Tracing the mass flow from glucose and phenylalanine to pinoresinol and its glycosides in phomopsis sp. Xp-8 using stable isotope assisted tof-ms

ABSTRACT _Phomopsis_ sp. XP-8, an endophytic fungus from the bark of Tu-Chung (_Eucommia ulmoides_ Oliv) showed capability to biosynthesize pinoresinol (Pin) and pinoresinol diglucoside

(PDG) from glucose (glu) and phenylalanine (Phe). To verify the mass flow in the biosynthesis pathway, [13C6]-labeled glu and [13C6]-labeled Phe were separately fed to the strain as sole

substrates and [13C6]-labeled products were detected by ultra-high-performance liquid chromatography-quadrupole time of flight mass spectrometry. As results, [13C6]-labeled Phe was

incorporated into [13C6]-cinnamylic acid (Ca) and _p_-coumaric acid (_p_-Co), and [13C12]-labeled Pin, which revealed that the Pin benzene ring came from Phe via the phenylpropane pathway.

[13C6]-Labeled Ca and _p_-Co, [13C12]-labeled Pin, [13C18]-labeled pinoresinol monoglucoside (PMG), and [13C18]-labeled PDG products were found when [13C6]-labeled glu was used,

demonstrating that the benzene ring and glucoside of PDG originated from glu. It was also determined that PMG was not the direct precursor of PDG in the biosynthetic pathway. The study

identified the occurrence of phenylalanine- lignan biosynthesis pathway in fungi at the level of mass flow. SIMILAR CONTENT BEING VIEWED BY OTHERS DEREPLICATION OF SECONDARY METABOLITES FROM

_SOPHORA FLAVESCENS_ USING AN LC–MS/MS-BASED MOLECULAR NETWORKING STRATEGY Article Open access 24 March 2025 DISCOVERY OF NOVEL NEUTRAL GLYCOSPHINGOLIPIDS IN CEREAL CROPS: RAPID PROFILING

USING REVERSED-PHASED HPLC–ESI–QQTOF WITH PARALLEL REACTION MONITORING Article Open access 19 December 2023 STABLE ISOTOPE AND CHEMICAL INHIBITION ANALYSES SUGGESTED THE EXISTENCE OF A

NON-MEVALONATE-LIKE PATHWAY IN THE YEAST _YARROWIA LIPOLYTICA_ Article Open access 10 March 2021 INTRODUCTION Pinoresinol diglucoside (PDG), (+)-1-pinoresinol 4, 4′-di-O-β-D-glucopyranoside,

is a major antihypertensive compound found in Tu-Chung, a traditional herb medicine with excellent efficacy for lowering blood pressure1. PDG also possesses the potential to prevent

osteoporosis2. Additionally, in the human intestine, PDG can be converted to enterolignans by intestinal microflora3, and enterolignans have potential to reduce the risk of breast cancer4

and other estrogen-dependent cancers5. PDG is found primarily in plants as lignans1,6 but yields are very low. _Phomopsis_ sp. XP-8 is an endophytic fungus isolated from the bark of Tu-Chung

that was previously found to produce PDG _in vitro_7, thus, providing an alternative resource to obtain PDG. This is the first report on the capability of a microorganism to synthesize

lignan. However, the PDG production by _Phomopsis_ sp. XP-8 was very low, which might be enhanced by regulatory controls based on the biosynthetic pathways. Therefore, it is essential to

identify the PDG biosynthetic pathway in this strain. The lignan biosynthetic pathway has only been reported in plants until now8,9. Synthesis of Pin in plants occurs via oxidative coupling

of monolignols, which are synthesized through the phenylpropanoid pathway with Phe, Ca, _p_-Co, _p_-coumaroyl-CoA, caffeate, ferulate, feruloy-CoA, coniferylaldehyde, and coniferyl alcohol

as intermediates or precursors10,11 (Fig. 1). PMG and PDG are converted from Pin by UDP-glucose-dependent glucosyltransferase8. However, the biosynthesis of PDG from Pin has not been

detected in plants and the Pin, PMG, and PDG biosynthetic pathways have not been elucidated in microorganisms. We previously reported that _Phomopsis_ sp. XP-8 converts mung bean starch and

polysaccharides to Pin, PMG, and PDG. Phe, cinnamic acid, and _p_-coumaric acid have been detected as products of the bioconversion12,13. Precursor feeding and enzymatic activity

measurements indicate that this strain synthesizes PDG via many steps, such as during mass flow of the phenylpropanoid pathway14. Genomic annotation indicates that the phenylpropane pathway

exists in this strain15 and some other microorganisms16. However, the functions of the denoted genes have not been verified until now. Therefore, it is necessary to verify the entire PDG

biosynthetic pathway in _Phomopsis_ sp. XP-8. Using stable or radioactive isotope-labeled compounds is an efficient and reliable strategy to verify the mass flow of unknown biosynthetic

pathways by tracing the isotope-labeled compounds from substrates to products17. 13C-labeled substrates have been used to shed light on the biodegradation pathways of organic pollutants18.

Isotope labeling combined with high-resolution mass spectrometry have also been used to track the abiotic transformation of pollutants in aqueous mixtures19. In recent years, liquid

chromatography-mass spectrometry (LC–MS) and ultra-high-performance liquid chromatography (UPLC) systems have been developed to facilitate the analysis of many substances at the same time

with high sensitivity and selectivity20. Stable isotope-labeled compounds have also been employed in several areas of biomedical research21. The combination of stable isotope-labeling

techniques with MS has allowed rapid acquisition and interpretation of data and has been used in many fields, including distribution, metabolism, food, and excretion studies22,23,24. The

biochemical pathway of the aromatic compounds in tea has been also been revealed using the stable isotope labeling method25. In this study, we applied stable isotopes labeling and MS to

trace the PDG biosynthetic pathway. Stable isotope-labeled 13C6 glu and 13C6 Phe were used as the substrates and ultra-high-performance liquid chromatography-quadrupole time of flight mass

spectrometry (UPLC-Q-TOF-MS/MS) was used to identify the products. MATERIALS AND METHODS MICROORGANISM AND CHEMICALS _Phomopsis_ sp. XP-8 previously isolated from the bark of Tu-Chung and

stored at the China Center for Type Culture Collection (Wuhan, China) (code: _Phomopsis_ sp. CCTCC M 209291) was used in this study. Phe (purity ≥98%, Sigma, St. Louis, MO, USA), Ca and

_p_-Co (purity ≥98%; Aladdin, Shanghai, China), PDG, PMG, and Pin (purity ≥99%; National Institutes for Food and Drug Control, Beijing, China) were used as the standards (dissolved in

methanol) for the structural analysis and product identification. [13C6]-Labeled Phe and glu were purchased from the Qingdao TrachinoidCo (≥99%; Qingdao, China). The purity of the

[13C6]-labeled Phe and glu was 99%. Methanol (HPLC grade) was purchased from Fisher Scientific (Fairlawn, NJ, USA). The water used in the experiment was purified using a Milli-Q water

purification system (18.5 M) (Millipore Corp., Bedford, MA, USA). Other reagents and chemicals were of analytical grade. PREPARATION OF _PHOMOPSIS_ SP. XP-8 CELLS _Phomopsis_ sp. XP-8 was

grown at 28 °C on potato dextrose agar plates for 5 days. Then, three pieces of mycelia (5 mm in diameter) were inoculated into 100 mL liquid potato dextrose broth in a 250-mL flask and

cultivated at 28 °C on a rotary shaker (180 rpm). After 4 days, the cells were collected by centrifugation at 4 °C (1,136 × g for10 min) using a centrifuge (HC-3018R, Anhui USTC Zonkia

Scientific Instruments Co., Ltd., Anhui, China). The cells were washed twice with sterile water and used for bioconversion according to the experimental design. BIOCONVERSION SYSTEMS The

bioconversion with unlabeled glu as the sole substrate was carried out in a 250-mL flask containing 100 mL of ultrapure water (pH 7), 5 g/L glu, and the prepared _Phomopsis_ sp. XP-8 cell

set a ratio of 10 g cells (wet weight) per 100 mL medium. To track the mass flow from glu to PDG, glu was changed to 5 g/L [13C6]-labeled glu in the above medium and the same conditions were

used for bioconversion. Bioconversion with Phe as the sole substrate was carried out in medium without glu, 7 mM [13C6]-labeled phenylalanine, and the prepared _Phomopsis_ sp. XP-8 cells at

a ratio of 10 g wet cells per 100 mL medium. All bioconversions were carried out for 48 h at 28 °C and 180 rpm. At the end of bioconversion, the broth was collected and filtered through an

intermediate speed qualitative filter paper before the products were detected. IDENTIFICATION OF THE ACCUMULATED PRODUCTS DURING BIOCONVERSION The products were extracted from the

vacuum-evaporated (0.09 MPa, 50 °C) bioconversion broth with methanol and adjusted to 4 mL for the UPLC measurements after filtration through a membrane (0.45 µm, 13 mm diameter; Millipore,

Billerica, MA, USA). The UPLC analysis was performed on a Waters Acquity UPLC system (Waters Corp., Milford, MA, USA), equipped with a binary pump, a thermostatically controlled column

compartment, and a UV detector. Gradient elution was performed on an Acquity UPLCTM BEH C18 column (50 mm × 2.1 mm I.D., 1.7 m; Waters) and the column temperature was maintained at 30 °C,

while sample temperature was 10 °C13. The MS analysis of the products was carried out on a Q-TOF PremierTM with an ESI source (Waters Corp.) at the optimized parameters of: capillary

voltage, 2.8 kV; sampling cone voltage, 20 V; extractor voltage, 4 V; source temperature, 100 °C; desolvation temperature, 250 °C, and flow rate of the desolvation gas (N2), 400 L/h. The

collision cell parameters for the Q-TOF-MS/MS analysis were: collision gas (Argon) flow rate, 0.45 L/h; collision energy, 15–35 eV. The mass spectra were recorded using full scan mode over a

mass range of _m/z_ 100–800 in negative ion mode. The MS acquisition rate was set to 1.0 s, with a 0.02 s interscan delay. The Q-TOF-MS/MS experiments were carried out by setting the

quadrupole to allow ions of interest to pass prior to fragmentation in the collision cell. Accurate mass measurements were obtained by means of a lock mass that introduces a low flow rate (3

 L/min) of a chrysophanol (253.0499) calibrating solution in the ESI-Q-TOF-MS and ESI-Q-TOF-MS/MS. All operations and acquisition and data analyses were controlled by Masslynx V4.1 software

(Waters Corp.). DATA PROCESSING Peak detection, alignment, and identification of the detected compounds were performed using Masslynx V4.1 software (Waters Corp.). The MS/MS fragmentation

patterns were used for informative non-targeted metabolic profiling of the LC-MS data, and the acquired LC-MS/MS spectrum was identified after comparison with spectra proposed by the Mass

bank database (www.massbank.jp), the KEGG database, and related reports. RESULTS DETECTION OF PRODUCTS CONVERTED FROM UNLABELED GLU Production of PDG, PMG, Pin, Phe, _p_-Co, and Ca were

detected in bioconversion systems using glu as the sole substrate. Data in Figs. 2–5 show the mass spectra of these compounds accumulated in the bioconversion systems and the corresponding

standards. Production of Phe was detected as _m/z_ = 164.08, and _m/z_ = 147.06 (Fig. 2A-4), which was consistent with the data obtained from the corresponding standards (Fig. 2A-2).

Similarly, production of PDG, PMG, Pin, _p_-Co, and Ca was also detected in the bioconversion system, indicating that glu was converted to these products by _Phomopsis_ sp. XP-8, as only glu

was provided in the bioconversion system. IDENTIFICATION OF PRODUCTS CONVERTED FROM [13C6]-LABELED PHE The phenylpropanoid pathway in plants starts with Phe and ends with _p-_Co. The same

mass flow was previously detected during PDG biofrom glu by _Phomopsis_ sp. XP-813. To verify this finding and the role of the Phe pathway in the biosynthesis of PDG, PMG, and Pin,

[13C6]-labeled Phe was used as the sole substrate in the bioconversion system without glu (mainly used as the glucoside donor). As results, 13C labeled Pin, Phe, _p_-Co, and Ca were

successfully detected (Fig. 6). The products were successfully detected at the same RT of their corresponding unlabeled standard substrates. All 13C-labeled product data and their

corresponding standard substrates are summarized in Table S1 (Supporting information). As shown in Fig. 6B, 13C-labeled Ca was detected as _m/z_ = 153.07, indicating that six 13C from

[13C6]-labeled Phe were incorporated into Ca. A daughter ion of 13C-labeled Ca was obtained at _m/z_ = 109.08, indicating six 13C referring to the standard Ca (_m/z_ = 103.06). The structure

of 13C-labeled Ca without -COO− was observed at _m/z_ = 109.08. Therefore, it was deduced that the six 13C were incorporated into the benzene ring of Ca not into –COO−. _P_-Co produced in

the conversion system was detected as _m/z_ = 169.05 and revealed six 13C by consulting the _p_-Co standard (Fig. 6C). A daughter ion of 13C-labeled _p_-Co was obtained at _m/z_ = 125.07,

indicating 6 Da mass shift than _p_-Co standard (_m/z_ = 119.06). The structure of 13C-labeled _p_-Co without –COO− (44 Da lost) was observed at _m/z_ = 125.07. Therefore, it was deduced

that the six 13C might be distributed in the benzene ring. 13C-labeled Pin was detected (Fig. 6D-1) and compared with the mass spectra of the Pin standard (C20H22O6, RT = 9.736 min, detected

as _m/z_ = 357.13 and _m/z_ = 151.04 respectively) (Table S2, Supporting information). 13C-labeled Pin was detected as _m/z_ = 369.05, indicating 12 Da mass shift than Pin standard (_m/z_ =

 357.13). A daughter ion of 13C-labeled Pin was observed at _m/z_ = 157.06, which showed a mass increase of 6 Da than Pin standard (_m/z_ = 151.04). The structure of 13C-labeled Pin with

loss of a benzene ring was identified as the major daughter ion of _m/z_ = 157.06 (Fig. 6D-1). This result confirmed that the six13C were distributed in a benzene ring, whereas the other

six13C might be in a symmetrical benzene ring. Therefore, we deduced that the Pin with 12 13C was bio-converted from the [13C6]-labeled Phe, Ca, or/and _p_-Co. This finding also confirmed

that the benzene ring in Pin came from Phe, which is consistent with that of the lignan biosynthetic pathway in plants. IDENTIFICATION OF PRODUCTS CONVERTED FROM [13C6]-LABELED GLUCOSE To

explore where Phe originated from the Pin biosynthetic pathway, [13C6]-labeled glu was supplied as the sole substrate in the bioconversion system with _Phomopsis_ sp. XP-8 cells. As results,

13C labeled PDG, PMG, Pin, Phe, _p_-Co, and Ca were detected (Figs. 7 and 8). The isotopic patterns observed in the MS and MS/MS spectra suggest the 13C from 13C6-labeled glu were

incorporated into the products of Phe (Fig. 7A), Ca (Fig. 7B) _p_-Co (Fig. 7C), PDG (Fig. 7D), PMG (Fig. 8A), Pin (Fig. 8B), respectively. The observed mass shifts, indicating the number of

incorporated 13C, were shown in the spectra. The detailed information on the products and possible positions of 13C in the products are summarized in Table S2 (Supporting information).

Interestingly, the analysis revealed that 13C6-labeled glu were incorporated into the core structure of PDG and PMG, and their glycosides. Additionally, the maximum of 16 13C was detected in

the formed Pin (C20H22O6), indicating the [13C6]-labeled glu partly contributed to the formation of Pin. The possible positions of 13C in the structures are summarized in Table S2

(Supporting information). Taken together, the mass flow from [13C6]- Phe to [13C6]-Ca, [13C6]-_p_-Co, and [13C12]-Pin was verified by the experiments using [13C6]-labeled Phe as the sole

substrate (Fig. 9A). The mass flow from [13C6]- glu to [13C]-Phe, [13C]-Ca, [13C]-_p_-Co, [13C]-Pin, [13C]-PMG, and[13C]-PDG was verified by the data obtained using [13C6]- glu as the sole

substrate (Fig. 9B). POSSIBLE PATHWAYS FOR BIOSYNTHESIS OF PDG AND PMG The evidences for the possible biosynthetic pathways of PDG, PMG, and Pin are summarized in Figs. 9 and 10. The pathway

from Phe to Pin, glu to Phe, Pin, PMG and PDG was verified (Fig. 9A,B, Supporting information Table S1 and Table S1). In addition, the bioconversion between PDG and PMG in _Phomopsis_ sp.

XP-8 was reported for the first time, and the analysis was showed in Fig. 10. As shown in Fig. 10, two structures of PMG were detected: one was [13C12]-PMG with two benzene rings converted

from 13C-labeled glu and an unlabeled glycoside (PMG _m/z_ 531.29), and the other was [13C18]-PMG with both benzene ring structures converted and a glucoside from 13C-labeled glu (PMG _m/z_

537.33). Similarly, two PDG structures were detected: one was [13C18]-PDG with a two benzene ring structure and one glycoside converted from 13C-labeled glu (PDG _m/z_ 699.27); the other one

was [13C24]- PDG with two benzene rings and two glycosides from 13C-labeled glu (PDG _m/z_ 705.26). If PMG was the direct precursor of PDG, PMG _m/z_ 531.29 would be converted to PDG _m/z_

699.27 by bonding one [13C6]-labeled glycoside through glycosylation; PMG _m/z_ 537.33 could also be converted to PDG _m/z_ 699.27 by bonding one unlabeled glycoside through glycosylation

and to PDG _m/z_ 705.26 by bonding one [13C6]-labeled glycoside. If this is true, PDG _m/z_ 699.27 would have two glucoside sources, whereas PDG _m/z_ 705.26 would have only one glucoside

source. Therefore, the concentration of PDG _m/z_ 705.26 should be lower than PDG _m/z_ 699.27. However, the data show that the relative abundance of PDG _m/z_ 705.26 was much higher than

that of PDG _m/z_ 699.27 (Fig. 7D-3). Therefore, PMG was not the precursor of PDG. In contrast, if PDG was the direct precursor of PMG, PDG _m/z_ 699.27 would be converted to PMG _m/z_

531.29 by hydrolyzation of one [13C6]-labeled glycoside and to PMG _m/z_ 537.33 by hydrolyzation of one unlabeled glycoside; PDG _m/z_ 705.26 would be converted to PMG _m/z_ 537.33 by

hydrolyzation of one [13C6]-labeled glycoside. If this is true, PMG _m/z_ 537.33 would have two glycoside sources, whereas PMG _m/z_ 531.29 would have only one source. The concentration of

PMG _m/z_ 531.29 should be lower than PMG _m/z_ 537.33. However, the data show that relative abundance of _m/z_ = 531.29 was higher than that of _m/z_ = 537.33 (Fig. 8A-3). Therefore, PDG

was not the precursor of PMG. DISCUSSION The 13C stable isotope labeling method was successfully used in this study to verify the phenylpropanoid-pinoresinol and biosynthetic pathway of its

glycosides in _Phomopsis_ sp. XP-8 during mass flow. This lignan biosynthetic pathway was only reported in plants until now8,9, so it was very significant to verify the occurrence of this

pathway in microorganisms. Stable Isotope-assisted metabolomics is an efficient way to trace and identify bio-transformed products and the metabolic pathways involved in their formation,

such as understanding the fate of organic pollutants in environmental samples17. It was the first time to use this method to verify the Phenylpropanoid-pinoresinol in a microorganism. In our

previous studies, many methods such as precursor feeding13, detection of enzyme activity14, and genomic annotation15 have been used to analyze the Phenylpropanoid-pinoresinol biosynthetic

pathway in _Phomopsis_ sp. XP-8. Through these studies, the precursors, enzymes activity and genes of PDG biosynthetic pathway have been found. The 13C stable isotope labeling method gave

further verification on the occurrence of lignan biosynthetic pathway in microorganisms by now. In addition to this, it is the first time that differences between the PDG and PMG

biosynthetic pathways have been verified. The results obtained in this study verify the existence of the phenylpropanoid-lignan metabolic pathway in _Phomopsis_ sp. XP-8. Genomic annotation

is an efficient way to discover the pathways that are normally difficult to reveal by metabolic and enzymatic evidence due to low intermediate accumulation, low end-product, and silent gene

expression under normal conditions. This method has been successfully used to identify the existence of a phenylpropanoid metabolic pathway in _Aspergillus oryzae_26, and the molecular

genetics of naringenin biosynthesis, a typical plant secondary metabolite in _Streptomyces clavuligerus_27, and the occurrence of the phenylpropanoid-lignan pathway in _Phomopsis_ sp.

XP-815. This study reports the existence of the phenylpropanoid-lignan pathway in _Phomopsis_ sp. XP-8 during mass flow and identified the metabolites. Additional studies should illustrate

the origin of the genes in the phenylpropanoid-lignan pathway of _Phomopsis_ sp. XP-8. Horizontal gene transfer (HGT) has long been recognized as an important force in the evolution of

organisms28. HGT occurs among different bacteria and plays important roles in the adaptation of microorganisms to different hosts or environmental conditions29. More and more evidence for

gene transfer between distantly related eukaryotic groups has been presented28.Therefore, we cannot exclude the possibility that XP-8 may have acquired the genes related to the lignan

biosynthetic pathway from its host plant by HGT during long-term symbiosis and evolution. However, further evidence is still needed to verify this proposed process. The results obtained in

this study provide useful information on the biosynthesis of lignans and their glycosides via microbial fermentation. Biosynthesis of lignans is of great interest to organic chemists as it

provides a model for biomimetic chemistry and has extensive applications30. Improvement has been made in the techniques to biosynthesize lignan products by regulating the lignan biosynthetic

pathway in trees through genetic modifications31. However, the lignan biosynthetic pathway has rarely been reported. More importantly, the bioconversion sequence from Pin to PDG and the

direct precursor of PDG have remained unclear until now. In previous studies on _Phomopsis_ sp. XP-8, the highest production of PDG and PMG did not occur simultaneously12 and PMG was not the

precursor of PDG because PDG production decreased and/or disappeared when PMG yield increased13. The present study demonstrated that PMG was not the precursor of PDG, and PDG was not the

precursor of PMG, indicating that Pin might be converted to PMG and PDG via two different pathways in _Phomopsis_ sp. XP-8, which has not been revealed in plants. Furthermore, this study

revealed that the bioconversion of Pin, PMG, and PDG from glu occurred simultaneously as that from Phe. We found that the benzene ring structure of Phe did not open throughout the entire Pin

bioconversion process in _Phomopsis_ sp. XP-8 when Phe was used as the sole substrate, indicating that the Pin benzene ring originated from Phe. Glu was converted to Phe and was the sole

glycoside donor for PDG biosynthesis. Therefore, glu not only participated in the formation of glycosides in PDG, but also provided the PDG benzene ring structure. This is different from

that found in plants, indicating there might be some other different pathways to produce these products in _Phomopsis_ sp. XP-8. Not all intermediates in the KEGG-identified plant-lignan

biosynthetic pathway related to Pin, PMG, and PDG formation were found in _Phomopsis_ sp. XP-8, such as caffeic acid, ferulic acid, and coniferyl alcohol (Fig. 1). This may be because the

pathways after _p_-Co are different in XP-8 from those in plants, or the accumulation of these intermediates was too low to be detected. Further studies are needed to verify this hypothesis.

In conclusion, the capability of _Phomopsis_ sp. XP-8 to biosynthesize Pin, PMG and PDG from [13C6]-Phe and [13C6]-glu was verified. The study illustrated the phenylpropanoid-pinoresinol

biosynthetic pathway in microorganism by using stable isotope assisted UPLC-Q-TOF-MS/MS, thus, demonstrating a completely new way to produce Pin, PMG and PDG by bioconversion process. In the

further studies, _Phomopsis_ sp. XP-8 could be used in producing these lignans and their derivatives by microbial fermentation or enzymatic reaction. In addition, the microbial fermentation

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Natural Science Foundation of China (grant no. 31471718), the Modern Agricultural Industry Technology System (CARS-30), the National Key Technology R&D Program (2015BAD16B02), the

National Natural Science Foundation of China (grant no. 31760446), and the Start-up funding of Shihezi University (RCSX201713), and Key research and development plan of Shaanxi Province

(2017ZDXL-NY-0304). AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, 127

Youyi West Road, Xi’an, Shaanxi Province, 710072, China Junling Shi, Xixi Zhao & Zhenhong Gao * College of Food, Shihezi University, Road Beisi, Shihezi, Xinjiang Province, 832003, China

Yan Zhang, Yongqing Ni & Zhixia Zhao * College of Enology, Northwest A & F University, Yangling, Shaanxi Province, 712100, China Yanlin Liu Authors * Yan Zhang View author

publications You can also search for this author inPubMed Google Scholar * Junling Shi View author publications You can also search for this author inPubMed Google Scholar * Yongqing Ni View

author publications You can also search for this author inPubMed Google Scholar * Yanlin Liu View author publications You can also search for this author inPubMed Google Scholar * Zhixia

Zhao View author publications You can also search for this author inPubMed Google Scholar * Xixi Zhao View author publications You can also search for this author inPubMed Google Scholar *

Zhenhong Gao View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS Y.Z. and J.L.S. designed and performed the cultivations, analysis of

metabolites and co-wrote the manuscript. Y.Q.N. and Y.L.L. performed the data analysis. Z.X.Z., X.X.Z. and Z.H.G. co-wrote the manuscript. CORRESPONDING AUTHOR Correspondence to Junling Shi.

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http://creativecommons.org/licenses/by/4.0/. Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Zhang, Y., Shi, J., Ni, Y. _et al._ Tracing the mass flow from glucose and

phenylalanine to pinoresinol and its glycosides in _Phomopsis_ sp. XP-8 using stable isotope assisted TOF-MS. _Sci Rep_ 9, 18495 (2019). https://doi.org/10.1038/s41598-019-54836-1 Download

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