Improving postharvest quality and vase life of cut rose flowers by pre-harvest foliar co-applications of γ-aminobutyric acid and calcium chloride.

Rose flowers (Rosa hybrida L.) are highly perishable and have a limited vase life. This study evaluated the effects of preharvest foliar applications of γ-aminobutyric acid (GABA) and calcium chloride (CaCl2), individually and combined, on antioxidant responses and vase life of cut Jumilia rose flowers. Treatments included foliar sprays of GABA at 0, 20, 40, and 60 mM and CaCl2 at 0, 0.75%, and 1.5%, applied in a factorial design within a completely randomized setup before harvest. Results showed GABA and CaCl2 interaction (especially, 60 mM GABA and 1.5% CaCl2) significantly increased enzymatic antioxidants including superoxide dismutase, catalase, and peroxidase, as well as non-enzymatic antioxidants such as flavonoids, carotenoids, phenolics, and antioxidant activity in petals compared to control. SOD activity in roses, treated with CaCl2 (1.5%) and GABA (60 mM), peaked at 7.86 units. mg-1 protein min-1, showing a nearly 2.93-fold increase over the control (2.68 units. mg-1 protein min-1). A parallel trend was observed for CAT activity. These treatments also reduced petal malondialdehyde content and polyphenol oxidase activity. Protein content and vase life duration increased in all treatments. Plants treated with a combination of GABA (20 mM) and CaCl2 (0.75%), GABA (60 mM) and CaCl2 (1.5%), or GABA (40 mM) individually exhibited the longest vase life duration. The co-application of GABA and CaCl2 improved the antioxidant activity and postharvest quality of cut roses by reducing PPO activity and MDA contents, increasing protein content and prolonging vase life. This treatment is a potential postharvest strategy to improve antioxidant capacity and delay senescence in cut roses.

Effect of nanocomposite alginate-based edible coatings containing thymol-nanoemulsion and/or thymol-loaded nanostructured lipid carriers on the microbial and physicochemical properties of carrot.

In this study, the effect of thymol-nanoemulsion (NE) and thymol-loaded nanostructured lipid carriers (NLC) on the physiological and microbial quality of carrot was investigated. The NE and NLC droplet sizes were 86 and 140 nm with encapsulation efficiency of 97 and 94 %, respectively. The minimum inhibitory concentration and minimum bactericidal concentration of thymol decreased in NE and increased in NLC against E. coli and S. aureus. Moreover, thymol-containing coatings exhibited a higher peroxidase activity, total phenolic content, flavonoid content, DPPH radical scavenging activity, pH, and lower respiration rate, TSS, weight loss, and decay with the preference for samples coated with NLC and NE (particularly NLC). The NE and NLC treatments significantly reduced the total viable, mold and yeast, lactic acid bacteria, and Enterobacteriaceae counts compared to the free thymol-containing coating. Results showed that the application of NE and NLC containing alginate-based coating (with the preference for NLC) improved the postharvest quality of carrot and extended its shelf life. Meanwhile, the separate application of these systems gave better results than the simultaneous application of both systems in one sample.

Exogenous Putrescine Changes Biochemical (Antioxidant Activity, Polyphenol, Flavonoid, and Total Phenol Compounds) and Essential Oil Constituents of Salvia officinalis L.

Polyamines are small polycationic molecules containing amines that are present in almost all cells of living organisms and act in a wide range of physiological processes, growth, and development, biological and protection of cells against free radicals. This research is based on principal component analysis (PCA) and calculation of selection criteria (SC) to investigate the effect of foliar spraying of polyamine putrescine on essential oil yield, essential oil compounds, antioxidant activity, and biochemical compounds (polyphenol, flavonoid, and total phenol compounds) of Salvia officinalis. The treatments used included four levels of putrescine, Put (Control: 0, Put1: 500, Put2: 1000, and Put3: 1500 mg L-1 ) with five replications. Based on our results, four factors had eigenvalues≥1 and showed a cumulative variance percentage of 92.57 % by applying different concentrations of putrescine. According to the results of this research, putrescine had significant effects on the amount of total phenolic compounds, flavonoids, and antioxidant activity. The best attention to improving the essential oil yield of sage was 1000 mg L-1 . The crucial essential oil compounds of different Put treated sage were: cis-thujone (35.34 %), camphor (15.60 %), trans-thujone (9.90 %), 1,8-cineole (9.46 %), α-humulene (3.85 %), viridiflorol (3.62 %), camphene (3.58 %), α-pinene (3.50 %), ß-pinene (2.78 %), and limonene (1.23 %). The results showed that the amount of total phenol, the phenolic composition of catechin, and the antioxidant activity of sage plant extract increased significantly when putrescine was used at 1000 mg/liter. Results can use the current research to optimize the production management of medicinal plants and improve the quality of their products. In addition, the advantage of using putrescine is that it increases antioxidants and reduces oxidative damage, and can replace medicinal plants as suitable natural preservatives, thus improving food quality and safety.

Evaluation of pharmaceutical compounds at vegetative and reproductive growth stages of Marrubium vulgare, a medicinal plant to cleanse the body.

Marrubium vulgareis a plant with high bioactive potential. The rich bioactive compounds of medicinal horehound, as well as their antioxidant activity have led to its wider application in the pharmaceutical, cosmetic, and food industries. The present work aimed to determine the phenolic compounds, total phenols, flavonoids, and antioxidant activity at vegetative and reproductive growth stages of Marrubium vulgare. The experiments were performed in Eram Garden with five replications and using SPSS software (v. 13) and Mann-Whitney U-Test at p ≤ 0.01. The total content of flavonoids and main phenolic compounds increased when plants collected at vegetative stage. On the other hand, the highest vanillin content was observed in full flowering stage. Overall, this study can provide useful information about the best harvest period for horehound to produce the desired compounds for use in the food, pharmaceutical, and plant industries.

Essential oil composition and antioxidant activity of citron fruit (Citrus medica var. macrocarpa Risso.) peel as relation to ripening stages.

Stages of maturity have decisive roles in determining the quality and quantity of essential oil (EO). In this regard, EO yield and composition and their antioxidant activity of citron fruit at four fruit maturity stages, i.e. the green mature (GM), intermediate (INT), yellow ripe (MAT) and overripe stage (OR) were studied. Obtained results showed significant effect of fruit maturity on most measured properties. The concentration of EO varied between 0.60 and 0.77% (v/w). The highest amount of limonene was 89.39% related to GM stage. The limonene decreased significantly during maturity. The highest antioxidant activity (76.08%) was measured at the OR stage, which is probably due to the presence of specific compounds in the EO and their synergistic effects. The phytochemical behaviors of this citron variety were different as relation to stages of fruit maturity. We can determine the ideal harvest period for maximum bioactive substances by recognizing these actions.

Comparison monoterpene and sesquiterpene, herbage yield of Satureja hortensis, Thymus vulgaris, and Salvia officinalis from the Fars province of Iran.

Recently, numerous side effects of synthetic drugs have led to using medicinal plants as a reliable source of new therapy. Pain is a global public health problem with a high impact on life quality and a huge economic implication, becoming one of the most important enemies in modern medicine. The medicinal use of plants as analgesic or antinociceptive drugs in traditional therapy is estimated to be about 80% of the world population. The lamiaceae family, one of the most important herbal families, incorporates a wide variety of plants with biological and medical applications. In this study, the main active compounds of Thymus vulgaris (thymol (51.59%), p-cymene (15.41%), carvacrol (4.52%) and γ-terpinene (12.63%), Salvia officinalis; cis-thujone (38.05%), camphor (16.08%), 1,8-cineole (11.97%), trans-thujone (5.88%), camphene (4.79%), α -pinene (4.69%) and carvacrol (50.68%), γ-terpinene (34.44%) and α-terpinene (3.72%) in Satureja hortensis was determined. The highest EO contents (w/w %) was obtained in the plants of summer savory (2.05%), followed by the garden thyme (1.83%) and common sage (0.55%). It is necessary to identify the most effective compounds in order to extract or synthesise in pure form for future use in the pharmaceutical industry. Also, might be used for isolation of potentially active compounds from some of these medicinal plants in future and formulation of commercial therapeutic agents.

The effect of time and temperature on shelf life of essential oil composition of Teucrium polium L.

Teucrium polium has been used to treat gastrointestinal disorders, inflammation, diabetes and rheumatism. This plant has beneficial therapeutic properties. In this research the changes in the composition of essential oils from the aerial parts of Teucrium polium were determined at different temperatures and times. The essential oil of air-dried samples was obtained by hydro distillation and analyzed by gas chromatography/mass spectrometry (GC/MS). Changes in essential oils compositions were detected during storage for 3 months in refrigerator, freezer, and at room temperature. The results indicated that at room temperature, the proportions of the compounds with lower boiling temperatures such as Cis-Verbenol (2.11-1.78%) and Germacrene D (1.56-0.94%) were decreased significantly. Furthermore, the essential oil composition showed the least alterations and Teucrium polium L. kept its primary quality when stored at low temperatures, particularly in refrigerator and freezer (Except: α-Pinene, ß-Pinene and Limonene).

Biologia futura: the role of polyamine in plant science.

Polyamines (PAs) are positively charged amines such as putrescine, spermidine and spermine that ubiquitously exist in all organisms. They have been considered as a new type of plant biostimulants, with pivotal roles in many physiological processes. Polyamine levels are controlled by intricate regulatory feedback mechanisms. PAs are directly or indirectly regulated through interaction with signaling metabolites (H202, NO), aminobutyric acid (GABA), phytohormones (abscisic acid, gibberellins, ethylene, cytokinins, auxin, jasmonic acid and brassinosteroids) and nitrogen metabolism (maintaining the balance of C:N in plants). Exogenous applications of PAs enhance the stress resistance, flowering and fruit set, synthesis of bioactive compounds and extension of agricultural crops shelf life. Up-regulation of PAs biosynthesis by genetic manipulation can be a novel strategy to increase the productivity of agricultural crops. Recently, the role of PAs in symbiosis relationships between plants and beneficial microorganisms has been confirmed. PA metabolism has also been targeted to design new harmless fungicides.