Optimization of flavonoid extraction from mulberry leaves and development of functional noodle products
Main Article Content
Keywords
Antioxidant; Mulberry leaf; Mulberry leaf noodles; Process optimization; Response surface methodology; Total flavonoids
Abstract
This study aimed to optimize the extraction of flavonoids from mulberry leaves and their application in functional noodles to enhance the valorization of mulberry leaf resources. The dry-up method was selected as the optimal pretreatment based on ultraviolet spectrophotometry. Ultrasonic-assisted extraction was optimized by single-factor experiments and response surface methodology (RSM). The extract was incorporated into noodles as powder, juice, or pulp at varying concentrations to assess quality attributes and antioxidant activities. The dry-up method has proved to be most effective for drying mulberry leaves. The optimal extraction conditions identified via RSM included a solid–liquid ratio of 1:40 g/mL, 56% ethanol, a temperature of 60°C, and a time of 30 min, yielding a total flavonoid content of 26.04%. Three noodle formulations were developed: mulberry leaf powder (1.0% powder, 0.5% baking soda, and 1.0% salt), mulberry leaf juice (16.0% juice, 0.3% baking soda, and 1.0% salt), and mulberry leaf pulp (20.0% pulp, 0.4% baking soda, and 1.1% salt). The flavonoid content was 1.317 ± 0.01 mg/g for mulberry leaf powder noodles, 1.603 ± 0.01 mg/g for mulberry leaf juice noodles, and 1.413 ± 0.02 mg/g for mulberry leaf pulp noodles. All noodles exhibited significant antioxidant activity, with the mulberry leaf pulp variant demonstrating the highest radical scavenging capacity against both radical cation of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+) and 2,2-diphenyl-1-picrylhydrazyl (DPPH), outperforming the other two forms. The established extraction method is efficient and applicable for producing flavonoid-enriched noodles with improved antioxidant properties. This approach supports the development of functional grain foods and offers a practical route for the high-value utilization of mulberry leaves.
References
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Kazemi M., Khodaiyan F., Labbafi M., Saeid Hosseini S. and Hojjati M. 2019. Pistachio green hull pectin: optimization of microwave-assisted extraction and evaluation of its physicochemical, structural and functional properties. Food Chemistry 271: 663–672. https://doi.org/10.1016/j.foodchem.2018.07.212
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Li W., Zhang D.X., Liu L.J., Lv Q., Yuan M.Y., Zhao Y. and Li T. 2022. Extraction and antioxidant activity of total flavonoids from licorice cells. Feed Research 45(24): 68–72. https://doi.org/10.13557/j.cnki.issn1002-2813.2022.24.014
Lin Z.W., Gan T.T., Huang Y.Z., Bao L.J., Liu S., Cui X.P., Wang H.X., Jiao F., Zhang M.J., Su C., and Qian Y.H. 2022. Anti-inflammatory activity of mulberry leaf flavonoids in vitro and in vivo. International Journal of Molecular Sciences 23(14): 7694.
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Lu, Z.L. (Ed. & Annot.). (1995). Mawangdui medical books. Liaoning Science and Technology Press.
Ma G., Chai X., Hou G., Zhao F. and Meng Q. 2022. Phytochemistry, bioactivities and future prospects of mulberry leaves: a review. Food Chemistry 372: 131335. https://doi.org/10.1016/j.foodchem.2021.131335
Ma X.H., Liu J.S., Zhang W.L., Li F. and Sun C. 2015. Research on staple foodization of Chinese mixed grain noodles. Food Research and Development 36(20): 181–184. (In Chinese)
National Pharmacopoeia Commission. 2020. Pharmacopoeia of the People’s Republic of China (Part One). Beijing: China Medical Science Press.
Shi J.B., Sui Y., Cai S., He J.J., Xiong T., Fan C.H., Chen X.L., Jia Z.W., Wang S.H., Cai F., Jiang X.J. and Mei X. 2023. Optimization of buckwheat noodle formulation and its in vitro digestive properties. Food Research and Development 44(10): 153–161.
Sivamaruthi B.S., Kesika P., Prasanth M.I. and Chaiyasut C. 2018. A mini review on antidiabetic properties of fermented foods. Nutrients 10: 1973. https://doi.org/10.3390/nu10121973
Sun G.Y., Li H., Yang C.H., Gan J.W., Tao G.S., Wang Q.M. and Yang D. 2022. Optimization of extraction process for total flavonoids from epimedium by response surface methodology. Chemical and Biological Engineering 39(11): 37–41. https://doi.org/10.3969/j.issn.1672-5425.2022.11.008
Tao S.J., Xu S., Cheng J. and Wang A.L. 2014. Preparation and functional component determination of mulberry leaf noodles. Journal of Southwest University (Natural Science Edition) 36(02): 36–40. https://doi.org/10.13718/j.cnki.xdzk.2014.02.006
Thakur M., Belwal T., Agarwal A., Amin T., Arzoo S., Bansal M. and Zargar I.A. 2023. Bioactive Components: A Sustainable System for Good Health and Well-Being. Springer, Singapore. https://doi.org/10.1007/978-981-19-2366-1
Varghese S.M. and Thomas J. 2019. Polyphenolic constituents in mulberry leaf extract (M. latifolia L. cv. BC259) and its antidiabetic effect in streptozotocin induced diabetic rats. Pakistan Journal of Pharmaceutical Sciences 32(1): 69–74.
Wang J., Chen X., Gao W.B., Zhang Z.Y., Zhang Y.N. and Liu T.Y. 2022a. Optimization of ultrasound-assisted extraction process and physiological activity of polysaccharides from Chrysanthemum officinale by response surface methodology. China Food Additives 33(2): 100–109. https://doi.org/10.19804/j.issn1006-2513.2022.02.014
Wang T.T., Liu X.R., Jia J. and Zhang L.L. 2022b. Optimization of ultrasonic-enzyme-assisted extraction of total flavonoids from Eucommia ulmoides leaves. Feed Research 45(17): 69–74. https://doi.org/10.13557/j.cnki.issn1002-2813.2022.17.016
Wen H.C., Zhang X.Y. and Li H.J. 2022. Comprehensive evaluation of mulberry leaf quality under different fixation methods based on principal component analysis. Acta Sericologica Sinica 48(3): 247–260. https://doi.org/10.13441/j.cnki.cykx.2022.03.007
Weremfo A., Abassah-Oppong S., Adulley F., Dabie K. and Seidu-Larry S. 2023. Response surface methodology as a tool to optimize the extraction of bioactive compounds from plant sources. Journal of the Science of Food and Agriculture 103(1): 26–36. https://doi.org/10.1002/jsfa.12121
Xie Q.R., Liu X.R., Xiao S.S., Pan W., Wu Y., Ding W.P., Lyu Q.Y., Wang X.D., and Fu Y. 2022. Effect of mulberry leaf polysaccharides on the baking and staling properties of frozen dough bread. Journal of the Science of Food and Agriculture 102(13): 6071–6079.
Zhang X.Z., Liu Y. and Mang L. 2021. Optimization of mulberry leaf flavonoid extraction by response surface methodology and study on antioxidant properties. Feed Industry. 42(19): 42–48. https://doi.org/10.13302/j.cnki.fi.2021.19.007
Zulkifli S.A., Abd Gani S.S., Zaidan U.H. and Halmi M.I.E. 2020. Optimization of total phenolic and flavonoid contents of defatted pitaya (Hylocereus polyrhizus) seed extract and its antioxidant properties. Molecules 25(4): 787. https://doi.org/10.3390/ molecules 25040787
Awad A.M., Kumar P., Ismail-Fitry M.R., Jusoh S., Ab Aziz M.F. and Sazili A.Q. 2021. Green extraction of bioactive compounds from plant biomass and their application in meat as natural antioxidant. Antioxidants 10(9): 1465. https://doi.org/10.3390/antiox10091465
Babamoradi N., Yousefi S. and Ziarati P. 2018. Optimization of ultrasound-assisted extraction of functional polysaccharides from common mullein (Verbascum thapsus L.) flowers. Journal of Food Processing and Engineering 41(8): e12851. https://doi.org/10.1111/jfpe.12851
Cao J.S., Wei Q., Zhan J., Gao D.P., Jian B.B. and Zhang J. 2025. Optimization of the extraction process of aqueous extract of scutellaria baicalensis by response surface methodology and its antibacterial activity. Journal of Mountain Agriculture and Biology 44 (03), 1-9+23. https://doi.org/10.15958/j.cnki.sdnyswxb.2025.03.001
Cao J., Zhang X.Y., Zhou B., Lu Y. and Zhu F.Y. 2019. Study on extraction technology of total flavonoids from mulberry leaves. Food Fermentation Science and Technology 55(4): 66–70. https://doi.org/10.3969/j.issn.1674-506X.2019.04-012
Chan E.W., Wong S.K., Tangah J., Inoue T. and Chan H.T. 2020. Phenolic constituents and anticancer properties of Morus alba (white mulberry) leaves. Journal of Integrated Medicine 18(3): 189–195. https://doi.org/10.1016/j.joim.2020.02.006
Chen X., Su J.P. and Bai J. 2023. Effect of mulberry leaf extract based on PI3K/AKT pathway in type 2 diabetes mellitus rats. Journal of Experimental & Clinical Medicine 22(8): 795–800.
Chen Y., Yin L., Zhao Z.L.G., Shu Z.X., Yuan H.L., Fu C., Lv C. and Lin J.C. 2017. Optimization of the ultrasound-assisted extraction of antioxidant phloridzin from Lithocarpus polystachyus Rehd. using response surface methodology. Journal of Separation Science 40(22): 4329–4337. https://doi.org/10.1002/jssc.201700686
Chen K.Y., Zhu Y.J., Sheng X.E. and Liu Z. 2024. Influences of different drying temperature on quality and noodle texture characteristics of mulberry leaf powder. Guangzhou Guangzhou Chemical Industry. 52 (05): 58–60+82.
Dai R., Du M.Y., Fu J.J., Sun H., Xie W., Wu J.Y. and Wang J.H. 2023. Quality and antioxidant activity of fresh noodles with different amounts of mulberry leaf powder. Modern Food Science and Technology 39(12): 226–233.
Deng Q.L., Liu M.W., Shen J., Daguti T.A., Chen X.S., Xu W.S. and Xiao H. 2024. Total flavonoids, total polyphenols content and antioxidant activity of mulberry leaves from different regions. China Food Additive 35(3): 130–137. https://doi.org/10.19804/j.issn1006-2513.2024.3.016
Feng Y.J., Zeng Y.Q., Chen J., Zhu W.Q. and Zhou J.M. 2023. Protective effect of mulberry leaf extract on APAP-induced acute liver injury in mice. Huaxia Medical Journal 36(2): 38–42. https://doi.org/10.19296/j.cnki.1008-2409.2023-02-00
Fu X., Li L., Zhou W. and Dong W. 2013. Fuzzy mathematical evaluation of the production formula of mulberry leaf hanging noodles. Food Science and Technology 38(12): 180–183. https://doi.org/10.13684/j.cnki.spkj.2013.12.041
Huang J., Gong B.Y., Qi W.L., Fu L., Wang Z.D. and Wang T. 2021. Design process of high-quality mulberry leaf noodles. Food Industry 42(5): 10–13. (In Chinese)
Jeong S.Y., Kim E., Zhang M., Lee Y.S., Ji B., Lee S.H., Cheong Y.E., Yun S.I., Kim Y.S., Kim K.H., Kim M.S., Chun H.S. and Kim S. 2021. Antidiabetic effect of noodles containing fermented lettuce extracts. Metabolites 11(8): 520. https://doi.org/10.3390/metabo11080520
Kadam R.A., Dhumal N.D. and Khyade V. 2019. The mulberry, Morus alba (L.): the medicinal herbal source for human health. International Journal of Current Microbiology and Applied Sciences 8(4): 2941–2964. https://doi.org/10.20546/ijcmas.2019.804.341
Kazemi M., Khodaiyan F., Labbafi M., Saeid Hosseini S. and Hojjati M. 2019. Pistachio green hull pectin: optimization of microwave-assisted extraction and evaluation of its physicochemical, structural and functional properties. Food Chemistry 271: 663–672. https://doi.org/10.1016/j.foodchem.2018.07.212
Levent H., Koyuncu M., Bilgiçli N., Adıgüzel E. and Dedeoğlu M. 2020. Improvement of chemical properties of noodle and pasta using dephytinized cereal brans. Food Science and Technology (LWT) 134: 110123. https://doi.org/10.1016/j.lwt.2020.109123. (Note: DOI in original seems incorrect, corrected based on common practice for LWT)
Li R., Wang C., Chen Y., Li N., Wang Q., Zhang M., He C. and Chen H. 2021. A combined network pharmacology and molecular biology approach to investigate the active ingredients and potential mechanisms of mulberry (Morus alba L.) leaf on obesity. Phytomedicine 92: 153714. https://doi.org/10.1016/j.phymed.2021.153714
Li K., Zhang Z.J., Du Y.X., Li C.X., Zhang Y., Wang E.J. and Zhang D.Z. 2024. Nutritional and functional components in leaves of introduced fruit mulberry and leaf mulberry varieties and their antioxidant activities. Science and Technology of Food Industry 45 (20), 232-239. https://doi.org/10.13386/j.issn1002-0306.2023100104.
Li W., Zhang D.X., Liu L.J., Lv Q., Yuan M.Y., Zhao Y. and Li T. 2022. Extraction and antioxidant activity of total flavonoids from licorice cells. Feed Research 45(24): 68–72. https://doi.org/10.13557/j.cnki.issn1002-2813.2022.24.014
Lin Z.W., Gan T.T., Huang Y.Z., Bao L.J., Liu S., Cui X.P., Wang H.X., Jiao F., Zhang M.J., Su C., and Qian Y.H. 2022. Anti-inflammatory activity of mulberry leaf flavonoids in vitro and in vivo. International Journal of Molecular Sciences 23(14): 7694.
Liu X., Zhao C., An Y.X., Lei Y.W., Zhao Y. and Zhang J. 2023. Preparation of yam whole flour noodles and their effects on noodle quality. Food Research and Development 44(20): 107–114. https://doi.org/10.12161/j.issn.1005-6521.2023.20.015
Lu, Z.L. (Ed. & Annot.). (1995). Mawangdui medical books. Liaoning Science and Technology Press.
Ma G., Chai X., Hou G., Zhao F. and Meng Q. 2022. Phytochemistry, bioactivities and future prospects of mulberry leaves: a review. Food Chemistry 372: 131335. https://doi.org/10.1016/j.foodchem.2021.131335
Ma X.H., Liu J.S., Zhang W.L., Li F. and Sun C. 2015. Research on staple foodization of Chinese mixed grain noodles. Food Research and Development 36(20): 181–184. (In Chinese)
National Pharmacopoeia Commission. 2020. Pharmacopoeia of the People’s Republic of China (Part One). Beijing: China Medical Science Press.
Shi J.B., Sui Y., Cai S., He J.J., Xiong T., Fan C.H., Chen X.L., Jia Z.W., Wang S.H., Cai F., Jiang X.J. and Mei X. 2023. Optimization of buckwheat noodle formulation and its in vitro digestive properties. Food Research and Development 44(10): 153–161.
Sivamaruthi B.S., Kesika P., Prasanth M.I. and Chaiyasut C. 2018. A mini review on antidiabetic properties of fermented foods. Nutrients 10: 1973. https://doi.org/10.3390/nu10121973
Sun G.Y., Li H., Yang C.H., Gan J.W., Tao G.S., Wang Q.M. and Yang D. 2022. Optimization of extraction process for total flavonoids from epimedium by response surface methodology. Chemical and Biological Engineering 39(11): 37–41. https://doi.org/10.3969/j.issn.1672-5425.2022.11.008
Tao S.J., Xu S., Cheng J. and Wang A.L. 2014. Preparation and functional component determination of mulberry leaf noodles. Journal of Southwest University (Natural Science Edition) 36(02): 36–40. https://doi.org/10.13718/j.cnki.xdzk.2014.02.006
Thakur M., Belwal T., Agarwal A., Amin T., Arzoo S., Bansal M. and Zargar I.A. 2023. Bioactive Components: A Sustainable System for Good Health and Well-Being. Springer, Singapore. https://doi.org/10.1007/978-981-19-2366-1
Varghese S.M. and Thomas J. 2019. Polyphenolic constituents in mulberry leaf extract (M. latifolia L. cv. BC259) and its antidiabetic effect in streptozotocin induced diabetic rats. Pakistan Journal of Pharmaceutical Sciences 32(1): 69–74.
Wang J., Chen X., Gao W.B., Zhang Z.Y., Zhang Y.N. and Liu T.Y. 2022a. Optimization of ultrasound-assisted extraction process and physiological activity of polysaccharides from Chrysanthemum officinale by response surface methodology. China Food Additives 33(2): 100–109. https://doi.org/10.19804/j.issn1006-2513.2022.02.014
Wang T.T., Liu X.R., Jia J. and Zhang L.L. 2022b. Optimization of ultrasonic-enzyme-assisted extraction of total flavonoids from Eucommia ulmoides leaves. Feed Research 45(17): 69–74. https://doi.org/10.13557/j.cnki.issn1002-2813.2022.17.016
Wen H.C., Zhang X.Y. and Li H.J. 2022. Comprehensive evaluation of mulberry leaf quality under different fixation methods based on principal component analysis. Acta Sericologica Sinica 48(3): 247–260. https://doi.org/10.13441/j.cnki.cykx.2022.03.007
Weremfo A., Abassah-Oppong S., Adulley F., Dabie K. and Seidu-Larry S. 2023. Response surface methodology as a tool to optimize the extraction of bioactive compounds from plant sources. Journal of the Science of Food and Agriculture 103(1): 26–36. https://doi.org/10.1002/jsfa.12121
Xie Q.R., Liu X.R., Xiao S.S., Pan W., Wu Y., Ding W.P., Lyu Q.Y., Wang X.D., and Fu Y. 2022. Effect of mulberry leaf polysaccharides on the baking and staling properties of frozen dough bread. Journal of the Science of Food and Agriculture 102(13): 6071–6079.
Zhang X.Z., Liu Y. and Mang L. 2021. Optimization of mulberry leaf flavonoid extraction by response surface methodology and study on antioxidant properties. Feed Industry. 42(19): 42–48. https://doi.org/10.13302/j.cnki.fi.2021.19.007
Zulkifli S.A., Abd Gani S.S., Zaidan U.H. and Halmi M.I.E. 2020. Optimization of total phenolic and flavonoid contents of defatted pitaya (Hylocereus polyrhizus) seed extract and its antioxidant properties. Molecules 25(4): 787. https://doi.org/10.3390/ molecules 25040787
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Oct 30, 2025
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