Naringin
[CAS# 10236-47-2]

Identification

• Classification: Biochemical >> Carbohydrate >> Double sugar
• Name: Naringin
• Synonyms: 7-(2-O-(6-deoxy-alpha-L-mannopyranosyl)-beta-D-glucopyranosyloxy)-2,3-dihydro-4',5,7-trihydroxyflavone; 7-[[2-O-(6-Deoxy-alpha-L-mannopyranosyl)-beta-D-glucopyranosyl]oxy]-5-hydroxy-2(S)-(4-hydroxyphenyl)-4H-1-benzopyran-4-one
• Molecular Formula: C₂₇H₃₂O₁₄
• Molecular Weight: 580.54
• CAS Registry Number: 10236-47-2
• EC Number: 233-566-4
• SMILES: C[C@H]1[C@@H]([C@H]([C@H]([C@@H](O1)O[C@@H]2[C@H]([C@@H]([C@H](O[C@H]2OC3=CC(=C4C(=O)C[C@H](OC4=C3)C5=CC=C(C=C5)O)O)CO)O)O)O)O)O

Properties

• Melting point: 171 °C (Expl.)
• Boiling point: 928.1±65.0 °C 760 mmHg (Calc.)^*
• Flash point: 308.5±27.8 °C (Calc.)^*
• Index of refraction: 1.708 (Calc.)^*
• Alpha: -91 ° (c=1,C2H5OH) (Expl.)

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H315-H319-H335
• Safety Statements: P261-P264-P264+P265-P271-P280-P302+P352-P304+P340-P305+P351+P338-P319-P321-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Specific target organ toxicity - single exposure	STOT SE	3	H335
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319

Discovery and Applications

Naringin is a flavanone glycoside belonging to the flavonoid family, primarily found in citrus fruits such as grapefruit (Citrus paradisi), pomelo (Citrus maxima), and certain bitter oranges. It was first isolated in the mid-19th century during phytochemical studies on the bitter components of citrus peel. The compound is responsible for the characteristic bitter taste of grapefruit and related fruits, and its structure was later clarified as the glycoside of naringenin with the disaccharide neohesperidose. Advances in natural product chemistry in the early 20th century allowed precise identification of naringin and other flavonoid glycosides, establishing their importance in plant defense, pigmentation, and interaction with herbivores.

The discovery of naringin’s biochemical properties paralleled growing interest in dietary flavonoids. Its hydrolysis product, naringenin, was shown to be a biologically active aglycone. Enzymes such as naringinase, a complex containing both α-L-rhamnosidase and β-D-glucosidase, became important in studies of naringin metabolism. Naringinase catalyzes the conversion of naringin into prunin and subsequently into naringenin. This enzymatic activity has been widely exploited in food and pharmaceutical industries to reduce bitterness in citrus juices and wines while simultaneously releasing bioactive flavonoids with potential health-promoting effects.

Applications of naringin span food technology, pharmacology, and medicine. In the food industry, the debittering of citrus juices is one of the earliest and most practical applications. Naringinase-treated juices retain nutritional value but lose the excessive bitterness that otherwise reduces consumer acceptability. Similar processes are used in winemaking and other fruit-based beverages, where bitterness can interfere with desirable flavor profiles. Additionally, naringin has been studied as a natural additive due to its antioxidant properties, which help protect against oxidative spoilage.

In pharmacological research, naringin has been associated with multiple bioactivities. Experimental studies have shown that naringin exhibits antioxidant effects through free radical scavenging and modulation of oxidative stress pathways. It also demonstrates anti-inflammatory activity by influencing cytokine expression and enzyme activity. In cardiovascular research, naringin has been observed to modulate lipid metabolism and protect vascular tissues in animal models. These findings have spurred investigation into its potential role in preventing atherosclerosis and metabolic disorders. Furthermore, naringin’s neuroprotective effects have been documented in preclinical studies, where it was shown to reduce neuronal damage in models of oxidative stress and ischemia.

Another key area of application relates to drug metabolism. Naringin, similar to grapefruit juice in general, is known to inhibit cytochrome P450 3A4 (CYP3A4) enzymes and P-glycoprotein in the intestine. This interaction alters the bioavailability of a variety of orally administered drugs, including certain calcium channel blockers, immunosuppressants, and statins. The so-called “grapefruit juice effect” has made naringin an important compound in pharmacokinetic research. While these interactions can sometimes increase drug efficacy, they also pose risks of adverse effects, highlighting the dual nature of naringin’s role in drug interactions.

In traditional medicine, naringin-containing citrus extracts have been used for centuries for their bitter tonic properties, digestive benefits, and circulatory support. Modern investigations continue to explore these historical applications with controlled experiments, aiming to validate and better understand the clinical relevance of these uses.

Overall, naringin represents an instructive case of a naturally occurring plant glycoside that bridges basic phytochemistry, industrial application, and biomedical relevance. Its initial discovery as a bitter principle in citrus fruits has expanded into multiple domains, ranging from food technology solutions to pharmacological investigations. Continued research is focused on its bioavailability, therapeutic potential, and safety profile, with particular emphasis on its dual role as both a beneficial bioactive flavonoid and a modulator of drug pharmacokinetics.

References

Bharti S, Rani N, Krishnamurthy B, and Arya DS (2014) Preclinical evidence for the pharmacological actions of naringin: a review. Planta Medica 80(6) 437–451 DOI: 10.1055/s-0034-1368351

Rouseff RL, Martin SF, and Youtsey CO (1987) Quantitative survey of narirutin, naringin, hesperidin, and neohesperidin in Citrus. Journal of Agricultural and Food Chemistry 35(6) 1027–1030 DOI: 10.1021/jf00078a040

Ting SV (1958) Fruit glycoside hydrolysis: enzymic hydrolysis of naringin in grapefruit. Journal of Agricultural and Food Chemistry 6 546–549 DOI: 10.1021/jf60089a010