Nutrition, Phytochemicals, Antioxidants, and Cytotoxicity of Sweet Potato Leaf Tea

Authors

  • Jinnawat Manasathien Program of Biology, Institute of Science and Technology, Nakhon Ratchasima Rajabhat University, Nakhon Ratchasima 30000, Thailand
  • Piyanut Khanema Department of Biology, Faculty of Science, Mahasarakham University, Maha Sarakham 44150, Thailand

DOI:

https://doi.org/10.48048/tis.2022.5766

Keywords:

Sweet potato leaves, Phytochemicals, Antioxidant activity, Cytotoxicity, Colour parameter

Abstract

Due to their nutritional loadings and the value-added aspect, fresh leaves of 5 sweet potato varieties were screened for phytochemicals and used to produce herbal teas. The teas were observed for their proximate components, antioxidants, antioxidative activity, cytotoxicity and colour parameters under brewing at 60, 80 and 100 ºC for 3, 5, 7 and 10 min. Tannins, phenolic compounds, saponins, flavonoids, phytosterols and alkaloids were contained in almost all varieties, whereas cardiac glycosides were dominant only in WP (white skin and purple flesh root) fresh leaves. Results for proximate components found that WP tea was prominent with the enrichment of crude fat (16.71 g/100 g of tea), chlorophyll b (29.41 mg/100 g of tea), cyanidin-3-glucoside (83.59 mg/100 g of tea), pelargonidin-3-glucoside (72.30 mg/100 g of tea) and tannins (1,994.81 mg TAE/100 g of tea). This was followed by RO (red skin and orange flesh root) with more protein content (0.13 g/100 g of tea). In the antioxidant test, OO (orange skin and orange flesh root) had the highest total phenolic content (1,260.92 mg GAE/100 g of tea) and offered the greatest potential of antioxidative activity (12,218.44 mg GAE/100 g of tea). No teas showed any signs of cytotoxicity (LC50 > 1,000 µg/mL). Almost all the tea was green in colour, but a yellow colour indicating lutein or its influence was also detected. In conclusion, WP, RO and OO tea were predominantly served as a low-price healthy beverage with high nutrient levels and antioxidative properties.

HIGHLIGHTS

  • Edible sweet potato leaves can be served as a low-cost healthy tea beverage
  • Sweet potato leaf teas enrich of medicinal bioactivities such as cyanidin-3-glucoside, pelargonidin-3-glucoside, tannins, and total phenolic compounds
  • Sweet potato leaf teas have strong antioxidative activity


GRAPHICAL ABSTRACT

Downloads

Download data is not yet available.

References

Food and Agricultural Organization (FAO). FAO statistics, Food and Agricultural Organization, Rome, Italy, Available at: http://www.fao.org/statistics/en/, accessed September 2019.

P Prakash, P Kishore, D Jaganathan, S Immanual and PS Sivakumar. The status, performance and impact of sweet potato cultivation on farming communities of Odisha, India. In: Proceedings of the 30th International Conference of Agricultural Economists, Vancouver, Canada. 2018.

TRIDGE. Fresh or dried sweet potato, Available at: https://www.tridge.com/hs-codes/071420-sweet-potatoes-fresh-or-dried, accessed September 2020.

E Menelaou, A Kachatryan, JN Losso, M Cavalier and DL Bonte. Lutein content in sweet potato leaves. Hortic. Sci. 2006; 41, 1269-71.

H Sun, T Mu, L Xi, M Zhang and J Chen. Sweet potato (Ipomoea batatas L.) leaves as nutritional and functional foods. Food Chem. 2014; 156, 380-9.

SM Hue, AN Boyce and C Somasundram. Comparative study on the antioxidant activity of leaf extract and carotenoids extract from Ipomoea batatas var. Oren (Sweet potato) leaves. Int. Sch. Sci. Res. Innov. 2011; 5, 604-7.

SM Hue, AN Boyce and C Somasundram. Antioxidant activity, phenolic and flavonoid contents in the leaves of different varieties of sweet potato (Ipomoea batatas). Aust. J. Crop Sci. 2012; 6, 375-80.

L Cui, CQ Liu, DJ Li and JF Song. Effect of processing on taste quality and health-relevant functionality of sweet potato tips. Agric. Sci. China 2011; 10, 456-62.

M Nagai, M Tani, Y Kishimoto, M Iizuka, E Saita, M Toyozaki, T Kamiya, M Ikeguchi and K Kondo. Sweet potato (Ipomoea batatas L.) leaves suppressed oxidation of low density lipoprotein (LDL) in vitro and in human subjects. J. Clin. Biochem. Nutr. 2011; 48, 203-8.

R Nagamine, S Ueno, M Tsubata, K Yamaguchi, K Takagaki, T Hira, H Hara and T Tsuda. Dietary sweet potato (Ipomoea batatas L.) leaf extract attenuates hyperglycemia by enhancing the secretion of glucagon-like peptide-1 (GLP-1). Food Funct. 2014; 5, 2309-16.

T Thappakorn. Tea. 1st ed. Julalongkorn Publishing, Bangkok, Thailand, 2014, p. 40-3.

Land Development Department. Operation manual: Analysis of chemical soil property, Available at: http//www.http://www.ldd.go.th/PMQA/2553/Manual/OSD-03.pdf, accessed January 2020.

KS Banu and L Cathrine. General techniques involved in phytochemical analysis. Int. J. Adv. Res. Chem. Sci. 2015; 2, 25-32.

JB Harborne. Phytochemical methods: A guide to modern techniques of plant analysis. 1st ed. Chapman and Hall Published, London, 1973, p. 33-131.

Department of Medical Sciences. Standard methods for food analysis Volume 1, Available at: http://bqsf.dmsc.moph.go.th/bqsfWeb/index.php/standard-methods-1/, accessed February 2020.

K Chaleekod. Food analysis. Faculty of Technology, Udon Thani Rajabhat University, Udon Thani, Thailand, 2016, p. 126.

MM Bradford. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal. Biochem. 1976; 72, 248-54.

M Dubois, KA Gilles, JK Hamilton, PA Rebers and F Smith. Colorimetric method for determination of sugars and related substances. Anal. Chem. 1956; 28, 350-6.

DI Arnon. Copper enzymes in isolated chloroplasts, polyphenoxidase in beta vulgaris. Plant Physiol. 1949; 24, 1-15.

JD Hiscox and GF Israelstam. A method for the extraction of chlorophyll from leaf tissue without maceration. Can. J. Bot. 1979; 57, 1332-4.

RE Wrolstad. Color and pigment analyses in fruit products. Oregon Agri Exp Station Bulletin: Oregon State University, Oregon, 1976, p. 17.

K Shimada, K Fujikawa, K Yahara and T Nakamura. Antioxidative properties of xanthan on the autoxidation of soybean oil in cyclodextrin emulsion. J. Agric. Food Chem. 1992; 40, 945-8.

HPS Makkar, M Bluemmel, NK Borowy and K Becker. Gravimetric determination of tannins and their correlations with chemical and protein precipitation methods. J. Sci. Food Agric. 1993; 61, 161-5.

C Sanchez-Moreno, L Plaza, BD Ancos and MP Cano. Quantitative bioactive compounds assessment and their relative contribution to the antioxidant capacity of commercial orange juices. J. Sci. Food Agric. 2003; 83, 430-9.

BN Meyer, NR Ferrigni, JE Putnam, LB Jacobsen, DE Nichols and JL McLaughlin. Brine shrimp: A convenient general bioassay for active plant constituents. Planta Med. 1982; 45, 31-4.

J Bao, Y Cai, M Sun, G Wang and H Corke. Anthocyanins, flavonols, and free radical scavenging activity of Chinese bayberry (Myrica rubra) extracts and their color properties and stability. J. Agric. Food Chem. 2005; 53, 2327-32.

S Kurniasih and DD Saputria. Phytochemical screening and gass chromatohraphy-mass spectrometer (GC-MS) analysis ethanol extract of purple sweet potato (Ipomoea batatas L.). J. Sci. Innovare 2019; 2, 28-30.

A Anastácio and IS Carvalho. Spotlight on PGI sweet potato from Europe: Study of plant part, time and solvent effects on antioxidant activity. J. Food Biochem. 2013; 37, 628-37.

B Salehi, A Venditti, M Sharifi-Rad, D Kregiel, J Sharifi-Rad, A Durazzo, M Lucarini, A Santini, EB Souto, E Novellino, H Antolak, E Azzini, WN Setzer and N Martins. The therapeutic potential of apigenin. Int. J. Mol. Sci. 2019; 20, 1305.

W Ngwa, R Kumar, D Thompson, W Lyerly, R Moore, TE Reid, H Lowe and N Toyang. Potential of flavonoid-inspired phytomedicines against COVID-19. Molecules 2020; 25, 2707.

JB Harborne. The flavonoids: advances in research since 1986. Chapman & Hall, London, 1994, p. 7-12.

EM Aldred. Pharmacology: A handbook for complementary healthcare professionals, Available at: http://doi.org/10.1016/B978-0-443-06898-0.X0001-1, accessed September 2020.

LT Chuang, RH Glew, YC Wanf, PW Yao, CC Lin, JM Presley, JS Schulze and CW Hou. Comparison of the fatty acid, amino acid, mineral and antioxidant content of sweet potato leaves grown on Matsu Island and Mainland Taiwan. Food 2011; 5, 43-7.

GR Islam, MI Nabi, MM Hoque and A Yusuf. Caffeine, polyphenol and crude fat contents in tea varieties available in Bangladesh. Bangladesh J. Bot. 2013; 42, 321-5.

A Napolitano, V Carbone, P Saggese, K Takagaki and C Pizza. Novel galactolipids from the leaves of Ipomoea batatas L.: Characterization by liquid chromatography coupled with electrospray ionization-quadrupole time-of-flight tandem mass spectrometry. J. Agric. Food Chem. 2007; 55, 10289-97.

M Harbowy and D Ballentine. Tea chemistry. Crit. Rev. Plant Sci. 1997; 16, 415-80.

M Ošťádalová, B Tremlová, J Pokorná and M Král. Chlorophyll as an indicator of green tea quality. Acta Vet. Brno 2014; 83, S103-S109.

YP Hwang, JH Choi, EH Han, HG Kim, JH Wee, KO Jung, KH Jung, KI Kwon, TC Jeong, YC Chung and HG Jeong. Purple sweet potato anthocyanins attenuate hepatic lipid accumulation through activating adenosine monophosphate-activated protein kinase in human HepG2 cells and obese mice. Nutr. Res. 2011; 31, 896-906.

JG Zhao, QQ Yan, LZ Lu and YQ Zhang. In vivo antioxidant, hypoglycemic, and anti-tumor activities of anthocyanin extracts from purple sweet potato. Nutr. Res. Pract. 2013; 7, 359-65.

AMS Azima, A Noriham and N Manshoor. Anthocyanin content in relation to the antioxidant activity and colour properties of Garcinia mangostana peel, Syzigium cumini and Clitoria ternatea extracts. Int. Food Res. J. 2014; 21, 2369-75.

S Wang, S Nie and F Zhu. Chemicals constituents and health effects of sweet potato. Food Res. Int. 2016; 89, 90-116.

MS Islam, M Yoshimoto, N Terahara and O Yamakawa. Anthocyanin compositions in sweetpotato (Ipomoea batatas L.) leaves. Biosci. Biotechnol. Biochem. 2002; 66, 2483-6.

A Ghasemsadeh, V Omidvar and HZE Jaafar. Polyphenolic content and their antioxidant activity in leaf extract of sweet potato (Ipomoea batatas). J. Med. Plants Res. 2012; 6, 2971-6.

H Sun, T Mu, L Xi and Z Song. Effects of domestic cooking methods on polyphenols and antioxidant activity of sweet potato leaves. J. Agric. Food Chem. 2014; 62, 8982-9.

J Taira, K Taira, W Ohmine and J Nagata. Mineral determination and anti-LDL oxidation activity of sweet potato (Ipomoea batatas L.) leaves. J. Food Compost. Anal. 2013; 29, 117-25.

R Amarowicz. Tannins: The new natural antioxidants? Eur. J. Lipid Sci. Technol. 2007; 109, 549-51.

P Karna, SR Gundala, MV Gupta, SA Shamsi, RD Pace, C Yates, S Narayan and R Aneja. Polyphenol-rich sweet potato greens extract inhibits proliferation and induces apoptosis in prostate cancer cells in vitro and in vivo. Carcinogenesis 2011; 32, 1872-80.

J Manasathien, K Indrapichate and KO Intarapichet. Antioxidant activity and bioefficacy of pomegranate Punica granatum Linn. peel and seed extracts. Glob. J. Pharmacol. 2012; 6, 131-41.

MCS Liu. The benefits of consuming sweet potato leaves: Helps reduce risk of chronic diseases and promotes health. J. Regen. Med. 2018; 7, 38.

I Fukuda, I Sakane, Y Yabushita, R Kodoi, S Nishiumi, T Kakuda, S Sawamura, K Kanazawa and H Ashida. Pigments in green tea leaves (Camellia sinensis) suppress transformation of the aryl hydrocarbon receptor induced by dioxin. J. Agric. Food Chem. 2004; 52, 2499-506.

International Agency for Research on Cancer (IARC). IARC working group on the evaluation of carcinogenic risks to humans: Polychlorinated dibenzo-para-dioxins and polychlorinated dibenzofurans. Lyon, France, 4-11 February 1997. IARC Monogr. Eval. Carcinog. Risks Hum. 1997; 69, 1-631.

SB Nimse and D Pal. Free radicals, natural antioxidants, and their reaction mechanisms. RSC Adv. 2015; 5, 27986-8006.

M Tomita, KI Irwin, ZJ Xie and TJ Santora. Tea pigments inhibit the production of type 1 (T(H1)) and type 2 (T(H2)) helper T cell cytokines in CD4(+) T cells. Phytother. Res. 2002; 16, 36-42.

Downloads

Published

2022-08-25