Medicinal Plants
M. Yadegari
Abstract
Introduction
Satureja bachtiarica is one of the important endemic species and is used in medicinal and food industries. This plant is rich in essential oil, flavonoids, monoterpene glycosides and trypanocidal terpenoids. The main compounds of the essential oil from S.bachtiarica L. collected from natural ...
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Introduction
Satureja bachtiarica is one of the important endemic species and is used in medicinal and food industries. This plant is rich in essential oil, flavonoids, monoterpene glycosides and trypanocidal terpenoids. The main compounds of the essential oil from S.bachtiarica L. collected from natural habitats are alpha-pinene, p-cymene, carvacrol and gamma-terpinene. The environmental factors cause changes in the growth, quantity, and quality of active substances (such as alkaloids, glycosides, steroids and volatile oils) in medicinal and aromatic plants. Among environmental stresses, water deficit plays an important role in the biosynthesis of secondary metabolites in medicinal and aromatic plants in arid and semi-arid regions like Iran. Drought stress has detrimental effects on growth and yield and can upset the balance between the antioxidant defense system and free radicals by stimulating a series of biochemical reactions, where free radicals cause cell damage. In sustainable production systems of medicinal and aromatic plants, stable quantitative and qualitative functions can be achieved under conditions of environmental stress and it is possible to improve the production of secondary metabolites in these plants under adverse environmental conditions. Therefore, this study was done to evaluate the amino acids on the physiological and phytochemical properties of S. bachtiarica to determine and introduce the best amino acids under water stress.
Materials and Methods
This investigation was done from spring (May) 2022 to fall (September) 2023 at the Research Farm of Islamic Azad University, Branch of Shahrekord (latitude. 32°20′ N, longitude. 50°51′ E, altitude. 2061 m). Based on the Köppen climate classification, the climate of the study area is classified as cold and semiarid. This study was conducted in a randomized complete block design (RCBD) as a split plot layout with three replications. Irrigation regimes (3-day, 6-day, and 9-day intervals) were assigned as the main plots, while the foliar application of amino acids (methionine, lysine, phenylalanine, and proline) was designated as the subplots. In each year, treatments were applied at 3 stages (3 months after sowing, end of vegetation, before flowering, beginning of flowering and early flowering) and harvesting was done in the complete flowering stage. Weed control was applied manually during the entire experiment. During the experiment, no fertilizer and no systemic pesticide and herbicide were used. The harvested shoots were transferred to the laboratory for extracting and analysis of the leaves and stems of treated plants. For assessment of the total chlorophyll content of S. bachtiarica, the leaves were extracted with 80% acetone. The absorbance of the extraction was read at 470, 648, and 664 nm, and the content of total chlorophyll was calculated as mg per g leaf dry weight. Total phenol content was measured by the Folin-Ciocalteu reagent as reported by Singleton and Rossi. The total phenol content was expressed as mg of gallic acid equivalent per g leaf dry weight according to standard curves of gallic acid. The essential oils were extracted by hydro-distillation and analyzed using GC/MS.
Results and Discussion
Applied amino acids significantly influenced the morpho-physiological and phytochemical characters of Satureja bachtiarica. In two years, the highest chlorophyll content (1.41-1.54 mg.g-1 FW) and total phenol content (2.45-2.72 mg.g-1 FW) were obtained in methionine (2.5 g.l-1) and phenylalanine (100 µM) treatments by irrigation regimes 3-day interval. The highest essential oil contents (1.09-1.61 %) were obtained from the plants treated by methionine (2.5 g.l-1) and phenylalanine (100 µM) treatments by irrigation regime 3 days interval. The main chemical compounds of essential oil were P-cymene (17.12-19.45 %), gamma-terpinene (18.14-16.87 %) and Carvacrol (45.12-51.24 %) belonging to cyclic monoterpenes. The treatments had significant effectiveness on cyclic monoterpens such as alpha-terpinene, gamma-terpinene, germacren-d, carvacrol, thymol and p-cymene. Increasing of essential oil content/composition by use of amino acids was seen. The main components of essential oil in plants treated by proline were lesser than other treated plants. In two years of this research amino acids of methionine and phenylalanine mad the most amounts of carvacrol and essential oil content. The monoterpene alcohols in volatile oils of the treated plants with amino acids elicitors considerably were higher than the sesquiterpenes. According to the ratio of monoterpenes alcohol to sesquiterpenes in volatile oils of the treated S. bachtiarica with different elicitors, the foliar application of amino acids can improve the odor quality of S. bachtiarica volatile oil.
Conclusions
Foliar application of methionine (2.5 g.l-1) and phenylalanine (100 µM) treatments better than other treatments increased the morpho-physiological and essential oil attributes. Environmental conditions such as drought play a key role in plant growth and biosynthesis of different metabolic compounds. The observed variation in shoot yield and phytochemical content of S. bachtiarica during the studied years may related to differences in photoperiod, temperature, solar radiation, precipitation and occurrence of biotic and abiotic stresses at different growing seasons. Also amino acids had very important effectiveness on content/composition of essential oil of S. bachtiarica. Generally, treats of methionine and phenylalanine can be a good strategy to improve morpho-physiological characteristics and essential oil quantity and quality of S. bachtiarica in the same climate.
Medicinal Plants
M. Yadegari
Abstract
Introduction
Hyssopus officinalis L. belongs to the family Lamiaceae, and is one of the endangered endemic species in Iran. This plant is rich in essential oil, flavonoids, monoterpene glycosides, trypanocidal terpenoids, rosmarinic acid, and linolenic acid6. The main compounds of the essential oil ...
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Introduction
Hyssopus officinalis L. belongs to the family Lamiaceae, and is one of the endangered endemic species in Iran. This plant is rich in essential oil, flavonoids, monoterpene glycosides, trypanocidal terpenoids, rosmarinic acid, and linolenic acid6. The main compounds of the essential oil from H. officinalis L. collected from natural habitats are α-pinene, Sabinene, 3-Carene, Beta-Pinene, Cis- Pinocamphone, Myrtenol, Pinocamphone and Camphor. The environmental factors cause changes in the growth, quantity, and quality of active substances (such as alkaloids, glycosides, steroids and volatile oils) in the medicinal and aromatic plants. Among environmental stresses, water deficit stress plays an important role in the biosynthesis of secondary metabolites in medicinal and aromatic plants in arid and semi-arid regions like Iran. Drought stress has detrimental effects on growth and yield and can upset the balance between the antioxidant defense system and free radicals by stimulating a series of biochemical reactions, where free radicals cause cell damage. In sustainable production systems of medicinal and aromatic plants, stable quantitative and qualitative functions can be achieved under conditions of environmental stress and it is possible to improve the production of secondary metabolites in these plants under adverse environmental conditions. Therefore, this study was done to evaluate the organic elicitors on the physiological and phytochemical properties of H.officinalis to determine and introduce the best elicitor under water stress.
Materials and Methods
This investigation was done from spring (May) 2022 to fall (September) 2023 at the Research Farm (latitude. 32°20′ N, longitude. 50°51′ E, altitude. 2061 m). Based on the Köppen climate classification, the climate of the area of study is classified as cold and semiarid. The present study was conducted in a randomized complete block design (RCBD) with three replications to investigate the effect of foliar application of different organic elicitors (chitosan, salicylic acid and phenylalanine) with control level (without any spraying) on the physiological and phytochemical characters of H. officinalis L. In each year, treatments were performed in 3 stages (end of vegetative, beginning of flowering and 50% of flowering) and in full flowering, harvesting was done. 3 irrigation regimes (4, 6, 8 day interval) in main plots and foliar application of elicitors in sub plots were done. The essential oils were extracted by hydro-distillation and analyzed using GC/MS.
Results and Discussion
According to obtained results, applied organic elicitors significantly influenced the physiological and phytochemical characters of H. officinalis L. However the assayed traits showed slightly variation during the studied years. In two years, the highest chlorophyll content (17.12-17.31 mg.Kg-1 FW) and total phenol content (1.77-1.81 mg.g-1 DW) were obtained in chitosan (0.5 mg.l-1) and phenyl alanine (1000 mg.l-1) treatments respectively. In most of measured characters, plants treated with chitosan (0.5 mg.l-1) and phenyl alanine (1000 mg.l-1) were in the same group. Amounts of some characters in plants treated with phenyl alanine (2000 mg.l-1) and salicylic acid (3 mM) lesser than control plants. The main constituents of essential oil were Sabinene, 3-Carene, Beta-Pinene, Cis- Pinocamphone, Myrtenol, Pinocamphone and Camphor (cyclic monoterpenes) that made the most components of essential oil plants. Among of elicitors, the chitosan effect on increasing of physiological and phytochemical characters such as the chlorophyll content was higher than other elicitors. Applied elicitors showed significant effects on essential oil content and composition of H. officinalis L. The highest essential oil content (0.89-0.91 %) was obtained from the treated plants by chitosan (0.5 mg.l-1). According to the biennial results of the chemical analysis of the essential oils from plants treated with treatments by GC/MS, the most important chemical compounds that determine the quality of H. officinalis L. essential oil including Beta-Pinene (17.93-18.53 %), Pinocamphone (24.97-25.12 %) and Cis-Pinocamphone (42.87-45.12 %) were identified. Cis-Pinocamphone belonging to bicyclic monoterpene was the predominant constituent of essential oil of H. officinalis L.
Conclusion
According to the results of this study, water deficit stress caused significant phytochemical changes in the H. officinalis L. essential oil. The main constituents of the volatile oils of H. officinalis L. were Sabinene, 3-Carene, Beta-Pinene, Cis- Pinocamphone, Myrtenol, Pinocamphone and Camphor were identified in the H. officinalis essential oil. Generally, Foliar application of chitosan and phenyl alanine significantly increased the monoterpenes compounds in essential oils of Hyssopus officinalis L., so that the content of these compounds and essential oil content in treated plants by organic elicitors 63% was more than the control plants. Finally, the application of chitosan at 0.5 mg.l-1 can be a good strategy to improve physiological and essential oil quantity and quality of H. officinalis L. in cold and semi-arid climates.
