Seed Biology and Pharmacological Benefits of Fennel, Lavender, Thyme and Echinacea Species

1. Introduction

Aromatic and medicinal plants have functional characteristics for pharmaceutical industries and food industries, spices, flavoring agents and dietary supplements purposes [1,2,3]. They have a set of biologically active constituents, and these natural resources encompass a range of secondary metabolites like alkaloids, phenolic compounds, terpenoids, and saponins, and show multiple biological impacts such as anti-seizure, anti-inflammatory, anti-tumor effects, etc. [4,5,6,7,8,9,10,11,12,13]. Fennel is an erect, highly aromatic perennial herb, and it reaches to a height of 2m [14,15], the flowers are produced in terminal compounds umbels, 5-15 cm wide, and each umbel section with 20-50 tiny yellow flowers on short pedicels [16]. The fruit is a dry seed 4-9 cm long and grooved, it is an open-pollination medicinal crop that needs to be pollinated by insects like bees to have utmost fruit and oil and fruit yield [17]. Fennel has been reported for its extensive activities as an antioxidant, antibacterial, anti-inflammatory, antifungal, antitumor, antithrombotic, antimutagenic, cytotoxic, bronchodilatory, estrogenic, infant colic relieving, emmenagogue, oculohypotensive, hypotensive, gastroprotective, hepatoprotective, and memory-enhancing bio-agent [18,19,20,21,22,23,24,25,26,27]. Fennel is mostly grown in semi-arid and arid regions, including Iran, and it might be an appropriate medicinal crop for drought-prone environments [28,29,30]. It is reported that the amount of compounds present in the fennel oil may change significantly because of the geographical origin and phenological state of the fennel, harvesting season, methods of extraction methodologies employed, genetic, environmental, and agricultural techniques [31,32,33,34,35].

The main components from volatile oil of fennel are 50-60% anethole and 15-20% fenchone [36,37,38,39]. Fennel remedies are traditionally utilized for their secretolytic, diuretic, and galactagogue characteristics [40], furthermore, they are usually administered to nursing babies for symptomatic treatment of dyspepsia and mild spasmodic gastrointestinal ailments [41,42,43,44]. Volatile oil recovery from plant materials is usually carried out by solvent extraction, steam distillation or hydro-distillation and enzyme assisted extraction [45,46,47]. Fennel quality is connected with essential oil content, seed yield, and active constituents concentration [48,49,50]. Health advantages of fennel seeds are anti-bacterial, anti-fungal, anti-hyperlipidemic, gastroprotective, cardioprotective, anti-anxiety, anti-diabetic and anti-cancer activities [51,52]. Ke et al. [53] found that the ethanol extract of fennel seeds notably inhibited colony formation and cell migration in lung cancer cells, reduced the viability of and triggered apoptosis in the lung cancer cell lines NCI-H661 and NCI-H446, and also showed anti-lung cancer properties through the Bcl-2 protein and may have possible as a therapeutic drug for lung cancer.

The genus Lavandula (also known as lavender) is found naturally in the Mediterranean region [54,55,56]. The plant belongs to the Lamaiceae family and different species of this genus, such as Lavandula angustifolia Miller, are largely applied in the perfumery, pharmaceutical, and food industries [57,58]. Lavender essential oil is a complicated mixture of about 20 chemical ingredient, including linalool, lavandulol, linalyl acetate, β-ocimene, lavandulyl acetate, and α-terpineol [59]. The main ingredients of lavender are known as as volatile oils (Linalole), perillyl alcohol, Limonen, Terpene, Linalile acetate, coumarin, caffeic acid, tannin, and camphor [60,61]. Its enrichment can be identified by using methods such as solvent extraction, distillation, membrane separation and supercritical carbon dioxide extraction [62]. Lavender includes effective chemical sedative components such as borneol, linalyl acetate, nerol, cinnabar, and linalool [63]. Lavender essential oil shows sedative, anti-inflammatory, anti-bacterial activity (against Streptococcus pyogenes, Pseudomonas aeruginosa, Enterobacter aerogenes, Escherichia coli, etc.) [64,65]. Lavender has shown promising potency for anxiety in different settings [66,67]. Lavender can reduce anxiety and pain, and ameliorate sleep quality and vital symptoms in patients with cancer. Thyme (Thymus vulgaris L.) of the Lamiaceae family is a perennial herb [68,69,70]. This aromatic herb has been traditionally used for culinary goals but its application in the medical field because of its anti-inflammatory, antioxidant, and antimicrobial properties [71,72,73,74]. These impacts are attributed to the chemical composition of the essential oil, which mainly consists of thymol, p-cymene, γ-terpinene, linalook, and carvacrol [75,76], other volatile components play a relevant function in thyme organoleptic characteristics, including geraniol, sabinene hydrate, α-terpineol, and eucalyptol [77,78,79,80,81]. It is well-known that volatile plant component is highly dependent upon the geographical location, influencing the components of their essential oil and bioactivities [82,83,84,85]. In this respect, plant primary and secondary components are highly affected by growing conditions including water, temperature, and other relevant parameters related to the region of production [86,87,88]. The plant extracts of Echinacea species possess antifungal, antioxidative, antiviral, antibacterial properties, and they are usually used to treat common cold, urinary, and respiratory diseases [89,90,91,92]. Extracts obtained from Echinacea species (Asteraceae) are traditionally applied in the formulation of dietary supplements and herbal medicines used as immunostimulants in the treatment of viral and inflammatory diseases [93,94,95,96]. The genus Echinacea, a favoured herbal medicine is a promising anti-inflammatory agent [97]. Echinacea contains a high level of constitutive diversity within each of its various groups of defense compounds, especially family polyacetylenes, alkamides, and ketoalkene/ynes, some of which have been used as insecticides [98,99,100,101]. A systematic review was conducted by searching electronic databases, including 600 articles. Relevant articles were selected on the basis of the nutritional, agronomical, chemical, and functional properties of fennel, lavender, thyme, and seeds of different Echinacea species such as Echinacea angustifolia DC., Echinacea purpurea L., and Echinacea pallida. The databases used were the Web of Science, and Scopus, among others. The keywords which have been used in this study were fennel, lavender, thyme, Echinacea, Echinacea angustifolia, seed production, seed biology, anatomy and germination, seed extract and pharmaceutical benefits. This work aims to provide an overview of medicinal impacts and pharmacological benefits of the seeds of important medicinal plants from recently published articles and studies.

2. Fennel (Foeniculum vulgare Mill.)

Fennel (Foeniculum vulgare) is a perennial aromatic and medicinal plant, one of the tall herbaceous plants in the family of Apiaceae (Umbelliferae) [102,103,104,105,106,107,108]. It is native to Mediterranean and southern Europe region, but has been extensively naturalized in all over the world [109,110]. This hardy perennial plant has yellow flowers and feathery leaves and yellow flowers [111], it reaches to a height up to 2.5 m with hollow stems, leaves grow up to 40 cm long with filiform segments and they are finely dissected (thread-like) of about 0.5 mm wide. The fruits are schizocarop and they include two carpels which separate at maturity into two mericarps, which has a single seed, and flowers are produced in terminal compound umbels, and the size of seed length is between 4 and 10 mm. Seeds of Apiaceae have underdeveloped rudimentary or linear embryos, and the embryo must elongate inside seeds to an important size before radicle germination [112,113]. Fennel seeds could be a promising bio-resource with meaningful interest as a rich source of both vegetable oil and essential oil and vegetable oil [114]. Essential oil composition is related to external and internal parameters influencing the plant such as ecological conditions and genetic structures [115]. Seeds of fennel have been used as a spasmolytic, anti-colic, expectorant, laxative, and digestive enzyme stimulant [116]. Hashemirad et al. [117] found that at maturity stage, freshly matured seeds of fennel have a differentiated but underdeveloped (small) linear embryo with morphophysiological dormancy. Incubation temperature and cold stratification breaks dormancy in fresh fennel seeds, and the embryo starts to grow, and seed germination increased after cold stratification even at the higher incubation temperatures such as 30 ^oC [117]. Fennel seeds have the most notable assortment of cancer prevention agents, fiber, proteins, nutrients, minerals, and fundamental oil compounds, protecting the body from oxidative pressure and lifting the safe framework [118]. The fennel seeds consist of: protein, carbohydrates, fiber, lipids, carbohydrates, fiber, minerals (potassium, iron, potassium, sodium, phosphorus), and vitamins such as vitamin E, vitamin C, vitamin B6, riboflavin, thiamine, and niacin [119]. In one experiment, it has been reported that the yield percentage of seed essential oils of fennel was 0.98, and according to GC-MS analysis, the main components of fennel seeds were estragole and anethole, and the components were categorized in the group of phenylpropanoid compounds, monoterpene, oxygenated monoterpene, sesquiterpene and ester [120]. (E)-anethole (52.-84.3%), limonene (0.5-9.4%), estragole (2.8-6.5%) and fenchone (4-24%) have been reported as the major components of the plant essential oil in natural populations [121]. Fennel seeds are a rich source of natural antioxidants, phenolic components, vitamin E and C, and oleoresins, and chief phenolic acids are vanillic, gallic, ferulic, caffeic, tannic, chlorogeic and cinnamic acid [122,123]. Fennel seeds contain proteins, fat and carbohydrate, the lignocellulosic materials, namely hemicellulose and cellulose are the principle carbohydrates in fennel seeds; hemicellulose and cellulose are natural polymers, consist of of different monomer building blocks [124,125,126,127,128,129]. Karakus et al. [130] also reported that fennel seeds were considered as an important polyphenol oxidase source. Because of higher yield and shorter duration, microwave-assisted hydrodistillation (MAHD) is an appropriate substitute alternative to extracting essential oil from fennel seeds [120]. It has been reported that fennel oilseeds by-products showed a significant antioxidant potential with high flavonoids and phenols contents and showed good antimicrobial characteristics depending on the extract type [131]. Alazadeh et al. [132] reported that the seeds of fennel may be a good alternative for complementary treatment in patients with knee osteoarthritis. Fennel seed powder can be utilized for increasing protein delta homolog 1 (DLK1) gene showing in some tissues, which has a significant function in production of adipocytes, wound healing, muscle development, lung, liver and pancreas cells development and also in the development of meat quality, growth and digestion performance [133,134,135]. Fennel seeds, added to starter feed diets, improved the growth performance and feed intake in daily calves and fattening lambs [136]. Feeding fennel seed powder before weaning had the potency to improve the BW gain and skeletal growth in dairy calves, and this was probably because of increased feed intake, reduced susceptibility to pneumonia and diarrhea, and fewer days with increased rectal temperature, pneumonia or diarrhea [137,138]. A potential carcinogen agent is estragole, is one of the basic constituents of fennel, with many medicinal activities [139,140], which is responsible for over 75% of the total essential oil content, while other components were (-)-α-pinene, (-)-fenchone, (R)-(+)-limonene, and trans-anethole [141,142,143,144]. Damjanovic et al. [145] reported that in the supercritical CO₂ (SC-CO₂), extracts as well in the hydrodistilled oil, the main components were fenchone, methylchavicol, and trans-anethole. The major fatty acid composition of fennel seed were petroselenic (67.0-71.3%) and oleic (12.0-16.4%) acids [146]. The essential oil of fennel seeds showed antibacterial activity against Escherichia coli, Staphylococcus albus, Salmonella typhimurium, Bacillus subtilis, and Shigella dysenteriae [147]. Pavela et al. [148] reported that essential oil of fennel seed indicated important insecticidal effects against Spodoptera littoralis larvae Culex quinquefasciatus larvae, and Musca domestica adults. Khammassi et al. [149] indicated that the various methanol extracts showing strong antioxidant activities with notable among locations, and cirsiliol was the major phenolic in all samples. Oktay et al. [150] indicated that the total phenolic components in the ethanol and water extracts of fennel seeds were recognized as gallic acid equivalents, and the fennel seed is also a potential source of natural antioxidant. Lee et al. [151] concluded that acaricidal activity of fennel seed oil could be because of naphthalene and carvone of which is likely to be more important because it is principal abundant than naphthalene. Ghasemian et al. [152] also discovered that fennel essential oil can be identified as a promising agent with anticancer and antimicrobial therapies. The seeds aqueous extract showed the beneficial impacts (particularly at dose of 150 mg/kg b.w.) on renal role in polycystic ovary syndrome (PCOS) rats [153]. Farid et al. [154] showed the antioxidant, anti-inflammatory, and antimutagenic impacts of fennel seeds against oxidative stress caused by γ-irradiation. The most important points about fennel is shown in Table 1. The most important health benefits of fennel seeds are shown in Figure 1.

3. Lavender (Lavandula angustifolia Mill.)

Lavender is a perennial medicinal flowering plant belonging to Lamiaceae family native to the Mediterranean region [155,156,157,158,159,160]. It has been proved that lavender showed diverse neurological impacts, such as anti-inflammatory, memory-enhancing, analgesic, neuroprotective, antidepressant, and anxiolytic [161,162,163,164]. Lavender seeds from inside the flowers and can be separated from the flower heads by shaking them gently after drying. Lavender growth stages are plantation, seed germination, sprouting, seedlings appearance, budding, production of flowers, harvesting, fruit production. Different recovery techniques including steam distillation, hydrodistillation, solvent extraction, supercritical CO₂ extraction (SCE), and novel methodologies like ultrasound-, microwave-, ultrasound-microwave-assisted, and pressurized fluid extraction have been used for the lavender essential oil recovery [165,166,167]. In order to germinate, lavender seeds needs a period of cool temperatures called cold stratification, and lavender seeds need light to germinate. Lavenders produce small, nutlike fruits containing the seeds, although plants in cultivation do not usually produce seeds, and propagation is accomplished with cuttings or dividing and planting roots. The composition and content of the lavender essential oil is related to growing location, genotype, stage of development, climatic conditions, drying method and conditions, storage conditions, and distillation conditions like pressure, duration, rate, and temperature [168,169,170]. Lavender oils include over 100 chemicals, with linalool and linalyl acetate being the two most important [171,172]. Hydroxycinnamic acids such as chlorogenic acid, rosmarinic acid, and caffeic acid, as well as flavonoids like quercetin and rutin are a few of the components primarily responsible for the antibacterial activity of lavender [173,174,175]. The major components characterized from the hydrodistillation of micropropagated plantelts were lavandulyl acetate, linalool and linalyl acetate; the major compounds identified through microdistillation of this sample were lavandulyl acetate, linalool, and linalyl acetate; and the main components of field crop plant from hydro- and microdistillation were T-cadinol, and 3-carene and borneol, respectively [176]. Lavender aromatherapy decreased anxiety in preoperative cataract surgery patients [177]. Lavender is a slow growing perennial that may bloom in its first year but takes three or more years to fully mature; moreover, their growth rate will largely rely on the variety. The main reason that lavenders will not grow is commonly because of a lack of sun, as lavenders need sandy, well draining, alkaline soils which are nutrient poor and full sun in order to grow properly. Moreover, as most lavender varieties are clones, vegetative propagation (cuttings, layering, and division of roots) is highly recommended to retain desirable traits. Plants grown from seeds are variable in growth habit, essential oil composition, and color. Different types of lavenders are spike lavender (L. latifolia), wooly lavander (L. lanata), L. heterophylla, french lavender or fringed lavender (L. dentata), Spanish lavender (L. stoechas), fern-leaf lavender (L. multifida), and L. canariensis. The traditional uses of lavender vary from application as a perfume to an antimicrobial agents.

Bensmira et al. [178] observed that the incorporation of thyme and lavender in sunflower seed oil lead to improve its thermal stability, and increased extend its frying life. Aromatherapy message with lavender oil helped to decrease neuropathic pain few weeks after the intervention and increased the quality of life in diabetic patients [179]. Its essential oil has strong antibacterial activities against Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Acinetobacter baumannii, Enterococcus faecalis, Staphylococcus aureus, and Bacillus subtilis [180]. A special lavender oil which is silexan has been proved to possess anxiolytic impacts in patients with anxiety disorders as well as significant influences on comorbid depressive signs at oral doses of 80 mg per day [181]. Pathogens associated with lavender are root rot (Armillaria mellea), dodder vine (Cuscuta epithymum), root rot (Fusarium), wilt (Fusarium solani), knot nematode (Meloidogyne incognita), stem blight (Phoma lavendulae), root rot (Phytophthora nicotianae), wilt (Phytophthora spp.), root rot (Pythium), lead spot (Septoria lavandulae), and wilt (Verticillium). The most important health benefits of lavender are shown in Figure 2.

4. Thyme (Thymus vulgaris L.)

Thyme (Thymus vulgaris L.) belongs to the mint family (Lamiaceae) and includes more than 250 species and subspecies [182,183,184,185,186,187]. It is an aromatic perennial evergreen herb, which has different biologically active components such as secondary metabolites, chemical compounds and essential oils [188,189]. The plant is indigenous to the Mediterranean and neighboring countries, Northern Africa, and parts of Asia. In Africa, the plant has been cultivated in Morocco, Egypt, Algeria, Libya, Tunisia, South African and Cameroon. The characterization of thyme oil indicated that tymol, p-cymene, carvacrol, linalool, β-caryphyllene and terpinen-4-ol are present in thyme essential oil. Lipophilic substances and essential oils are abundant in this plant [190,191]. Thyme contains various important properties, such as antiseptic, antimicrobial, antioxidant, anthelmintic, and bactericidal, activities, and it was also considered to be a natural alternative to synthetic antioxidants [192,193,194,195]. It is also rich in calcium, iron, vitamin K and manganese [196,197]. It has been well documented that the antibacterial characteristics of thyme essential oil have been related to their specific bioactive component such as carvacrol and thymol [192,198]. Yassin et al. [199] reported that the thyme extracts could be used as potential antibacterial and anticarcinogenic agents against bacterial pathogens causing nosocomial and food poisoning infections. Thyme seeds are quite small and the seedlings take quite a while to develop into acceptable sized plant. Thyme seeds are best sown in spring at a temperature of around 13^oC, and they germinate within a couple of weeks. Aside from the essential oil, the tannins, mainly represented by rosmarinic acid, contributed to the commercial use of the herb. Free phenolic acids are mainly represented by caffeic acid, gentisic acid, p-cumaric acid, syringic acid, ferulic acid, and p-hydroxybenzoic acid. In common thyme, there are around 25 various flavonoids such as (1) flavones (apigenin, luteolin, 6-hydroxyluteolin), (2) methyl flavones (cirsilineol, 8-methoxycirsilineol, cirsimaritin, 5-desmethyl-nobiletin, 5-desmethylsinensetin, gardenin B, genkwanin, 7-methoxyluteolin, salvigenin, sideritoflavone, thymonin, thymusin, xanthomicrol, (3) flavanonols (taxifolin, 2,3-dihydrokaempferol), (4) flavanones (eriodictyol, naringenin), (5) methyl flavans (2,3-dihydroxanthomicrol, sakuranetin), (6) flavonols (kaempferol, quercetin), and (7) flavone glycosides. Some of the most important health benefits of thyme are presented in Table 2.

5. Echinacea (Echinacea angustifolia DC.; Echinacea purpurea L.; Echinacea pallida)

Echinacea, often known as purple coneflower, is a herbaceous perennial native to North America that is extensively utilized for perennial gardening, wild flower establishment, and as a cut flower [223,224,225]. Plants of the genus Echinacea belong to the daisy (Compositae) family [226,227,228,229]. It is also a principle medicinal herb that recently gained international popularity due to its immunostimulatory, antibacterial and antiviral benefits to humans [230,231]. Echinaceae seeds are not tricky to harvest, and all parts of the plant are considered safe to ingest. The seeds are viable for 5-7 years, and insects are responsible for pollinating the flowers to form the seeds. Echinaceae is easy to grow from seed, but needs a cold, moist period which is known as stratification in order to better germinate. Sow seeds thickly in the fall, covering lightly to discourage birds from eating them. Strong seed dormancy has been a barrier for Echinacea field production [232]. Seed oils from three mostly cultivated Echinacea Angustifolia, Echinacea Pallida and Echinacea Purpurea are highly polyunsaturated and abundant in oleic, linoleic, and palmitic acids, together comprising 95% of the total fatty acids [233]. The glands on the outer surface of Echinacea seeds are having high components of alkyl amides [234]. Echinacea angustifolia DC., usually referred to as the narrow-leafed purple coneflower, is native to North America and cultivated in various regions of the world. Echinacea angustifolia contain caffeic acid derivatives, such as echinacoside, chlorogenic acid, cynarin, cichoric acid, as well as polysaccharides, alkamides, glycoproteins, and essential oil [235,236,237,238,239]. Echinacoside, a phenol glycoside, is the marker component for Echinacea angustifolia and it is used for the evaluation of quality of the roots even if it is not considered the main active factor of the medicinal plants [240,241]. Some parameters such prechilling, light, gibberellic acid, and ethylene influencing germination of seeds of Echinacea angustifolia DC. Echinacea purpurea (L.) Moench, a famous immunostimulant in the West, is one of the basic popular plants [242,243,244,245]. It has the C3 photosynthetic pathway [246]. It was widely used to treat gastrointestinal diseases and skin inflammation [247]. The major terpene hydrocarbons found in Echinacea purpurea extract were germacrene D, β-caryophyllene, myrcene, α-pinene, and 1-Pentadecene, respectively [248,249]. Phylloxanthobilins are important components of Echinacea purpurea extracts. The immunological, antifungal, antibacterial, and antiviral of Echinacea purpurea phytochemical constituents are well recognized [250,251,252,253,254,255]. Purple coneflower seeds (Echinacea purpurea (L.) Moench) following osmotic priming in polyethylene glycol (PEG) or matric priming in expanded vermiculite had higher rate, synchrony and germination percentage at 20 ^oC the non-primed seeds [256]. Emergence percentage of purple coneflower seeds was greater from primed seeds than from non-primed seeds in the cool regime but emergence synchrony was unchanged [257]. The poor germination of Echinacea purpurea is probably because of seed dormancy, and chilling stratification improves its germination responses [258]. Echinacea purpurea is effectual for treating upper respiratory tract infections in children [259]. Echinacea purpurea polysaccharide showed a strong hepatoprotective impact against acetaminophen (APAP)-induced drug-induced liver injury (DILI) and was connected with reduction of authophagy-dependent oxidant response, apoptosis and inflammation [260]. The whole plants of Echinacea pallida have different bioactive compounds, including caffeic acid derivatives, flavonoids, phenolics, and polysaccharides [257,258,259,260]. The dienynone was isolated from the n-hexane extract of Echinacea pallida roots and showed a selective cytotoxic activity toward cancer cells [259,260]. Echinacea pallida root extracts are identified as a representative antiproliferative activity, because of the presence of acetylenic components [261,262,263]. Chuanren et al. [264] reported that seeds of Echinaceae angustifolia are known for their deep dormancy, and both gibberellic acid (GA3) and 6-benzylaminopurine (BA) treatments shortened the mean time germination (MTG) to about 4 days, and 100dB and 1000 Hz sound wave (sine-wave) was beneficial to the germination of seeds. The most important health benefits of Echinacea are shown in Figure 3.

6. Conclusions

The fennel seeds contain lipids, protein, fiber, carbohydrates, fiber, minerals such as sodium, potassium, calcium, phosphorus and iron and vitamins such as vitamin E, vitamin C, vitamin B6, riboflavin, thiamine, and niacin. The seeds are widely used in various culinary traditions around the world. It is also used as a spice to add flavor to bread, liquors, fish, cheese, ice cream, and salad. The major components of fennel seed essential oil have been reported to be trans-anethole, fenchone, a-phellandrene and estragol (methyl chavicol), and the relative concentration of these ingredients changes considerably according to the phonological state and origin of the fennel. Some pharmacological and therapeutic properties of fennel have been attributed to the essential oils and extracts of different parts, especially seeds are anti-inflammatory, hepatoprotective, antitumor, anti-hirsutism, estrogenic, antioxidant, anti-stress, antidiabetic, oulohypotensive, anti-aging, anticarcinogenic, apoptotic, antithrombotic, antiulcerogenic, acaricide, antibacterial, antifungal, and antispasmodic activities. The most important chemical components of lavender seeds are linalool, linalyl acetate, ocimene, terpinen-4-ol, p-Cymene, cadinenes, farnesene, lavandylyl acetate, neryl acetate, phellandrene, geranyl acetate, bornyl acetate, spathulenol, o-Cymene, dihydrocarveol, copaene, carvone, thujene, and sabinene. It has been proved that lavender oil has antiseptic, antifungal, antibacterial, anti-inflammatory, and antidepressant activities. Lavender impacts have also been observed in psychological distress patients and those who suffer from neurological problems. Chemical components of thyme are carvacrol, p-Cymene, thymol, α-Pinene, thujene, terpinene, camphene, borneol, 3-Carene, spathulenol, cadinenes, eucalyptol, sabinene, bornyl acetate, 3-octanol, γ-terpinene, α-Cadinol, carvacrol methyl ether, (-)-germacrene D, cadinol, bicyclogermacrene, thymol acetate, elemene, tricyclene, α-terpinene, piperitone, ledene, geranic acid, 3-Hexanol, (+/-)-α-terpinyl acetate, viridiflorol, pinocarveol, menthyl acetate, (+)-α-cadinene, guaiene, (-)-germacrene A, p-cymen-8-ol and menthofuran. The multi-pharmacological activities of thyme ^,s seeds are anti-inflammatory, antioxidant, antibacterial, antifungal, antineoplastic and antiseptic activities. Echinacea which is a genus including different species, belongs to the daisy family. The main chemical components of different species of Echinacea species are cynarine, echinacoside, caftaric acid, beta-sitosterol, chicoric acid and phenolic acid. The main health benefits of Echinacea angustifolia are anti-inflammatory and antioxidant activity. Pharmacological activities of Echinacea purpurea are immunomodulatory effects, anti-inflammatory activities, psychoactive and cytotoxic properties. Biological properties of Echinacea purpurea are antimicrobial activity, cytotoxic activities of fractions and extracts. n-hexane and dichloromethane extracts display the highest cytotoxic activity. More researches and funds are needed in future for the development of new medicinal seed cultivars, and also it may need to promote effective application of grants to develop and progress a strategy for cultivar researches, as well as increases the accessibility of genetic diversity to grow more productive medicinal plants in different regions. Both researchers and farmers may need to consider seed science in the new way to assure future agricultural production keeps up with the pace of change in climates and weather. Some parameters such as resistance to pests and disease, effective use of nutrients, productivity, adaptation to local growing conditions, adaptation to organic farming and profitability should be also considered. All these mentioned seeds of aromatic and medicinal plants which are also rich in many nutrients can boast a wide array of pharmaceutical and health benefits.