Phenolic Compounds, Antioxidant Activity and Fatty Acid Composition of Roasted Alyanak Apricot Kernel Fahad Y

Phenolic Compounds, Antioxidant Activity and Fatty Acid Composition of Roasted Alyanak Apricot Kernel Fahad Y. Al-Juhaimi1＊ , Kashif Ghafoor1, Mehmet Musa Özcan2, Nurhan Uslu2, Elfadıl E Babiker1, Isam A. Mohamed Ahmed1, and Omer N. Alsawmahi1 1 Department of Food Science & Nutrition, College of Food and Agricultural Sciences, King Saud University, Riyadh-SAUDI ARABIA 2 Department of Food Engineering, Faculty of Agriculture, University of Selçuk, 42031 Konya, TURKEY

Abstract: The oil recovery from Alyanak apricot kernel was 36.65% in control (unroasted) and increased to 43.77% in microwave-roasted kernels. The total phenolic contents in extracts from apricot kernel were between 0.06 (oven-roasted) and 0.20 mg GAE/100 g (microwave-roasted) while the antioxidant activity varied between 2.55 (oven-roasted) and 19.34% (microwave-roasted). Gallic acid, 3,4-dihydroxybenzoic acid, (+)-catechin and 1,2-dihydroxybenzene were detected as the key phenolic constituents in apricot kernels. Gallic acid contents varied between 0.53 (control) and 1.10 mg/100 g (microwave-roasted) and 3,4-dihydroxybenzoic acid contents were between 0.10 (control) and 0.35 mg/100 g (microwave-roasted). Among apricot oil fatty acids, palmitic acid contents ranged from 4.38 (oven-roasted) to 4.76% (microwave- roasted); oleic acid contents were between 65.73% (oven-roasted) and 66.15% (control) and linoleic acid contents varied between 26.55 (control) and 27.12% (oven-roasted).

Key words: apricot kernel, microwave roasting, oven roasting, total phenolics, antioxidant activity, fatty acids, phenolic compounds

1 Introduction assisted processing and thermos-analytical methods have Apricot（Prunus armeniaca L.; Rosaceae family）fruit is significant advantages over conventional methods for famous being delicious and nutritious. Apricot fruit starts edible oil extraction and characterization and they are to ripen at the end of July and it is fully ripened until mid- widely used to increase oil quality and to assess the stabili- August1）. Apricot kernel is a valuable by-product obtained ty of vegetable oils9－14）. Several studies have been con- after consumption and processing of fruit and it can be uti- ducted on chemical composition and phytochemical prop- lized for the recovery of edible oil. Phenolic compounds, erties of apricot fruit and kernels4, 6, 7）. However, contributing positively towards the antioxidant activity and comparative studies on roasting of apricot kernels using health benefiting properties, have been detected in apricot oven and microwave methods are still insufficient. The ob- kernels. These components also contribute to the oxidative jective of current research was to investigate the effects of stability of oil and being good sources of natural antioxi- oven- and microwave-roasting on total phenolics, antioxidants, phenolic compounds from apricot kernels, can be dant activity, individual phenolic constituents and fatty utilized for functional food development. Furthermore, acid composition of apricot kernels and their oil. apricot kernel oil also contains appreciable amount of poly- unsaturated fatty acids1－4）. Turkey is one of the biggest apricot producer in the world, which constitutes nearly 85％ of the global apricot production. The major portion of 2 Material and Methods harvested apricot fruit in Turkey is used in apricot nectar 2.1 Material production5）. Apricot kernel contains approximately Apricot fruits（Alyanak cv）were obtained from Konya, 30-48％ fat which consists of 56-73％ oleic, 20-32％ linoleic Turkey in 2019 and kernels were manually removed from and 300-600 mg/kg total tocopherol6, 7）. Individual phenolic the fruit. components may be damaged by the heat applied during roasting8）. Certain new techniques, including microwave-

＊Correspondence to: Fahad Y. Al-Juhaimi, Department of Food Science & Nutrition, College of Food and Agricultural Sciences, King Saud University, Riyadh-SAUDI ARABIA E-mail: [email protected] Accepted January 15, 2021 (received for review October 20, 2020) Journal of Oleo Science ISSN 1345-8957 print / ISSN 1347-3352 online http://www.jstage.jst.go.jp/browse/jos/ http://mc.manusriptcentral.com/jjocs

607 K. Ghafoor, F. Y. A.-Juhaimi, M. M. Özcan et al.

2.2 Methods nol. Antioxidant activity（％）was determined using follow- 2.2.1 Moisture content ing formula: The initial moisture content of the apricot kernel was measured at 105℃ in an oven until a constant weight was Antioxidant activity（％）＝ reached. ∆A control 517－∆A extract 517 ×100 2.2.2 Oven roasting ［ ∆A control 517 ］ Apricot kernels（100 g）were carefully roasted for 24 h at 70℃ using an oven. During roasting, they were stirred con- 2.2.7 Determination of phenolic compounds tinuously to ensure the homogenous roasting. The determination of individual phenolic constituents in 2.2.3 Microwave heating apricot kernel extracts was carried out using Shimadzu- Microwave roasting was carried out in an oven（Arçelik HPLC, connected to a PDA detector and an Inertsil ODS-3 ARMD 580, Turkey）with a power capacity of 720 W/25 min （5 µm; 4.6×250 mm）column. The mobile phase constitut- and working frequency of 2450 MHz. The microwave cavity ed 0.05％ Acetic acid in water（A）and acetonitrile（B） of oven had dimension of 34.5×34.0×22.5 cm. Approxi- mixture and its flow rate was set at 1 mL/min at 30℃. mately 50 g of apricot kernel sample, kept in 50 mL beaker, Samples（20 µL）were injected using autosampler and chro- and was placed at equal distances on a 28 cm diameter cir- matograms were recorded at 280 and 330 nm wavelengths cumference of rotary plate in the oven during each treat- in PDA detector. ment at 2450 MHz for 15 min. Once treated, samples were 2.2.8 Oil extraction cooled down at room temperature and stored in sealed Apricot kernels were ground to powder form in a small bottles at －25℃（ under nitrogen）before further chemical laboratory grinder followed by extraction of oil with petro- analyses. Samples were ground to a powder form prior to leum ether in Soxhlet Apparatus for 5 h. The solvent was analyses15）. then removed by evaporation using a rotary evaporator at 2.2.4 Extraction from apricot kernels 50℃19）. About 5 g powdered kernels sample was mixed with 2.2.9 Fatty acid composition methanol（15 mL）and then extraction was carried out in Evaluation of fatty acid composition of apricot kernel oil ultrasonic water-bath for 1 h followed by centrifugation at involved esterification of fatty acids using ISO-550920） 6000 rpm for 10 min. n-Hexane（10 mL）was added into fil- method and then fatty acid methyl esters were analyzed in tered supernatant and mixed in a vortex. The methanol a gas chromatography（Shimadzu GC-2010）system, which phases were collected from each step and evaporated at consisted of a flame-ionization detector（FID）and a capil- 50℃ to obtain a dried extract. The extract was then dis- lary column（Tecnocroma TR-CN100, 60 m×0.25 mm, film solved in 25 mL of methanol16）. thickness: 0.20 µm）. The temperature at injection block 2.2.5 Determination of total phenolic content and detector was set at 260℃, and nitrogen was used as Total phenolic contents in kernel extracts were evaluated carrier gas and its flow rate, total flow and split rates were as 750 nm wavelength using spectrophotometer（Shimadzu, set at 1.51 mL/min, 80 mL/min and 1/40, respectively19）. Japan）after treating the extracts with Folin-Ciocalteu reagent following Yoo et al.17）method. A 1 mL extract 2.3 Statistical analysis. sample was mixed with I mL Folin-Ciocalteu reagent and The results were obtained after triplicate measurements after 5 min, 10 mL 7.5％ Na2CO3 solution was mixed. The of replicated roasting treatments applied to apricot kernels final volume of the reaction mixture was made 25 mL using and the data was expressed as means±standard deviation deionized water; incubation was carried out for 2 h at room （MSTAT C）of independent roasting types 21）. temperature and absorbance values were recorded at 765 nm. Total phenolic contents were then reported as mg gallic acid equivalent（GAE）/100 g after comparing the sample results with those（calibration curve）of known con- 3 Results and Discussion centration of gallic acid（standard）solutions. 3.1 Moisture, oil, total phenolics and antioxidant activity 2.2.6 Antioxidant activity of apricot kernels The antioxidant activity of apricot kernel was investigat- The moisture, oil contents, total phenolic contents, anti- ed according to a DPPH（1,1-diphenyl-2-picrylhydrazyl） oxidant activity values of unroasted, and oven and micro- method as reported by Lee et al.18）. The apricot kernel wave roasted apricot kernels are presented in Table 1. The extract（1 mL）was dissolved in 2 mL of methanolic solution moisture contents of raw（control）and roasted kernels of DPPH by vigorous shaking and kept at room tempera- varied between 2.91％（ microwave-roasted）and 21.64％ ture for 30 min. Absorbance of the mixture was measured （control; unroasted）. The oil contents ranged from 36.65％ spectrophotometrically at 517 nm after reacting the known （control）and 43.77％（ microwave-roasted）in apricot quantities of sample extract with DPPH solution in metha- kernels. In addition, total phenol contents were detected

608 J. Oleo Sci. 70, (5) 607-613 (2021) Bioactive Properties of Apricot Kernel and Oils

Table 1 Some physicochemical properties of unroasted（control）, microwave-（720 W, 15 min） and oven-roasted（70℃, 24 h）Alyanak apricot kernels. Moisture content Total phenolic content Antioxidant Oil content Heat treatment (%) (mg GAE/100 g) activity (%) (%) Control 21.64±0.18*a 0.09±0.02b 5.44±0.01b 36.65±0.35c Microwave 2.91±0.19c** 0.20±0.15a 19.34±0.01a 43.77±0.03a Oven 3.23±0.24b 0.06±0.03c 2.55±0.02c 41.41±0.62b *means±standard deviation; **values in each column with different letters are significantly different (p < 0.05)

between 0.06（oven）and 0.20 mg GAE/100 g（microwave- measure the capacity of an antioxidant to reduce（demon- roasted）while antioxidant activity varied between 2.55％ strated by change in color）an oxidant and the degree of （oven）and 19.34％（ microwave-roasted）. It can be ob- color change is correlated with the sample’s antioxidant served that the moisture contents of apricot kernels was concentrations27, 28）. Besides differences with those report- reduced during roasting and the same time the recovery of ed in literature, total phenolics and antioxidant activities of oil was also partially enhanced. In addition, total phenolics apricot kernel samples showed differences depending on and antioxidant activity values of roasted apricot kernels roasting treatments applied in current study. increased during roasting. However, the increase in antioxidant activity values of roasted apricot kernels may also be 3.2 Individual phenolic compounds of apricot kernels a result of Maillard reaction and caramelization products The phenolic compounds of unroasted and oven（70℃ formed during roasting compared to control group（un- for 24 h）and microwave（720 W for 15 min）roasted apricot roasted apricot kernel）. Significant（p＜0.05）differences kernels are shown in Table 2. The amounts of individual were observed among chemical and bioactive properties of phenolic compounds were significantly（p＜0.05）affected roasted and unroasted apricot kernels. Chandrasekara and by roasting processes. The extracts from roasted and un- Shahidi22）determined that oil content was 41.30 to 42.58％ roasted apricot kernels were analyzed chromatographically in cashew nuts roasted at different temperatures. The oil and it was observed that the gallic acid contents varied yields of apricot kernels changed between 27.2％ and from 0.53 mg/100 g（control）to 1.10 mg/100 g（microwave- 61.4％（ w/w）dry weight basis depending on the geno- roasted）; 3,4-dihydroxybenzoic acid contents were type23）. Korekar et al.24）determined 92.2 to 162.1 mg between 0.10（control）and 0.35 mg/100 g（microwave- GAE/100 g total phenol in apricot kernels. Al-Juhaimi et roasted）;（＋） -catechin contents remained between 0.15 al.25）determined 54.41 mg GAE/100 g（Soğancıoğlu）to mg/100 g（microwave-roasted）and 0.32 mg/100 g（oven- 59.61 mg GAE/100 （g Hasanbey）in apricot kernels. In addi- roasted）; 1,2-dihydroxybenzene contents changed from tion, total phenolic contents in apricot kernel samples 0.08 mg/100 g（control）to 0.17 mg/100 g（oven-roasted）; roasted at 720 W were determined between 27.41 mg kaempferol contents were between 0.03 mg/100 g（oven- GAE/100 g（Çataloğlu）and 34.52 mg GAE/100 g roasted）and 0.24 mg/100 g（control）and isorhamnetin con- （Soğancıoğlu）in different varieties25）. Goma26）reported that tents varied from 0.04 mg/100 g（microwave-roasted）to total phenolic content and antioxidant activity value of 0.18 mg/100 g（control）. The unroasted apricot kernel sweet apricot kernel were identified as 3.290 mg/g and （control）was found to contain higher contents of syringic 59.53 mg/g, respectively. During the process of roasting, acid, caffeic acid, rutin-trihydrate, p-coumaric acid, trans- some chemical changes may occur in which sugars can ferulic acid, apigenin-7-glucoside, resveratrol and quercetin condense with free amino acids, peptides, or proteins than the roasted ones, which, may also be attributed to the leading to the formation of Brown Maillard reaction prod- sensitivity of these compounds to microwave and thermal ucts with potential antioxidant activity. Additionally, it has processing. In general, the phenolic compounds showed been stated that Folin-Ciocalteu reagent may not be differences in their contents depending on roasting types. precise for the determination of phenolic compounds as it Chandrasekara and Shahidi22）reported that the roasted may encounter certain analytical errors due to interaction cashew contained 0.251 mg/g of gallic acid, 0.867 mg/g of and reaction with other non-phenolic components of syringic acid, 0.112 mg/g of p-coumaric acid, 15.646 mg/g samples being analyzed. Hence, chromatographic proce- of（＋）-catechin, 8.368 mg/g of（－）-epicatechin and 6.544 dures（HPLC）may give better results during quantification mg/g of epigallocatechin. Al-Juhaimi et al.24）reported that of phenolic compounds23, 27）. Furthermore, this assay may the gallic acid contents of apricot kernels roasted at 540 W be more useful in assessing the total antioxidants reducing were higher（21.17 mg/100 g）than that of unroasted kernels capacity as being an electeon transfer-based assay it may （15.35 mg/100 g）. Certain variations in results of phenolic

609 J. Oleo Sci. 70, (5) 607-613 (2021) K. Ghafoor, F. Y. A.-Juhaimi, M. M. Özcan et al.

Table 2 Phenolic compounds（mg/100 g）in unroasted（control）, microwave- （720 W, 15 min）and oven-roasted（70℃, 24 h）Alyanak apricot kernels. Phenolics Control Microwave Oven Gallic acid 0.53±0.22*b 1.10±0.24a 0.86±0.61c 3,4-Dihydroxybenzoic acid 0.10±0.10c** 0.35±0.06a 0.14±0.03b (+)-Catechin 0.31±0.20b 0.15±0.01c 0.32±0.02a 1,2-Dihydroxybenzene 0.08±0.09c 0.11±0.05b 0.17±0.04a Syringic acid 0.13±0.10a 0.04±0.04b 0.04±0.02b Caffeic acid 0.09±0.10a 0.05±0.06b 0.04±0.01c Rutin trihydrate 0.32±0.08a 0.06±0.07c 0.07±0.03b p-Coumaric acid 0.07±0.03a 0.01±0.01b 0.01±0.00b trans-Ferulic Acid 0.10±0.07a 0.04±0.06b 0.03±0.05c Apigenin-7-glucoside 0.16±0.30a 0.06±0.05b 0.06±0.05b Resveratrol 0.03±0.02a 0.01±0.01b 0.01±0.00b Quercetin 0.13±0.07a 0.07±0.06c 0.08±0.01b trans-Cinnamic acid 0.01±0.00c 0.02±0.01b 0.03±a0.05 Naringenin 0.12±0.00b 0.03±0.00c 0.24±0.00a Kaempferol 0.24±0.00a 0.20±0.00b 0.03±0.00c Isorhamnetin 0.18±0.06b 0.04±0.03c 0.22±0.07a *means±standard deviation; **values in each row with different letters are significantly different (p < 0.05)

Table 3 Fatty acid composition（％）of unroasted（control）, microwave- （720 W, 15 min）and oven-roasted（70℃, 24 h）Alyanak apricot kernels.

Fatty acids Control Microwave Oven Palmitic 4.65±0.16*b 4.76±0.07a 4.38±0.05c Stearic 1.18±0.00b** 1.18±0.01b 1.23±0.00a Oleic 66.15±0.13a 65.95±0.02b 65.73±0.03c Linoleic 26.55±0.05c 26.62±0.01b 27.12±0.00a Arachidic 0.12±0.00 0.12±0.00 0.12±0.00 Linolenic 0.11±0.00a 0.10±0.00b 0.10±0.00b Behenic 0.03±0.00b 0.04±0.00a 0.04±0.00a Arachidonic 0.08±0.01 0.08±0.00 0.08±0.00 *means±standard deviation; **values in each row with different letters are significantly different (p < 0.05) compounds contents from those in literature can also be which also interfered with Folin-Ciocalteu reagent during due to ripening time, roasting method, roasting tempera- analysis. Therefore, this analytical method alone may not ture, microwave power and analytical conditions25）. By be correct to identify actual contents of phenolic com- adding the contents of 16 phenolic compounds as present- pounds27, 28）. ed in Table 2 it was observed that that unroasted kernels had a total of 2.6 mg/100 g of these compounds which was 3.3 Fatty acid composition of apricot kernel oil higher than microwave（2.34 mg/100 g）and oven（3.35 The fatty acid composition of oil samples from unroast- mg/100 g）roasted kernels. Hence, the higher total phenolic ed, oven-, and microwave-roasted apricot kernels are pre- contents and better antioxidant activity of microwave- sented in Table 3. Palmitic, oleic, and linoleic acids were roasted kernels may be due to certain other antioxidants, the key fatty acids in apricot kernel oils. Microwave（720 W

610 J. Oleo Sci. 70, (5) 607-613 (2021) Bioactive Properties of Apricot Kernel and Oils

for 15 min）and oven roasting（70℃ for 24 h）of apricot industrial food processing. Present study demonstrate kernels caused differences in fatty acids contents in oil. certain beneficial outcomes of applying microwave roasting Palmitic acid contents ranged from 4.38％, in oil from ov- to apricot kernels such as better recovery of oil and im- en-roasted kernels, to 4.76％, in oil from microwave-roast- proved biological properties due to liberation of more phe- ed kernels. Stearic acid contents varied between 1.18％ nolics and other bioactive compounds from kernel matrix. （control and microwave-roasted）and 1.23％（ oven-roasted; More studies can elaborate further the effects of microwave oleic acid contents changed between 65.73％（ oven-roast- roasting on phenolic constituents and other biologically ed）and 66.15％（ control）; linoleic acid contents ranged important molecules. from 26.55％（ control）to 27.12％（ oven-roasted）and linolenic acid contents were between 0.10％ and 0.11％. Roast- ing had no effect on arachidic and arachidonic acids of kernel oils. The palmitic and oleic acid contents in micro- Acknowledgements wave-roasted kernels were partially higher than oil from The authors would like to extend their sincere apprecia- oven-roasted kernels. In addition, the palmitic, oleic and tion to the Deanship of Scientific Research at King Saud linolenic acid contents in control oil（from unroasted University for its funding this Research group No（RG- kernels）were partially higher in oil from oven-roasted 1435-049）. kernels. However, arachidic, linolenic, behenic and arachidonic acid contents of roasted apricot kernel oils were found similar in both systems. Statistical significant（p＜ 0.05）differences were observed among palmitic, oleic and References linoleic acids of roasted and unroasted apricot kernel oils. 1） Yigit, D.; Yigit, N.; Mavi, A. Antioxidant and antimicro- Velickovska et al.29）reported that sweet apricot oil con- bial activities of bitter and sweet apricot（Prunus ar- tained 6.0％ palmitic, 3.4％ stearic, 57.8 ％ oleic and 29.00 meniaca L.）kernels. Braz. J. Med. Biol. Res. 42, 346- ％ linoleic acids. Oleic acid contents of unroasted and 352（2009）. roasted kernel oils ranged from 65.98％（ Soğancıoğlu）to 2） Bozan, B.; Temelli, F. Chemical composition and oxida- 71.86％（ Hasanbey）, and 63.48％（ Soğancıoğlu）to 70.36％ tive stability of flax, safflower and poppy seed and （Hasanbey）, respectively25）. Ogungbenle and Afolayan30） seed oils. Bioresour. Technol. 99, 6354-6359（2008）. determined 58.7％ oleic, 18.9％ linoleic and 12.1％ palmit- 3） Arranz, S.; Jimenez, J.P.; Calixto, F.S. Antioxidant ca- ic acids in cashew nut roasted in an oven. The oleic and pacity of walnut（Juglans regia L.）: Contribution of linoleic acids were the two key fatty acids of apricot kernel oil and defatted matter. Eur. Food Res. Technol. 227, oils; however, their content is affected meaningfully by the 425-431（2008）. variety and amounted to 38.5–67.2 and 26.4–54.8％, re- 4） Sharma, S.; Satpathy, G.; Gupta, R.K. Nutritional, phy- spectively31）. The present study shows that apricot kernels tochemical, antioxidant and antimicrobial activity of are a rich source of oil containing appreciable amounts of Prunus armenicus. J. Pharmacogn. Phytochem. 3 oleic and linoleic acids. Furthermore, bioactive properties, （3）, 23-28（2014）. fatty acid composition and phenolic compounds of un- 5） Tezcan, F.; Doğal Alan, S. Antioxidant activities, total roasted and roasted apricot kernel and oils may change de- phenolics and riboflavin profiles of Turkish commer- pending on analytical conditions, variety, geographical cial apricot nectars. Adıyaman University Journal origin and roasting methods32－36）. of Science 9, 36-47（2019）. 6） Alpaslan, M.; Hayta, M. Apricot kernel: Physical and chemical properties. J. Am. Oil Chem. Soc. 83, 469- 471（2006）. 4 Conclusions 7） Turan, S.; Topcu, A.; Karabulut, I.; Vural, H.; Hayalog- The recovery of oil from apricot kernels roasted in mi- lu, A.A. Fatty acid, triacylglycerol, phytosterol, and to- crowave was higher compared to that from unroasted copherol variations in kernel oil of Malatya apricots （control）kernels. Significant differences were observed from Turkey. J. Agric. Food Chem. 55, 10787-10794 among bioactive properties, fatty acid composition and （2007）. phenolic compounds in apricot kernels roasted using either 8） Yang, J.; Zhou, F.; Xiong, L.; Mao, S.; Hu, Y.; Lu, B. conventional（thermal）or microwave ovens. Microwave- Comparison of phenolic compounds, tocopherols, phy- （720 W, 15 min）and oven-roasting（70℃, 24 h）caused dif- tosterols and antioxidant potential in Zhejiang pecan ferences in fatty acid contents in apricot kernel oils which ［Carya cathayensis］at different stir-frying steps. varied from those in unroasted kernels in certain cases. Mi- LWT-Food Sci. Technol. 62, 541-548（2015）. crowave processing of foods is considered a new technique 9） Wesolowski, M.; Erecinska, J. Thermal analysis in qual- and it is gaining increased applications in household and ity assessment of rape seed oils. Thermochim. Acta

611 J. Oleo Sci. 70, (5) 607-613 (2021) K. Ghafoor, F. Y. A.-Juhaimi, M. M. Özcan et al.

323, 137-143（1998）. ganska-Marecik, R.; Grygier, A.; Rudzinska, M. Tocoph- 10） Silva, F.A.; Marsaioli, A. Jr.; Maximo, G.J.; Silva, erols, tocotrienols and carotenoids in kernel oils re- M.A.A.P.; Goncalves, L.A. Microwave assisted drying of covered from 15 apricot（Prunus armeniaca L.） macadamia nuts. J. Food Eng. 77, 550-558（2006）. genotypes. J. Am. Oil Chem. Soc. 94, 693-699（2017）. 11） Santos, J.C.O.; Santos, I.M.G.; Conceição, M.M.; Porto, 24） Korekar, G.; Stobdan, T.; Arora, R.; Yadav, A.; Singh, S.l.; Trindade, M.F.S.; Souza, A.G.; Prasad, S.; Fer- S.B. Antioxidant capacity and phenolics content of nandes Junior, V.J.; Araújo, A.S. Thermo analytical, ki- apricot（Prunus armeniaca L.）kernel as a function of netic and rheological parameters of commercial edible genotype. Plant Foods Hum. Nutr. 66, 376-383 vegetable oils. J. Thermal Anal. Calorimetry 75, （2011）. 419-428（2004）. 25） Al-Juhaimi, F.; Özcan, M.M.; Ghafoor, K.; Babiker, E.E. 12） Berteli, M.N.; Marsaioli, A. Jr. Evaluation of short cut The effect of microwave roasting on bioactive com- pasta air dehydration assisted by microwaves as compounds, antioxidant activity and fatty acid composi- pared to the conventional drying process. J. Food tion of apricot kernel and oils. Food Chem. 243, 414- Eng. 68, 175-183（2005）. 419（2017）. 13） Silva, F.A.; Marsaioli, A. Jr. Drying Brazil nuts using 26） Goma, E.Z. In vitro antioxidant, antimicrobial, and hot air assisted by microwaves compared to conven- antitumor activities of bitter almond and sweet apricot tionally dried samples. in Proceedings of the 9th inter- （Prunus armeniaca L.）kernels. Food Sci. Biotech- national conference on microwave and the high fre- nol. 22, 455-463（2013）. quency heating（Binner, J. ed.）. Loughborough, UK, 27） Górnaś, P.; Dwiecki, K.; Siger, A.; Tomaszewska-Gras, Sept. 1-5, pp. 341-344（2003）. J.; Michalak, M.; Polewski, K. Contribution of phenolic 14） Smith, A.L.; Barringer, S.A. Color and volatile analysis acids isolated from green and roasted boiled-type cof- of peanuts roasted using oven and microwave technol- fee brews to total coffee antioxidant capacity. Eur. ogies. J. Food Sci. 79, 1895-1906（2014）. Food Res. Technol. 242, 641-653（2016）. 15） Yoshida, H.; Nobuhisa, H.; Kajimoto, G. Microvawe en- 28） Huang, D.; Ou, B.; Prior, R.L. The chemistry behind ergy effects on quality of some seed oils. J. Food Sci. antioxidant capacity assays. J. Agric. Food Chem. 53, 55, 1412-1417（1990）. 1841-1856（2005）. 16） Jakopic, J.; Petkovsek, M.M.; Likozar, A.; Solar, A.; 29） Velickovska, S.K.; Mot, A.C.; Mitrev, S.; Gulaboski, R.; Stampar, F.; Veberic, R. HPLC-MS identification of Bruhl, L.; Mirhosseini, H.; Silaghi-Dumitrescu, R.; Mat- phenols in hazelnu（Corylus avellana L.）kernels. thaus, B. Bioactive compounds and“ in vitro” antioxi- Food Chem. 124, 1100-1106（2011）. dant activity of some traditional and non-traditional 17） Yoo, K.M.; Lee, K.W.; Park, J.B.; Lee, H.J.; Hwang, I.K. cold-pressed edible oils from Macedonia. J. Food Sci. Variation in major antioxidants and total antioxidant Technol. 55, 1614-1623（2018）. activity of Yuzu（Citrusjunos SiebexTanaka）during 30） Ogungbenle, H.N.; Afolayan, M.F. Physical and chemi- maturation and between cultivars. J. Agric. Food cal characterization of roasted Cashew nut（Anacardi- Chem. 52, 5907-5913（2004）. um occidentale）flour and oil. Int. J. Food Sci. Nutr. 18） Lee, S.K.; Mbwambo, Z.H.; Chung, H.S.; Luyengi, L.; 5, 1-7（2015）. Games, E.J.C.; Mehta, R.G. Evaluation of the antioxi- 31） Gornas, P.; Ramos, M.J.; Montano, M.C.; Rudzinska, M.; dant potential of natural products. Comb. Chem. High Radziejewska-Kubzdela, E.; Grygier, A. Fruit pits re- Throughput Screen. 1, 35-46（1998）. covered from 14 genotypes of apricot（Prunus arme- 19） AOAC. Official Methods of Analysis, 15th edn. Associa- niaca L.）as potential biodiesel feedstock. Eur. J. Lip- tion of Official Analytical Chemists, Washington, DC id Sci. Technol. 120, 1-10（2018）. （1990）. 32） Hojjati, M.; Lipan, L.; Carbonell-Barrachina, Á.A. Ef- 20） ISO-International Organization for Standardization, fect of roasting on physicochemical properties of wild Animal and vegetable fats and oils reperation of meth- almonds（Amygdalus scoparia）. J. Am. Oil Chem. yl esters of fatty acids, ISO. Geneve, Method ISO 5509, Soc. 93, 1211-1220（2016）. 1-6（1978）. 33） Vaidya, B.; Eun, J.B. Effect of roasting on oxidative 21） Püskülcü, H.; İkiz, F. Introduction to Statistic. Bilge- and tocopherol stability of walnut oil during storage in han Press. p333. Bornova. İzmir, Turkey（1989）（. in the dark. Eur. J. Lipid Sci. Technol. 115, 348-355 Turkish）. （2013）. 22） Chandrasekara, N.; Shahidi, F. Effect of roasting on 34） Liu, H-M.; Han, Y-F.; Wang, N-N.; Zheng, Y-Z.; Wang, phenolic content and antioxidant activities of whole X.-D. Formation and antioxidant activity of maillard cashew nuts, kernels, and testa. J. Agric. Food Chem. reaction products derived from different sugar-amino 59, 5006-5014（2011）. acid aqueous model systems of sesame roasting. J. 23） Górnas, P.; Radziejewska-Kubzdela, E.; Mišina, I.; Bie- Oleo Sci. 69, 391-401（2020）.

612 J. Oleo Sci. 70, (5) 607-613 (2021) Bioactive Properties of Apricot Kernel and Oils

35） Rudzińska, M.; Górnaś, P.; Raczyk, M.; Soliven, A. Ste- CC BY-SA 4.0（Attribution-ShareAlike 4.0 Interna- rols and squalene in apricot（Prunus armeniaca L.） tional）. This license allows users to share and kernel oils: the variety as a key factor. Nat. Prod. Res. adapt an article, even commercially, as long as ap- propriate credit is given and the distribution of de- 31, 84-88（2017）. rivative works is under the same license as the 36） Matthäus, B.; Özcan, M.M. Fatty acids and tocopherol original. That is, this license lets others copy, dis- contents of some Prunus spp. kernel oils. J. Food tribute, modify and reproduce the Article, provided Lipids 16, 187-199（2009）. the original source and Authors are credited under the same license as the original.

613 J. Oleo Sci. 70, (5) 607-613 (2021)