Composition and antioxidative activities of supercritical CO2-extracted oils from seeds and soft parts of northern berries

The present study investigated the composition and the antioxidative activities of oils from the seeds and the soft parts of a range of northern berries extracted by supercritical CO₂. The seed oils of the species of Rubus, Vaccinium, Empetrum, Fragaria and Hippophaë were rich in linoleic (18:2n-6, 34-55% of total fatty acids) and ??-linolenic (18:3n-3, 29-45% of total) acids with n-6:n-3 ratios of 1:1-1:2. The seed oils of the species Ribes contained, in addition to linoleic and ??-linolenic acids, ??-linolenic (18:3n-6) and stearidonic (18:3n-4) acids. In seed oils from European rowanberry (Sorbus aucuparia L.) and snowball berry (Viburnum opulus L.), linoleic and oleic (18:1n-9) acids together exceeded 90% of the total fatty acids. The sea buckthorn (SB) pulp oil had palmitoleic (16:1n-7), palmitic (16:0) and oleic acids as the major fatty acids. The SB pulp oil and snowball berry seed oil were rich in ??-tocopherol (120 and 110 mg/100 g oil, respectively), whereas raspberry seed oil contained a high level of ??-tocopherol (320 mg/100 g oil). Seed oils of cranberry (180 mg/100 g oil), Arctic cranberry (190 mg/100 g oil) and lingonberry (120 mg/100 g oil) are rich sources of ??-tocotrienol. The berry seed oils and the SB pulp oil showed varying peroxyl radical scavenging efficacies (300-2300 ??mol ??-tocopherol equivalent per 100 g oil) and inhibitory effects on perioxidation of microsomal lipids (250-1200 ??mol trolox equivalent per 100 g oil) in vitro. The peroxyl radical scavenging activity positively correlated with the total content of tocopherols and tocotrienols of the oils (r = 0.875, P = 0.001). The SB seed oil and pulp oil were active in scavenging superoxide anions produced by xanthine-xanthine oxidase system and inhibited Cu²⁺-induced LDL oxidation in vitro. The SB oils also protected purified DNA and rat liver homogenate from UV-induced DNA oxidation in vitro. The current research suggests potential of supercritical CO₂-extracted oils from northern berries as nutraceuticals and ingredients of functional foods.     

Influence of filtering of cold pressed berry seed oils on their antioxidant profile and quality characteristics

The quality, composition and colour of 11 oils from six different berries were evaluated before and after filtering of the cold-pressed oils. The filtering did not lead to significant compositional or quality differences, except a minor reduction in oxidative stability. Due to their high degree of unsaturation, the peroxide and p-anisidine values were high for all oils. However, the high level of tocopherols and tocotrienols appears to protect the oils during the oil stability test (significant correlation; r = 0.803; p = 0.003). Tocopherol contents between 138 mg/kg (kiwi seed oil, filtered) and 1639 mg/kg (blackberry seed oil, non-filtered) were found. Phenolic compounds, identified and quantified by HPLC, ranged from 90 mg/kg (blackberry seed oil, filtered) to 15,810 mg/kg (strawberry seed oil, filtered). No correlation was found between the quantified phenolic compounds and the oxidative stability of the oils, suggesting that in these oils the tocopherols were the main antioxidants protecting the lipids during storage.     

Fatty Acid Composition and Oxidative Stability of Cold-pressed Edible Seed Oils

ABSTRACT: This study was conducted to determine the fatty acid (FA) compositions and oxidative stabilities of cold-pressed cranberry, carrot, hemp, and caraway seed oils. The cold-pressed cranberry and hemp seed oils exhibited higher α-linolenic acid (18:3n-3) contents with levels of 22 and 19 g/100 g fatty acids, respectively. Cold-pressed carrot seed oil contained about 82% oleic acid and had the lowest total saturated fatty acids among all tested oils. Cold-pressed caraway seed oil had the greatest oxidative stability with an OSI value of 150 hours. In addition, cold-pressed carrot seed oil had the lightest color while hemp seed oil was the darkest among all the oils tested.     

Composition of Sugars,Organic Acids,and Total Phenolics in 25 Wild or Cultivated Berry Species

Abstract: Sugars, organic acids, and total phenolic content in fruit of 25 wild and cultivated berry species were identified and quantified with high‐performance liquid chromatograph. The composition of sugars, organic acids, and total phenolic compounds in various species of Vaccinium, Rubus, Ribes, and Fragaria genus was evaluated. Additonally, total phenolics of less known berry species of the Morus, Amelanchier, Sorbus, Sambucus, Rosa, Lycium, Actinidia, and Aronia genus were determined in wild growing as well as in cultivated fruits. Significant differences in the concentration of sugars and organic acids were detected among the berry species. Glucose and fructose were the most abundant sugars in berry fruits and the major organic acids were malic and citric acid. However, in kiwi fruit, sucrose represented as much as 71.9% of total sugars. Sorbitol has been detected and quantified in chokeberry, rowanberry, and eastern shadbush fruit. The highest content of total analyzed sugars was determined in rowanberry fruit, followed by dog rose, eastern shadbush, hardy kiwifruit, American cranberry, chokeberry, and jostaberry fruit. Rowanberry stands out as the fruit with the highest content of total analyzed organic acids, followed by jostaberry, lingonberry, red gooseberry, hardy kiwifruit, and black currant. The berries of white gooseberry, black currant, red currant, and white currant had the lowest sugar/organic acid ratio and were thus perceptively the sourest species analyzed. On the other hand, the species with highest sugar/organic acid ratio were goji berry, eastern shadbush, black mulberry, and wild grown blackberry. The highest amounts of total phenols were quantified in chokeberry fruit. Wild strawberry, raspberry, and blackberry had 2‐ to 5‐fold more total phenolics compared to cultivated plants. Practical Application: The fruit of analyzed berry species contained different levels of sugars, organic acids, and total phenolics. Moreover, it has been demonstrated that wild grown species generally contain more phenolics than cultivated ones. This information is interesting for nutritionists as well as berry growers and breeders who can promote the cultivation of species and new cultivars with higher phenolic content.     

Berry antioxidants: small fruits providing large benefits

Small berry fruits are consumed because of their attractive colour and special taste, and are considered one of the richest sources of natural antioxidants. Their consumption has been linked to the prevention of some chronic and degenerative diseases. The term ‘berry fruits’ encompasses the so‐called ‘soft fruits’, primarily strawberry, currants, gooseberry, blackberry, raspberry, blueberry and cranberry. The objective of this review is to highlight the nutraceutical value of berries and to summarize the factors affecting berry fruit antioxidants. Particular attention is given to postharvest and processing operation factors that may affect fruit phytochemical content. The structure–antioxidant relationships for phenolic compounds – the main group of antioxidants in this fruit group – are presented and major areas for future research are identified. © 2013 Society of Chemical Industry     

Changes of bioactive components in berry seed oils during supercritical CO2 extraction

The objective of the work was to elucidate the chemical composition of fractions of oil extracts obtained during the supercritical extraction on a semi‐industrial scale from strawberry (Fragaria x ananassa Duch.), chokeberry [Aronia melanocarpa (Michx.)], and raspberry (Rubus idaeus L.) seeds from industrial press cake. The oil extracts differed in terms of their content of bioactive components: carotenoids, tocopherols, chlorophylls, and fatty acids. Raspberry seed oil was the richest source of tocopherols (620.1–2166.7 mg kg^?1) and α‐linolenic acid (above 37%). Chokeberry seed oil had the highest content of linoleic acid (above 70%), and α‐tocopherol (166.0–1104.8 mg kg^?1). Strawberry oil was characterized by the highest content of chlorophylls and α‐linolenic acid (above 30%). It was showed that the oil fraction collected at the beginning of extraction is characterized by a high acid value, which requires purification steps to be used for food purposes.

Practical applications

Strawberry, raspberry, and chokeberry by‐products left over from the production of concentrated juice are a valuable source of oils rich in n‐3 and n‐6 polyunsaturated fatty acids, tocopherols, and carotenoids. The research showed that the fractionation of extracts in the course of supercritical extraction leads to oils with varying amounts of different bioactive compounds, and thus to products with potentially wide applications. Seeds oils have high potential utility as a source of unconventional oil for cosmetic and pharmaceutical sectors and biodiesel. Their targeted utilization may be exploited for economic, environmental and health benefits.     

HPLC–MS identification and quantification of flavonol glycosides in 28 wild and cultivated berry species

Berries and red fruits are rich dietary sources of polyphenols with reported health benefits. More than 50 different flavonols (glycosides of quercetin, myricetin, kaempferol, isorhamnetin, syringetin and laricitrin) have been detected and quantified with HPLC–MSⁿ in fruits of blueberry, bilberry, cranberry, lingonberry, eastern shadbush, Japanese wineberry, black mulberry, chokeberry, red, black and white currants, jostaberry, red and white gooseberry, hardy kiwifruit, goji berry, rowan, dog rose, Chinese and midland hawthorn, wild and cultivated species of blackberry, raspberry, strawberry and elderberry. The phenolic constituents and contents varied considerably among the analyzed berry species. Elderberry contained the highest amount of total flavonols (450–568 mg kg⁻¹ FW), followed by berry species, containing more than 200 mg kg⁻¹ FW of total: chokeberry (267 mg kg⁻¹), eastern shadbush (261 mg kg⁻¹), wild grown blackberry (260 mg kg⁻¹), rowanberry (232 mg kg⁻¹), american cranberry (213 mg kg⁻¹) and blackcurrants (204 mg kg⁻¹). Strawberry (10.5 mg kg⁻¹) and white currants (4.5 mg kg⁻¹) contained the lowest amount of total flavonols. Quercetins represent the highest percentage (46–100%) among flavonols in most analyzed berries. In wild strawberry and gooseberry the prevailing flavonols belong to the group of isorhamnetins (50–62%) and kaempferols, which represent the major part of flavonols in currants (49–66%). Myricetin glycosides could only be detected in chokeberry, rowanberry and species from the Grossulariaceae, and Adoxaceae family and Vaccinium genus. Wild strawberry and blackberry contained from 3- to 5-fold higher total flavonols than the cultivated one.     

Fatty acid composition,oxidative stability,antioxidant and antiproliferative properties of selected cold-pressed grape seed oils and flours

Cold-pressed chardonnay, muscadine, ruby red, and concord grape seed oils and their defatted flours were studied for their fatty acid composition, oxidative stability and antioxidant and antiproliferative activities. The phenolic profiles of the seed flours were also measured. The most abundant fatty acid in the oils was linoleic acid, ranging from 66.0 g/100 g of total fatty acids in ruby red seed oil to 75.3 g/100 g of total fatty acids in concord seed oil. The oils were also high in oleic acid and low in saturated fat. Ruby red grape seed oil recorded the highest oxidative stability index of 40 h under the accelerated conditions. Total phenolic content (TPC) was up to 100 times lower in the oils than in the flours. Lutein, zeaxanthin, cryptoxanthin, β-carotene, and α-tocopherol levels were also measured. DPPH radical-scavenging capacity ranged from 0.07 to 2.22 mmol trolox equivalents (TE)/g of oil and 11.8 to 15.0 mmol TE/g of flour. Oxidative stability of menhaden fish oil containing extracts of the seed flours was extended by up to 137%. HPLC analysis was conducted to determine the levels of free soluble, soluble conjugated and insoluble bound phenolics in the seed flours. The phenolic compounds analyzed included catechin, epicatechin, epicatechin gallate, quercetin, gallic acid, and procyanidins B1 and B2. Antiproliferative activity was tested against HT-29 colon cancer cells. All of the seed flours and muscadine seed oil registered significant (P < 0.05) inhibition of cancer cell growth. The results from this study demonstrate the potential of developing value-added uses for these seed oils and flours as dietary sources of natural antioxidants and antiproliferative agents for optimal health.     

Berry seed press residues and their valuable ingredients with special regard to black currant seed press residues

Berry seeds are distinguished by longevity though clear scientific appraisals cannot be made. Besides a hard seed coat other protecting substances are presumed in the seeds. Commonly the seeds are utilized as a source of oils. After pressing, there is a residue left that is still rich in bioactive ingredients. This paper gives an overview of the health-beneficial ingredients remaining in the residue of various berry seeds (bilberry, cranberry, rose hip, strawberry, elder, and black currant) with special focus on black currant. The fatty acid distribution and the content of fat, tocopherols and tocotrienols, phytosterols, carotenoids, vitamin C, fibre, protein, amino acids, dry matter, ashes, minerals, total phenols (gallic acid equivalent) and antioxidant capacity (TEAC) were determined. The investigation of berry seed press residues revealed that the total phenols and tocopherols were quantitatively the most important features of this material but there were significant differences between batches and cultures.     

Effects of pectolytic enzymes on selected phenolic compounds in strawberry and raspberry juices

To evaluate the effect of commercial pectolytic enzymes on the content of phenolic compounds (anthocyanins, flavonols and ellagic acids), strawberry and raspberry juices under enzymatic pectinase treatment were analyzed using High Performance Liquid Chromatography (HPLC) with Spectral Array Detection (SAD). Each fruit had a distinctive phenolic pattern which enabled identification and characterization. The stability of phenolic compounds during processing was monitored at 2, 4 and 6 h. The use of commercial pectinases modified the composition of phenolic compounds in relation of the fruits and the time considered. At 6 h, a loss of anthocyanins (−20%) present in raspberry juice was observed when Pectinex® BE 3-L, Rohapect® B1L, Rohament® MAX and Pectinex™ 3XL were used. This result confirmed the hypothesis of a β-glycosidase activity present into commercial pectinase. On the other hand, in strawberry treated samples the ellagic acids concentration always increased (up to 19 mg l⁻¹ with Pectinase™ LM, at 6 h) while flavonols content decreased (−35% with Pectinase™ LM, at 6 h). Rohapect® MB was the only enzyme able to considerably increase the content of total quercetin derivatives in raspberry (36 mg l⁻¹).     

FATTY ACID COMPOSITION OF THE SEED OIL OF ARUM ITALICUM MILLER

The genus Arum (Araceae) is represented by some 20 taxa in Turkey. Having tuberous roots, broadly hastate vigorous leaves, greenish-yellow spathes A. italicum grows in northern Turkey and flowers between April and May and its reddish berry type fruits ripen in July. Containing significant amount of calcium oxalate crystals, oxalic acid and oxalates in addition to volatile and/or easily destroyed irritating substances , Arum taxa are toxic. However, dried or fresh parts thereof are used for food and in folk medicine in Turkey. Tubers and ripe fruits are used in the treatment of rheumatism and hemorroids while the leaves are consumed as a food. The fatty acid composition of the seed oil of A. italicum oil was investigated by analyzing their methyl esters by GC and GC-mass spectrometry. The major fatty acids were 16:0, 16:1 n-7, 18:0, 18:1 n-9, 18:2 n-6 and 13-phenyltridecanoic acid in the seed oil. This is the first report on fatty acid composition and 13-phenyltridecanoic acid content of Arum italicum Miller seeds from Turkey.     

南瓜籽油中角鲨烯含量及特征指标比较

采用气相色谱、气相色谱-质谱和化学滴定法等手段,对我国不同产地的10个南瓜籽油的特征指标(碘值、皂化值、相对密度、折光指数、脂肪酸组成)和角鲨烯含量进行了分析,并和其他特种木本油脂中的角鲨烯含量进行比较。结果表明:南瓜籽油相对密度范围为0.9188~0.9215;折光指数为1.4560~1.4669;碘值为108.4~116.2 g/100 g;皂化值为188.9~192.4 mg/g;共检出14种脂肪酸成分,其中以亚油酸和油酸为主,亚油酸含量在44.7%~55.5%,油酸含量在23.8%~33.1%,10个南瓜籽油中不饱和脂肪酸含量均高于78.2%;南瓜籽油中角鲨烯含量较高(310~4446 mg/kg),与橄榄油相当,明显高于茶叶籽油、澳洲坚果油、核桃油、牛油果油等。综合考虑油脂色泽、角鲨烯含量和主成分分析结果,猜测角鲨烯含量差异较大的原因可能和油脂的制取工艺有关,部分南瓜籽油在深加工过程中损失了角鲨烯。南瓜籽油具有较高的营养价值,该研究对进一步挖掘南瓜籽开发应用前景,提高其综合利用价值提供了数据支撑。     

Antioxidant properties of cold-pressed black caraway,carrot, cranberry,and hemp seed oils

Cold-pressed black caraway, carrot, cranberry, and hemp seed oils were extracted with methanol and evaluated for radical-scavenging activities against ABTS⁺ and DPPH, chelating activity, oxygen radical absorbing capacity (ORAC), and total phenolic contents (TPC). All the oil extracts had significant antioxidant activities. The ORAC value ranged from 28 to 220 μmol TE/g oil for the cold-pressed hemp, carrot, and black caraway seed oils, whereas the ABTS⁺ – scavenging capacity ranged 8.9–30.8 μmol TE/g oil for the four cold-pressed edible seed oils. The greatest TPC, 3.53 mg gallic acid equivalent (GE) per gramme of oil, was detected in the cold-pressed black caraway seed oil extract, while the lowest TPC, 0.44 mg GE/g, was observed in the cold-pressed hemp seed oil extract. In addition, methanol extracts of the cold-pressed black caraway and cranberry seed oils were evaluated for their inhibitory capacities on human LDL oxidation by measuring the reduction of the thiobarbituric acid-reactive substance production (TBARS). Both oil extracts significantly suppressed the lipid peroxidation in human LDL, with TBARS reductions of 2.84 and 3.77 mg/g for cranberry and black caraway seed oil extracts, respectively. These results suggest that cold-pressed black caraway, cranberry, carrot and hemp seed oils may serve as dietary sources of natural antioxidants for health promotion and disease prevention, and the cold-pressed black caraway seed oil may be used as a natural antioxidative food additive for improving food quality and stability.     

Fatty Acid Content and Antioxidant Properties of Cold-pressed Black Raspberry Seed Oil and Meal

ABSTRACT: Cold-pressed black raspberry seed oil and meal were analyzed for their fatty acid contents and antioxidant properties. The oil contained about 35%α-linolenic acid (18:3n-3) and 55% to 58% linoleic acid. The meal exhibited strong free radical scavenging activities against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid diammonium salt (ABTS'+) radicals and had a total phenolic content (TPC) of 46 mg gallic acid equivalent/g meal. The ABTS+ scavenging capacity and TPC of the meal were 300 and 290 times greater than that of the oil. In addition, the oil stability iodine value, and color were examined. The results from this study suggest the possible food application of black raspberry seed and its fractions in improving human nutrition and potential value-adding opportunities in black raspberry production and processing.     

黑莓籽油脱色工艺及脂肪酸组成的GC/MS分析

对黑莓籽油的脱色工艺进行了研究,同时对黑莓籽油中脂肪酸的组成进行了GC/MS分析。结果表明:黑莓籽油的适宜脱色工艺条件为活性白土用量9%、脱色温度70℃、脱色时间15min;此条件下脱色,黑莓籽油色度降为R0.8、Y10.0;黑莓籽油主要含有硬脂酸、软脂酸、油酸、亚油酸和亚麻酸5种脂肪酸;其中以不饱和脂肪酸为主,相对含量约为85%;优化得到的脱色方法对黑莓籽油脂肪酸的组成和相对含量影响很小。     

Ascorbic acid contribution to ORAC values in berry extracts: An evaluation by the ORAC-pyrogallol red methodology

An oxygen radical absorbance capacity (ORAC) method based on pyrogallol red bleaching (ORAC-PGR) was used to evaluate the scavenging activity of berry extracts (blackberry, blueberry, and raspberry). Among berry extracts, only raspberry protected pyrogallol red through a clear induction time, related exclusively to ascorbic acid. The lag time allowed an estimation of the ascorbic acid concentration and its contribution to the total ORAC value, estimating that 66% of the ORAC-PGR value of raspberry is related to ascorbic acid. Also, from the induction time, an ascorbic acid concentration of 36 mg per 100 g of fresh weight was estimated for raspberry samples. The ORAC-PGR procedure could be considered as a fast and specific methodology for an estimation of ascorbic acid concentrations in complex samples.     

黑莓天然维生素E纯化技术研究

目的建立一种硅胶柱层析纯化黑莓种籽油中天然VE的方法。方法采用单因素实验的方法,以维生素E的含量为考察指标,对洗脱剂种类、洗脱剂配比、硅胶用量、洗脱剂用量进行优化。结果黑莓天然VE的最优纯化工艺参数为:硅胶与维生素E粗提物的质量比3?1;乙醇?正己烷(8?1,V/V)为洗脱剂,洗脱剂用量为粗提物的15倍。在此条件下,纯化物中维生素E的含量可以达到(51.5±0.530)%。结论采用硅胶柱层析方法可以有效纯化黑莓天然维生素E。     

CHEMICAL AND ANTIOXIDANT PROPERTIES OF CULTIVATED AND WILD FRAGARIA AND RUBUS BERRIES

ABSTRACT

Content of individual sugars, organic acids, total phenolics (TPH), some important phenolic compounds (kaempferol, myricetin, quercetin, and ellagic acid) and total antioxidant capacity (TAC) in the fruits of strawberry, raspberry and blackberry were studied. A comparison was made between cultivars and wild relatives of each species (Fragaria vesca L., Rubus idaeus L. and Rubus fruticosus L.). The main sugars found were fructose and glucose both in the fruits of wild species and the studied cultivars. Citric acid was determined to be the major organic acid in most of tested berries with the exception of blackberry cultivars, where malic acid was dominant. The content of individual phenolic compounds varied among the wild species, as well as among the studied cultivars. Ellagic acid content was higher in F. vesca, R. idaeus and R. fruticosus (122.5 µg/g FW, 12.71 µg/g FW and 61.7 µg/g FW, respectively) than that obtained in analyzed cultivars. Overall, TPH expressed higher values in the wild strawberry and blackberry species in comparison to the studied cultivars, and consequently, the highest levels of TAC were recorded in F. vesca (5.78 mg asc/g FW), followed by R. fruticosus (4.95 mg asc/g FW).

PRACTICAL APPLICATIONS

In recent years, both wild and cultivated berries have become very attractive for consumers because of potentially beneficial phytochemicals contained in these fruits. Fruit nutritional quality can be described by standard quality parameters (sugars and organic acids), and the analysis of antioxidant capacity influenced by specific related compounds. The importance of flavonoids and other phenolics have been suggested to play a preventive role in the development of cancer and heart disease. A significant positive correlation observed in this study between total phenolics and total antioxidant capacity indicate the need for the use of wild species in the breeding programs of small fruits, especially strawberry and blackberry, in order to increase their nutritive value and the health benefits.     

FATTY ACIDS AND TOCOPHEROL CONTENTS OF SOME PRUNUS SPP. KERNEL OILS

The oil content as well as the fatty acid and tocopherol composition of kernels from 15 Prunus spp. varieties from Turkey were determined. The oil yields from these kernels varied from 46.3 to 55.5%. The main fatty acids of Prunus spp. kernel oils were oleic acid (43.9–78.5%), linoleic acid (9.7–37%) and palmitic acid (4.9–7.3%). The total amount of vitamin-E-active compounds in the oils varied between 62.9 and 439.9 mg/kg. The predominant tocopherol in most kernel oils was γ-tocopherol. Only two varieties of P. amygdalus and one variety of P. persica showed α-tocopherol as the main vitamin-E-active compound. The composition of the oils was 9–164.5 mg/kg α-tocopherol, 21.5–41.6 mg/kg α-tocotrienol, 1.6–330.2 mg/kg γ-tocopherol and 0–39.1 mg/kg δ-tocopherol. From the results of the present study, it can be concluded that the kernels of the investigated species of Prunus fruits from Turkey may serve potential sources of valuable oil that might be used for edible and other industrial applications.

PRACTICAL APPLICATIONS

The search for new sources of vegetable oils is an ongoing challenge and the further utilization of by-products from the food processing industry is an interesting option in this field. Seed oils from Prunus species contain high amounts of recommended monounsaturated oleic acid moderate contents of linoleic acid and low amounts of saturated fatty acids that may result in more favorable oil than olive oil with regard to their fatty acid compositions. Additionally, the oils contain vitamin-E-active compounds. Both fatty acid composition and vitamin-E-active compounds may justify the further processing of seeds from Prunus species for the production of oil for food and pharmaceutical applications.