一种高利用价值油料作物-亚麻荠的研究进展

本文在对亚麻荠的栽培和育种现状进行阐述的基础上,重点概括了其种子中两种主要化学成分油脂和蛋白,具体包括油脂含量和脂肪酸组成、脂质活性成分及降血脂作用、油脂在生物能源上的应用,蛋白含量和氨基酸组成、蛋白饼粕加工利用等方面的研究现状。分析了约束亚麻荠发展的因素,并提出了相应的建议。     

Antioxidant properties and involved compounds of daylily flowers in relation to maturity

The antioxidant properties of methanol extracts from daylily flowers during maturation were determined with antioxidant assays, including antioxidant activity, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, superoxide anion radical scavenging and reducing power. Antioxidant compounds, such as phenolic compounds, ascorbic acid and β-carotene were also analysed. Significant variation in antioxidant properties and involved compounds was observed between different maturity stages of daylily flowers. The highest antioxidant activity was observed at stage III (flower opening) accompanying the highest content of ascorbic acid and phenolic compounds, while no significant difference of β-carotene contents was observed among the four maturity stages. Four individual phenolics, such as (+)-catechin, chlorogenic acid, rutin and quercetin were identified and quantified by HPLC. (+)-Catechin was the main phenolic compound identified in daylily flowers, accounting for about 74.11% of total phenolics. Overall, daylily flowers at opening stage possess the highest functional benefit and thus would be the appropriate harvesting stage in view of the nutritional consideration.     

Changes occurring in phenolic content,tocopherol composition and oxidative stability of Camelina sativa oil during storage

Changes occurring during storage in the content of polar phenolic compounds, the composition of tocopherols (T), the presence of primary and secondary oxidative products and titratable acidity in oil obtained from the seeds of Camelina sativa were studied. In fresh oil the content of polar phenolic compounds amounted to 128 mg/kg (expressed as chlorogenic acid), the content of α-T was (41 ± 8) mg/kg, of γ-T (710 ± 19) mg/kg and of δ-T (12 ± 3) mg/kg. β-T and tocotrienols were not detected. In oil stored at 50 °C the concentration of total tocopherols decreased to a value of (440 ± 13) mg/kg in 15 days. In that time the content of polar phenolic compounds in the oil stored at 50 °C was reduced to 72% of its initial value. The content of polar phenolic compounds in oil stored at 65 °C for 15 days was reduced to 21% of its initial value. The content of polar phenolic compounds in the C. sativa oil investigated decreased linearly with peroxide value and with p-anisidine value. The antioxidative activity of polar phenolic compounds extracted from camelina oil was also elucidated. Analysis revealed that the phenolic extract obtained from camelina oil added to a model lipid system for a certain time significantly retarded the process of autooxidation.     

Assessment of the antioxidant potential and fatty acid composition of four Centaurea L. taxa from Turkey

This paper focused on the assessment of antioxidant property and fatty acid composition of four Centaurea species. The antioxidant activity of its methanol extract was evaluated by several in vitro experiments including phosphomolybedum assay, DPPH assay, β-carotene/linoleic acid, ferric and cupric reducing power. Total phenolic and flavonoid contents were also evaluated. The methanol extract of Centaurea pulcherrima var. pulcherrima showed the superior free radical scavenging activity, linoleic acid inhibition capacity, reducing power and also had the highest total phenolic content. A significant relationship between antioxidant capacity and total phenolic components was found. The oils of Centaurea taxa were also analysed for fatty acid concentration by gas chromatography. The principal fatty acids in the species were palmitic acid (23.38–30.49%) and linoleic acid (20.19–29.93%). These findings suggest that the Centaurea species could be used as a potential source of new natural antioxidants and unsaturated fatty acids in food industry, cosmetics and pharmaceutical preparations.     

An investigation into green coffee press cake as a renewable source of bioactive compounds

The residual biomass of coffee, obtained after the oil extraction from coffee beans, called coffee beans residual press cake, has been attracted interest as a source of compounds with antioxidant capacity. This study investigated the effects of ethanolic and methanol-acetone extracts of green coffee beans (GCB) and its residual press cake (GCC) on the phenolic composition and antioxidant capacity. Antioxidant capacity was assayed through five different methods (total phenolic compounds, •DPPH, ABTS, FRAP and β-carotene bleaching assay), and the phenolic profile of the samples through High Performance Liquid Cromatography. GCB and GCC enclosed chlorogenic (55.16 and 64.96 mg g⁻¹, respectively) and caffeic (25.07 and 44.37 mg g⁻¹, respectively) acids as the major components, and the cake presented higher antioxidant capacity than the actual green bean. Antioxidant capacity was higher for GCC extracted with methanol and acetone. This study on the evaluation of the effects of the type of solvent on the bioactive compounds from GCB and GCC showed that this by-product can be a source of new value-added products, such as phenolic antioxidant adjuncts for food or pharmaceutic processing.     

Optimisation,characterisation and quantification of phenolic compounds in olive cake

The phenolic compounds in extracts from pressed olive cake were investigated. Free phenolic compounds were extracted from olive cake using methanol. To liberate bound phenolic compounds, the olive cake was subjected to basic and acidic hydrolysis followed by methanol extraction. The individual phenolic compounds and antioxidant activity of the extracts were determined. The highest total phenolic content and antioxidant activity were obtained using methanol extraction for 12 h at 70 °C. The RP-HPLC profiles for full-fat and defatted olive cake showed that protocatechuic acid, hydroxybenzoic acid, sinapic acid, p-coumaric acid, rutin and hesperidin were the predominant free phenolic compounds. Meanwhile, syringic acid, sinapic acid, caffeic acid and protocatechuic acid were the predominant bound phenolic acids. A positive correlation was observed between total phenolic content and antioxidant activity. The results indicated that most of the phenolic compounds in olive products were present in their free forms (75–90% of total phenolic content), while bound phenolic compounds were only a small proportion (10–25%) of total phenolic content.     

Non-toxic Salvia sclareoides Brot. extracts as a source of functional food ingredients: Phenolic profile,antioxidant activity and prion binding properties

Salvia sclareoides is an aromatic herb native to Portugal, of which phenolic content (Folin–Ciocalteau method), chemical profile (HPLC/DAD), antioxidant activity (DPPH, β-carotene/linoleic acid assays), acute toxicity (MTT method, adapted for non-adherent cells), genotoxicity (short-term chromosomal aberration assay) and prion binding properties were evaluated in the acetone, water, ethanol, methanol and n-butanol extracts. The latter presented the highest phenolic content and antioxidant activity (DPPH assay), and was the single one with the flavonoids (+)-catechin, kaempferol O-glucoside and quercetin. Vanillic acid was the major component of all extracts but gallic, gentisic, caffeic, syringic, coumaric and ferulic acids were also found in some extracts. Only the n-butanol extract had components binding to the cellular form of human prion protein detected by NMR which showed specificity for two regions of the folded domain and for the unstructured N-terminal region. Extracts were not cytotoxic nor genotoxic, reinforcing the potential of S. sclareoides for nutraceutical purposes.     

Antioxidant activity and contents of essential oil and phenolic compounds in flowers and seeds of Alpinia zerumbet (Pers.) B.L. Burtt. & R.M. Sm

Alpinia zerumbet leaves and rhizomes have been extensively studied for their chemical compositions and biological activities. However, less attention has been given to its flowers and seeds. In our study, essential oil, total phenolics and antioxidant capacities assayed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and β-carotene bleaching methods were evaluated in flowers and seeds of A. zerumbet. In addition, their phenolic composition was determined by GC–MS and HPLC. 1,8-Cineol, camphor, methyl cinnamate and borneol were the major constituents in flower oils, whereas the main components in seeds oil were α-cadinol, T-muurolol, α-terpineol, δ-cadinene and terpinene-4-ol. The results showed that the hexane extract of flowers contained a significantly higher quantity of dihydro-5,6-dehydrokawain (DDK) than that of seeds. Total phenolic contents of flower and seed extracts were measured as 56.7 and 13.7 mg gallic acid equivalent per gram extract, respectively. The ethyl acetate extract of flowers and seeds possessed a high antiradical activity and prevented the bleaching of β-carotene. The HPLC analysis indicated that p-hydroxybenzoic acid, ferulic acid and syringic acid were the predominant phenolics in the ethyl acetate extract of flowers, whilst p-hydroxybenzoic acid, syringic acid and vanillin were the major phenolics in seeds.     

Total phenols,ascorbic acid, β-carotene and lycopene in Portuguese wild edible mushrooms and their antioxidant activities

The antioxidant activities of three Portuguese wild edible mushroom species, Leucopaxillus giganteus, Sarcodon imbricatus, andAgaricus arvensis, were evaluated. Methanolic extracts were screened for their reducing power, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity, inhibition of erythrocytes hemolysis and antioxidant activity using the β-carotene linoleate model system. The amounts of ascorbic acid, β-carotene and lycopene found in the mushroom extracts were very low. Otherwise, the high contents of phenolic compounds might account for the good antioxidant properties found in all species. L. giganteus had the highest content of phenols and proved to be the most active, presenting lower EC₅₀ values in all the antioxidant activity assays.     

Identification of bioactive compounds and total phenol contents of cold pressed oils from safflower and camelina seeds

The compositions of fatty acids, tocopherols, polyphenols, sterols, and the total phenol contents of cold pressed oils obtained from five varieties of safflower seeds and ten varieties of camelina seeds cultivated in Turkey were determined. Total phenol contents of safflower oils were higher (272.20–525.30 mg GAE/kg) than camelina seed oils (25.90–63.70 mg GAE/kg). Apigenin, luteolin, tyrosol, syringic acid, 3-hydroxytyrosol, p-coumaric acid and sinapic acid were detected in seed oils. Camelina seed oils were rich in tocopherol (144.11–168.69 mg/100 g). γ-Tocopherol was the predominant tocopherol in camelina seed oils consisting of averagely 80% of total tocopherol, while α-tocopherol was the main compound of safflower seed oils, representing 97.85–98.53% of total tocopherols. β-Sitosterol was the major sterol in both type of seed oils. Its concentration ranged between 92.51–121.83 mg/100 g and 80.52–25.54 mg/100 g in safflower seed and camelina oils, respectively. Camelina seed oils contained 22.31–26.57% linolenic acid, 21.25–24.05% linoleic acid and 19.46–21.47% oleic acid, whereas safflower seed oils mainly consisted of linoleic (28.03–76.85%) and oleic (13.01–62.61%) acids.     

The impact of industrial processing on health-beneficial tomato microconstituents

The effect of industrial processing was investigated on the stability of tomato carotenoids, phenolic compounds and ascorbic acid. A deep insight in the processed products allowed the quantification of caffeic acid hexosides, which are far more important contributors than the well-known chlorogenic acid, dicaffeoylquinic acids and quercetin oligosaccharides (new feruloyl, sinapoyl and syringoyl derivatives of quercetin apiosylrhamnosylglucoside). (E)-β-Carotene and (E)-lycopene were also quantified along with different mono- and di-(Z)-isomers of lycopene which were tentatively assigned. Processing of fresh tomato into paste had an overall positive effect on the contents in phenolic compounds, no effect on lycopene and a slight and high detrimental effect on β-carotene and ascorbic acid, respectively. The balance between the increase in tomato matrix extractability and microconstituent catabolism was further observed in two contrasted transformations of paste into sauce. Overall, the nutritional quality of tomato-processed products, except for ascorbic acid, is mainly preserved through manufacture.     

Analysis of antioxidant activity and antioxidant constituents of Chinese toon

Antioxidant activity of the methanol and water extracts of Chinese toon (Toona sinensis) leaf was evaluated using DPPH radical scavenging and lipid peroxidation assays. Contents of four major types of antioxidants including β-carotene, ascorbate, α-tocopherol and phenolics were also quantified. Open column chromatography followed by semi-preparative HPLC were applied to separate phenolic antioxidants whose contents were subsequently determined by HPLC. The methanol extract demonstrated much higher antioxidant activity than the water extract. Contents of β-carotene, ascorbate, α-tocopherol and phenolics were 1.23 μmol g^?1, 34.2 μmol g^?1, 2.40 μmol g^?1 and 872 μmol gallic acid equivalents g^?1, respectively. Six phenols were isolated. Their structures were characterized as 5-O-galloylquinic acid, gallic acid, methyl gallate, β-1,2,6-tri-O-galloyl-d-glucose, quercetin 3-O-β-d-glucopyranoside and quercetin 3-O-(2′′-O-galloyl)-β-d-glucopyranoside, respectively. The results indicate that phenolic compounds are the dominant antioxidants in Chinese toon. The compounds β-1,2,6-tri-O-galloyl-d-glucose and quercetin 3-O-(2′′-O-galloyl)-β-d-glucopyranoside were reported for the first time in Chinese toon.     

Effects of Extraction Solvents and Provenances on Phenolic Contents and Antioxidant Activities of Cumin (Cuminum cyminum L.) Seeds

Polyphenol contents and 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) scavenging activity of cumin (Cuminum cyminum L.) seed extracts were compared depending on their geographical origin (Tunisia and India: TCS and ICS, respectively) and the extraction solvent polarity. The ??-carotene bleaching assay, the chelating ability and the reducing power of the most promising solvent extracts were also assessed. In addition, TCS and ICS extracts were acid-hydrolyzed and the phenolics identified by reversed-phase high-performance liquid chromatography (HPLC). Seed phenolic contents and antioxidant activity appeared to be accession and solvent dependent. Extraction with 80% acetone led to the highest polyphenol (18.60 and 16.50?mg gallic acid equivalents (GAE)/g dry weight (DW)), flavonoid (5.91 and 4.99?mg catechin equivalents (CE)/g DW) and tannin (83.23 and 80.23?mg CE/g DW) contents, respectively for TCS and ICS. DPPH scavenging activity, ??-carotene bleaching assay, chelating ability and reducing power were maximal in 80% acetone for both TCS and ICS. HPLC analysis revealed several phenolic compounds in C. cyminum seeds, with p-coumaric (4.83 and 2.33?mg/g DW), trans-2-dihydrocinnamic (1.09 and 1.20?mg/g DW) and rosmarinic (0.70 and 1.04?mg/g DW) acids as major phenolics in TCS and ICS, respectively. Thus, phenolic composition of cumin seeds is also origin dependent. Taken together, our findings indicate that cumin might constitute a rich and novel source of natural antioxidants as food additives in food industry and that acetone 80% would be the most appropriate solvent for seed extraction.     

Hazel (Corylus avellana L.) leaves as source of antimicrobial and antioxidative compounds

Aqueous extracts of leaves of different hazel (Corylus avellana L.) cultivars (Cv. M. Bollwiller, Fertille de Coutard and Daviana), were analysed by reversed-phase HPLC/DAD for the definition of their phenolic composition. Antioxidant potential was assessed by the reducing power assay, and the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and β-carotene linoleate model system. Their antimicrobial capacity was also tested against Gram positive (Bacillus cereus, Bacillus subtilis, Staphylococcus aureus) and Gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) and fungi (Candida albicans, Cryptococcus neoformans). Eight phenolic compounds were identified: 3-, 4- and 5-caffeoylquinic acids, caffeoyltartaric acid, p-coumaroyltartaric acid, myricetin-rhamnoside, quercetin 3-rhamnoside and kaempferol 3-rhamnoside. A p-coumaric acid, three myricetin and one quercetin derivatives were also detected. The hazel leaves extract presented high antioxidant activity in a concentration-dependent way, in general with similar behaviour of all cultivars. Gram positive bacteria revealed to be very sensitive to hazel leaf extract (MIC 0.1 mg/ml for B. cereus and S. aureus and 1 mg/ml for B. subtilis). However, Gram negative and the fungi displayed much lower sensitivity, being P. aeruginosa and C. albicans resistant at 100 mg/ml. Cv. M. Bollwiller exhibited the most potent antimicrobial activity.     

Essential Oil and Phenolic Compounds of Artemisia herba-alba (Asso.): Composition,Antioxidant, Antiacetylcholinesterase,and Antibacterial Activities

Total phenols, flavonoids, flavonols, and flavanols of the methanolic extract of the aerial part of Artemisia herba-alba were determined. The extract was analyzed by liquid chromatography with photodiode array coupled with electrospray ionisation mass spectrometry and allowed to identify of 10 phenolic compounds. Apigenin-6-C-glycosyl flavonoids and caffeoylquinic acids were identified. Chlorogenic acid and 1,4 dicaffeoylquinic acid being the major constituents. The essential oil obtained by hydrodistillation was analyzed by gas chromatography–mass spectrometry. Twenty-three compounds, representing 97.8% of the total oil, were identified. The most abundant components were β-thujone (41.9%), α-thujone (18.4%), and camphor (13.2%). Methanolic extract and essential oil exhibited a considerable antioxidant activity as evaluated by 2,2-diphenyl-pycrilhydrazil hydrate scavenging activity, reducing power, β-carotene bleaching test, and chelating ability. The methanolic extract was found to be more efficient, while the essential oil exhibited the highest acetylcholinesterase inhibitory activity. Analysis of the antibacterial activity showed that A. herba-alba methanolic extract and essential oil are efficient against gram positive and gram negative bacteria.     

Phenolic profile and antioxidant properties of a crude extract obtained from a brewery waste stream

The main aims of this study were to determine the phenolic profile of a crude extract obtained (at pilot scale) from a brewery waste stream and to evaluate the antioxidant activity of the extract. The total phenolic content was determined by the Folin–Ciocalteu assay, which revealed that 50% of the extract comprised phenolic compounds. The polyphenols, identified and quantified by RP-HPLC–DAD and HPLC-ESI–TOF-MS, were mainly flavonoids (catechin, epicatechin, gallocatechin, epigallocatechin, quercetin) and phenolic acids (ferulic acid, p-coumaric acid, caffeic acid, protocatechuic acid). The crude extract displayed a high DPPH radical scavenging activity (0.18 g/L), similar to that of BHA (0.248 g/L) and higher than that of BHT (2.54 g/L). All three tested products displayed a similar ability to decrease oxidative bleaching of β-carotene (antioxidant activity coefficient of 623.8 for the crude extract, 653.3 for BHA, 559.6 for BHT). This type of brewery waste stream may be a promising source of natural antioxidants to replace the synthetic antioxidants currently used in the food industry.     

Antioxidant, tyrosinase inhibitory, and acetylcholinesterase inhibitory activities of green tea (Camellia sinensis L.) seed and its pericarp

The present study evaluates antioxidant, tyrosinase inhibitory, and acetylcholinesterase (AChE) inhibitory activities of seed and its pericarp of tea plant (Camellia sinensis L.). Water and methanol extracts of tea seed and pericarp were prepared in a shaking incubator overnight at room temperature. The highest total phenolic contents, DPPH and ABTS radical scavenging activities, reducing power, β-carotene bleaching inhibition activity, highest tyrosinase inhibitory activity, and AChE inhibitiory activity were found in the methanol extracts of pericarp. Caffeine, gallic acid, several phenolic compounds, hydroxymethyl furfural, and fatty acid derived compounds were detected in the extract of tea seed and pericarp. The results indicate that seed and pericarp could be utilized as the potential resources for antioxidant ingredients in food industry. In addition, these compounds may protect Alzheimer’s disease as they had inhibitory activity of acetylcholine esterase.     

Antioxidant activity and phenolic content of phenolic rich fractions obtained from black cumin (Nigella sativa) seedcake

The antioxidant activities of crude methanolic extract (CME) and its fractions using ethyl acetate (EAF), hexane (HF) and water (WF) of black cumin seedcake were investigated. DPPH radical scavenging activity, β-carotene–linoleate bleaching, and inhibition of corn oil oxidation were used to evaluate the antioxidant capacity. The total phenolics were found to be 78.8, 27.8, 32.1 and 12.1 mg gallic acid equivalents (GAE)/g in EAF, CME, WF and HF, respectively. The CME and EAF exhibited the highest DPPH followed by WF and HF. The extract/fractions showed high effect on reducing the oxidation of β-carotene. The effect of extract/fractions on the oxidative stability of corn oil at 70 °C was tested in the dark and compared with butylated hydroxyanisole (BHA). The oil peroxide and anisidine values were generally lower with addition of PRFs in comparison to a control. The predominant phenolic compounds identified by HPLC–DAD in CME and WF of black cumin seedcake were hydroxybenzoic, syringic and p-cumaric acids.     

油茶籽油不同形态酚类化合物的抗氧化互作关系

本研究首先对油茶籽油中游离酚（free phenolics，FP）、酯化酚（esterified phenolics，EP）及不溶性结合酚（insoluble-bound phenolics，ISP）含量及主要物质组成进行分析，并通过测定铁离子还原能力、2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基清除能力、1,1-二苯基-2-三硝基苯肼自由基清除能力及β-胡萝卜素漂白能力对其中FP、EP及ISP的抗氧化活性及互作关系进行研究。结果表明，油茶籽油总酚含量为（137.97±5.14）mg/kg，其中ISP含量显著高于FP及EP（P＜0.05），占油茶籽油总酚的47.74%。另外，FP中以苯甲酸衍生物含量较高（主要为异香兰素及甲基香兰素），EP中主要为水杨酸，ISP中主要为3,4-二羟基扁桃酸。3 种形态酚类化合物在不同机制下的抗氧化能力不同，且呈现质量浓度依赖效应。FP＋ISP组合及EP＋ISP组合在抗氧化互作方面表现出一定的协同或相加作用，且后者复配组合的抗氧化活性更强；而FP＋EP组合和FP＋EP＋ISP组合则表现出拮抗或相加作用。