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Статті в журналах з теми "GlucoCEST"

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Автор: Grafiati

Опубліковано: 7 липня 2024

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1

Jin, Tao, Hunter Mehrens, Kristy S. Hendrich, and Seong-Gi Kim. "Mapping Brain Glucose Uptake with Chemical Exchange-Sensitive Spin-Lock Magnetic Resonance Imaging." Journal of Cerebral Blood Flow & Metabolism 34, no. 8 (May 28, 2014): 1402–10. http://dx.doi.org/10.1038/jcbfm.2014.97.

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Uptake of administered D-glucose (Glc) or 2-deoxy-D-glucose (2DG) has been indirectly mapped through the chemical exchange (CE) between glucose hydroxyl and water protons using CE-dependent saturation transfer (glucoCEST) magnetic resonance imaging (MRI). We propose an alternative technique—on-resonance CE-sensitive spin-lock (CESL) MRI—to enhance responses to glucose changes. Phantom data and simulations suggest higher sensitivity for this ‘glucoCESL’ technique (versus glucoCEST) in the intermediate CE regime relevant to glucose. Simulations of CESL signals also show insensitivity to B0-fluctuations. Several findings are apparent from in vivo glucoCESL studies of rat brain at 9.4 Tesla with intravenous injections. First, dose-dependent responses are nearly linearly for 0.25-, 0.5-, and 1-g/kg Glc administration (obtained with 12-second temporal resolution), with changes robustly detected for all doses. Second, responses at a matched dose of 1 g/kg are much larger and persist for a longer duration for 2DG versus Glc administration, and are minimal for mannitol as an osmolality control. And third, with similar increases in steady-state blood glucose levels, glucoCESL responses are ~2.2 times higher for 2DG versus Glc, consistent with their different metabolic properties. Overall, we show that glucoCESL MRI could be a highly sensitive and quantifiable tool for glucose transport and metabolism studies.

2

Bender, Benjamin, Kai Herz, Anagha Deshmane, Vivien Richter, Ghazaleh Tabatabai, Jens Schittenhelm, Marco Skardelly, et al. "GLINT: GlucoCEST in neoplastic tumors at 3 T—clinical results of GlucoCEST in gliomas." Magnetic Resonance Materials in Physics, Biology and Medicine 35, no. 1 (December 10, 2021): 77–85. http://dx.doi.org/10.1007/s10334-021-00982-5.

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Abstract Objective Clinical relevance of dynamic glucose enhanced (DGE) chemical exchange saturation transfer (CEST) imaging has mostly been demonstrated at ultra-high field (UHF) due to low effect size. Results of a cohort study at clinical field strength are shown herein. Materials and methods Motion and field inhomogeneity corrected T1ρ‐based DGE (DGE⍴) images were acquired before, during and after a d-glucose injection with 6.3 s temporal resolution to detect accumulation in the brain. Six glioma patients with clear blood–brain barrier (BBB) leakage, two glioma patients with suspected BBB leakage, and three glioma patients without BBB leakage were scanned at 3 T. Results In high-grade gliomas with BBB leakage, d-glucose uptake could be detected in the gadolinium (Gd) enhancing region as well as in the tumor necrosis with a maximum increase of ∆DGE⍴ around 0.25%, whereas unaffected white matter did not show any significant DGE⍴ increase. Glioma patients without Gd enhancement showed no detectable DGE⍴ effect within the tumor. Conclusion First application of DGE⍴ in a patient cohort shows an association between BBB leakage and DGE signal irrespective of the tumor grade. This indicates that glucoCEST corresponds more to the disruptions of BBB with Gd uptake than to the molecular tumor profile or tumor grading.

3

Kim, Mina, Afroditi Eleftheriou, Luca Ravotto, Bruno Weber, Michal Rivlin, Gil Navon, Martina Capozza, et al. "What do we know about dynamic glucose-enhanced (DGE) MRI and how close is it to the clinics? Horizon 2020 GLINT consortium report." Magnetic Resonance Materials in Physics, Biology and Medicine 35, no. 1 (January 15, 2022): 87–104. http://dx.doi.org/10.1007/s10334-021-00994-1.

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AbstractCancer is one of the most devastating diseases that the world is currently facing, accounting for 10 million deaths in 2020 (WHO). In the last two decades, advanced medical imaging has played an ever more important role in the early detection of the disease, as it increases the chances of survival and the potential for full recovery. To date, dynamic glucose-enhanced (DGE) MRI using glucose-based chemical exchange saturation transfer (glucoCEST) has demonstrated the sensitivity to detect both d-glucose and glucose analogs, such as 3-oxy-methyl-d-glucose (3OMG) uptake in tumors. As one of the recent international efforts aiming at pushing the boundaries of translation of the DGE MRI technique into clinical practice, a multidisciplinary team of eight partners came together to form the “glucoCEST Imaging of Neoplastic Tumors (GLINT)” consortium, funded by the Horizon 2020 European Commission. This paper summarizes the progress made to date both by these groups and others in increasing our knowledge of the underlying mechanisms related to this technique as well as translating it into clinical practice.

4

Kim, Mina, Francisco Torrealdea, Sola Adeleke, Marilena Rega, Vincent Evans, Teresita Beeston, Katerina Soteriou, et al. "Challenges in glucoCEST MR body imaging at 3 Tesla." Quantitative Imaging in Medicine and Surgery 9, no. 10 (October 2019): 1628–40. http://dx.doi.org/10.21037/qims.2019.10.05.

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5

Nasrallah, Fatima A., Guilhem Pagès, Philip W. Kuchel, Xavier Golay, and Kai-Hsiang Chuang. "Imaging Brain Deoxyglucose Uptake and Metabolism by Glucocest MRI." Journal of Cerebral Blood Flow & Metabolism 33, no. 8 (May 15, 2013): 1270–78. http://dx.doi.org/10.1038/jcbfm.2013.79.

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2-Deoxy-D-glucose (2DG) is a known surrogate molecule that is useful for inferring glucose uptake and metabolism. Although 13C-labeled 2DG can be detected by nuclear magnetic resonance (NMR), its low sensitivity for detection prohibits imaging to be performed. Using chemical exchange saturation transfer (CEST) as a signal-amplification mechanism, 2DG and the phosphorylated 2DG-6-phosphate (2DG6P) can be indirectly detected in 1H magnetic resonance imaging (MRI). We showed that the CEST signal changed with 2DG concentration, and was reduced by suppressing cerebral metabolism with increased general anesthetic. The signal changes were not affected by cerebral or plasma pH, and were not correlated with altered cerebral blood flow as demonstrated by hypercapnia; neither were they related to the extracellular glucose amounts as compared with injection of D- and L-glucose. In vivo31P NMR revealed similar changes in 2DG6P concentration, suggesting that the CEST signal reflected the rate of glucose assimilation. This method provides a new way to use widely available MRI techniques to image deoxyglucose/glucose uptake and metabolism in vivo without the need for isotopic labeling of the molecules.

6

Kentrup, Dominik, Annika Busch, Helga Pawelski, Eberhard Schlatter, Verena Hoerr, and Stefan Reuter. "SP772NON-INVASIVE DETECTION OF ACUTE RENAL ALLOGRAFT REJECTION THROUGH GLUCOCEST MRI." Nephrology Dialysis Transplantation 30, suppl_3 (May 2015): iii632. http://dx.doi.org/10.1093/ndt/gfv201.05.

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7

Colgan, Niall, Matthew Donoghue, Zdzislaw Zuchora, Brendan Tuohy, and Wil van der Putten. "Investigation of GlucoCEST as novel clinical MR biomarker of glucose metabolism." Physica Medica 32, no. 7 (July 2016): 959. http://dx.doi.org/10.1016/j.ejmp.2016.05.048.

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8

Xu, Xiang, Jiadi Xu, Kannie W. Y. Chan, Jing Liu, Huanling Liu, Yuguo Li, Lin Chen, Guanshu Liu, and Peter C. M. van Zijl. "GlucoCEST imaging with on-resonance variable delay multiple pulse (onVDMP) MRI." Magnetic Resonance in Medicine 81, no. 1 (July 29, 2018): 47–56. http://dx.doi.org/10.1002/mrm.27364.

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9

Kentrup, Dominik, Philipp Bovenkamp, Annika Busch, Katharina Schuette-Nuetgen, Helga Pawelski, Hermann Pavenstädt, Eberhard Schlatter, et al. "GlucoCEST magnetic resonance imaging in vivo may be diagnostic of acute renal allograft rejection." Kidney International 92, no. 3 (September 2017): 757–64. http://dx.doi.org/10.1016/j.kint.2017.04.015.

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10

Xu, Xiang, Jiadi Xu, Linda Knutsson, Jing Liu, Huanling Liu, Yuguo Li, Bachchu Lal, et al. "The effect of the mTOR inhibitor rapamycin on glucoCEST signal in a preclinical model of glioblastoma." Magnetic Resonance in Medicine 81, no. 6 (February 22, 2019): 3798–807. http://dx.doi.org/10.1002/mrm.27683.

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11

Xu, Xiang, Akansha Ashvani Sehgal, Nirbhay N. Yadav, John Laterra, Lindsay Blair, Jaishri Blakeley, Anina Seidemo, et al. "d ‐glucose weighted chemical exchange saturation transfer (glucoCEST)‐based dynamic glucose enhanced (DGE) MRI at 3T: early experience in healthy volunteers and brain tumor patients." Magnetic Resonance in Medicine 84, no. 1 (December 24, 2019): 247–62. http://dx.doi.org/10.1002/mrm.28124.

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12

Pudrith, Charles, Timothy T. K. Jung, You Hyun Kim, Dusan Martin, Michael Wall, Jared Inman, and Rachelle Wareham. "SP338 – Treatment of LPS-induced otitis media with various glucocort." Otolaryngology - Head and Neck Surgery 141, no. 3 (September 2009): P199. http://dx.doi.org/10.1016/j.otohns.2009.06.638.

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13

Mulyanti, Budi, Lilik Hasanah, Tommi Hariyadi, Rischa Novitasari, Arjuni B. Pantjawati, Heru Yuwono, and Khairurrijal. "The Influence of Glucose Concentration to Resonant Wavelength Shift of Polymer-Based Microring Resonators." Advanced Materials Research 1112 (July 2015): 32–36. http://dx.doi.org/10.4028/www.scientific.net/amr.1112.32.

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Microring resonators (MRRs) is a compact and multi-functioned device which is mainly characterized by free spectral range (FSR) and quality factor (Q-factor). In this paper, the influence of glucose concentration to the resonant wavelength shift of MRRs is presented. The calculation was carried out using semi-numerical method for different values of FSR and Q-factor. The parameters used in the calculation including incident wavelength, ring radii of circular waveguide, gap sizes between circular and straight waveguides, the dimension of both waveguides, and refractive index of polymer, SiO2 and glucoce solution. The results show that glucose affects the resonant wavelength shift for each values of FSR and Q-factor. The increase of the glucose concentration causes the increase of the resonant wavelength shift, therefore this polymer-based MRR’s can be used for glucose sensing application.

14

AKAGIĆ, Asima, Amila VRANAC, Fuad GAŠI, Pakeza DRKENDA, Nermina SPAHO, Sanja ORUČEVIĆ ŽULJEVIĆ, Mirsad KURTOVIĆ, Osman MUSIĆ, Senad MURTIĆ, and Metka HUDINA. "Sugars, acids and polyphenols profile of commercial and traditional apple cultivars for processing." Acta agriculturae Slovenica 113, no. 2 (July 29, 2019): 239. http://dx.doi.org/10.14720/aas.2019.113.2.5.

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Three commercial apple cultivars ('Jonagold', 'Granny Smith' and 'Idared') and the local apple cultivar ('Prijedorska Zelenika') from Bosnia and Herzegovina were analysed by HPLC-MS for the content of phenolic compounds in peel and pulp as well content of individual sugars and organic acids. Catechin, (-)-epicatechin, chlorogenic acid, caffeic acid, quercetin 3-<em>O</em>-xyloside, quercetin 3-<em>O</em>-arabinoside, quercetin 3-<em>O</em>-rhamnoside, quercetin 3-<em>O</em>-rutinoside, quercetin 3-<em>O</em>-galactoside and quercetin 3-<em>O</em>-glucoside were identified in apple peel and (-)-epicatechin, chlorogenic acid and caffeic acid in apple pulp at all observed cultivars. The total sugars content of analysed apple cultivars ranged between 91.61 and 105.45 g kg<sup>-1 </sup>FM, while the total organic acids content was from 5.70 to 15.05 g kg<sup>-1 </sup>FM. The levels of total organic acids and sugars, glucoce/fructose ratio and sugar/acid ratio were affected by cultivars. The mean content of total phenolic compounds was between 427.92 and 1457.95 mg kg<sup>-1 </sup>FM in peel and from 113.58 to 439.83 mg kg<sup>-1 </sup>FM in pulp and depending upon the cultivars. The presented data clearly demonstrated that traditional apple cultivar ('Prijedorska Zelenika') had significantly higher individual phenolic compounds in pulp in comparison to the commercial cultivars, i.e., 'Idared', 'Jonagold' and 'Granny Smith' and with respect of that 'Prijedorska Zelenika' is recommended as raw material for cloudy juice processing.

15

Chen, Peidong, Zhiwei Shen, Qianqian Wang, Bingna Zhang, Zerui Zhuang, Jiefen Lin, Yuanyu Shen, Yanzhi Chen, Zhuozhi Dai, and Renhua Wu. "Reduced Cerebral Glucose Uptake in an Alzheimer’s Rat Model With Glucose-Weighted Chemical Exchange Saturation Transfer Imaging." Frontiers in Aging Neuroscience 13 (March 17, 2021). http://dx.doi.org/10.3389/fnagi.2021.618690.

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A correlation between the abnormal cerebral glucose metabolism and the progression of Alzheimer’s disease (AD) has been found in previous studies, suggesting that glucose alterations may be used to predict the histopathological diagnosis in AD. In this study, we investigated the dynamic changes of cerebral glucose uptake in vivo using MR glucose chemical exchange saturation transfer (glucoCEST) imaging in a rat model of AD with an intracerebroventricular (i.c.v) injection of amyloid Aβ-protein (25–35), confirmed by Morris water maze and Nissl staining. In total, 6 rats in the AD group and 6 rats in the control group that were given an injection of sterile normal saline were included. At 28 days after injection, all rats performed a 7.0 T MR exanimation, including glucoCEST, diffusion tensor imaging (DTI) and hippocampus magnetic resonance spectra (MRS), to detect the possible metabolic and structural changes in the rat brain. A significantly elevated brain glucoCEST signal in the brain of AD rats was observed, and a decreased brain glucose uptake was also explored during the progression of glucose infusion compared with those in rats of the control group. In addition, there is a significant positive correlation between glucoCEST enhancement (GCE) and myo-Inosito (Ins) in the AD group and the control group (P < 0.05). A significantly reduced number of neurons in the cortex and hippocampus in AD rats combined with the significantly longer escape and a decreased number of crossings were verified at 28 days after Aβ25–35 injection by Nissl staining and Morris water maze, respectively. Our results indicated that an abnormal brain glucose mechanism in AD rats could be detected by glucoCEST imaging, suggesting a new method to explore the occurrence and progress of diabetes-related AD or dementia.

16

Schache, Daniel, Ajay Peddi, Ali Nahardani, Cornelius Faber, and Verena Hoerr. "Corrections for Rabi oscillations in cardiac chemical exchange saturation transfer MRI under the influence of very short preparation pulses." NMR in Biomedicine, December 19, 2023. http://dx.doi.org/10.1002/nbm.5081.

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AbstractVery short chemical exchange saturation transfer (CEST) pulses are beneficial in cardiac continuous wave (cw) CEST MRI, especially in small animals because of their rapid heartbeat; however, they result in signal modulations caused by Rabi oscillations. Therefore, we implemented two different filter techniques, DOwnsampling by SEparation of CEST spectrum into two parts (DOSE) and time domain (TD)‐based filtering, to correct for these signal corruptions, allowing a reliable quantification of glucose‐weighted CEST (glucoCEST) MRI contrast. In our study, cw CEST measurements were performed on a 9.4‐T small animal BioSpec system using CEST pulses in the range of 10 to 200 ms. Experimental dependencies of Rabi oscillations on key MRI parameters were validated by Bloch–McConnell (BM) simulations. Filter efficiency was explored in a glucose concentration series as well as in the myocardium of healthy mice (n = 8), and glucoCEST contrast was subsequently quantified. The experimental results showed that the impact of Rabi oscillations on CEST spectra increased with decreasing CEST pulse length, optimized B0 homogeneity, and shorter T2 relaxation time, in accordance with results from BM simulations. Both investigated filter techniques reduced these signal modulations significantly, with DOSE filtering preserving the amplitude and TD filtering the spectral information of CEST data more accurately. Upon filter application, a significant decrease in glucoCEST contrast in the myocardium of healthy mice was observed after glucose infusion (pTD = 0.0079, pDOSE = 0.0044). To conclude, this study offers comprehensive experimental insights into Rabi oscillations within CEST MRI data along with methodological considerations that could be further advanced into a robust and precise cardiac cw CEST protocol by integrating DOSE and TD filtering into the standard CEST analysis pipeline.

17

"Glucose chemical exchange saturation transfer (glucoCEST) to image enhanced glucose uptake in tumor tissues." Science-Business eXchange 6, no. 30 (August 2013): 809. http://dx.doi.org/10.1038/scibx.2013.809.

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18

Wu, Yulun, Sophie H. A. E. Derks, Tobias C. Wood, Erik de Blois, Astrid A. M. van der Veldt, Marion Smits, and Esther A. H. Warnert. "Improved postprocessing of dynamic glucose-enhanced CEST MRI for imaging brain metastases at 3 T." European Radiology Experimental 7, no. 1 (December 8, 2023). http://dx.doi.org/10.1186/s41747-023-00390-5.

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Abstract Background Dynamic glucose-enhanced (DGE) chemical exchange saturation transfer (CEST) has the potential to characterize glucose metabolism in brain metastases. Since the effect size of DGE CEST is small at 3 T (< 1%), measurements of signal-to-noise ratios are challenging. To improve DGE detection, we developed an acquisition pipeline and extended image analysis for DGE CEST on a hybrid 3-T positron emission tomography/magnetic resonance imaging system. Methods This cross-sectional study was conducted after local ethical approval. Static Z-spectra (from -100 to 100 ppm) were acquired to compare the use of 1.2 versus 2 ppm to calculate static glucose-enhanced (glucoCEST) maps in 10 healthy volunteers before and after glucose infusion. Dynamic CEST images were acquired during glucose infusion. Image analysis was optimized using motion correction, dynamic B0 correction, and principal component analysis (PCA) to improve the detection of DGE CEST in the sagittal sinus, cerebrospinal fluid, and grey and white matter. The developed DGE CEST pipeline was applied to four patients diagnosed with brain metastases. Results GlucoCEST was strongest in healthy tissues at 2 ppm. Correcting for motion, B0, and use of PCA locally improved DGE maps. A larger contrast between healthy tissues and enhancing regions in brain metastases was found when dynamic B0 correction and PCA denoising were applied. Conclusion We demonstrated the feasibility of DGE CEST with our developed acquisition and analysis pipeline at 3 T in patients with brain metastases. This work enables a direct comparison of DGE CEST to 18F-fluoro-deoxy-D-glucose positron emission tomography of glucose metabolism in patients with brain metastases. Relevance statement Contrast between brain metastasis and healthy brain tissue in DGE CEST MR images is improved by including principle component analysis and dynamic magnetic field correction during postprocessing. This approach enables the detection of increased DGE CEST signal in brain metastasis, if present. Key points • Despite the low signal-to-noise ratio, dynamic glucose-enhanced CEST MRI is feasible at 3 T. • Principal component analyses and dynamic magnetic field correction improve DGE CEST MRI. • DGE CEST MRI does not consequently show changes in brain metastases compared to healthy brain tissue. • Increased DGE CEST MRI in brain metastases, if present, shows overlap with contrast enhancement on T1-weighted images. Graphical Abstract

19

Zaiss, Moritz, Annasofia Anemone, Steffen Goerke, Dario Livio Longo, Kai Herz, Rolf Pohmann, Silvio Aime, et al. "Quantification of hydroxyl exchange of D‐Glucose at physiological conditions for optimization of glucoCEST MRI at 3, 7 and 9.4 Tesla." NMR in Biomedicine 32, no. 9 (July 17, 2019). http://dx.doi.org/10.1002/nbm.4113.

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20

"Arterial Input Functions and Tissue Response Curves in Dynamic Glucose-Enhanced (DGE) Imaging: Comparison Between glucoCEST and Blood Glucose Sampling in Humans." Tomography 4, no. 4 (December 2018): 164–71. http://dx.doi.org/10.18383/j.tom.2018.00025.

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21

Capozza, Martina, Annasofia Anemone, Chetan Dhakan, Melania Della Peruta, Martina Bracesco, Sara Zullino, Daisy Villano, Enzo Terreno, Dario Livio Longo, and Silvio Aime. "GlucoCEST MRI for the Evaluation Response to Chemotherapeutic and Metabolic Treatments in a Murine Triple-Negative Breast Cancer: A Comparison with[18F]F-FDG-PET." Molecular Imaging and Biology, August 12, 2021. http://dx.doi.org/10.1007/s11307-021-01637-6.

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22

Dickie, Ben R., Tao Jin, Ping Wang, Rainer Hinz, William Harris, Hervé Boutin, Geoff JM Parker, Laura M. Parkes, and Julian C. Matthews. "Quantitative kinetic modelling and mapping of cerebral glucose transport and metabolism using glucoCESL MRI." Journal of Cerebral Blood Flow & Metabolism, June 23, 2022, 0271678X2211088. http://dx.doi.org/10.1177/0271678x221108841.

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Chemical-exchange spin-lock (CESL) MRI can map regional uptake and utilisation of glucose in the brain at high spatial resolution (i.e sub 0.2 mm3 voxels). We propose two quantitative kinetic models to describe glucose-induced changes in tissue R1ρ and apply them to glucoCESL MRI data acquired in tumour-bearing and healthy rats. When assuming glucose transport is saturable, the maximal transport capacity ( Tmax) measured in normal tissue was 3.2 ± 0.6 µmol/min/mL, the half saturation constant ( Kt) was 8.8 ± 2.2 mM, the metabolic rate of glucose consumption ( MRglc) was 0.21 ± 0.13 µmol/min/mL, and the cerebral blood volume ( vb) was 0.006 ± 0.005 mL/mL. Values in tumour were: Tmax = 7.1 ± 2.7 µmol/min/mL, Kt = 14 ± 1.7 mM, MRglc = 0.22 ± 0.09 µmol/min/mL, vb = 0.030 ± 0.035 mL/mL. Tmax and Kt were significantly higher in tumour tissue than normal tissue (p = 0.006 and p = 0.011, respectively). When assuming glucose uptake also occurs via free diffusion, the free diffusion rate ( kd) was 0.061 ± 0.017 mL/min/mL in normal tissue and 0.12 ± 0.042 mL/min/mL in tumour. These parameter estimates agree well with literature values obtained using other approaches (e.g. NMR spectroscopy).

23

Vifta, Rissa, Wilantika Wilantika, and Yustisia Dian Advistasari. "STUDI IN VITRO POTENSI ANTIOKSIDAN DAN AKTIFITAS ANTIDIABETES FRAKSI ETIL ASETAT BUAH PARIJOTO (Medinilla speciosa B.)." Jurnal Tumbuhan Obat Indonesia 12, no. 2 (December 13, 2019). http://dx.doi.org/10.22435/jtoi.v12i2.1160.

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ABSTRACT Parijoto fruit (Medinilla speciosa B) contains the flavonoid which is one of the phenolic groups compounnd. Flavonoids has biological activities as anti free radical and antionxidants. The aim of this research was to evaluate the potency of ethyl acetat fraction of M.speciosa B. Extract as an antioxidants and antidiabetic. Evaluation of antioxidants activity was carried out by in vitro assay using the ABTS method (2.2 azinobis (3-ethylbenzotiazolin) -6-sulfonic acid), while the antidiabetic assay was carried out using the Nelson-Somogyi method. Research begins with the process of determination, extraction, fravtionation and contiunued by examination of each variable. The parameters of antioxidants activity was determined by IC50 values, while antidiabetic activity was measured by percentage of decreasing of glucoce levels. The results of antioxidants activity showed that ethyl acetate fraction of M. Speciosa B. had antioxidants activity with an IC50 value of 4,246 ppm with a very strong category. In line with these results, ethyl acetate fraction of M. speciosa B. had reduced glucoce levels with an optimal decrease of 50.21% a concentration of 40 ppm. ABSTRAK Buah Parijoto (Medinilla speciosa B.) mengandung senyawa aktif flavonoid yang merupakan salah satu golongan fenolik. Flavonoid memiliki aktifitas biologis sebagai antiradikal bebas dan antioksidan. Penelitian dilakukan dengan tujuan mengetahui kemampuan fraksi etil asetat M. speciosa B sebagai antioksidan dan antidiabetes. Pengujian aktifitas antioksidan dilakukan secara in vitro dengan metode ABTS (2,2 azinobis (3-etilbenzotiazolin)-6-asam sulfonat), sedangkan uji antidiabetes dilakukan menggunakan metode Nelson-Somogyi. Penelitian diawali dengan proses determinasi, ekstraksi, fraksinasi, dan dilanjutkan dengan pengujian pada masing-masing variabel. Parameter aktifitas antioksidan diwujudkan dengan nilai IC50, sedangkan aktiftas antidiabetes diukur dengan persen penurunan kadar glukosa. Hasil pengujian aktifitas antioksidan menunjukkan bahwa fraksi etil asetat memiliki aktifitas antioksidan dengan nilai IC50 sebesar 4.14±0.08 ppm dengan kategori sangat kuat. Sejalan dengan hasil tersebut, fraksi etil asetat Buah Parijoto (M. speciosa B.) memilili kemampuan dalam menurunkan kadar glukosa dengan penurunan secara optimal sebesar 50.21±0.47% pada konsentrasi 40 ppm.