Journal of Horticulture and Postharvest Research

Abstract Purpose: Due the importance of taxol and based on the confirmed role of certain endophytes of Yew tree in the production of this vital compound, the present study was designed to investigate the effect of isolated endophytic fungi on vegetative and qualitative characteristics of stevia plant. Research method: The experiment included five different endophytic fungi isolated from Yew tree. In order to do that, rooted cuttings of stevia were transferred to the pot after being inoculated with different isolated endophytic fungi (TB2, TB2-3, TB20, TB55) of Yew tree in four replications as a completely randomized design and were kept in outdoor conditions. To isolate endophytic fungi, root samples were collected from the yew trees in the Ziyarat forest located in Golestan province, Iran. Main findings: The results of the study revealed the positive effect of Yew tree endophytes as biotic agents on the growth and physiological parameters of stevia. Also, the fungal pathogenicity effect on stevia was not observed. In addition, the main stem diameter, internode spacing, leaf area and other measured parameters were affected by studied endophytes. Among of the five used isolates fungi, three were classified as stevia plant grows stimulator. Also, due to the highest total sugar and antioxidant activity of stevia, rest two isolates were classified as “bio-elicitor”. Limitations: There was no limitation to report. Originality/Value: The findings of the present study suggest that stevia, as a medicinal and economical herb, is capable of coexistence with yew endophytes. If taxol producer endophytes successfully transfer to stevia, it is possible to study the production of taxol in herbaceous plants, thereby opening the new door to easier and cheaper access to Taxol.

Abstract Purpose: The aim of this study was to formulate a new delivery system by the incorporation of Zataria multiflora. essential oil into solid lipid nanoparticles (SLN). Research Method: SLN formulations were prepared following the high-pressure homogenization after starring and ultra-trax homogneization techniques. In this experiment, three SLNs formulations were prepared using three types of lipids. Lipids included glycerol monostearate lipid, precirol and stearic acid lipid. The SLNs were characterized by Differential Scanning Calorimetery (DSC), Transmission Electron Microscopy (TEM) and particle size analysis. Findings: The results showed that particle size, polydispersity index and zeta potential of the above formulations were about 255, 220, 486 nm, 0.369, 0.251, 0.296,-37.8, -17.6 -27.2 mV respectively. The results obtained from transmission electron microscopy (TEM) revealed that in all 3 formulations, particle size less than 200 nm were spherical. Thermal analysis by DSC, confirmed the presence of solid particles in the prepared SLNs. Also, the essential oil encapsulation percentage of Formulations 1, 2 and 3 were 85.3, 91.3 and 95.2% respectively. Stability studies of particle size and zeta in four months revealed that SLNs containing essential oils had relatively good stability. Research limitations: Limitations of SLNs are: Lipid particle growth, Unpredictable gelation tendency. Originality/Value: Due to the chemical structures of essential oils, EOs can be easily degraded after exposure to humidity, heat, oxygen, light, owing to chemical and enzymatic reactions. To overcome the drawbacks of EOs, several researchers have suggested the encapsulation of these active ingredients into nanocarriers. The results of the present research revealed that SLNs composed of glycerin monostearate lipids, precirol and stearic acid, were good carriers for Z. multiflora essential oil.