Types of Terpenes

Monoterpenes, sesquiterpenes, and MORE! Understanding types of terpenes is essential when it comes to YOUR products.

We get it, terpenes are tricky. Luckily, they don’t have to be! Read on to learn about different types of terpenes.

Even if you already know a bit about terpenes, deep-diving into the different types of terpenes is surprisingly helpful. If this is ALL new to you, however, here’s the world’s quickest rundown - terpenes are the natural hydrocarbons present in the essential oils of most plants. On top of their evolutionary functions, like defense (1), they’re what dictate the unique aroma and flavor of different plants. But there’s a lot more to it than that…

Your average consumer MIGHT know that information, but they’re probably less aware of the different types of terpenes. That’s right! There are several different types of terpenes grouped together depending on the number of units required to form a molecule. 

But what does this have to do with you and your products? Everything! Read on and learn about different types of terpenes and why that matters for your products.

Reading Time - 5.5 min

Are you on the edge of your seat for this information? We can’t blame you. Here’s a brief overview of what we’re covering today:

• Monoterpenes have two isoprene units and are divided into acyclic, monocyclic, and bicyclic terpenes. Common monoterpenes include Myrcene, Linalool, Limonene, etc.
• Sesquiterpenes are comprised of three isoprene units and are also categorized similarly to monoterpenes. Common sesquiterpenes include Alpha-humulene, Beta-caryophyllene, Farnesol, etc.
• Diterpenes have four isoprene units and two of them, cafestol and kahweol, are plentiful in coffee beans. 
• Triterpenes are made from six isoprene units and can oxidize into alcohols, aldehydes, and carboxylic acids.
• There are also hemiterpenes, tetraterpenes, polyterpenes, and MORE! Honestly, it would require several degrees and years of study to learn all there is to know about terpenes. That’s probably why we’re so insanely proud of our “terpene experts.”

What Are Monoterpenes?

Monoterpenes are those with ten carbon atoms and two isoprene units. 

(C10H16)      

This group is divided even further into acyclic, monocyclic, and bicyclic terpenes. “Within each group, the monoterpenoids may be simple unsaturated hydrocarbons or may have functional groups and be alcohols, aldehydes, and ketones” (2). Oftentimes, these are the terpenes with strong, distinctive aromas and flavors. For example, the following terpenes are considered monoterpenes:

• Myrcene 
• Citral 
• Linalool 
• α-terpineol
• Limonene 
• Menthol 
• α-pinene 
• Camphor

On top of their flavor and aroma, these terpenes have other important properties. “Most of the monoterpenes are active biologically with strong antibacterial activities. Several studies have shown in vitro and in vivo antitumor activity of many essential oils obtained from plants. The antitumor activity of essential oils of many species has been related to the presence of monoterpenes in their composition” (3).

For example, monoterpenes have been known to “...prevent the carcinogenesis process at both the initiation and promotion/progression stages. In addition, monoterpenes are effective in treating early and advanced cancers.” Specifically, Limonene and perillyl alcohol have been observed for their efficacy in preventing mammary, liver, lung, and other cancers. Results look particularly promising and both “are currently being evaluated in phase I clinical trials in advanced cancer patients” (4).

What Are Sesquiterpenes?

Sesquiterpenes have three isoprene units and are divided into linear, cyclic, bycyclic, and tricyclic categories.

(C15H24)

Additionally, “sesquiterpenes are also found in the form of lactone ring. Many of the latex in latex-producing plants contain sesquiterpene, and these are potent antimicrobial and anti-insecticidal agent” (5). The following are considered sesquiterpenes:

• α-Humulene 
• β-Caryophyllene 
• α-bisabolol
• Farnesol 
• Valencene

Like monoterpenes, sesquiterpenes have a surprisingly long list of properties that are being investigated as we speak. According to a review by the International Journal of Molecular Sciences, “Sesquiterpenoids, and specifically sesquiterpene lactones from Asteraceae, may play a highly significant role in human health, both as part of a balanced diet and as pharmaceutical agents, due to their potential for the treatment of cardiovascular disease and cancer.” Various sesquiterpenes have been linked to properties like reduced inflammation, reduced tumorigenesis, antimicrobial properties, and more (6). 

Anti-inflammatory properties, in particular, have been studied quite extensively. For example, “Farnesol… is an acyclic sesquiterpene alcohol present in many essential oils, such as citronella, lemongrass and rose, and known to work as a chemopreventative, anti-tumor and anti-inflammatory agent.” Additionally, “Bisabolol has been shown to exhibit anti-irritant, anti-inflammatory and anti-microbial activities, and is used in various fragrances and in cosmetics because of its skin healing properties (7).

What Are Diterpenes?

Diterpenes have four isoprene units and “This class of compounds showed significant biological activities including anti-inflammatory, antimicrobial, anticancer, and antifungal activities. Some of the diterpenes also have cardiovascular activity, such as grayanotoxin, forskolin, elagonolone, marrubenol, and 14-deoxyandrographolide” (8). 

(C20H32)

If you’re having a hard time picturing this group, we have one word for you - coffee. Yes, some of the aromatic compounds found in the beloved coffee bean are actually diterpenes. Specifically, coffee is rich in the diterpenes “...cafestol and kahweol, which are predominantly present in the esterified form with different fatty acids” (9). 

It’s important to note, however, that cafestol and kahweol may influence cholesterol. According to the Institute for Scientific Information on Coffee (yes, that actually exists), “Research suggests that high consumption of these compounds can raise serum levels of total and LDL cholesterol” (10). They do specify, however, that cholesterol impact is affected by brewing method. These particular diterpenes are often trapped in a coffee filter. So, coffee made without a filter will have more of these compounds.

Triterpene, Tetraterpenes, and MORE

But what about hemiterpenes? Tetraterpenes? Polyterpenes? That’s right, there are even MORE terpenes! 

Triterpenes (made from six isoprene units) are unlike other terpenes because they “...can be oxidized into alcohols, aldehydes, and carboxylic acids, which make it complex and differentiate it biologically.” There have been several studies examining the efficacy of triterpenes when it comes to immunity (11).

Squalene, for example, is a triterpene often used in the cosmetic industry because of its moisturizing properties. On top of that, “...squalene is extensively used as an excipient in pharmaceutical formulations for disease management and therapy. In addition, squalene acts as a protective agent and has been shown to decrease chemotherapy-induced side-effects” (12).

There are also tetraterpenes, hemiterpenes, polyterpenes, etc. Honestly, it would require several degrees and years of study to learn all there is to know about terpenes. That’s probably why we’re so insanely proud of our “terpene experts.”

WHY Types of Terpenes Matter

If you couldn’t tell already, the different types of terpenes matter for several reasons. First, some are all about aroma and flavor. Obviously, you want your products to smell and/or taste good! Second, certain types of terpenes have beneficial properties that could be invaluable for the effectiveness of your products! 

We would love nothing more than to discuss terpenes all day, so contact us today if you have any questions about adding terpenes to your products. 

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