Chemical composition and biological activities of essential oils of seven Cultivated Apiaceae species

The Apiaceae family contains many species used as food, spice and medicinal purposes. Different parts of plants including seeds could be used to obtain essential (EO) oils from members of the Apiaceae family. In the present study, EOs were components obtained through hydrodistillation from the seeds of anise (Pimpinella anisum), carrot (Daucus carota), celery (Apium graveolens), dill (Anethum graveolens), coriander (Coriandrum sativum), fennel (Foeniculum vulgare), and cumin (Cuminum cyminum). EO constituents were determined with Gas Chromatography/Mass Spectrometry (GC-MS) and Gas Chromatography/Flame Ionization Detector (GC-FID) and their antioxidant capacities were determined with the cupric reducing antioxidant capacity (CUPRAC) and 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) methods. The antimicrobial activity of EOs were tested against four pathogenic bacteria. Phenylpropanoids in anise (94.87%) and fennel (92.52%), oxygenated monoterpenes in dill (67.59%) and coriander (98.96%), monoterpene hydrocarbons in celery (75.42%), mono- (45.42%) and sesquiterpene- (43.25%) hydrocarbons in carrots, monoterpene hydrocarbon (34.30%) and aromatic hydrocarbons (32.92%) in cumin were the major compounds in the EOs. Anethole in anise and fennel, carotol in carrot, limonene in celery, carvone in dill, linalool in coriander, and cumin aldehyde in cumin were predominant compounds in these EOs. The high hydrocarbon content in cumin EO gave high CUPRAC activity (89.07 µmol Trolox g-1), and the moderate monoterpene hydrocarbon and oxygenated monoterpene content in dill EO resulted in higher DPPH activity (9.86 µmol Trolox g-1). The in vitro antibacterial activity of EOs against Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli was evaluated using the agar diffusion method and the minimum bactericidal concentration was determined. Coriander, cumin and dill EOs showed inhibitory effect against all tested strains except P. aeruginosa. While fennel and celery EOs were effective against E. coli and B. cereus strains, respectively, anise and carrot EOs did not show any antibacterial effect against the tested bacteria. Hierarchical Cluster Analysis (HCA) produced four groups based on EO constituents of seven species. The potential adoption of the cultivated Apiaceae species for EO extraction could be beneficial for the wild species that are endangered by over collection and consumption.

Variation in antioxidant capacity, antioxidant activity and mineral composition during flower development of oil-bearing rose (Rosa damascena Mill.)

Oil-bearing rose is an economically important rose species with a wide range of uses such as cosmetics, perfumery, food and health, but the changes in antioxidant capacity and antioxidant activity during flower development are not well understood. The antioxidant content and free radical scavenging properties of oil-bearing rose flowers are used in the cosmetic industry to modulate skin damage, and in the food industry as a source of antioxidants and sweeteners. The present investigation was carried out to explore the antioxidant capacity, antioxidant enzyme activity, and the composition and distribution of minerals in petals of oil-bearing rose at five flower development stages. The total antioxidant capacity of petals was determined using CUPRAC, DPPH, FRAP, FIC and ABTS methods. The antioxidant capacity of petals decreased during the flower development, suggesting that flowers in stage I and II are valuable sources of antioxidants. CUPRAC, DPPH, FRAP, FIC and ABTS scavenging activity of the petals at various developmental stages are strongly and positively correlated with each other. The activity of the antioxidant enzymes; superoxide dismutase, catalase, glutathione reductase, ascorbate peroxidase was highest at the bud stage (stage I), whereas the fully opened flowers (stage V) exhibited the lowest activity in oil-bearing rose petals. During the development of flower, malondialdehyde (MDA) content increased significantly from stage I to stage III and decreased at stage IV. Here we detected the contents of 15 elements in petals, some of them, especially calcium, magnesium, potassium and phosphorus showed significant changes during rose flowering. Generally, the highest mineral content was observed in stage I while the lowest content observed in stage V of flower development. These results showed a close link between flower development, antioxidant capacity, enzymatic antioxidant activity and mineral content, with stage I exhibiting the best antioxidant activity, mineral content and free radical scavenging potential. This work will serve as a baseline for understanding the possible roles of antioxidant capacity, antioxidant enzymes, mineral content and their interactions in the regulation of flower development.

Cell wall composition and enzyme-related activities in eggplant as affected by hot water, 1-MCP and calcium chloride treatments

The effects of postharvest applications of hot water (HWT) (45, 50, and 55 °C), 1-MCP (1, 5, and 10 μL/L), and CaCl2 (1, 2, and 3%) on polygalacturonase (PG), pectin methylesterase (PME), α-galactosidase (α-Gal), β-galactosidase (β-Gal) and β-1,4-glucanase (β-1,4-Glu) activities, and the fruit firmness and cell wall composition of eggplant fruit were investigated. The results showed that the decrease in the eggplants firmness was delayed by HWT, 1-MCP, and CaCl2 treatments during storage compared with the control. However, HWTs were less effective than the 1-MCP and CaCl2 treatments. The results show that 1-MCP and CaCl2 treatments inhibited the depolymerization of water (WSP), CDTA (CSP), and sodium carbonate (SSP) soluble polyuronides. The results suggest that 1-MCP (5 and 10 μL/L) and CaCl2 (1, 2, and 3%) could prevent eggplant softening by inhibiting hydrolase enzymes and reducing the disintegration of the polysaccharides. In addition, 1-MCP and CaCl2 were more effective than hot water treatment in extending postharvest storage life. There is a significantly high correlation between firmness, polyuronide content and cell wall enzyme activity.

Dynamic changes occur in the cell wall composition and related enzyme activities during flower development in Rosa damascena

The flowering period of oil-bearing rose is short and many physiological processes occur during flower development. Changes in the cell wall composition and associated enzyme activities are important as they allow cells to divide, differentiate and grow. In the present study, changes in seven cell wall components and six cell wall-related enzyme activities at five flower development stages were investigated and the relationships between these parameters and flowering were examined. Ash content did not change between stages I to II but decreased at later stages. Neutral detergent fiber (NDF), acid detergent fiber (ADF) and hemicellulose contents increased after stage I but did not change significantly at the other developmental periods. Total pectin content increased throughout flower development. An "increase-decrease" trend was observed in total cellulose content and a "decrease-increase" pattern in uronic acid content. The activities of both glycosidases (β-galactosidase, β-glucosidase and endoglucanase) and pectinases (pectin lyase, pectin methyl esterase and polygalacturonase) increased until stage IV and decreased significantly at stage V of flower development. Correlation analysis revealed 14 positive and one negative correlation with the studied parameters. Cell wall enzymes showed positive correlations with each other. Principal component analysis (PCA) showed that ADF, NDF and cellulose content were significantly altered at stage II of flower development, and significant changes occurred in all cell wall enzyme activities between stages III and V. Overall, blooming is correlated closely with increased pectin and decreased cellulose contents, and changes in cell wall glucosidase and pectin hydrolysis enzyme activities. These results show that cell wall modifying enzymes are part of the flower development process in oil-bearing rose. Therefore, remodeling of cell wall components in petals is a process of flower development.

Investigation of phenological, primary and secondary metabolites changes during flower developmental of Rosa damascena

Oil-bearing rose is a very valuable member of the Rosa genus. Despite the importance of oil-bearing rose, metabolic changes during flower development are not well understood. Thus, the objective of this study was to investigate the changes in phenological, primary and secondary metabolites and their interactions at five developmental stages of oil-bearing rose. Flower width, flower and petal fresh weights, petal area and petal relative water content increased from bud stage to blooming stage, while flower length and sepal area increased only at early stages. Thirty-seven essential oil components were identified at different stages of petal development and nonadecane, β-citronellol and n-heneicosane were the prevalent essential oil components regardless of stage. Sixteen fatty acids were identified and the amount of saturated fatty acids was higher than the mono and polyunsaturated fatty acids in all developmental stages. Eight organic acids were detected in petals and four of them (tartaric, malic, citric and succinic acids) showed significant changes, and total organic acids content decreased during flower development. Catechin and epicatechin were the most abundant phenolic compounds in petals. While total phenolic, flavonoid and free amino acids contents decreased during flower development, total free fatty acids content increased, but was not significant between the developmental stages. Correlation analysis between phenological traits and some metablolites revealed 20 significant correlations and 11 of which were positive. Results showed that flower development stages had significant effects on metabolite content and quality of products obtained, and significant shifts in metabolite type and content occurred at flower development stages III and IV.