Mohsen Eisapoor; Khodayar Hemmati; Nastaran Hemmati
Abstract
Introduction: Horsemint (Mentha longifolia L.) is a valuable medicinal and aromatic plant belonging to Lamiaceae family. It was reported that the contents and composition of perceived pharmacological properties varied significantly among populations. The genus Mentha L. (Lamiaceae), is widely distributed ...
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Introduction: Horsemint (Mentha longifolia L.) is a valuable medicinal and aromatic plant belonging to Lamiaceae family. It was reported that the contents and composition of perceived pharmacological properties varied significantly among populations. The genus Mentha L. (Lamiaceae), is widely distributed in all continents (except in South America and Antarctica). The systematic of the genus is not very elucidated because of the strong morphologic variations, levels of ploidy (2n = 2x = 24 to 2n = 6x = 96), and hybridizations intra- and interspecific (or between spontaneous and cultivated forms). M. longifolia or horsemint is a fast-growing and perennial herb which cultivated in all regions. The species possesses antimicrobial and antioxidant properties. The antimicrobial properties of the essential oils can be attributed to the presence of pulegone, menthone and neomenthone because they can destroy the structure of different polysaccharides, fatty acids and phospholipids by altering the permeability of the cell membrane and destroying the bacterial wall. The essential oils of horsemint are said to be cyclohexane and aromatic, and pulegone is the main compound of these oils has a definite aroma in the range of intense to spicy mint. The effects of environmental conditions on the plant growth and development, reproduction and distribution are well known in plant ecology. Many studies have been carried out about the relationships among plant chemical contents, biological activity and environmental variables in the natural and cultivated plant species. This information has been used to determine the medicinal value and economic importance of plant products.
Materials and Methods: In this research, the effects of six habitats with different altitudes (habitats of Amol city) on some morphological and biochemical characteristics of horsemint plants were investigated in a completely randomized design with three replications. This study was done to compare the amount of pulegone, total phenol, total flavonoids, antioxidant activity, chlorophyll a, chlorophyll b, total chlorophyll, carotenoid and also morphological features of horsemint such as number of leaves per plant, number of branches per plant, number of flowers and number of nodes. For antioxidant properties using DPPH method in 517 nm wavelength, total amount of phenol using Folin-Ciocalteu method in 765 nm wavelength and the total amount of flavonoid were done using the aluminum chloride method in 415 nm wavelength and they were measured by spectrophotometer. Essential oil was extracted from dried aerial parts using distillation by Clevenger apparatus for 3 hours. Gas chromatography (GC) was used to measure pulegone.
Results and Discussion: The results showed that the altitude and ecotype significantly affecting the growth and biochemical characteristics of horsemint plant. The highest number of leaves (25) and the shoots (27) of horsemint were obtained in the Gat Lash region with 2000 meters and Siozmin with 1850 meters above sea level, respectively. Gat Lash and Siozmin had the highest and lowest content of photosynthetic pigments, respectively. Although there was no significant difference between the content of phenol and flavonoids in different habitats, the highest rates were observed in the Pardemeh and Gat Lash habitats. The results showed that the highest and lowest oil were obtained from ecotypes of Gat Lesh with 2000 meters and Vash Verin with 2300 meters above sea level, respectively. As the height increased, the amount of pulegone was also increased in the leaves, so that the highest amount of pulegone was found in Pardemeh )6069 ppm) habitat by 2600 meters above sea level.
Conclusions: Generally, for obtaining the highest essential oil content and pulegone, the best ecotypes were Gat Lash and Pardemeh habitats, respectively. Due to the importance and usage of secondary metabolites in the human life, investigating the relationship between environmental conditions with the production and accumulation of secondary metabolites in plants can be very useful. Our results showed that the climatic conditions had a significant effect on the morphological characteristics of the horsemint, thereby increasing or decreasing the essential oil. In the present study, the best habitat for the highest pulegone was Pardemeh habitat but the habitat of Gat Lash could be a suitable habitat for domestication and cultivation of this plant because of its higher essential oil yield and relatively good pulegone content. For this purpose, it is recommended to study different habitats of this species in other parts of the country for finding the best ecotypes.
Nastaran Hemmati; Azim Ghasemnezhad; Javad Fattahi Moghadam; Pooneh Ebrahimi
Abstract
Introduction: all fruits that called citrus are from rutaceae family and aurantioideae subfamily. This subfamily have more than 33 different genus that only three of its genus (citrus, poncirus and fortunella) have economic aspects and in citrus producing country are important. It's reported that orange ...
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Introduction: all fruits that called citrus are from rutaceae family and aurantioideae subfamily. This subfamily have more than 33 different genus that only three of its genus (citrus, poncirus and fortunella) have economic aspects and in citrus producing country are important. It's reported that orange skin has a phenolic compounds which play a role in natural defense mechanism. Also various compounds of phenolic and antioxidant have a major role in fruit tolerance to stressful condition suh as cold and drought. Metabolites found in citrus fruits have antioxidant properties and it's very useful in pharmaceutical, food and cosmetics industries. Oranges, like other citrus fruits, are an excellent source of vitamin C; Vitamin C is a powerful natural antioxidant. Consumption of foods rich in vitamin C helps the body develop resistance against infectious agents and scavenge harmful, pro-inflammatory free radicals from the blood. Various factors such as rootstock type can effect on quality and quantity of citrus fruits. Also, the usage of rootstock causes the change in plant characteristics such as flowering time, ripening time, fruit quality and antioxidant characters of the fruits. Other factors except the rootstock such as scion, geographical and climate factors are effective on producing secondary metabolites. Also active substances or secondary metabolites are producing by the conduction of genetic processes, but their production are being effected by other factors obviously. The aim of this study is to investigating the biochemical changes grafted tree fruit that affected by rootstock with study the correlation between grafted tree and rootstock changes.
Materials and Methods: This study was done to compare the amount of total phenol, total flavonoids and antioxidant features of fruit flesh and skin with investigating the effect of cultivar and rootstock on these parameters based on completely randomized factorial design with three replications. For this purpose total phenol, total flavonoid and antioxidant activity in two citrus cultivar (morro and mars) that grafted on four rootstock (yuzu, citrumelo, sour orange and shel mahalleh) with seedling rootstocks fruit were studied in fruit skin and flesh. Fruits were harvested in the middle of December according to their total soluble solid materials (TSS) which was 10 and then transferred to the researching laboratory in Gorgan Agricultural Science and Natural Resources University. Antioxidant properties using DPPH method in 517 nm wavelength, total amount of phenol using folin siocalteu method in 765 nm wavelength and the total amount of flavonoid were done using the aluminum chloride method in 415 nm wavelength and they were measured using spectrophotometer.
Results and Discussion: the result showed that the two factors consisting rootstock and scion have significant effect on the amount of total phenol, total flavonoid and antioxidant properties of extracts of citrus skin and flesh. The greatest amount of phenolic compounds was produced in the skin of morro cultivar that grafted on shel mahalleh rootstock and the lowest amount was observed in the flesh of yuzu seedling rootstock. Total flavonoid was affected by fruit tissue, cultivar and rootstock. The maximum amount of that was seen in the skin of morro and mars cultivar that was grafted on yuzu rootstock and the minimum amount was recorded in the flesh of morro cultivar that grafted on sour orange rootstock. Also the highest antioxidant activity was produced in skin of citrumelo seedling rootstock and the lowest amount was seen in flesh of yuzu seedling rootstock. The investigation on citrus rootstock showed that, antioxidant activity, total phenol and total flavonoid had significant effect in different rootstock and cultivar fruit. These compounds were affected by climatic condition. Because the light is effective in biosynthesis of phenolic compounds, in fact, these substances have a protective role against the light, especially short wavelengths. Therefore their more accumulation is in skin. The results of this experiment and also the results of the other researcher show that the rootstock effect is related to the quality of grafted species with the species, rootstock type and their interaction.
Conclusion: Based on these experiments, there was significant difference between antioxidant compounds of grafted tree fruit with rootstock fruit but there wasn’t a clear relationship between them. It seems this difference was due to combination and physiological characteristic of each fruit. It seems that the accumulation of chemicals in citrus fruit superior than every factors depends on genetic characteristics and inherent abilities. So that some factors specially rootstock has an important and determinant role in accumulation of these substances.
