Paclitaxel is a medicinal ingredient with high anticancer activity and widely used in hospitals and clinics. In this study, we isolate endophytic fungi efficiently producing paclitaxel from yew for the purpose of paclitaxel manufacture.The bark of Taxus wallichiana var. mairei was surface sterilized and then inoculated in potato dextrose agar culture medium to isolate endophytic fungi. The paclitaxel in the fungal culture was extracted with mixture of chloroform and the same amount of methanol. The content of paclitaxel in the extract was determined and identified with LC-MS. The endophytic fungus efficiently producing paclitaxel was species identified with ITS rDNA and 26S D1/D2 rDNA sequencing.There were 528 endophytic fungal strains were isolated from the bark of T wallichiana var. mairei in total. There was only a strain efficiently producing paclitaxel in these endophytic fungi. The unique strain was identified as Phoma medicaginis. The paclitaxel contents in whole potato dextrose broth (PDB) culture, spent culture medium from this strain and that in dry mycelium is 1.215 mg/L, 0.936 mg/L, and 20 mg/kg, respectively.An endophytic fungus efficiently producing paclitaxel was isolated from T wallichiana var. mairei. This isolated endophytic fungus can be used as a producing strain for paclitaxel manufacture.

Endophytic fungi of inner root bark of Taxus wallichiana var. mairei were investigated in order to find endophytes producing 10-DABIII (10-deacetyl baccatin III). Purified colonies were cultured in potato dextrose broth (PDB), and then the organic extracts from fungi were analyzed with HPLC, LC-MS, and (1)H NMR. Of 102 fungal endophytes isolated from the inner root bark, only one strain named IRB54 can yield 10-DABIII but no taxol and baccatin III. In PDB culture medium, its productivity was 187.564 ug/l. Based on its morphological characteristics and molecular data, the IRB54 strain was identified as Trichoderma sp. The isolation of the fungus IRB54 yielding 10-DABIII will provide an alternative resource to manufacture taxol/taxotere via semi-synthesis and some useful clues for improving the understanding of taxane synthesis evolution.

Oridonin is a diterpenoid with anti-cancer activity that occurs in the Chinese medicinal plant Isodon rubescens and some related species. While the bioactivity of oridonin has been well studied, the extent of natural variation in the production of this compound is poorly known. This study characterizes natural variation in oridonin production in order to guide selection of populations of Isodon with highest oridonin yield. Different populations of I. rubescens and related species were collected in China, and their offspring were grown in a greenhouse. Samples were examined for oridonin content, genotyped using 11 microsatellites, and representatives were sequenced for three phylogenetic markers (ITS, rps16, trnL-trnF). Oridonin production was mapped on a molecular phylogeny of the genus Isodon using samples from each population as well as previously published Genbank sequences. Oridonin has been reported in 12 out of 74 species of Isodon examined for diterpenoids, and the phylogeny indicates that oridonin production has arisen at least three times in the genus. Oridonin production was surprisingly consistent between wild-collected parents and greenhouse-grown offspring, despite evidence of gene flow between oridonin-producing and non-producing populations of Isodon. Additionally, microsatellite genetic distance between individuals was significantly correlated with chemical distance in both parents and offspring. Neither heritability nor correlation with genetic distance were significant when the comparison was restricted to only populations of I. rubescens, but this result should be corroborated using additional samples. Based on these results, future screening of Isodon populations for oridonin yield should initially prioritize a broad survey of all species known to produce oridonin, rather than focusing on multiple populations of one species, such as I. rubescens. Of the samples examined here, I. rubescens or I. japonicus from Henan province would provide the best source of oridonin.

The objective of this study was to isolate endophytic fungi producing baccatin III from yew for the purpose of baccatin III and paclitaxel manufacture. Surface sterilized bark of Taxus wallichiana var. mairei was used as source material with potato dextrose agar culture medium for isolation of endophytic fungi. Fungal cultures were extracted with a mixture of chloroform/methanol (1:1, v/v) and the baccatin III in the extracts was determined and authenticated with LC-MS. An endophytic fungus that produced baccatin III was identified by ITS rDNA and 26S D1/D2 rDNA sequencing. A total of 192 endophytic fungal strains were isolated from T. wallichiana var. mairei. Only one of the 192 strains produced baccatin III and it was identified as Diaporthe phaseolorum. The productivity of this strain cultured in PDA culture medium was 0.219 mg/l. The isolated endophytic fungus produced baccatin III at a relatively high level and shows promise as a producing strain for baccatin III and paclitaxel manufacture after strain improvement.

photosynthetic and chlorophyll fluorescence characteristics of Isodon rubescens (Hemsley) H. Hara Jian Zaiyou ✉ , Zhou Xiuren & tian Jing the ecological and economic cultivation of Isodon rubescens is currently being carried out. the demand of I. rubescens for light intensity should be made clear to estimate whether the environmental conditions of an area are suitable for cultivating I. Rubescens and improve cultivation techniques. the photosynthetic and chlorophyll fluorescence characteristics of I. rubescens were determined with a Li-6400 photosynthesis system and PAM-2500 portable chlorophyll fluorescence apparatus. The results showed that there was no obvious midday depression of photosynthesis in I. rubescens leaves. the light compensation point and light saturation point of I. rubescens leaves were 21.83482 µmol•m −2 •s −1 and 802.262 µmol•m −2 •s −1 , respectively. the co 2 compensation point and co 2 saturation point of I. rubescens leaves were 101.7199 µmol•mol −1 and 1674.514 µmol•mol −1 , respectively. the maximal photochemical efficiency of photosystem II ((Fm-Fo)/Fm) in I. rubescens leaves reached 0.7. The electron transport rate of photosystem ii in I. rubescens leaves reached 20 μmol electrons/(m 2 •s). I. rubescens can tolerate intense light above the light compensation point and utilize low light. I. rubescens leaves have a strong photoprotective capacity. I. rubescens can grow in both sunny and shady places. the most important factor affecting photosynthetic efficiency in I. rubescens leaves is the concentration of co 2 in air. Isodon rubescens (Hemsley) H. Hara is a perennial subshrub belonging to a genus of the Lamiaceae family 1. There are several bioactive chemical components in I. rubescens, such as oridonin and ponicidin. The dry aerial portions of I. rubescens are named rabdosiae rubescentis herba and are used in traditional Chinese medicine for the treatment of sore throats, inflammation and gastrointestinal problems 2,3. The ecological and economic cultivation of I. rubescens is currently being carried out. However, there are different environmental conditions in different places. Wild I. rubescens grows on mountains or hills. There are obvious differences between the environmental conditions of mountains and plains. The demand of I. rubescens for light intensity should be made clear. The photosynthetic and chlorophyll fluorescence characteristics of I. rubescens were studied in this research to define the most suitable environmental conditions for I. rubescens cultivation and improve cultivation techniques. Results Diurnal variation in I. rubescens leaf photosynthesis. The results of the diurnal variation in I. rubescens leaf photosynthesis are shown in Table 1. Based on the collected data, the curve of the diurnal variation in I. rubescens leaf photosynthesis is shown in Fig. 1. The diurnal variation in I. rubescens leaf photosynthesis indicates that there was no obvious midday depression of photosynthesis. There is still a high net photosynthetic rate in I. rubescens leaves at noon w...