Written by Alejandro Andión
INTRODUCTION.
A sweetener is any substance, natural or artificial, that sweetens, it serves to give a sweet taste to a food or product that otherwise has a bitter or unpleasant taste. Among the sweeteners we find those of high caloric value, and those of low caloric value, which are used as substitutes for sugar. In both types we find natural and artificial sweeteners. [1]
Although most of these are of artificial origin, some of them can also be found in nature, in the form of plants. Next, three plants will be described and compared, which have among their sweetener components that can be substitutes for sugar to sweeten food.
1.- STEVIA REBAUDIANA.
Stevia is a species of the genus Stevia of the Asteraceae family native to the tropical region of South America, it is still in the wild in Paraguay, especially in the Department of Amambay, but for several decades it has been cultivated for its sweetening properties and its negligible caloric content. [1]
The shrubs of this species are perennial and reach 0,9 m in height. Its leaves, lanceolate or elliptical and toothed, are alternate, simple, of glossy dark green colour and rough surface, sometimes somewhat hairy, up to 5 cm long by 2 cm wide. Its stems, pubescent and straight, only branch out after the first vegetative cycle, with a tendency to tilt. The roots are mostly superficial, although a thickened section sinks deeper, fibrous, filiform and perennial, are the only part of the plant in which steviosides do not occur. [1]
Stevia rebaudiana extracts are used as a natural sweetener or in dietary supplements for their glycoside content.
The principles of Stevia rebaudiana are due to its natural active components present in the leaves that are Stevioside and rebaudiosides A, B, C, D and E; Dulcoside A, and Steviolbióside. Stevioside has a slight bitter taste and provides 250 to 300 times the sweetness of sugar. [2]
The leaves of the wild Stevia plant contain 0,3% Dulcoside, 0,6% Rebaudioside C, 3,8% Rebaudioside A and 9,1% Stevioside. [2]
According to Sharma et al. (2006) fresh Stevia leaves contain a large amount of water (80 to 85%). Apart from the aforementioned components (glycosides), the leaves contain ascorbic acid, β-carotene, chromium, cobalt, magnesium, iron, potassium, phosphorus, riboflavin, thiamine, stane, zinc, etc. Among the chemicals found are apigenin, austroiniline, avicularin, β-sitosterol, caffeic acid, campesterol, caryophyllene, centaureidin, chlorogenic acid, chlorophyll, kaempferol, luteolin, quercetin, stigmasterol, among others. [2]
2.- GLYCYRRHIZA GLABRA. [1]
Licorice (Glycyrrhiza glabra) also called licorice, orozuz or orosús, is a member of the Fabaceae family native to North Africa, Eastern and Southern Europe and tropical and temperate Asia. It is widely cultivated in many countries, where it has also been naturalized in wetlands, such as riverbeds, ravines, troughs, etc.
The root of this plant is one of the oldest condiments. It has an aniseed and bittersweet taste. It is widely used in confectionery, desserts, cakes, sweets and in drinks. Candies, tablets and wafer strips are also made for sale in pharmacies and candy stands, for their characteristic and pleasant flavor and for their properties to eliminate bad breath. It is an ingredient of odorous pipe tobacco that is characterized by its sweet smell. For its use as a chewing stick, it is also known as paloduz, palo duz, palodú or palodul.
It is a herbaceous perennial with stoloniferous roots reaching 1 m in height, with pinnate leaves about 7 to 15 cm long, composed of 9 to 17 leaflets. The flowers, 8 to 12 cm long, are purple or pale blue, and arise in small inflorescences. The fruit is an oblong legume of about 2 to 3 cm with several seeds. The roots are stoloniferous, that is, they extend horizontally and sprout, thus propagating the plant.
Main components:
• acids: salilic, malic, betulyte, glycyretic
• amino acids: asparagine
• sugars: glycyrrhizin, glucose and sucrose
• beta-carotene
• flavonoids: licoflavonol, licoricone, glycyrolal, glizarin, formononetine, propenylanilosa, isoliquiritigenin, glabrol, glabrona
• minerals: calcium, chromium, cobalt, phosphorus, magnesium, potassium, silicon and sodium
• proteins
• saponina
• tannin
• vitamins: vitamin C and vitamin B1
The aroma of licorice root comes from a complex and variable combination of compounds, of which anethole is up to 3% of the total volatiles. Much of the sweetness of licorice comes from glycyrrhizin, which tastes sweet, 30 to 50 times higher than sugar. Sweetness is very different from sugar, being less instantaneous, sour, and lasting longer.
The form of consumption consists of the root and dried stolons.
3.- SMALLANTHUS SONCHIFOLIUS
The yacon (Smallanthus sonchifolius) is a tuber grown in warm and temperate areas of the Andes Mountains for its crunchy texture and sweet taste.
These plants produce two types of roots: propagation and reserve or storage. Propagation roots grow beneath the soil surface and produce new buds that will become the aerial parts of a new plant. The storage roots are large and edible with tubers that can weigh up to 1 kg. [1]
Yacon plants can grow up to 1,5 to 2 m in height, although on some occasions it can be exceeded; this perennial plant produces small, yellow and inconspicuous flowers at the end of the growing season. Unlike other root vegetables domesticated by the Incas such as olluco or goose, yacon is not sensitive to photoperiods, and can produce a commercial crop in the tropics.
It first arrived in Japan in the 1970s, and from there it spread to other countries in Asia, especially South Korea, China, the Philippines, Taiwan and today it is widely available in their markets. Later, in 1985, he arrived in New Zealand. It grows very well in South Australia (including Tasmania). [1]
The tuber of this plant can enter the group of fruits due to its flavor and properties, it has a composition of 85% water and a wide nutritional chart, contains inulin, calcium, phosphorus, magnesium, potassium, iron, vitamins A and C.
On the other hand, it has fructooligosaccharides that work as natural sweeteners much healthier than the fructose of ordinary fruits, this component creates a protective layer in the stomach that prevents the reproduction of bacteria that harm the body. [3]
Fructooligosaccharides (FOS) have half the calories per gram of sucrose or glucose with a sweetening power relative to sucrose of 0,3-0,6. Inulin is a fructan with a degree of polymerization of 20 to 60 fructose monomers with a known prebiotic effect that is found naturally in this plant (12,5 g / 100 g), and that is historically cultivated in several countries of Latin America. This tuber is mainly consumed as a sweetener and the possibility of a nutraceutical effect has been raised due to the important content of various minerals, vitamin C and vitamins of group B. [4]
COMPARATIVE STUDY
SWEETENER COMPONENTS.
Each of these three plants has different components that make them sweet. Below is cited in each case which component makes each of these plants have a sweet taste.
Stevia rebaudiana: Stevioside and rebaudioside.
Glycyrrhiza glabra: glycyrrhirin.
Smallanthus sonchifolius: fructooligosaccharides and inulin.
SWEETENING POWER.
Although these three plantains have sweetening compounds, not all of them have the same sweetness or sweetening power, a quantitative comparison of the sweetening power of each plant is shown here below.
Stevia rabaudiana: of these three plants it is the one that has the greatest sweetening power with 250-300 times the sweetness of sugar.
Glycyrrhiza glabra: licorice root ranks second with 30-50 times the sweetness of sugar.
Smallanthus sonchifloius: yacon is the one with the least sweetening power, the only one that is less sweet than common sugar, with 0,3-0,6 times the sweetness of sugar.
BENEFITS FOR THE BODY.
Below will be cited some benefits for the body of these plants.
3.- STEVIA REBAUDIANA. [5]
DIABETES
A study published in Science Direct showed that stevia sweeteners did not add calories or carbohydrates to the diet and did not affect blood glucose levels or insulin response, allowing people with diabetes to consume a greater variety of foods. In addition, a paper on nutritive and non-nutritive sweeteners from the Academy of Nutrition and Dietetics examined five randomized controlled trials about the effects of stevia compared to placebos on metabolic outcomes, concluding that its effect was minimal on blood glucose levels, insulin levels, hypertension, and body weight.
WEIGHT CONTROL
The causes of overweight and obesity are multifactorial, that is, they are due to a wide range of possibilities, including physical inactivity, prolonged sedentary lifestyle and a higher intake of foods rich in fat and added sugars. Medicine has shown that the intake of added sugars contributes an average of 16% of total calories in the diet and has been linked to weight gain and adverse effects on glycemic control. Therefore, stevia, which is a product made from plants, without calories, can be part of a well-balanced diet to help reduce calorie intake without sacrificing flavor.
BLOOD PRESSURE
Certain glycosides in stevia extract dilate blood vessels, increase sodium excretion and urine production. At higher doses, stevia could potentially help lower blood pressure. The intake of stevia can therefore normalize blood pressure and regulate the heartbeat.
Health regulatory agencies around the world have approved high-purity stevia leaf extracts as completely safe consumption. This includes special populations such as pregnant and lactating women, children, and people with allergies or diabetes.
2.- GLYCYRRHIZA GLABRA. [6]
ANTI-ULCER EFFECT
Within its pharmacological activity, the peptic anti-ulcer and protective effect of the gastric mucosa stands out. This effect is mainly due to saponosides, although not exclusively, since other active ingredients, such as flavonoids, are also involved.
There are numerous clinical studies that show that licorice extract, on the one hand, reduces gastric secretions, thereby preventing the formation of ulcers, and on the other, glycyrrhetic acid acts by inhibiting a number of enzymes of the group of dehydrogenases and reductases, which translates into an increase in the values of prostaglandins and, consequently, an increase in the secretion of mucus, of protective effect, and of the cellular proliferation of the gastric mucosa, which favors the healing and regeneration of damaged tissues.
Likewise, different in vitro pharmacological tests confirm the bactericidal efficacy of licorice extracts and their active components against Helicobacter pylori, so this effect can also contribute to the improvement.
EXPECTORANT AND ANTITUSSIVE ACTIVITY
The roots and rhizomes of Glycyrrhiza glabra possess demulcent, antitussive and expectorant properties that facilitate the expulsion of bronchial secretions in conditions of the upper respiratory tract.
ANTI-INFLAMMATORY AND ANTIPLATELET ACTIVITY
Its anti-inflammatory activity could be due to the ability of some active ingredients of this drug, such as glycyrrhirin and isouchiritogenoside, to inhibit enzymes involved in the arachidonic acid cascade, such as cyclooxygenase, lipoxygenase, and platelet peroxidase, so they also inhibit the formation of eicosanoids such as PGE2 and thromboxane B2. For this reason, it also exerts an antiplatelet effect.
Moreover, 18-betaglyrrhetinic acid inhibits the production of interleukin-8 (IL-8), which is another pro-inflammatory mediator.
ANTIOXIDANT EFFECT
Its antioxidant and free radical scavenging capacity is of special importance, as it can contribute positively to many of its pharmacological activities. Many of its components, mainly flavonoids and saponosides, act as potent antioxidants. Among many other studies conducted on this ability, it has been shown in in vitro assays in rat hepatocytes that some isoflavonoids such as hispaglabridine A and B inhibit mitochondrial lipid peroxidation induced by Fe3+. Likewise, it has been seen that glabridin, as well as glycyrrhizin, have the ability to inhibit the generation of reactive oxygen species in neutrophils during the inflammatory process. Likewise, it has been found in models of ischemia reperfusion that glycyrrhizin significantly decreases hepatic lipid peroxidation.
ANTIVIRAL ACTION
As for its antiviral effects, it has been demonstrated, in vitro and in vivo, that glycyrrhinic acid can prevent the replication of both DNA and RNA viruses, such as varicella zoster virus (VZV), human immunodeficiency virus (HIV), Influenza A and B, herpes simplex (HSV) 1 and 2, hepatitis A and C, without toxicity of the cell lines used in the different tests carried out. Glycyrrhizinic acid decreases the replication of viruses at an early stage; it also prevents the exit of the virion from its capsid and with this its penetration into the cells.
ANTICANCER ACTIVITY
Some components of licorice, such as glycyrrhizin, possess anticancer properties, as they have been shown to have the ability to inhibit cell proliferation, carcinogenesis, and tumor growth in models of breast, liver, and skin cancer. Likewise, it has been found that an extract of licorice, as well as its active ingredient liquiritigenin, have a cytoprotective effect against cadmium-induced apoptosis. However, it is still necessary to have more studies, both in animals and humans, to establish its therapeutic application in this field.
People who habitually consume laxative preparations or licorice-based candies are more exposed, in an unconscious way, to the appearance of side effects
3.- SMALLANTHUS SONCHIFOLIUS. [7]
REGULATE INTESTINAL TRANSIT
Yacon is a tuber rich in fructans, mainly inulin and fructooligosaccharides (FOS), these compounds can resist gastric juices, passing through the digestive tract without being metabolized, being considered as a prebiotic food.
Prebiotics favor the increase of bifidobacteria of the colon, increase bowel movements and the volume of feces, being an excellent option to combat constipation.
CONTROL BLOOD SUGAR
The FOS content of yacon promotes the absorption of glucose in peripheral tissues, improving insulin sensitivity in the liver and increasing insulin secretion by the pancreas, thus favoring the decrease in glycemia, being an option for people suffering from prediabetes and diabetes.
Reduce cholesterol and triglycerides
Yacon helps reduce cholesterol and triglycerides because it contains polyphenols and the presence of FOS, which could help regulate fat metabolism in the body and suppress triglyceride synthesis in the liver.
REDUCE CHOLESTEROL AND TRIGLYCERIDES
Yacon helps reduce cholesterol and triglycerides because it contains polyphenols and the presence of FOS, which could help regulate fat metabolism in the body and suppress triglyceride synthesis in the liver.
1. Wikipedia, La enciclopedia libre.
2. Samuel Durán A., María del Pilar Rodríguez N., Karla Cordón A., Jiniva Rcord C. . (December, 2012). Stevia (Stevia rebaudiana), edulcorante no calórico (Stevia rebaudiana), non-caloric natural sweetener).
https://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-75182012000400015#:~:text=El%20Estevi%C3%B3sido%20tiene%20un%20ligero,Estevia%20a%C3%BAn%20no%20est%C3%A1%20disponible.
3. CVN. (November 8, 2018). El universo del yacón.
https://www.cvn.com.co/admincvn/el-universo-del-yacon/#:~:text=El%20yac%C3%B3n%20es%20un%20tub%C3%A9rculo%20que%20puede%20entrar%20en%20el,hierro%2C%20vitaminas%20A%20y%20C.
4. J. M. García-Almeida, Gracia M. ª Casado Fdez. and J. García Alemán. (July, 2013). Una visión global y actual de los edulcorantes. Aspectos normativos (A current and global review of sweeteners. Regulatory aspects).
https://scielo.isciii.es/scielo.php?script=sci_arttext&pid=S0212-16112013001000003
5. Sarah Romero. (July 10, 2017). Beneficios de la estevia para la salud.
https://www.muyinteresante.es/salud/fotos/beneficios-de-la-estevia
6. M Transit Lopez Then. (January, 2008). El regaliz, Actividad farmacológica, indicaciones y consejos para su uso.
https://www.elsevier.es/es-revista-offarm-4-articulo-el-regaliz-actividad-farmacologica-indicaciones-13114933
7. Tatiana Zanin. (March, 2022). Yacón: para qué sirve y cómo prepararlo.
https://www.tuasaude.com/es/yacon/