Cultivar characterization of Aegean olive oils with respect to their volatile compounds

Cultivar characterization of Aegean olive oils (cv. Ayvalik and Memecik) based on their volatile compounds was carried out. The main volatile compounds detected in the Aegean olive oils were the C6 compounds derived from polyunsaturated fatty acids through the lipoxygenase pathway. The C6 aldehydes and C6 alcohols contributing to the green and fruity sensory notes of olive oil were determined in the Aegean olive oils as the major volatile compounds. Significant differences in the levels of hexanal, (E)-2-hexenal, 3-ethyl-1,5-octadiene and total compounds from linolenic acid were observed between Ayvalik and Memecik oils (p < 0.01). Principal component analysis (PCA) and linear discriminant analysis (LDA) were applied to process the experimental data. The results of the chemometric analysis revealed that the two cultivars were clearly discriminated on the PC1–PC3 planes and LDA produced a 100% correct group classification.     

Assessment of volatile and non-volatile organic compounds in the liquid endosperm of young ‘Nam Hom’ coconut (Cocos nucifera L.) at two stages of maturity

SUMMARY

Young coconut (Cocos nucifera L.) fruit collected 6–8 months after anthesis (MAA) contain a high volume of water [20% (w/w)] and can provide a refreshing drink. The present study investigated volatile organic compounds (VOCs), as aroma components, and physico-chemical changes in the liquid endosperm of young ‘Nam Hom’ coconut at two stages of maturity: the one-layer stage (6 MAA) and the two-layer stage (7.0–7.5 MAA) of the flesh. The liquid endosperm of coconut fruit becomes sweeter and more turbid late during maturation. Lauric acid (C_12:0) and myristic acid (C_14:0) were the main free fatty acids in the liquid endosperm of coconut. Short-chain fatty acid (C₁₀–C₁₂) concentrations increased slightly, and longer-chain fatty acid (C₁₄–C₁₈) concentrations declined when fruit matured from the one- to the two-layer stage of flesh. Solvent extractions showed a 1.4-fold increase in the total concentration of VOCs in the liquid endosperm during fruit development. This was related to a major increase in squalene and sterols, to 21.7% (w/w) of the total VOC and non-volatile organic compounds, whereas the concentrations of terpenes and esters remained stable. Although a series of alkanes existed in the liquid endosperm of coconut, the main aroma components were 2-methyl-1-butyl acetate and terpenes such as D-limonene, α-pinene, and 3-carene. We conclude that, when coconut fruit developed from the one- to the two-layered flesh stage, the liquid endosperm not only became sweeter and contained higher concentrations of aroma volatile and non-volatile components, but also became oily and less translucent.     

Chemical compositions and insecticidal effects of essential oils isolated from Achillea gypsicola, Satureja hortensis, Origanum acutidens and Hypericum scabrum against broadbean weevil (Bruchus dentipes)

The essential oils of aerial parts of Achillea gypsicola Hub.-Mor., Hypericum scabrum L., Satureja hortensis L., and Origanum acutidens (Hand.-Mazz.) Letswaart were analyzed in this study by GC and GC–MS and their oils were tested for toxicity against broadbean weevil (Bruchus dentipes). A. gypsicola oil contained camphor (40.17%), 1,8-cineole (22.01%), piperitone (11.29%), borneol (9.50%) and α-terpineol (1.56%) as major components. A total of 74 components were identified by GC–MS in H. scabrum oil, including α-pinene (9.26%), terpinen-4-ol (5.12%), camphor (5.94%), δ-cadinene (4.52%), pulegone (4.45%), γ-muurolene (4.12%), pinocarvone (3.97%) and β-caryophyllene (3.42%) as predominant components. The essential oils of O. acutidens and S. hortensis were characterized by high contents of carvacrol (86.99% and 55.74%), γ-terpinene (0.71% and 20.94%), p-cymene (1.95% and 12.30%), α-terpinene (0.13% and 2.04%) and β-caryophyllene (1.30% and 1.08%). All of the essential oils were toxic to adults of B. dentipes and insect mortality increased with increasing concentration of each oil. The oils (20 μl dose) brought about 100% mortality in 36 h. Although desirable insecticidal activities against the pest were achieved with the oils from all four plant species, S. hortensis and O. acutidens oils were more effective, particularly after 6 h of treatment. The current results concluded that the essential oils, in particular O. acutidens and S. hortensis oils, may be used as potential botanical insecticides against B. dentipes.     

Regional and maturational effects on essential oils yields and composition of coriander (Coriandrum sativum L.) fruits

The composition of volatile components of the essential oils extracted from fruits of coriander (Coriandrum sativum L.) growing in two different Tunisian regions in both Menzel Temime and Borj El Ifaa was studied by GC and GC–MS. The highest oil yields were observed at final stages of maturity: 0.324 ± 0.09% and 0.327 ± 0.08%, in Menzel Temime and Borj El Ifaa, respectively. Essential oil yields were highly (P < 0.001) affected by the growing region, stages of maturity and their interaction. Essential oil composition changed significantly (P < 0.05) among the different stages of maturity and growing region. Linalool and geranyl acetate were the main compounds at full fruit maturity in the two studied regions. Growing region, stages of maturity and their interaction had a strong effect (P < 0.001) on 35 compounds. α-Pinene, sabinene, limonene, γ-terpinene, cis-dihydrocarvone and geranial were insensible to the regional factor.     

Identification of Petunia hybrida cultivars that diurnally emit floral fragrances

In order to identify genetic resources for breeding fragrant petunias for use as bedding plants, volatile compounds released by day from the flowers of 40 commercial Petunia hybrida cultivars were analyzed using a solid-phase micro-extraction technique coupled with GC–MS. The three cultivars with solid deep-blue flowers that accumulate malvidin in corollas with high tissue pH were found to emit abundant iso-eugenol as the principal floral fragrance. Several other cultivars that emitted considerable amounts of methylbenzoate and/or benzylbenzoate from the flower were also identified. Association between the floral fragrance and the other floral traits such as floral anthocyanin composition and corolla-tissue pH was discussed.     

Compositional quality of virgin olive oils from cultivars introduced in Tunisian arid zones in comparison to Chemlali cultivars

This work is an evaluation of the quality of three introduced European olive cultivars Arbequina, Coratina, and Koroneiki grown under a biological agricultural system in the arid zone of Sfax in Tunisia compared to Chemlali cultivars. Various olive parameters were analyzed, such as ripening index, pulp/stone (P/S) ratio and oil content. We have considered the regulated physicochemical analytical parameters, fatty acids and minor compounds for olive oil. The most of the quality indices and fatty acid composition showed significant variations among olive cultivars. The Koroneiki, Coratina and Chemlali Zarzis cultivars had highest values of oleic acid (62.7%) (76.8%, 75.8% and 73.9%, respectively), Arbequina, had lowest value of oleic acid and similar to Chemlali Sfax. Coratina was noteworthy for its higher content of phenolic compounds (287.8 mg kg⁻¹), oil content (42.4%) and P/S ratio (4.7%). Although their low phenol contents, autochthonous cultivars presented high contents of α-tocopherol (577.8 and 434.6 mg kg⁻¹ for Chemlali Boughrara and Chemlali Zarzis, respectively) except for Chemlali Sfax. In conclusion, European cultivars seem to have adapted to the area studied according to their oil biochemical composition while the increase observed in their α-tocopherol levels. The cultivar Arbequina showed a similar composition of Chemlali Sfax.     

金银花和红银花挥发性成分的顶空固相微萃取#br# 气质联用检测与比较

 采用顶空固相微萃取气质联用（SPME–GC–MS）的方法检测红银花与金银花新鲜花蕾和 干花蕾的挥发性成分。4 种花蕾样品共鉴定出67 种挥发性物质,其中新鲜红银花与金银花分别检测出48 种和46 种,经烘干处理的干红银花与金银花分别检测出34 种和37 种。[3.2.1.0（1,5）]三环辛烷、β– 芳樟醇、5–甲基–2–己醇和以及十六烷是4 种样品共有的成分。其中红银花挥发性成分主要以烃类、 醇酮类为主,β–芳樟醇含量显著高于金银花;样品在由新鲜到烘干这一过程中,烃类和酯类挥发性物质 含量降低,醛类和醇酮类挥发性物质显著增加。     

厚皮甜瓜(Cucumis melon)鲁厚甜2号香气成分的GC-MS分析

采用顶空固相微萃取方法对厚皮甜瓜鲁厚甜2号香气进行富集,经GC-MS联机检索分析,得到107种挥发性组分,初步鉴定出79种,其中酯类有29种、醇类9种、醛类6种、酮类3种、酸类4种、烷烃类20种和其他8种化合物成分。鲁厚甜2号主要香气成分有乙酸苯甲酯、n-软脂酸、2-苯基乙酸乙酯、2-甲基乙酸-1-丁醇、硬脂酸、异丙氧基氨基甲酸乙酯和乙酸己酯等,它们占峰总量的46.72%,对甜瓜的整体香气有关键性影响。     

Bacterial canker of olives caused by of Pseudomonas syringae pv. syringae in Iran

Guilan is one of the main province olive oil producers in Iran. The culture of olive trees is of considerable importance. One problem that affects Iran olive orchards is a disease bacterial canker caused by Pseudomonas syringae pv. syringae. In this research, the bacterium was recovered from sunken brown stem lesions on 2-year-old olive trees cv. Marie, during survey from olive orchards in different areas of Guilan province. Samples were taken from infected tissues and were washed with sterile distilled water and crushed in peptone water. Then 50 μl of the extract was cultured on NA and King's B medium containing cyclohexamid antibiotic (50 μg/ml). After 48–72 h, bacterial colonies were selected. Based on morphological, physiological, biochemical, pathogenicity properties and PCR methods with specific primers the predominant pathogenic type was identified as P. s. pv. syringae. This is the first report of the existence of P. s. pv. syringae on olive trees in Iran.     

Acetonitrile (methyl cyanide) emitted by the African spider plant (Gynandropsis gynandra L. (Briq)): Bioactivity against spider mite (Tetranychus urticae Koch) on roses

The African spider plant (Gynandropsis gynandra L. (Briq)) has repellent properties against spider mite on roses (Rosa hybrida L.) when grown as a companion plant. Gas chromatography–mass spectrometry (GC–MS) has been used to identify potential volatile compounds in the foliar emissions of this plant that may contribute to the anti-mite properties. Acetonitrile (methyl cyanide) was the most abundant compound emitted by entire plants and detached leaves of five lines of both glasshouse- and field-grown G. gynandra, with only trace levels emitted by roses grown under similar conditions. A toxicity bioassay was conducted to evaluate the bioactivity of acetonitrile against spider mite, and ≥2.5 μL/L of air rendered 100% of the mites inactive. Removal of the compound after an initial exposure of up to 5.0 μL/L of acetonitrile allowed some 10% of the mites to recover mobility, but above this level no mobility was observed. This study provides a very strong indication that foliar emissions of acetonitrile by G gynandra are responsible, to a significant degree, for the spider mite repellent activity of the plant when used as an intercrop with roses.     

A Report on Field Trials with 3: 5-Dinitro-O-Cresol and its Sodium Salt for Winter Spraying.

Summary

Uniformly green mature `Kensington Pride' mangoes (Mangifera indica L.) were ripened at ®ve temperatures (158C, 208C, 25, 30 or 358C) with 60% r.h. to investigate the effects of ripening temperature on the ripening process and biosynthesis of aroma volatile compounds. The aroma volatile compounds were extracted by headspace solid phase micro-extraction and analysed using a gas chromatograph (GC) ®tted with a ¯ame ionization detector (FID) and recon®rmed by GC-MS (mass spectrometry). An increase in the temperature signi®cantly increased the rate of respiration and total carotenoids in pulp. Increased ripening temperature up to 308C also increased ethylene production in fruit and total fatty acids in pulp. All the fatty acids in pulp increased as the ripening temperature increased during ripening except palmitic, palmitoleic and linolenic acids. However, pulp of the fruit ripened at 258C exhibited signi®cantly higher concentrations of individual fatty acids, except stearic and linoleic acids. Fruit ripened at 208C exhibited signi®cantly higher total monoterpenes, sesquiterpenes as well as most of their individual compounds as compared with all other ripening temperatures. Increased ripening temperature resulted in signi®cantly higher concentrations of tetradecane, b-ionone, esters and alcohols. On the other hand increased ripening temperature tended to decrease aromatics and aldehydes except carvacrol, p-cymen-8-ol and hexanal. There were signi®cant positive correlations between fatty acids and sesquiterpenes, alcohols and esters especially on day seven of ripening. A signi®cant positive correlation between carotenoids and norisoprenoids was also recorded. A ripening temperature of 208C seems to be the best for ripening and biosynthesis of aroma volatile compounds in the `Kensington Pride' mango.     

不同栽培方法银耳挥发性成分的HS-SPME/GC-MS分析

采用顶空固相微萃取分别提取椴木银耳、袋栽银耳的挥发性成分,采用GC-MS法分析样品的挥发性成分,采用相对气味活度值(ROAV)判定关键风味物质。从椴木银耳中检出51种挥发性成分,主要是酸类、醛类、醇类化合物,相对含量最高的是乙酸,占比21.212%。从袋栽银耳中检出58种挥发性成分,主要是醛类、酸类、醇类化合物,相对含量最高的是正己醛,占比13.173%。采用ROAV法进行评价,得出椴木银耳的关键风味物质包括正己醛、辛醛、壬醛、蘑菇醇、庚醛、正庚酸、肉桂醛、正戊醛,共8种。袋栽银耳的关键风味物质包括壬醛、正己醛、辛醛、蘑菇醇、正戊醛、庚醛,共6种。     

Does root-sourced ABA play a role for regulation of stomata under drought in quinoa (Chenopodium quinoa Willd.)

The Andean seed crop quinoa (Chenopodium quinoa Willd.) is traditionally grown under drought and other adverse conditions that constrain crop production in the Andes, and it is regarded as having considerable tolerance to soil drying. The objective of this research was to study how chemical and hydraulic signalling from the root system controlled gas exchange in a drying soil in quinoa. It was observed that during soil drying, relative g_s and photosynthesis A_max (drought stressed/fully watered plants) equalled 1, until the fraction of transpirable soil water (FTSW) decreased to 0.82 ± 0.152 and 0.33 ± 0.061, respectively, at bud formation, indicating that photosynthesis was maintained after stomata closure. The relationship between relative g_s and relative A_max at bud formation was represented by a logarithmic function (r² = 0.79), which resulted in a photosynthetic water use efficiency WUE_Amax_/gs$\text{WU}{\text{E}}_{A_{\text{max}}/g_{\text{s}}}$ of 1 when FTSW > 0.8, and increased by 50% with soil drying to FTSW 0.7–0.4. Mild soil drying slightly increased ABA in the xylem. It is concluded that during soil drying, quinoa plants have a sensitive stomatal closure, by which the plants are able to maintain leaf water potential (ψ_l) and A_max, resulting in an increase of WUE. Root originated ABA plays a role in stomata performance during soil drying. ABA regulation seems to be one of the mechanisms utilised by quinoa when facing drought inducing decrease of turgor of stomata guard cells.     

Response of “Sangiovese” grapevines to partial root-zone drying: Gas-exchange,growth and grape composition

Our study focuses on the physiological response and yield-quality performance of split-root potted Sangiovese grapevines under a partial root-zone drying (PRD) regime from pre-veraison to harvest by withholding water from one of the two pots and comparing the results to a well-watered control (WW). While predawn water potential (ψ_pd) tended to equilibrate in PRD with the soil moisture level of the wet pot, both stem (ψ_st) and mid-day leaf-water potential (ψ_l) were markedly lower in PRD as compared to WW vines, indicating that Sangiovese shows anisohydric response. On the other hand, the seasonal reduction of leaf assimilation rate (A) in PRD over the 6-week stress period versus WW was 16% as compared to a 41 and 25% for leaf stomatal conductance (g_s) and transpiration (E), respectively. As a consequence, intrinsic WUE (A/g_s) was markedly increased in the half-stressed vines, suggesting a response more typical of an isohydric strategy. Shoot growth was promptly checked in PRD vines, which had no limitation in yield and better grape composition as per soluble solids and total anthocyanins. These responses occurred in spite of sub-optimal leaf photosynthesis rates and lowered leaf-to-fruit ratio and qualify Sangiovese as a good candidate for adapting to regulated deficit irrigation strategies.     

Root restriction-induced limitation to photosynthesis in tomato (Lycopersicon esculentum Mill.) leaves

Root restriction often depresses photosynthetic capacity and the mechanism for this reduction, however, remains unclear. To identify the mechanism by which root restriction affects the photosynthetic characteristics, tomato (Lycopersicon esculentum Mill.) seedlings were subjected to root restriction stress with or without supplemental aeration to the nutrient solution. With the development of the root restriction stress, CO₂ assimilation rate was decreased only in confined plants without supplemental aeration. There were also significant decreases in leaf water potential, stomatal conductance (g_s), intercellular CO₂ concentration (C_i), and increases in the stomatal limitation (l) and the xylem sap ABA concentration. Meanwhile, the maximum carboxylation rate of Rubisco (V_cmax) and the capacity for ribulose-1,5-bisphosphate regeneration (J_max) also decreased, followed by substantial reductions in the quantum yield of PSII electron transport (Φ_PSII). Additionally, root restriction resulted in accumulation of carbohydrates in various plant tissues irrespective of aeration conditions. It is likely that root restriction-induced depression of photosynthesis was mimicked by water stress.     

Relationship between the oil and sugar content in olive oil fruits from Moraiolo and Leccino cultivars during ripening

In our previous work (Cherubini et al., 2009), sugar concentration was proposed as an accurate, reproducible index for technological ripening of olive oil fruits. During 2009 crop season, sugar and oil content of olive oil fruits from Moraiolo and Leccino cultivars were measured during ripening. The sugar content of olive oil fruits was determined both by titration and by using a portable refractometer.     

Photosynthetic characteristics and protective mechanisms against photooxidation during high temperature stress in two citrus species

Exposure of Satsuma mandarin (Citrus unshiu Marc.) and Navel orange (Citrus sinensis Osbeck) plants to high temperature (38 °C) led to reductions of the net photosynthetic rate (Pn), the photorespiration rate (Pr), the quantum efficiency CO₂ assimilation (ΦCO₂${\Phi }_{\text{C}{\text{O}}_2}$), the maximal photochemical efficiency of PS2 (Fv/Fm), the photochemical quenching (qP) and the quantum efficiency of PS2 photochemistry (Φ_PS2), whereas the minimal fluorescence yield (Fo) and the non-photochemical quenching (qN) increased. Increase in the value of Pr/Pn and ΦPS₂/ΦCO₂${\Phi }_{\text{PS}2}/{\Phi }_{\text{C}{\text{O}}_2}$ was attributed to the greater decrease in Pn and ΦCO₂${\Phi }_{\text{C}{\text{O}}_2}$ than Pr and Φ_PS2. In addition, the superoxide radical (O₂⁻) production, the H₂O₂ concentration and the activities of antioxidant enzymes such as the superoxide dismutase (SOD, EC 1.15.1.1), the ascorbate peroxidase (APX, EC 1.11.1.11), the dehydroascorbate reductase (DHAR, EC 1.8.5.1) and the catalase (CAT, EC 1.11.1.6) were raised. On the other hand, the chlorophyll concentration in leaves decreased during high temperature stress. These results suggest that decline in Pn related to inactivation of PS2 reaction centers may be due to the enhanced number of active oxygen species in the citrus leaves. The water–water cycle may play a role in limiting the degree of photodamage caused by high temperature. Lower O₂⁻ production rate, the H₂O₂ concentration and the antioxidant enzymes activity were observed in high temperature tolerant species of citrus. The exogenous active oxygen scavenger ascorbic acid (Asc) enhanced the ability to clear the O₂⁻ in citrus plants, and quicken the recovery of photosynthetic apparatus.     

固相微萃取-气相色谱-质谱联用法分析樟芝发酵液、液体发酵菌丝体和固体培养菌丝体中香气成分

采用固相微萃取-气相色谱-质谱联用分析樟芝(Taiwanofungus camphoratus)发酵液、液体发酵菌丝体和固体培养菌丝体中挥发性成分,其中共鉴定出30种香气成分.发酵液中有14种香气成分,相对含量为43.76％,以醇类为主;液体发酵菌丝体有19种香气成分,相对含量为34.97％,以醇类和醛类为主;固体培养菌丝体中有15种香气成分,相对含量为12.21％,以醛类为主.     

The effect of waste water irrigation on the extra virgin olive oil quality from the Tunisian cultivar Chemlali

The availability of fresh water is very scarce in the Middle East and North Africa. Yet consequently, brackish water or recycled wastewater can be used for irrigation, minimising the exploitation of natural water resources. The aim of this work was to study how irrigation with treated wastewater (TWW) over 4 years affects some parameters of “Chemlali” olive oil quality. Two treatments were considered: trees irrigated with treated wastewater and others cultivated in rain-fed conditions. Results showed that irrigation with TWW over 4 years did not affect free acidity, and specific ultraviolet absorbance at K₂₃₂ and K₂₇₀. For both the crop seasons the mean values of these parameters were lower than the upper limits established for “extra virgin” olive oil. However, irrigation with TWW cumulatively increased palmitic, palmitoleic, linoleic and linolenic acid contents and decreased oleic acid rates. A significant decrease of total phenol contents was also observed at the end of experimental period.