Use of the enantiomeric composition for the assessment of the authenticity of fruit beverages

Enantiomeric compositions of chiral terpenes in commercial fruit beverages were examined by solid phase microextraction-gas chromatography (SPME-GC). Optimization of the method was accomplished on the basis of some parameters involved in the extraction, such as heating temperature and extraction time, that provided the highest peak areas, 60 degrees C and 2 min being the optimal values. With the proposed method relative standard deviation (RSD) values from three replicates ranging from 2 to 12% were obtained. The enantiomeric distribution of some terpenes remained constant, whereas other terpenes (linalool, terpinen-4-ol, and alpha-terpineol) exhibited a considerable variation among samples. This can be indicative of the eventual addition of aromas to some fruit beverages.     

Characterization of the volatile constituents in the essential oil of Pistacia lentiscus L. from different origins and its antifungal and antioxidant activity

Essential oil (EO) from aerial parts (leaves, juvenile branches, and flowers when present) of Pistacia lentiscus L. growing wild in five localities of Sardinia (Italy) was extracted by steam-distillation (SD) and analyzed by gas chromatography (GC), FID, and GC-ion trap mass spectrometry (ITMS). Samples of P. lentiscus L. were harvested between April and October to study the seasonal chemical variability of the EO. A total of 45 compounds accounting for 97.5-98.4% of the total EO were identified, and the major compounds were alpha-pinene (14.8-22.6%), beta-myrcene (1-19.4%), p-cymene (1.6-16.2%), and terpinen-4-ol (14.2-28.3%). The yields of EO (v/dry w) ranged between 0.09 and 0.32%. Similar content of the major compounds was found in samples from different origins and seasonal variability was also observed. The EOs were tested for their antifungal activity against Aspergillus flavus, Rhizoctonia solani, Penicillium commune, Fusarium oxysporum. Two samples were weakly effective against Aspergillus flavus. Furthermore, terpinenol and alpha-terpineol, two of the major components of EO of Pistacia lentiscus L., totally inhibited the mycelian growth of A. flavus. Quite good antioxidant activity of the EO was also found.     

Characterization, antibiofilm, and mechanism of action of novel PEG-stabilized lipid nanoparticles loaded with terpinen-4-ol

Terpinen-4-ol, an active component of tea tree oil, exhibits broad-spectrum antimicrobial activity. However, the high volatilization of terpinen-4-ol and its nonwettability property have limited its application. Our objective was to synthesize novel nanocarriers to deliver and protect terpinen-4-ol. The polyethylene glycol (PEG)-stabilized lipid nanoparticles were prepared and characterized by scanning electron microscope, Zetasizer, and differential scanning calorimetry. These nanoparticles had an average diameter of 397 nm and a Ζ-potential of 10 mV after being modified by glycine. Results showed that homogeneous particle size, high drug loading, stability, and targeting were obtained by the nanoparticles. Liquid chromatography/mass spectrometry showed a sustained release trend from nanoparticles for terpinen-4-ol. Minimum inhibitory concentration and minimum biofilm eradication concentration were tested against Candida albicans ATCC 11231. Studies on isolated mitochondria showed the blockage of biofilm respiration and inhibition of enzyme activity. The effects can be ascribed to localization of terpinen-4-ol on the membrane of mitochondria.     

Composition and seasonal variation of the essential oils from two mandarin cultivars of southern Brazil

Cold-pressing and hydrodistilled peel oils of two Brazilian mandarin cultivars, commonly called Cai and Montenegrina (Citrus deliciosa Tenore), were obtained from fruits collected on mandarin trees submitted to the same pedoclimatic and cultural conditions. Their chemical composition and seasonal variation of the main volatile constituents were investigated by capillary GC and GC-MS, and the results were submitted to statistical analysis. To better characterize the oils, the enantiomeric distribution ratio of seven components (alpha-pinene, sabinene, beta-pinene, limonene, linalool, terpinen-4-ol, and alpha-terpineol) was determined by multidimensional gas chromatography (MDGC). The similarities found between both C. deliciosa cultivars are strong evidence for the hypothesis that Montenegrina originated from Cai as previously reported from agronomic studies.     

Volatile constituents and key odorants in leaves, buds, flowers, and fruits of Laurus nobilis L

The volatiles of fresh leaves, buds, flowers, and fruits from bay (Laurus nolilis L.) were isolated by solvent extraction and analyzed by capillary gas chromatography-mass spectrometry. Their odor quality was characterized by gas chomatography-olfactometry-mass spectrometry (HRGC-O-MS) and aroma extract dilution analysis (AEDA). In fresh bay leaves 1,8-cineole was the major component, together with alpha-terpinyl acetate, sabinene, alpha-pinene, beta-pinene, beta-elemene, alpha-terpineol, linalool, and eugenol. Besides 1,8-cineole and the pinenes, the main components in flowers were alpha-eudesmol, beta-elemene, and beta-caryophyllene, in fruits (E)-beta-ocimene and biclyclogermacrene, and in buds (E)-beta-ocimene and germacrene D. The aliphatic ocimenes and farnesenes were absent in leaves. By using HRGC-O-MS 21 odor compounds were identified in fresh leaves. Application of AEDA revealed (Z)-3-hexenal (fresh green), 1,8-cineole (eucalyptus), linalool (flowery), eugenol (clove), (E)-isoeugenol (flowery), and an unidentified compound (black pepper) with the highest flavor dilution factors. Differences between buds, flowers, fruits, and leaves with regard to the identified odor compounds are presented.     

Comparison of eucalyptus camaldulensis Dehn. oils from Mozambique as obtained by hydrodistillation and supercritical carbon dioxide extraction

Leaf oils of E. camaldulensis Dehn. from Mozambique obtained by hydrodistillation and by supercritical carbon dioxide extraction under different conditions were compared with regard to their major components. The oil obtained by hydrodistillation showed high concentrations of 1,8-cineole (43%), alpha-pinene (5.5%), beta-pinene (3.4%), p-cymene (5.2%), terpinen-4-ol (3.1%), and globulol (4.1%). The extracts obtained by supercritical carbon dioxide extraction have lower amounts of 1,8-cineole, alpha-pinene, beta-pinene, and terpinen-4-ol, but have higher amounts of allo-aromadendrene and globulol. At the same time, distilled oil of E. radiata was extracted from an inert matrix (Celite) and the extract showed a higher content of 1,8-cineole at 80 bar and 60 degrees C than the feed, suggesting that a multiple-stage supercritical carbon dioxide extraction of the E. camaldulensis studied can produce an oil close to the market requirements set by the European pharmacopoeias.     

Composition and antimicrobial activity of the essential oils of two Origanum species

The essential oils obtained from the aerial parts of Origanum scabrum and Origaum microphyllum, both endemic species in Greece, were analyzed by means of GC and GC-MS. Forty-eight constituents were identified, representing 98.59 and 98.66% of the oils, respectively. Carvacrol, terpinen-4-ol, linalool, sabinene, alpha-terpinene, and gamma-terpinene were found as the major components. Furthermore, both samples exhibited a very interesting antimicrobial profile after they were tested against six Gram-negative and -positive bacteria and three pathogenic fungi.     

Preferred age for assessment of qualitative and quantitative characteristics of the essential oil of tea tree (Melaleuca alternifolia) seedlings prior to plantation establishment

An analytical method for determining the quality and hence the chemical variety status of tea tree transplants is described. The key to the procedure was found to be the leaf age of the test material. Investigation at very early development stages was seen to give misleading results due to the sequential onset of different monoterpenoid biogenetic pathways. For example, in the first few leaves, the high concentration of terpinolene in the terpinen-4-ol variety suggests that the terpinolene variety is under investigation. However, 1,8-cineole percent concentrations in plantation tree leaf were approximately 1.6 times lower than those measured for seedlings prior to transplant. Consequently, the use of a plantation cineole indicator is proposed for estimating plantation cineole from seedling leaf analyses. Although recent investigations enable the chemotype status to be predicted with some certainty, it is now proposed that analysis of leaf set 10 at the age of 6 weeks (seedling age approximately 17 weeks) provides an unambiguous analysis and correlates seedling quality with mature plantation quality. In addition, the oil yield of mature tea tree leaf was found, by steam distillation, to be approximately 5 times higher than that of seedling leaf.     

Volatile composition in raspberry cultivars grown in the Pacific Northwest determined by stir bar sorptive extraction-gas chromatography-mass spectrometry

Twenty-nine volatile compounds in 'Chilliwack', 'Tulameen', 'Willamette', 'Yellow Meeker', and 'Meeker' raspberries were quantified using stir bar sorptive extraction (SBSE) paired with gas chromatography-mass spectrometry (GC-MS). Good correlation coefficients were obtained with most aroma-active compounds in raspberry, with quantification limits of 1 microg/kg. However, poor recoveries were observed for raspberry ketone and zingerone. Quantitative data showed that volatile concentrations varied for different cultivars. Large variations for alpha-ionone, beta-ionone, geraniol, linalool, and ( Z)-3-hexenol were observed in different raspberry cultivars. In addition, the volatile compositions in 'Meeker' raspberry grown at different locations also varied. The chiral isomeric ratios of raspberry ketone, alpha-ionone, alpha-pinene, linalool, terpinen-4-ol, delta-octalactone, delta-decalactone, and 6-methyl-5-hepten-2-ol were studied using a CyclosilB column. alpha-Ionone, alpha-pinene, delta-octalactone, and delta-decalactone had strong chiral isomeric preference, with more than 96% for one isomeric form. Much weaker chiral isomeric preference was observed for terpinen-4-ol, while linalool was almost a racemic mixture. Both growing locations and cultivars affect the isomeric ratio of linalool with a range of 37-51% for ( R)-linalool.     

甜菜生育期叶面营养调节对其产量和含糖率作用的研究

为提高甜菜的含糖量,设置了甜菜不同生育阶段叶面喷施营养液提高其含糖量的效果试验。两年田间试验结果表明:叶丛快速生长期,以喷施KH2PO4+ZnSO4或KH2PO4+MgSO4营养液作用显著,增产8.88%~9.30%,提高含糖率0.51~0.55个百分点(糖度),增加产糖量12.53%~13.25%;块根及糖分增长期,以喷施KH2PO4+Na2B4O7或KH2PO4+MnSO4营养液作用显著,增产5.89%~6.90%,提高含糖率0.85~1.04个百分点(糖度),增加产糖量12.31%~12.39%。其增产、增糖处理之作用与提高其光合性能,改善氮、磷和核酸营养水平,促进叶丛中糖分的积累与转化等有关,从而有利于块根的增长和糖分积累。为此,甜菜生育前期喷施KH2PO4+ZnSO4和生育后期喷施KH2PO4+Na2B4O7,是提高甜菜产量和含糖率的有效途径之一。     

Dehydrotomatine and alpha-tomatine content in tomato fruits and vegetative plant tissues

Tomato plants (Lycopersicon esculentum) synthesize the glycoalkaloids dehydrotomatine and alpha-tomatine, possibly as a defense against bacteria, fungi, viruses, and insects. We used a high-performance liquid chromatography method with UV detection at 208 nm for the analysis of these compounds in various tissues. An Inertsil ODS-2 column with a mobile phase of acetonitrile/20 mM KH2PO4 (24/76, v/v) afforded good separation of the two glycoalkaloids in mini-tomato extracts, fruit harvested at different stages of maturity, and calyxes, flowers, leaves, roots, and stems. The two peaks appeared at approximately 17 and approximately 21 min. Recoveries from tomato fruit extracts spiked with dehydrotomatine and alpha-tomatine were 87.7 +/- 6.8 and 89.8 +/- 3.4% (n = 5), respectively. The detection limit is estimated to be 0.39 microg for dehydrotomatine and 0.94 microg for alpha-tomatine. The dehydrotomatine and alpha-tomatine content of tomatoes varied from 42 to 1498 and 521 to 16 285 microg/g of fresh weight, respectively. The ratio of alpha-tomatine to dehydrotomatine ranged from 10.9 to 12.5 in tomatoes and from 2.3 to 7.8 in the other plant tissues. These results suggest that the biosynthesis of the glycoalkaloids is under separate genetic control in each plant part. Degradation of both glycoalkaloids occurred at approximately the same rate during maturation of the tomatoes on the vine. An Inertsil NH2 column, with acetonitrile/1 mM KH2PO4 (96/4, v/v) as the eluent, enabled the fractionation of commercial tomatidine into tomatidenol and tomatidine, the aglycons of dehydrotomatine and alpha-tomatine, respectively. The information should be useful for evaluating tomatoes and vegetative tissues for dehydrotomatine/alpha-tomatine content during fruit development and their respective roles in host-plant resistance and the diet.     

Flavor compounds of pine sprout tea and pine needle tea

Flavor compounds of pine sprout tea and pine needle tea were analyzed and identified in this study. Eighty-one and 39 kinds of flavor compounds were detected in pine sprout tea and pine needle tea by GC, respectively. Among them, 55 and 29 flavor compounds were identified by GC-MS, respectively. Major flavor compounds of pine sprout tea were alpha-pinene, myrcene, beta-thujene, terpinene-4-ol, and delta-cadinene, and major flavor compounds of pine needle tea were alpha-pinene, isoamyl alcohol, trans-caryophyllene, terpinene-4-ol, alpha-terpineol, and delta-cadinene.     

Comparison of oil recovered from tea tree leaf by ethanol extraction and steam distillation

Two methods for the determination of oil and oil major components from tea tree (Melaleuca alternifolia) leaf are quantitatively compared. A microwave assisted ethanol extraction and a 2-h hydrodistillation technique were used on both dry and fresh leaf from a low and a high oil concentration tree. There was no significant difference between dry and fresh leaf. The distillation technique recovered 88% and 82% of the extractable oil for the low and high concentration material, respectively. For both samples this distilled oil was composed of lower absolute amounts of sesquiterpenoids and marginally lower amounts of monoterpenoids. Extending the distillation to 6 h increased the sesquiterpenoid recovery but this resulted in a reduction in both the absolute and relative amounts of the oxygenated monoterpenoids, terpinen-4-ol and 1,8-cineole.     

Alkaloidal components in the poisonous plant,Ipomoea carnea (Convolvulaceae)

Natural intoxication of livestock by the ingestion of Ipomoea carnea (Convolvulaceae) sometimes occurs in tropical regions of the world. Polyhydroxylated alkaloids were isolated from the leaves, flowers, and seeds of the poisonous plant and characterized. Chromatographic separation of the leaf extract resulted in the isolation of swainsonine (1), 2-epi-lentiginosine (2), calystegines B(1) (3), B(2) (4), B(3) (5), and C(1) (6), and N-methyl-trans-4-hydroxy-l-proline (7). The contents of 1 in the fresh leaves and flowers were 0.0029 and 0.0028%, respectively, whereas the contents of 1, 3, and 4 in the seeds were approximately 10 times higher than those in the leaves and flowers. Alkaloids 3, 4, and 6 showed a potent inhibitory activity toward rat lysosomal beta-glucosidase, with IC(50) values of 2.1, 0.75, and 0.84 microM, respectively, and alkaloid 5 was a moderate inhibitor of alpha- and beta-mannosidases. Although alkaloid 1 is known as a powerful inhibitor of lysosomal alpha-mannosidase (IC(50) = 0.02 microM), alkaloid 2, which has been thought to be an intermediate in the biosynthesis of 1, was also a potent inhibitor of alpha-mannosidase with an IC(50) value of 4.6 microM.     

Screening of chemical composition and antifungal and antioxidant activities of the essential oils from three Turkish artemisia species

The compositions of essential oils isolated from the aerial parts of Artemisia absinthium, Artemisia santonicum, and Artemisia spicigera by hydrodistillation were analyzed by GC-MS, and a total of 204 components were identified. The major components of these essential oils were camphor (34.9-1.4%), 1,8-cineole (9.5-1.5%), chamazulene (17.8-nd%), nuciferol propionate (5.1-nd%), nuciferol butanoate (8.2-nd%), caryophyllene oxide (4.3-1.7%), borneol (5.1-0.6%), alpha-terpineol (4.1-1.6%), spathulenol (3.7-1.3%), cubenol (4.2-0.1%), beta-eudesmol (7.2-0.6%), and terpinen-4-ol (3.5-1.2%). The antifungal activities of these essential oils were tested against 11 plant fungi and were compared with that of a commercial antifungal reagent, benomyl. The results showed that all of the oils have potent inhibitory effects at very broad spectrum against all of the tested fungi. Pure camphor and 1,8-cineole, which are the major components of the oils, were also tested for antifungal activity against the same fungal species. Unlike essential oils, these pure compounds were able to show antifungal activity against only some of the fungal species. In addition, the antioxidant and DPPH radical scavenging activities of the essential oils, camphor, and 1,8-cineole were determined in vitro. All of the studied essential oils showed antioxidant activity, but camphor and 1,8-cineole did not.     

Comparison of Various Analysis Methods for Determination of Iron Chlorosis in Apple Trees

Abstract

The objective of this study was to compare iron (Fe) concentrations (mg kg^?1) of the leaves measured by different methods and to determine the most suitable method to be used in evaluation of iron chlorosis in apple trees. For this purpose, green and chlorotic leaves were collected from 76 apple orchards in 1998 and 1999. Iron concentrations (mg kg^?1) of dried leaf samples were measured with 4 different methods, 1 N HCl (Method 1), 0.1 N HCl (Method 2), 0.005 M DTPA (Method 3), and 1.5% o-phenanthroline (Method 4). Total Fe concentrations (mg kg^?1) of dried leaf samples were also analyzed. Total chlorophyll and peroxidase enzyme activity in fresh leaf samples were measured. The total chlorophyll, peroxidase enzyme activity, Fe concentrations (mg kg^?1) determined by Method 1, Method 3, Method 4, and total Fe concentrations (mg kg^?1) of green leaves were higher than those of chlorotic leaves. On the other hand, no significant difference was found between Fe concentrations (mg kg^?1) of green and chlorotic leaves, measured with Method 2. Significant relationship observed amongst chlorophyll concentrations, peroxidase enzyme activity, and Fe concentrations (mg kg^?1) of samples suggests that 1 N HCl method was the most suitable method amongst the methods used in this study for apple trees.     

Determination of organic acids in plants of Silene paradoxa L. by HPLC

According to the general behavior that organic acids steadily bind metals, a specific and highly reproducible HPLC separation method with photodiode array detection has been improved for their determination and quantification in biological materials. The separation was carried out on an Alltima C-18 reverse phase column. The mobile phase was 125 mM KH2PO4, adjusted to pH 2.5 with concentrated H3PO4, and optimum separation efficiency was obtained by using a 2 mL min(-1) flow rate. Detection wavelength for quantitative measurement was 210 nm. The run time of each sample was 20 min, with a spectra collection frequency of 5 spectra s(-1). Organic acids were identified by comparing the retention times of the samples against retention times of the standards and confirmed with spectral (190-700 nm) signature. Because organic acids could steadily bind metals in plant tissues and due to the strong matrix effect observed, the addition method was applied for quantitative analysis and its performance evaluated.     

Retention of alkamides in dried Echinacea purpurea

Different drying methods, such as freeze-drying (FD), vacuum microwave drying (VMD), and air-drying (AD), were applied to fresh roots and leaves of Canadian-grown Echinacea purpurea to determine the optimal method for preserving alkamide levels. Using HPLC, six alkamide fractions (alkamides 1, 2, 3, 6a/6, 7, 8/9) were quantitated in dried roots, whereas four alkamide fractions (alkamides 1, 2, 3, 8/9) were measured in dried leaves. Different elution conditions used in HPLC for alkamide analysis did not affect the eluted fractions nor the quantitation of different alkamides. Individual alkamide concentrations in roots and leaves were affected by the drying methods used. To preserve higher levels of total alkamides, FD was found to be the best method, VMD was a superior method for drying roots than AD at 70 degrees C, while AD at 50 degrees C was the preferred method for drying leaves of E. purpurea.     

Physiological and Biochemical Responses of French Bean to Excess Cobalt

ABSTRACT

French bean (Phaseolus vulgaris L.) cv. ‘Anupama’ was grown in refined sand at variable levels of cobalt (Co), i.e., 0.0001 (control), 0.05, 0.10, 0.20, 0.40, and 0.50 mM, supplied as cobalt sulfate. The symptoms of excess Co (0.50 mM) appeared at day 35. In addition to growth depression, the young leaves developed chlorosis from the apex leading toward the base; the chlorosis intensified, changed to necrosis, and the infected leaves dried and withered. Under excess Co (> 0.0001 mM), the flowers produced were fewer in number, smaller, and many failed to mature, leading to lower seed yield. Excess Co (> 0.0001 mM) decreased the biomass, seed yield (number and weight), concentration of chlorophyll, Hill reaction activity, and activity of catalase, and deteriorated the quality of produce (sugars, starch, and protein nitrogen (N)), but it increased the concentration of phenols and activity of certain enzymes, i.e., peroxidase, ribonuclease, and acid phosphatase. The concentration of Co in various parts of French bean increased with an increase in Co supply and that of iron (Fe) decreased concomitantly. The values of threshold of toxicity and toxicity of Co were 26 and 72 μg g^?1 in young leaves of French bean, respectively.     

Extraction of rutin from buckwheat (Fagopyrum esculentumMoench) seeds and determination by capillary electrophoresis.

The content of the flavonoid rutin was determined in different milling fractions of buckwheat seeds and in buckwheat stems, leaves, and flowers. The extraction was performed by using a solvent containing 60% of ethanol and 5% of ammonia in water. The extracts were analyzed by capillary electrophoresis (running buffer of 50 mM borate (pH 9.3), 100 mM sodium dodecyl sulfate; determination at 380 nm). In bran fractions the concentration of rutin was 131-476 ppm, and in flour fractions 19-168 ppm. On average, about 300, 1000, and 46000 ppm of rutin were found in leaves, stems, and flowers, respectively. The results indicate that buckwheat could be an important nutritional source of flavonoids, especially in countries with a low mean daily flavonoid intake.