poor peanut stand, thereby posing a non-negligible threat to peanut production in north and northeast China. Five high-oleic (HO) peanut cultivars and 4 seed dressing treatments capable of controlling several diseases and insect pests along with untreated checks were used to find the best combinations to cope with the dual stresses during sowing to emergence period. High broad-sense hereditability estimates of seedling emergence indicated great potential for genetic improvement of this trait. Analysis of variance in the split-plot experiment showed that the main effects of variety and seed dressing and their interaction on seedling emergence were significant. Seed dressing treatments increased seedling emergence percentage by 2.09–35.00 percent points. Four of the 5 HO peanut cultivars yielded satisfactory results. For Huayu 665, Huayu 668 and Huayu 965, Huweisanbao may be the best option; for Huayu 962, Weilidan was highly acceptable. These combinations will be evaluated further in multiple environments before large-scale extension.

The Effect of Feeding Hens a Peanut Skin-Containing Diet on Hen Performance, and Shell Egg Quality and Lipid Chemistry

Peanut skins are a considerable waste product with little current economic value or use. We aimed to determine the dietary effects of peanut skins on layer production performance and egg quality and chemistry of the eggs produced. Two hundred commercial hens were randomly assigned to four treatments (five replicates) and fed ad libitum for 8 weeks: conventional control diet, diet containing 24% high-oleic peanut (HOPN), diet containing 3% peanut skin (PN Skin), and a diet with 2.5% oleic acid (OA). Hens fed the HOPN diet had significantly reduced body weights relative to the control and PN Skin treatments, producing fewer total eggs over the 8-week experimental period. Eggs weights were similar between the control and PN Skin treatments at weeks 2 and 4, while eggs from the PN Skin treatment group were heavier than other treatments at weeks 6 and 8 of the experiment. Eggs produced from the HOPN treatment had reduced saturated fatty acid (FA) content in comparison to the other treatment groups, while similar between PN Skin and control eggs at week 8 of the experiment. This study suggests that PN skins may be a suitable alternative layer feed ingredient.

Feeding Laying Hens a Diet Containing High-Oleic Peanuts or Oleic Acid Enriches Yolk Color and Beta-Carotene While Reducing the Saturated Fatty Acid Content in Eggs

We investigated the dietary effects of high-oleic peanuts (HOPN) or oleic fatty acids (OA) on older production hen performance, egg mass and quality, and lipid composition. A total of 99 laying hens were divided between three treatments and fed ad libitum for 8 weeks: (1) Conventional diet; (2) HOPN diet; (3) OA diet. Body weight (BW) was measured at weeks 1 and 8, and feed, egg weights (EW), and egg quality parameters were collected. Data was analyzed by analysis of variance at p < 0.05 significance level. There were no treatment differences in 8 week BW, feed conversion ratio, or average weekly egg quality parameters. The 8 week average EW of eggs from the HOPN group had reduced EW relative to the other treatment groups (p = 0.0004). The 8-week average yolk color score (p < 0.0001) was greater in eggs from the HOPN group relative to the other treatments. Overall, the β-carotene (p < 0.006) and OA content (p < 0.0001) was greater in eggs from the HOPN group, with reduced saturated fats in eggs from the HOPN group relative to the other treatments. These results suggest that HOPN and/or OA may be a useful layer feed ingredient to enrich eggs, while significantly reducing egg size in older production hens.

Comparison of Field Emergence and Thermal Gradient Table Germination Rates of Seed from High Oleic and Low Oleic Near Isogenic Peanut Lines

ABSTRACT Oxidative stability is an important factor considered by those in the peanut manufacturing industry. Product stability has been shown to increase up to seven-fold when high-oleic peanuts are used. The percentage of US crop that is high-oleic continues to increase, but many producers are reluctant to grow high-oleic cultivars due to the uncertainty of the high-oleic effect on agronomic traits, such as seed germination, yield and grade. Experiments were designed and conducted to examine the effect of the high oleic trait on peanut seed germination in field plots and in the laboratory on a thermal gradient table. Genotypes used in these experiments included cultivars or breeding lines from each peanut market-type along with their near-isogenic, high oleic counterparts. Field emergence, or germination, was recorded in the field in 4 geographically different regions, as well as in the laboratory on a thermal gradient table. Thermal gradient table experimental results demonstrated a lag in germination in high oleic genotypes compared to their normal oleic counterparts in all market-types, but the effect was lowest in the runner-type pair. Results from these experiments increase the understanding of the agronomic properties of high-oleic peanut cultivars and could influence the modification of standard protocols used by state agencies to test high-oleic peanut germination for registered seed quality labeling. Furthermore, this study indicates that although producers may experience delayed germination from high oleic seed compared to low oleic counterparts, this germination lag is overcome by 21 days post-planting and does not negatively impact the agronomical performance of high oleic cultivars.

Measurements of High Oleic Purity in Peanut Lots Using Rapid, Single Kernel Near‐Infrared Reflectance Spectroscopy

AbstractHigh oleic peanuts have improved shelf life vs. conventional peanuts. Purity (percentage of high oleic peanuts within a lot) is critical to ingredient performance and final lot value. Contamination can result from unintentional mix‐ups at the breeder/seed level, improper production handling, or due to physiologically immature high oleic kernels. Therefore, industry groups have established unofficial sampling plans to monitor purity. Assuming equivalent measurement performance and simple random sampling, increasing the sample size decreases variance among replicated sample test results and increases the precision of estimated lot purity. A novel instrument (QSorter Explorer by QualySense AG) using near‐infrared reflectance spectroscopy was evaluated for high speed (20 kernels per second) high oleic purity measurements. The study objectives were to assess instrument performance in: (1) measuring oleic acid (%) in runner peanuts and (2) estimating the true high oleic purity of artificially mixed peanut lots. Three grades (Jumbo, Medium, and No 1) of US Runner mini‐lots each at seven different contamination levels (0, 5, 10, 20, 30, 50, and 100%) were prepared. Oleic acid (%) of individual kernels was measured by scanning replicated samples of 10, 50, 100, and 500 kernels using the QSorter Explorer. The variance associated with each sample size and lot contamination level on returned purity values is discussed in the context of binomial sampling. Overall, the demonstrated measurement performance and capacity of the QSorter Explorer to process much larger sample sizes suggest this instrument can better identify true high oleic peanut lot purity vs. other currently available technologies.

Construction of Saline-Alkali Tolerance Evaluation System and Isolation of Differentially Expressed Genes in High-Oleic Peanut (Arachis hypogaea L.)

As an important source of vegetable oil, peanut (Arachis hypogea L.) with both adequate tolerance and high-oleate could be a profitable choice in saline-alkali soil. In our study, two high-oleic peanut lines derived from the same cross and differing in saline-alkali response were initially identified from our previous field evaluation. In this study they were subjected to saline-alkali stress in pot culture, and their transcriptomes were analyzed. 16L1 possessed multiple characteristics related to saline-alkali stress tolerant, including well-developed green leaves, more pods, elevated proline, high levels of superoxide dismutase, catalase, peroxidase and strong photosynthetic capacity. According to the correlation of various indicators, we have established high-oleic peanut biological saline-alkali tolerance and physiological saline-alkali evaluation system. Ten differentially expressed genes (DEGs) responding to saline-alkali stress were characterized and confirmed by quantitative realtime reverse transcription PCR. A series of analyses of DEGs revealed the importance of secondary metabolites, osmotic adjustment substances, plant hormone signal transduction, and protein kinase in peanut saline-alkali tolerance. The output of this study will help to understand the saline-alkali tolerant mechanism and provide a reference for peanut saline-alkali tolerance.

Sodium azide induced high-oleic peanut (Arachis hypogaea L.) mutant of Virginia type

Less prone to oxidation than its conventional counterpart, high-oleic peanut (Arachis hypogaea L.) containing ≥ 72% oleate and < 8% linoleate is preferred by processors, seed sellers and consumers. Development of high-oleic peanut cultivars with suitable pod/seed size and shape may satisfy the need from food processors manufacturing whole kernel or halve products. In this study, a high-oleic Virginia type peanut mutant was identified through screening of a 15 mmol/L sodium azide mutagenized M3 population with near infrared spectroscopy. Sequencing of the mutated and wild type FAD2A/FAD2B genes detected 2 point mutations. The G448A mutation in FAD2A was the same as in previous reports, causing an amino acid change of D150N. G558A in FAD2B was a novel mutation, resulting in a stop codon and premature termination of protein synthesis. 16 promising lines with acceptable productivity and pod/seed characters have been tentatively bred, which will be evaluated further in yield tests with replications after seed increase.

Improving chemical and sensory quality of high-oleic peanut by application of foliar fertilizer

High-oleic peanut is favored by consumers because its a longer shelf life and benefits for cardiovascular health. Up to the high-oleic standard and with good taste is essential for peanut products in food processing. The aim of present study was to explore the effect of foliar fertilizers on chemical and eating quality of high-oleic peanuts. Three high-oleic peanut cultivars, namely Huayu 09C2, Huayu 9621, and Huayu 962, were used as materials. Huayu 09C2 and Huayu 9621 were planted in Fuxin, Liaoning, foliar sprayed with Fosforil at 2250 mL/ha, and Huayu 962 was sown in Jvnan, Shandong, foliar sprayed with Foliplus at 1500/3000 mL/ha. The chemical and sensory quality of peanut harvested from the treatment plots and controls was evaluated. Results showed that, Huayu 09C2 and Huayu 9621, foliar spraying with Fosforil in Fuxin, Huayu 962, foliar spraying with Foliplus in Jvnan, all still maintained high oleate content levels, and the Fosforil treatment was effective in raising the intensity of sweetness of roasted kernels. This study demonstrated the feasibility of improving chemical and sensory quality of high-oleic peanut through foliar fertilizer.

Hermetic Storage of Shelled Peanut Using the Purdue Improved Crop Storage Bags1

ABSTRACT Low oxygen or hermetic storage has been successfully used to store several commodities such as corn (Zea mays L.), cowpea (Vigna Savi), cocoa (Theobroma cocao), coffee (Coffea L.), and rice (Oryza sativa L.). However, previous research using hermetic storage for peanut or groundnut (Arachis hypogaea L.) had mixed results. Research was conducted to determine the effect on aflatoxin contamination, seed germination, and oil chemistry of shelled peanut hermetically stored in the Purdue Improved Crop Storage (PICS) bags for up to 12 months. A 2 × 4 factorial study included 1) normal and high oleic peanut, 2) two initial moisture contents by four storage treatments. The four storage treatments were 1) burlap bags as the control, 2) PICS bags, 3) PICS bags with air extracted by vacuum, and 4) PICS bags with sachets of chlorine dioxide (ClO2) dry fumigant added. There were three replications of each treatment combination. Peanut was stored in an area maintained at a temperature above 21C. The initial seed germination of the normal oleic and high oleic peanuts was 77 and 80%, respectively. Initial aflatoxin concentration in all peanut was less than 2 μg/kg. Bags were opened, sampled, and resealed at 60, 159, 249, and 301 d of storage. Approximately half of the 12 burlap bags suffered significant rodent damage, and all had significant infestation by Indian meal moth (Plodia interpunctella). Only 4 PICS bags had rodent damage with damage limited to the outer polypropylene bag. There were no live insects in the PICS bags. Seed germination decreased for all samples to an average of 6.3%. Peanut stored in the burlap bags had an average germination of 19.2% compared to 2.1% for peanut stored in PICS bags. The aflatoxin concentration in one of the burlap bags with normal oleic peanuts was 75 μg/kg, and one of the PICS bags with high oleic peanuts had an aflatoxin concentration of 12 μg/kg. The remaining samples had aflatoxin below the detectable limit of 2 μg/kg.

The effects of high-oleic peanuts as an alternate feed ingredient on performance, ileal digestibility, apparent metabolizable energy, and histology of the small intestine in laying hens.

We aimed to determine the effects of feeding a high-oleic peanut (HOPN) diet to egg-producing laying hens on egg quality, digestibility, and feed conversion. Three isonitrogenous and isocaloric dietary treatments were formulated with 1) Control diet (CON)-a corn-soybean meal conventional diet with 7.8 % added poultry fat, 2) HOPN diet-dietary inclusion of ~20% coarse-ground whole HOPN, and 3) oleic acid (CON-OA) diet-a control diet supplemented with 2.6% oleic fatty acid oil. Ninety-nine 57-wk-old brown Leghorn laying hens were randomly assigned to 33 animals per treatment. Animals were housed individually for 8 wk. Body and feed weights were recorded weekly and feed conversation ratio was calculated. Bi-weekly, shell eggs were analyzed for quality (yolk color, albumen height, and Haugh unit [HU]). Jejunum samples were collected at week 8 for histomorphometric analysis. Analysis of variance was performed on all variables using a general linear mixed model. Laying hens fed the CON-OA diet produced greater number of eggs relative to those fed the HOPN and control diets (P < 0.05). The roche yolk color value was higher (P < 0.001) in eggs from hens fed the HOPN diet. There were no differences in laying hen performance, eggshell color, eggshell strength, eggshell elasticity and egg albumen height, or egg HU, ileal fat digestibility, or villi surface among treatment groups. However, the apparent metabolizable energy (P < 0.01) and ileal protein digestibility (P = 0.02) were greater in laying hens fed the HOPN diet relative to the CON diet. This study suggests that whole unblanched high-oleic peanuts may be an acceptable alternative feed ingredient for laying hens.

Comparison of Dielectric Properties of Traditional and High-Oleic Runner-Type Peanuts at Microwave Frequencies

HighlightsPermittivity measurements were taken for traditional and high-oleic runner-type peanut pods and kernels at microwave frequencies.The dielectric constant, loss factor, loss tangent, and complex plane were compared between the two cultivars to observe any effect caused by the high-oleic trait.Despite differences in composition, minimal to no differences were observed in permittivity between the two cultivars.Abstract. Different cultivars of peanuts containing higher amounts of oleic acid have been developed to improve oxidative stability and overall peanut quality. Increasing oleic acid levels and decreasing linoleic acid levels in peanuts deter lipid oxidation, preventing the creation of off-flavors and increasing the shelf life. Since their conception, high-oleic peanuts have been tested from chemical and sensory perspectives to observe differences between them and traditional peanuts. Such tests have shown minimal differences, if any. However, tests to observe the effect of changing the levels of oleic and linoleic acid on permittivity, which is often used for nondestructive determination of the moisture content and bulk density of foods and agricultural products, have not been reported. Thus, a vector network analyzer (VNA) was used to take free-space transmission measurements of the complex permittivities of high-oleic and traditional runner-type peanut pods and kernels. Measurements were taken at 23°C between 5 and 9 GHz. Measurements yielded the dielectric constant and loss factor, which are often correlated to moisture content. Analysis was performed to compare the changes in the dielectric constant, loss factor, and loss tangent with moisture content for high-oleic and traditional peanuts. Linear trends were observed for each parameter with increasing moisture content for both cultivars. Results from the complex plane showed coefficient of determination (r2) values greater than 0.9 for pods and kernels. Therefore, at microwave frequencies, changing the levels of oleic and linoleic acid within the peanuts was observed to have minimal to no effect on their permittivity. Thus, moisture calibrations based on correlations between dielectric properties and moisture content for traditional runner-type peanuts can be applied to high-oleic cultivars. Keywords: Dielectric properties, Free-space transmission measurements, Microwave measurements, Oleic acid, Peanut kernels, Peanut pods.

Peanut Coffee: Enhancement of Nutritional, Physicochemical, and Sensory Characteristics in Coffee Brewed with Conventional and High-Oleic Peanut Extracts.

This study investigated nutritional, physicochemical, and sensory characteristics of coffee brewed with conventional and high-oleic peanut extracts. Compared to normal coffee, peanut coffee exhibited more diverse amino acids compositions. In constituent amino acids composition, peanut coffee exhibited increased proportions of glutamic and aspartic acids but decreased phenylalanine. Peanut coffee had higher thiamin, niacin, and sugar contents, improved antioxidant capacity, and lower caffeine contents. In electronic tongue analysis, peanut coffee showed an increased intensity of sweetness and umami taste but decreased bitterness, corresponding to the result of amino acids compositions and caffeine and sugar contents. In volatile compounds analysis using gas chromatography-mass spectrometry (GC/MS) with the sniffing test, peanut coffee had high concentrations of 2-ethyl-3,6-dimethylpyrazine, 2,2′-methylenebis-furan, and furfuryl propionate, which were perceived as peanut and roasted odors in the sniffing test. This study will provide informative data in extending the application of peanut to coffee and developing novel coffee, with added peanut, that is nutritionally beneficial.

Effect of High-Oleic Peanut Intake on Aging and Its Hippocampal Markers in Senescence-Accelerated Mice (SAMP8).

In many previous studies, the preventive effects of peanut against aging and cognitive impairment have often been unclear, so to clarify the effects we first investigated effective markers for evaluating its effects in the hippocampus of senescence-accelerated mouse prone/8 (SAMP8) mice, mainly using proteomics. The effects of dietary high-oleic peanuts on the hair appearance of SAMP8, the expression of effective markers in the hippocampus, and the TBARS and amino acid contents of the hippocampus were examined. Hippocampus solute carrier family 1 (glial high-affinity glutamate transporter), calcium/calmodulin-dependent protein kinase type II, and sodium- and chloride-dependent GABA transporter, which all are considered to be closely related to glutamic acid concentration were decreased by feeding of the samples, and the GABA/glutamic acid ratio in the hippocampus was increased by feeding with the samples. The formation of glial fibrillary acidic protein and synapsin-2, which showed higher levels in the SAMP8 than in SAMR1, and the protein expression of tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein and dihydropteridine reductase, which are considered to be related to the formation of adrenergic neuron transmitters, were reduced by the feeding of peanuts and their germ-rich fraction. Ferulic acid, as an ester and minor component in peanuts, could be partly connected to the effect of peanuts. These results indicate that high-oleic peanuts and their germ-rich fraction can protect against aging and cognitive impairment by regulating protein expression, which could be measured by the proteomics of the above hippocampus proteins of SAMP8 and the hippocampal GABA/glutamic acid ratio.