**1. Introduction**

#### **1.1 Characteristics of the genre**

The genus *Capsicum* belongs to the Solanaceae family, which consist of different variants of peppers that can be easily recognized by their size, shape, color and degree of pungency. This latter characteristic allows the classification of chili peppers depending on their Scoville heat units (SHU), a measurement of their pungency, into spicy or hot foods (generally those with small fruits) and sweet or

non-pungent (generally those with large fruits). This aspect is very interesting for marketing them and makes them a demanded product [1]. Considering this, we can consider for example the pungency of paprika peppers (10–30 parts per million capsaicinoids), chili peppers (30–600 parts per million) and red peppers (600– 13,000 parts per million) [2]. Ripe fruits display a range of colors varying from white to deep red. Likewise, the intensity of red color and the degree of pungency are valued as major quality parameters. That is why the fruit is harvested when its red color has completely developed in order to ensure the highest quality of these features [3].

*Capsicum* is a very homogeneous genus with 33 species and 10 varieties (**Table 1**), with only five of them being domesticated: *Capsicum baccatum* L., *Capsicum pubescens* Ruiz & Pav., *Capsicum frutescens* L., *Capsicum chinense* Jacq. and *Capsicum. annuum* L. (**Figure 1**) native to Central and South America [5]. Each one of them was farmed independently in Pre-Columbians times in diverse regions of the American tropics [4]. They have been genetically modified to obtain varieties with agronomic interests, as in the case of *C. annuum* L. in which varieties more resistant to adverse factors were created, with a higher content and/or yield of the compounds of interest and fruit quality [6].

Amid the species *C. annuum*, there are different well know varieties like paprika, cayenne, jalapeños or chiltepin. Inside the specie *C. frutescens* are tabasco chilis; among *C. chinense*, the hottest chills (naga, habanero and Scotch bonnet) and among *C. pubescens* and *C. baccatum*, peppers emblematic from South America like rocoto or aji [7].

Although the characteristics of each species differ from each other (**Table 2**), it can be said that the genus *Capsicum* is characterized by being an annual or perennial herb or undershrub with entire or repand leaves that alternate. Its flowers are pedicelled, enclosing five petals; it is axillary and can appear solitary or in groups of two or three. Its sepals connate in a subentire or minutely five-toothed calyx that is much shorter than the fruit. It also has 5 stamens, which are adnate nearly to base of corolla-tube and are characterized for being short filaments. Its carpels connate in a two-celled (in some cases three) ovary, and its anthers are dehiscence longitudinal


without any exceeding filaments. As for fruit and seeds, the first is irregularly shaped (globose or elongate) with many seeded berries. Seeds are discoid, smooth

*Characteristics that allow to distinguish between the most common species of the* Capsicum *genus [8].*

*Some of the major cultivated pepper species. (A)* Capsicum frutescens*; (B)* Capsicum annuum*;*

Capsicum *Seeds as a Source of Bioactive Compounds: Biological Properties…*

*DOI: http://dx.doi.org/10.5772/intechopen.91785*

**Species Flower color N° flower Seed color Calyx constriction Distribution** *C. annuum* White 1 Tan Absent Colombia, USA *C. frutescens* Green 2–5 Tan Absent No studies *C. chinese* White-green 2–5 Tan Present South America *C. baccatum* White with yellow spot 1–2 Tan Absent South America *C. pubescens* Purple 1–2 Black Absent South America

*(C)* Capsicum chinense*, and (D)* Capsicum baccatum*.*

*Capsicum annuum* is an annual cultivate that reaches a height of 1 m and has glabrous or pubescent lanceolate leaves, white flowers, and fruit of varying length, color, and pungency depending upon the cultivar and growth conditions. It also the most widely cultivated pepper species around the world. Considering another species, *Capsicum frutescens* is a short-lived perennial with woody stems that reach

Thus, its physical appearance defers from one species to another. For example,

or subscabrous [8].

**Figure 1.**

**Table 2.**

**125**

#### **Table 1.**

*Taxonomic classification of the genus* Capsicum *[1, 4].*

Capsicum *Seeds as a Source of Bioactive Compounds: Biological Properties… DOI: http://dx.doi.org/10.5772/intechopen.91785*

#### **Figure 1.**

non-pungent (generally those with large fruits). This aspect is very interesting for marketing them and makes them a demanded product [1]. Considering this, we can consider for example the pungency of paprika peppers (10–30 parts per million capsaicinoids), chili peppers (30–600 parts per million) and red peppers (600– 13,000 parts per million) [2]. Ripe fruits display a range of colors varying from white to deep red. Likewise, the intensity of red color and the degree of pungency are valued as major quality parameters. That is why the fruit is harvested when its red color has completely developed in order to ensure the highest quality of these

*Capsicum* is a very homogeneous genus with 33 species and 10 varieties (**Table 1**), with only five of them being domesticated: *Capsicum baccatum* L., *Capsicum pubescens* Ruiz & Pav., *Capsicum frutescens* L., *Capsicum chinense* Jacq. and *Capsicum. annuum* L. (**Figure 1**) native to Central and South America [5]. Each one of them was farmed independently in Pre-Columbians times in diverse regions of the American tropics [4]. They have been genetically modified to obtain varieties with agronomic interests, as in the case of *C. annuum* L. in which varieties more resistant to adverse factors were created, with a higher content and/or yield of the

Amid the species *C. annuum*, there are different well know varieties like paprika, cayenne, jalapeños or chiltepin. Inside the specie *C. frutescens* are tabasco chilis; among *C. chinense*, the hottest chills (naga, habanero and Scotch bonnet) and among *C. pubescens* and *C. baccatum*, peppers emblematic from South America like

Species *C. baccatum*, *C. pubescens*, *C. frutescens*, *C. chinense*, *C. annuum*

Varieties *C. annuum* var*. annuum*, *C. annuum* var*. glabriusculum*, *C. baccatum* var*. pendulum*

Although the characteristics of each species differ from each other (**Table 2**), it can be said that the genus *Capsicum* is characterized by being an annual or perennial herb or undershrub with entire or repand leaves that alternate. Its flowers are pedicelled, enclosing five petals; it is axillary and can appear solitary or in groups of two or three. Its sepals connate in a subentire or minutely five-toothed calyx that is much shorter than the fruit. It also has 5 stamens, which are adnate nearly to base of corolla-tube and are characterized for being short filaments. Its carpels connate in a two-celled (in some cases three) ovary, and its anthers are dehiscence longitudinal

features [3].

Capsicum

rocoto or aji [7].

**Kingdom Plantae**

Subclass Asteridae Order Solanales Family Solanaceae Genus *Capsicum*

*Taxonomic classification of the genus* Capsicum *[1, 4].*

**Table 1.**

**124**

Subkingdom Tracheobionta Division Magnoliophyta Class Magnoliopsida

compounds of interest and fruit quality [6].

*Some of the major cultivated pepper species. (A)* Capsicum frutescens*; (B)* Capsicum annuum*; (C)* Capsicum chinense*, and (D)* Capsicum baccatum*.*


#### **Table 2.**

*Characteristics that allow to distinguish between the most common species of the* Capsicum *genus [8].*

without any exceeding filaments. As for fruit and seeds, the first is irregularly shaped (globose or elongate) with many seeded berries. Seeds are discoid, smooth or subscabrous [8].

Thus, its physical appearance defers from one species to another. For example, *Capsicum annuum* is an annual cultivate that reaches a height of 1 m and has glabrous or pubescent lanceolate leaves, white flowers, and fruit of varying length, color, and pungency depending upon the cultivar and growth conditions. It also the most widely cultivated pepper species around the world. Considering another species, *Capsicum frutescens* is a short-lived perennial with woody stems that reach

a height of 2 m, with glabrous or pubescent leaves, with two or more greenish-white flowers per node, and extremely pungent fruit [2].

**Common name State Carbohydrates Protein Fat Capsaicinoids Fiber Ash** Guajillo D 58.00 12.89 12.43 5.97 Nd 7.52 Ancho D 60.21 12.05 9.82 8.50 Nd 7.81 Pasado D 66.18 12.61 5.41 9.74 Nd 7.18 Pasilla D 60.53 12.28 13.76 11.80 Nd 5.85 Puya D 63.76 13.25 8.11 12.13 Nd 7.82 M. Tres venas D 61.05 13.28 9.61 14.40 Nd 7.02 Chiplote Meco D 57.68 15.22 9.08 29.01 Nd 9.54 Jalapeno D 63.97 14.36 4.23 58.40 Nd 7.32 Mirasol D 58.96 14.05 7.49 58.55 Nd 9.61 Morita D 58.91 14.12 7.60 67.32 Nd 8.59 Serrano D 67.93 12.78 2.26 102.73 Nd 5.81 Chiplote D 62.92 12.72 8.66 143.57 Nd 6.92 De Arbol D 59.41 12.75 13.38 193.51 Nd 8.82 Piquin D 62.25 13.72 11.02 368.83 Nd 7.28 Habanero D 61.13 13.52 4.63 1312.10 Nd 7.51 Marako fana D 35.3 11.8 11.2 Nd 27.3 5.3 Bako local D 39.5 8.7 9.5 Nd 26.0 7.3 Oda haro D 37.1 9.2 9.2 Nd 28.6 7.3 Arnoia red F 6.23 0.15 0.54 Nd 1.62 0.62 Arnoia green F 3.84 0.14 0.22 Nd 1.63 0.40 Arnoia green B F 3.51 0.12 0.16 Nd 1.31 0.33 Hot pepper D Nd 21.29 23.65 Nd 38.76 4.94 Chunhamuchuk D Nd 15.05 29.27 Nd 48.72 3.59 Amhanegosa D Nd 14.66 26.70 Nd 52.10 3.28 Hanbando D Nd 14.08 27.84 Nd 38.43 3.49 Dachon I D Nd 15.99 19.53 Nd 50.61 3.76 Samgang D Nd 13.90 23.50 Nd 50.71 3.71 Chunhajeil D Nd 14.67 21.87 Nd 52.54 3.46 Daejangbu D Nd 14.88 26.50 Nd 53.78 3.47 Hongjangkun D Nd 15.17 21.61 Nd 54.66 3.33 Kumbit D Nd 15.09 23.28 Nd 46.17 3.18 Dokyachungjung D Nd 15.75 25.13 Nd 53.36 3.86 Dangchan D Nd 15.36 19.99 Nd 55.63 3.46 Chohyang D Nd 13.25 18.05 Nd 59.13 3.77 Taesan D Nd 14.71 23.45 Nd 48.80 3.11 Ganggun D Nd 15.55 20.63 Nd 52.71 3.43 Chungsan D Nd 15.06 20.45 Nd 50.75 3.05 Dachon II D Nd 15.89 18.83 Nd 45.73 3.61 Wangdaebak D Nd 16.53 23.65 Nd 54.39 3.28 Chunhailpum D Nd 15.70 19.79 Nd 53.34 3.38

Capsicum *Seeds as a Source of Bioactive Compounds: Biological Properties…*

*DOI: http://dx.doi.org/10.5772/intechopen.91785*

**127**

Being a cold sensitive plant, the best conditions for production are between 7 and 29°C and an annual precipitation of 0.3–4.6 mm. It grows best in well-drained, sandy or silt-loam soil and a soil pH of 4.3–8.7. Hot and dry weather is also desirable for fruit ripening [2]. To carry out its cultivation it is necessary to seed or transplant the peppers, harvesting 3 months after planting [2].

#### **1.2** *Capsicum* **seeds sources and production**

Chili (a variety of *C. annuum*) is one of the first plants cultivated in Mesoamerica, existing evidence of its use for the last 9000 years. It can be used in multiple ways: fresh, dry, as a spice powder, natural dye, antioxidant, bactericide and fungicide, as a drug in the pharmaceutical industry, in the cosmetology industry or in food industry (sausage, canned meats) [9]. These characteristics made them an essential part of daily cooking in many Latin American and Asian countries, for example, curry blends in India or in many meat sausages both fresh and dehydrated in the Mediterranean region [3].

On the basis of extracts obtained from pre-ceramic in the Coxcatlan caves, it is believed that the domestication of *C. annuum* probably occurred in the northeast or central-east of Mexico, being older than the remains of corn, beans and pumpkin [1]. In fact, peppers presently represent one of the vegetables of greater economic importance just behind the tomato for several American tropical countries [10].

Of the five domesticated species of *Capsicum* spp., the largest cultivated and with higher production per hectare are *C. annuum* and *C. frutescens* [11]*.* As for its world production, it is estimated that it is nearby 24.9 million tons (*C. annuum*), making it the ninth most produced vegetable in the world. Likewise, it has had an annual average growth of 6.26% in the last 10 years, with Mexico being its main consumer with an annual average of 8 kg/person. Its main producers are China (60.6%), Turkey (8.4%), Mexico (7.8%), Spain (5.0%), USA (4.3%), Indonesia (3.4%), Nigeria (2.8%), Egypt (2.2%), Korea (2.0%) and Italy (1.7%) [7]. In Mexico, one of the countries with the highest production levels, there are about a hundred cultivars of hot *Capsicum* spp. with varying degrees of spiciness, size, shape and colors. Nonetheless, there are also varieties that are cultivated throughout the world. This is the case of *C. annuum* or *C. chinense* [12]. Hence, it is a product that is traded internationally. This means that a series of elements such as aflatoxins, pesticides, residuals, microbial contaminations or infections, capsaicin levels and color values are subjected to inspection. All these aspects are controlled by law in several countries (EU, USA) [8].

Pepper quality depends on their composition, which is determined by factors such as environmental cultivation conditions, variety, ripeness, and pre-harvest and post-harvest handling and preservation [13]. The degree of ripening required may be one of the most important factors in quality, but it will also depend on the destined market, since not the same degree of maturity is desired for all the possible uses. Notably, the moment of harvesting is also important for the maintenance of the quality as metabolic activity persists after harvesting [14].

#### **1.3 Chemical composition**

Regardless of the enormous consumption and production of this kind of vegetables, there is little data about the chemical composition of the different varieties (**Table 3**). However, the demand and cultivation of peppers, especially "hot" cultivars, has increased due to its flavoring and medicinal properties. Some of the latter have been described as anticancer, antioxidant and antimicrobial. Its edible and


Capsicum *Seeds as a Source of Bioactive Compounds: Biological Properties… DOI: http://dx.doi.org/10.5772/intechopen.91785*

a height of 2 m, with glabrous or pubescent leaves, with two or more greenish-white

Being a cold sensitive plant, the best conditions for production are between 7 and 29°C and an annual precipitation of 0.3–4.6 mm. It grows best in well-drained, sandy or silt-loam soil and a soil pH of 4.3–8.7. Hot and dry weather is also desirable for fruit ripening [2]. To carry out its cultivation it is necessary to seed or transplant

Chili (a variety of *C. annuum*) is one of the first plants cultivated in Mesoamerica, existing evidence of its use for the last 9000 years. It can be used in multiple ways: fresh, dry, as a spice powder, natural dye, antioxidant, bactericide and fungicide, as a drug in the pharmaceutical industry, in the cosmetology industry or in food industry (sausage, canned meats) [9]. These characteristics made them an essential part of daily cooking in many Latin American and Asian countries, for example, curry blends in India or in many meat sausages both fresh and dehydrated in the Mediterranean region [3].

On the basis of extracts obtained from pre-ceramic in the Coxcatlan caves, it is believed that the domestication of *C. annuum* probably occurred in the northeast or central-east of Mexico, being older than the remains of corn, beans and pumpkin [1]. In fact, peppers presently represent one of the vegetables of greater economic importance just behind the tomato for several American tropical countries [10]. Of the five domesticated species of *Capsicum* spp., the largest cultivated and with higher production per hectare are *C. annuum* and *C. frutescens* [11]*.* As for its world production, it is estimated that it is nearby 24.9 million tons (*C. annuum*), making it the ninth most produced vegetable in the world. Likewise, it has had an annual average growth of 6.26% in the last 10 years, with Mexico being its main consumer with an annual average of 8 kg/person. Its main producers are China (60.6%), Turkey (8.4%), Mexico (7.8%), Spain (5.0%), USA (4.3%), Indonesia (3.4%), Nigeria (2.8%), Egypt (2.2%), Korea (2.0%) and Italy (1.7%) [7]. In Mexico, one of the countries with the highest production levels, there are about a hundred cultivars of hot *Capsicum* spp. with varying degrees of spiciness, size, shape and colors. Nonetheless, there are also varieties that are cultivated throughout the world. This is the case of *C. annuum* or *C. chinense* [12]. Hence, it is a product that is traded internationally. This means that a series of elements such as aflatoxins, pesticides, residuals, microbial contaminations or infections, capsaicin levels and color values are subjected to inspection. All these aspects are controlled by law

Pepper quality depends on their composition, which is determined by factors such as environmental cultivation conditions, variety, ripeness, and pre-harvest and post-harvest handling and preservation [13]. The degree of ripening required may be one of the most important factors in quality, but it will also depend on the destined market, since not the same degree of maturity is desired for all the possible uses. Notably, the moment of harvesting is also important for the maintenance of

Regardless of the enormous consumption and production of this kind of vegetables, there is little data about the chemical composition of the different varieties (**Table 3**). However, the demand and cultivation of peppers, especially "hot" cultivars, has increased due to its flavoring and medicinal properties. Some of the latter have been described as anticancer, antioxidant and antimicrobial. Its edible and

the quality as metabolic activity persists after harvesting [14].

flowers per node, and extremely pungent fruit [2].

Capsicum

the peppers, harvesting 3 months after planting [2].

**1.2** *Capsicum* **seeds sources and production**

in several countries (EU, USA) [8].

**1.3 Chemical composition**

**126**


of fresh product, respectively). Other vitamins that can be found in peppers are thiamine, riboflavin, niacin and pyridoxine. Moreover, jalapeños also contain important amino acids such as lysine, methionine and valine (252, 40 and 23 mg per

Like many fruits and plants, peppers are an excellent nutritional source. As aforementioned, it has an abundance of minerals, vitamins, aminoacids, carotenoids as also phytochemicals like phenolic compounds or polyunsaturated fatty acids (PUFAs). Likewise, capsaicins are unique to the genus *Capsicum*, being responsible of the pungency of many pepper species. Capsaicinoids have demonstrated to induce a vast range of bioactivities, such as anti-inflammatory, anticancer analgesic, antimicrobial, hypotensive and induce lower adipogenesis or lower body tempera-

Different bioactive compounds have been isolated and extracted from *Capsicum* spp. fruits and seeds and its concentrations vary among species. More information

Phenolic compounds, also referred as phenolics, are secondary metabolites that may be found in a wide spectrum of plant species. They are synthesized as a result of adaptation to biotic and abiotic stress through the phenylpropanoid pathway playing an important role in plant development, because they act as a defensive mechanism that eases plant growth against harsh conditions [33, 34]. Based on recorded knowledge, phenolic compounds exhibit numerous potential health benefits that are already well described in scientific literature and are currently a major current focus of nutritional and pharmacological research [35, 36]. Phenolic acids and flavonoids are the main phenolic phytochemicals found in peppers. Likewise, capsaicinoids are synthetized in the same biochemical pathway and exhibit some

The yield of phenolic compounds recovered from an extraction can be very different, depending largely on the extraction method, the conservation of vegetal material and maturity state [37]. Generally, fresh raw material preserves the highest quantities of phenolic compounds [16]. Several factors contribute to yielding disparity, such as heterogeneous genotypes, growing and harvesting conditions of the samples [38]. Some of the most prominent non-capsaicinoid phenolic compounds because of their valuable health benefits are phenolic acids like gallic acid, caffeic acid, chlorogenic acid or ellagic acid (**Figure 2**). Flavones are another important group of phenolic compounds, being some of the most prominent kaempferol, quercetin, luteolin or rutin (**Figure 3**) [26]. These phenolics have demonstrated great health benefits and many of them are commercially available in purified products extracted from other plant species [39, 40]. Even so, their concentration differs among species but not much among varieties [26]. Other phenolic compounds are reviewed in the next paragraphs as in the case of some carotenoids or vitamins.

Regarding capsaicinois, they are synthesized naturally in the placenta of pepper fruits by enzymatic transformation of vanillylamine, the phenolic portion of the molecule, which confers this alkaloid its antioxidant capacity [41]. The seeds are not the primary source of capsaicinoids but they may absorb them because they are in close proximity to the placenta, which is the richest capsaicin fraction [42]. Their presence in the seed and the high concentrations they achieve, has been observed to

**2.** *Capsicum* **seeds as a source of bioactive compounds**

Capsicum *Seeds as a Source of Bioactive Compounds: Biological Properties…*

ture by isolated action or in synergy with other compounds [21–25].

on reported compounds studied may be found in (**Table 4**).

similar properties such as antioxidative activity [34].

100 g of protein, respectively) [7].

*DOI: http://dx.doi.org/10.5772/intechopen.91785*

**2.1 Phenolic compounds**

**129**

#### **Table 3.**

*Different* Capsicum *spp. and their proximate chemical composition (g/100 g) [14–18].*

nutritional value is acknowledge as well, since it is rich in vitamins (A, C, B6, E), carotenoids (β-carotene), flavonoids, oils, oleoresins and alkaloids [19]. Therefore, the compounds that can be found in this genre are carbohydrates (accounting for approximately 85% of dry weight), polyphenols (0.5% of dry weight) and important molecules such as capsaicinoids, carotenoids and vitamins [20]. Given these facts, peppers are considered a good source of most essential nutrients [14].

The capsaicinoids content, which depends on the variety and maturation stage, will determinate the pungency. *C. chinense* and *Capsicum annuum* var. *aviculare* contain larger amounts of capsaicin and dihydrocapsaicin (ratio of 2:1), while some varieties of *Capsicum annuum* var*. annuum* showed an average proportion of 1:1. These variations could be attributed to environment, genetics and extraction methodologies [15]. Even though in some cases peppers are sought to be spicy, this can also be a limitation. This is the case, for example, in obtaining dyes from this raw material in the food industry. In this case, extraction methods need to be improved to prepare non-pungent oleoresins from pungent *Capsicum* fruits. This is achieved by the selective removal of capsaicinoids which allows the exploration of a large number of pungent varieties with good oleoresin yielding [20].

Capsaicinoids are the characteristic pungent compounds of the *Capsicum* genus. They include capsaicin, dihydrocapsaicin, nordihydrocapsaicin, homocapsaicin, and homodihydrocapsaicin. Capsaicin is the most abundant. As an example, capsaicin constitutes together with dihydrocapsaicin approximately 90% of total capsaicinoids content of chili peppers [15].

The characteristic red color of many peppers is determined by the presence of different carotenoids. Actually, more than 50 different carotenoids can be found in this kind of material. Some of them are capsanthin, capsorubin, and cryptocapsin which give brilliant red color (ripe fruits) or β-carotene, violaxanthin, zeaxanthin and β-cryptoxanthin which give yellow–orange color [3]. Nevertheless, the color will depend on the state of maturity. For example, jalapeño (*C. annuum*) has a green color, and when it is mature it presents an intense red color [7]. Therefore, depending on the degree of maturity, the physicochemical parameters, flavor and mineral composition differs. For example, fat, protein, ascorbic acid (vitamin C), soluble solid content and titratable acidity will increase during ripening [14].

Using jalapeño as an example to study composition, its main component is water, then carbohydrates (5.3%), fiber (2.3%), protein (1.2%), fat (0.1%) and minerals, being the most important potassium (340 mg per 100 g of fresh product). It also has calcium (25 mg per 100 g of fresh product), magnesium (25 mg per 100 g of fresh product), sodium (7 mg per 100 g of fresh product), iron (2 mg per 100 g of fresh product) and zinc (0.3 mg per 100 g of fresh product). As for vitamins, the most important are ascorbic acid, retinol and folic acid (72, 20 and 23 mg per 100 g of fresh product, respectively). Other vitamins that can be found in peppers are thiamine, riboflavin, niacin and pyridoxine. Moreover, jalapeños also contain important amino acids such as lysine, methionine and valine (252, 40 and 23 mg per 100 g of protein, respectively) [7].
