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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_5217_Библиотеки_им_академика_М_И_Перельмана.pdf
Chapter 3 Challenges encountered in growing medicinal and aromatic plants 123
ditives have led to increased use of MAPs, their extracts, and essential oils in pharmaceutical, food, and feed industries [24]. While synthetic medication use has risen with
population growth, there is a parallel trend toward plant-based products due to concerns about medication side effects. Pharmaceutical companies are actively patenting
MAP-derived products, with about 40% of medications developed in the last two decades based on natural formulations [25]. The demand for plant products in other industries is also rising. They are used in nonalcoholic beverages and confectioneries within
the food industry and in perfumes, skin and hair care products, and aromatherapy in
the cosmetics sector [26]. Mint exemplifies a versatile MAP with diverse applications
due to its antimicrobial, antidiabetic, antioxidant, anti-inflammatory, antitumor, and
pesticide properties, finding use across cosmetics, food, agriculture, and textiles [27].
3.4 Industrial use of MAPs
Bioactive compounds from plants and their bioactive compounds are utilized across various industries. In cosmetics, essential oils from lavender, mint, and rosemary provide
aroma and therapeutic benefits [28]. The pharmaceutical sector leverages the antioxidant,
antimicrobial, and anti-inflammatory properties of plant bioactive compounds for new
medication development. The growing consumer preference for natural and organic
products has made plant extracts popular in various formulations [29]. Lavender oil, for
instance, is favored in cosmetics and shampoos for its antioxidant properties. Rosemary
extracts are valued for their antioxidant and anti-inflammatory characteristics, showing
potential in new medication formulations and as dietary supplements [30].
3.5 Essential oils
Plants produce two distinct types of oils: fixed oils and essential oils. Fixed oils consist
of fatty acids and glycerol esters, while essential oils are complex mixtures of volatile
organic compounds and various metabolites [31]. These essential oils contribute to the
plant’s distinctive taste and scent, forming its essence. They play a crucial role in the
plant’s immune and defense systems against environmental threats [32]. Essential oils
are typically extracted from the aromatic, nonwoody parts of plants, such as flowers,
leaves, fruit peels, or roots, using methods like steam distillation or hydrodistillation
[33]. These volatile liquids are insoluble in water but readily dissolve in organic solvents. The global aroma and scent industry relies heavily on essential oils, which account for approximately 17% of the sector. Common sources include rose, jasmine,
and mint [34]. MAPs, particularly their essential oils, exhibit a wide range of beneficial properties, including antibacterial, antiviral, antifungal, antiparasitic, and insecticidal activities. They also demonstrate hypolipidemic, antioxidant, and anti-toxigenic
124 Fatemeh Ahmadi, Maximilian Lackner, and August Starzinger
effects, and can help control odors and reduce ammonium and methane emissions in
ruminants [35]. Essential oils find applications in various industries as additives for
cosmetics, medical products, soaps, perfumes, ice creams, and disinfectants [36].
Emerging research explores their potential in preventing nutrient deficiencies, pest
control, and plant growth promotion. While studies have investigated essential oils
from roughly 3,000 aromatic plants, only about 300 are commercially available in
table 3.2. Of these, around 50 are in high demand for industrial and commercial use,
with just two dozen seeing regular, large-scale production [37].
Table 3.2: Industrial applications of bioactive compounds from medicinal plants [30].
Industry Bioactive
compounds
Pharmaceuticals Alkaloids and
phenolics
Cosmetics Essential oils and
flavonoids
Food and
beverages
Agriculture Terpenes and
Terpenoids and
phenolics
alkaloids
Example of plants Applications
Poppy, willow, and sage Pain relief, antioxidants, and
antibacterial agents
Lavender, calendula, and
chamomile
Mint, rosemary, and basil Flavoring, preservatives, and
Neem, tobacco, and
peppermint
Skincare, anti-aging, and hair care
antioxidant additives
Pesticides, growth regulators, and
soil enhancers
3.6 MAPs in the dye industry
The growing interest in natural dyes stems from the increased awareness of sustainability and environmental concerns. These natural colorants, derived from plants, insects,
animals, and minerals, offer more than just aesthetic appeal [38]. Many plant-based
dyes possess additional benefits such as antibacterial, antioxidant, anti-inflammatory,
and UV-protective properties due to their polyphenol, flavonoid, and anthocyanin content [39]. Numerous MAPs serve as sources of natural dyes. Chlorophyll, for instance, is
responsible for the ubiquitous green color in plants [40]. However, plants can produce
a diverse array of colors in their flowers and leaves, ranging from white and pink to
yellow and red. Even nongreen plants can harness sunlight to produce various pigments, resulting in a wide spectrum of colors [41]. The use of natural dyes in textiles
has a long history that continues to this day. These dyes play a crucial role in the textile
industry’s efforts to reduce water pollution and promote sustainable practices in both
raw materials and finished products [42]. A variety of plants yield different colors. Turmeric produces a vibrant yellow, while other yellow dyes come from woodwax, Vene-
tian sumac, and dyer’s mignonette. Additional yellow sources include Adhatoda vasica
Chapter 3 Challenges encountered in growing medicinal and aromatic plants 125
Nees leaves, jackfruit, Crocus sativus L. flowers, chamomile, Tagetes erecta L., Nyctanthes arbortristis L., and Cassia auriculata L. seeds and flowers [43]. Red dyes are ob-
tained from Carthamus tinctorious L. and Tagetes erecta L. flowers, while purple comes
from Galium aparine L. roots, onion peels, and rosemary leaves and flowers. Some
fruits, like Acanthophonax trifoliatum L. and Garcinia mangostana L., yield black dyes
[44]. Brown dyes are derived from the leaves and bark of plants such as Azadirachta
indica A., Acacia catechu, and oak trees. Tea plants can impart both color and antibacterial properties to textiles. Carotenoids in plants produce red-yellow hues, while other
pigments include orellin, bixin, annatto, mordant, and lawone [45].
3.6.1 Use of MAPs in the perfumery
The perfumes sector blends natural essential oils and synthetic organic compounds to
create unique scent experiences. The fragrance industry offers over 3,000 commercial
products, combining science and artistry in the creation of natural, herbal, animal, and
synthetic aromas. Perfume production typically involves mixing pure ethyl alcohol with
animal, herbal, or synthetic essences, stabilized for consistency [46]. Natural perfume
ingredients are extracted from various plant parts through distillation or other extraction methods. Flowers like jasmine, rose, lilac, narcissus, violet, and gardenia are common sources, as are citrus fruits like lemon and orange [47]. Of the approximately 1,500
known aromatic plant species, detailed information exists for about 500, with only 50
commonly used for essential oil production in perfumery. Key plant categories include:
Aromatic herbs (e.g., lavender, melissa, sage, rosemary, and thyme)
Flowers (e.g., rose, jasmine, orange blossom, and narcissus)
Citrus fruits
Grains and seeds (e.g., anise, dill, and cumin)
Balsams and resins (e.g., camphor, myrrh, and galbanum)
Barks and roots (e.g., cinnamon, ginger, and vetiver)
Forest trees (e.g., birch, cedar, pine, and sandalwood)
Other aromatic plants (e.g., tobacco, chamomile, and vervain)
Natural essences comprise various chemical compounds, including alcohols, esters,
phenols, aldehydes, ketones, acids, and hydrocarbons [48]. Essential oils typically contain 20–60 different chemical constituents. Terpenoids form the basis of many natural
fragrances, with different compounds contributing specific scent characteristics. For
example, menthol provides a refreshing aroma, linalyl acetate offers fruity and floral
notes, and carvone imparts a minty scent [49]. The unique fragrance profiles of various plants result from their specific combinations of secondary metabolites.
126 Fatemeh Ahmadi, Maximilian Lackner, and August Starzinger
3.6.2 Use of MAPs in cosmetics
The cosmetics industry is experiencing a surge in demand for natural and organic
products. MAPs are increasingly valued for their bioactive compounds, particularly
flavonoids, which offer skin health benefits [50]. These plants also provide essential
minerals that support overall bodily functions. The cosmetics sector favors plantbased ingredients in various formulations, utilizing a wide range of MAPs [51]. For
example, calendula flowers are incorporated into creams, shampoos, and baby products, while comfrey leaves and roots feature medicinal ointments and hair care items
[52]. Licorice root serves as a natural skin lightener, and St. John’s wort is used to combat hair loss. Grape seed oil, rich in the antioxidant resveratrol, is a popular ingredient in antiaging products. Tea extracts, particularly from green tea, are prized for
their polyphenol content, including tannins and catechins, which offer numerous
skincare benefits [53].
3.6.3 Use of MAPs in plastic production
The quest for environmentally friendly alternatives to traditional plastics has led to
increased interest in plant-based, biodegradable polymers. These materials offer a
promising solution to plastic pollution, provided they are produced sustainably from
nonfood crops or as value-added byproducts [54]. Bioplastics boast several advantages
over conventional plastics, including biodegradability, renewability, recyclability, and
nontoxic disposal. Recent research has explored the development of antioxidantactive packaging materials by incorporating MAP-derived antioxidants into polylactic
acid matrices [55]. Another study investigated the creation of biodegradable biofilms
using nanocellulose extracted from jackfruit peels, combined with plasticizers and
natural fillers. These innovations demonstrate the potential for creating eco-friendly
packaging materials that could replace petroleum-based plastics [56].
3.6.4 Other industrial applications
MAPs find diverse applications across various industries due to their antimicrobial,
fungicidal, and bactericidal properties [57]. In food preservation, they serve as natural
alternatives for meat, canned goods, and fresh produce. The animal feed industry has
successfully employed MAPs to reduce reliance on synthetic antimicrobials [58]. Many
plants are marketed as nutraceuticals in tablet or capsule form for daily nutritional
supplementation. In landscaping, certain MAP species are valued for their aesthetic
qualities and practical uses, such as forming natural hedges [59]. Research has identified potential applications in collection gardens, therapy gardens, botanical displays,
and various urban green spaces. The textile industry has also embraced MAPs, partic-
Chapter 3 Challenges encountered in growing medicinal and aromatic plants 127
ularly for their antimicrobial properties. Studies have explored microencapsulation
techniques to incorporate essential oils into fabrics, resulting in long-lasting antimicrobial and antifungal effects [60]. Various plant extracts have demonstrated strong
antibacterial activity, when applied to textiles. These innovations suggest promising
applications in hygienic textiles for medical and food industry use, as well as in the
production of naturally antibacterial clothing and home textiles [61].
3.6.5 MAPs in energy production
The growing global population, industrialization, and urbanization have led to increased fossil fuel consumption, depleting natural resources and causing environmental pollution [62]. Biofuels are emerging as a potential solution, considered the energy
source of the future. The biomass byproducts from MAP industrial processes, including fruits, roots, leaves, and flowers, offer promising potential for biofuel production
[63]. Utilizing waste biomass from aromatic industries can yield economic, environmental, and social benefits. While precise data on MAP waste biomass is limited, it is
estimated that significant amounts are produced, as essential oil content typically
comprises less than 5% of the plant material [64]. The aromatic industry is thought to
generate around 200,000 tons of solid waste annually after essential oil extraction.
This waste biomass, rich in polyphenols and other bioactive compounds, can be repurposed to create value-added products such as biogas, compost, biochar, biofuels,
and biopesticides [65]. Plants like jojoba, sunflower, rapeseed, madwort, and mole
bean are being explored for biofuel production. Maps may also contribute to solar
energy advancements. Research has shown that pigments extracted from plants like
Malabar spinach and red cabbage can absorb green light while reflecting red and blue
light, suggesting potential applications in developing multicolor solar cells for agrivoltaic systems [66].
3.6.6 MAPs in agricultural applications
MAPs offer various agricultural applications, particularly in pest management. Plants
naturally produce secondary metabolites like esters, ketones, and essential oils as defense mechanisms against pests and mites [67]. These compounds exhibit neurotoxicity, growth regulation, and enzyme-inhibition effects on pests. For instance, fennel extracts have demonstrated high toxicity against mosquito larvae, with terpineol and
1,8-cineol proving particularly effective against mosquito bites. Vetiver root extracts
show promise as an eco-friendly insecticide against certain beetles [68]. Oregano has
been suggested for agricultural pest control due to its insecticidal, antiviral, antibacterial, and antifungal properties. Industrial cannabis flowers secrete cannabinoids and
terpenes that repel plant-eating insects [69]. Studies have shown cannabis essential
128 Fatemeh Ahmadi, Maximilian Lackner, and August Starzinger
oils to be toxic to various pests while remaining harmless to nontarget invertebrates.
Intercropping MAPs with vegetables can protect crops from pests, extend storage periods, and improve quality during transport [70]. Essential oils from aromatic plants
also help combat soil nematodes. This practice can alter soil composition, decreasing
pH and nitrogen while enhancing organic nitrogen and water content. MAPs show potential in phytoremediation of heavy metal-contaminated soils [71]. Some species can
accumulate heavy metals without transferring them to their essential oils, suggesting
their suitability for cultivation on polluted lands while still producing economically
viable products [72]. It is important to note that environmental factors such as salinity, temperature, light, and nutrient availability significantly influence the synthesis
and accumulation of secondary plant metabolites. These factors warrant further detailed exploration to optimize MAP cultivation and utilization [73].
3.7 Salt stress
Salt stress significantly impacts the development and morphology of medicinal plants.
It hinders germination by damaging the embryo or reducing soil potential, impeding
water uptake. This effect has been observed in various plants, including Ocimum basi-
licum, Eruca sativa, and Petroselinum hortense [74]. The seedling stage is particularly
vulnerable to salt stress. Studies have shown that salinity impairs seedling growth in
plants like Thymus maroccanus by inhibiting food reserve mobilization and cell division. Similar effects have been noted in basil, chamomile, and marjoram. Salt stress
also affects mature plants. In Aloe Vera, increased salinity led to decreased foliage,
root growth, and dry matter, primarily due to reduced total soluble solids [75]. Citro-
nella java plants exposed to high salinity showed a significant reduction in tiller numbers. Cumin’s vegetative and reproductive stages were found to be highly sensitive to
salt stress [76]. Growth inhibition due to salinity has been reported in numerous medicinal plants, including Majorana hortensis, peppermint, and Matricaria recutita.
Mentha piperita var. officinalis and Lipia citriodora var. verbena exhibited reduced
leaf numbers, area, and biomass under salt stress. Milk thistle exposed to high salinity
showed decreased plant height, leaf count, and capitula number [77].
3.7.1 Nutrient
Uptake of salt stress disrupts nutrient uptake in plants by creating an ionic imbalance.
The abundance of Na
trients like K
+
, Ca2+, and NO
ing, and transport within the plant system. Studies on various medicinal plants have
shown decreased levels of N, P, K
+
and Cl– ions interferes with the absorption of essential nu-
-
. This imbalance affects nutrient availability, partition-
3
+
, Ca2+, and Mg
2+
under salt stress conditions [78].
Chapter 3 Challenges encountered in growing medicinal and aromatic plants 129
3.7.2 Productivity
Increasing salt concentrations negatively impact the productivity of medicinal plants
such as fennel, cumin, and milk thistle. Salt-stressed plants typically show reduced
fruit yield per plant and fewer umbels [79].
3.7.3 Photosynthesis
Photosynthesis, a crucial physiological process for plant growth and survival, is particularly vulnerable to salt stress. The stress disrupts the metabolic balance within
plant cells, affecting the photosynthetic machinery. Many medicinal plants, including
Thymus vulgaris and Satureja hortensis, show reduced chlorophyll content under salt
stress [80]. This decrease is attributed to inhibited chlorophyll synthesis and increased
degradation, leading to suppressed photosynthesis. Salt stress also negatively impacts
chloroplast development and protein translation within plastids, sometimes resulting
in plastid degradation, as observed in fennel [81].
3.8 Drought stress
Drought stress significantly affects the growth, development, and secondary metabolite
production of medicinal plants [82]. As global climate patterns shift, understanding how
water scarcity impacts these valuable species becomes increasingly important. Medicinal
plants, prized for their therapeutic properties, show complex responses to drought that
can both hinder growth and enhance the production of certain beneficial compounds.
Under drought conditions, medicinal plants typically close their stomata to conserve
water [83]. While this helps reduce water loss, it also limits carbon dioxide uptake,
compromising photosynthesis and overall growth [84]. Plants often exhibit stunted
growth, smaller leaves, and reduced biomass, along with visible signs like leaf rolling
and wilting. Interestingly, water scarcity can trigger increased production of secondary
metabolites, the compounds responsible for medicinal properties. Plants in semiarid
conditions often show higher concentrations of active substances compared to those in
moderate climates [85]. This increase is linked to the plant’s stress response and altered
metabolism. Drought causes an imbalance in the cellular redox state, leading to reactive
oxygen species (ROS) accumulation [86]. To combat this, plants enhance their antioxidant defenses, producing more secondary metabolites like phenolic compounds, flavonoids, and terpenoids. These not only protect the plant but also contribute to its medicinal value. For example, drought-stressed sage plants produce higher concentrations of
monoterpenes, key components of their therapeutic properties [87]. The enhancement of
secondary metabolite production extends to other compounds like alkaloids. In Cathar-
130 Fatemeh Ahmadi, Maximilian Lackner, and August Starzinger
anthus roseus, valued for its anticancer alkaloids, drought stress upregulates genes involved in alkaloid biosynthesis, increasing the concentrations of these valuable compounds [88]. However, while active substance concentration may increase under
drought stress, total yield can be affected by reduced biomass production. In some cases,
the concentration increase outweighs biomass reduction, resulting in higher total metabolite production per plant [89]. In others, biomass reduction may lead to an overall decrease in active compound yield. The response to drought stress is further complicated
by interactions with other environmental factors like light intensity and temperature
[90]. The duration and severity of drought also play crucial roles in determining its impact. Mild to moderate water deficits may stimulate secondary metabolite production
without severe damage, but prolonged or severe drought can lead to irreversible harm
or plant death. Understanding these effects has important implications for medicinal
plant cultivation and natural medicine production [91]. Careful water management may
enhance product quality without significantly compromising yield. However, implementing such strategies requires a thorough understanding of species-specific responses and
optimal stress levels. Long-term drought exposure can lead to genetic and epigenetic
changes, altering plant characteristics over generations. This highlights the importance
of conserving diverse plant populations and their habitats, as they may harbor valuable
traits for drought resistance and metabolite production [92]. As research advances, developing sustainable cultivation practices that balance plant productivity with highquality medicinal products will be crucial. Understanding drought stress mechanisms
may provide insights into improving plant-based medicine efficacy and production, contributing to the ongoing importance of medicinal plants in healthcare and traditional
medicine systems worldwide [93].
3.9 Heavy metals
Heavy metals can significantly impact medicinal plants, affecting their growth and
phytochemical production. While plants need certain metals for growth, excessive
amounts become toxic [94]. Plants can accumulate both essential and nonessential
metals, potentially leading to enzyme inhibition and oxidative stress damage to cell
structures. Heavy metal contamination in medicinal plants can occur through cultivation, processing, or intentional addition for alleged medicinal purposes [95].
The increasing use of herbal drugs has raised concerns about heavy metal contamination in medicinal plants [96]. Metal accumulation in plant tissues can alter physiological and biochemical processes, affecting plant health, productivity, and the safety and
efficacy of derived herbal medicines. Heavy metal stress often reduces overall biomass
production in medicinal plants by interfering with essential processes like photosynthesis, respiration, and nutrient uptake [97]. For example, cadmium exposure can cause
chlorosis, leaf rolling, and premature senescence, decreasing plant vigor and yield. Root
Chapter 3 Challenges encountered in growing medicinal and aromatic plants 131
systems, often the first point of contact with soil metals, may experience reduced elongation, decreased biomass, and altered architecture, further impacting water and nutrient absorption [98]. Interestingly, heavy metal stress can have complex effects on phytochemical production, sometimes stimulating secondary metabolite production as part
of the plant’s stress response. Moderate metal stress may increase phenolic compounds,
flavonoids, and antioxidants in some species, potentially enhancing their therapeutic
value [99]. This response is often associated with the plant’s attempt to mitigate ROS
damage caused by heavy metals disrupting cellular redox balance. However, the relationship between heavy metal stress and secondary metabolite production is not
straightforward [100]. Severe or prolonged exposure can suppress important phytochemical biosynthesis due to overall plant health deterioration. The outcome depends
on metal type and concentration, plant species, and genetic factors. These stressinduced changes in phytochemical profiles have significant implications for medicinal
properties and therapeutic applications [101]. While some changes might enhance certain medicinal properties, they can also lead to unpredictable variations in therapeutic
effects. The accumulation of heavy metals in medicinal plants raises serious safety concerns for herbal product consumers. Despite potential enhancements in beneficial compounds, the presence of toxic metals poses significant health risks. This issue is particularly problematic as many users perceive herbal medicines as inherently safe [102].
While regulatory bodies have established guidelines for acceptable heavy metal levels
in medicinal plant products, global enforcement remains challenging, especially in regions with limited regulatory oversight.
Long-term heavy metal exposure can induce genetic and epigenetic changes in
medicinal plants, affecting their stress adaptation and phytochemical profiles across
generations [103]. This underscores the importance of protecting natural habitats
from metal pollution and developing cultivation strategies in controlled, uncontaminated environments. Some medicinal plants can hyperaccumulate heavy metals, presenting challenges for medicinal use but offering potential in phytoremediation [104].
These species could serve dual purposes: cleaning contaminated soils while producing
biomass for nonconsumptive applications, such as extracting specific compounds for
industrial or pharmaceutical use. The complex interactions between heavy metals
and medicinal plants require a multidisciplinary approach, combining plant physiology, biochemistry, pharmacology, and environmental science. Researchers are developing advanced analytical methods and molecular biology approaches to better understand these interactions [105]. Heavy metals have diverse effects on medicinal
plants, generally negatively impacting growth but sometimes increasing the production of certain beneficial compounds. However, potential enhancements in medicinal
properties must be balanced against health risks from metal accumulation in plant
tissues [106]. As herbal medicine use grows globally, comprehensive strategies for
monitoring and controlling heavy metal contamination in medicinal plants are crucial
[107]. This includes implementing strict quality control measures in cultivation, harvesting, and processing, as well as thorough safety assessments of herbal products.
132 Fatemeh Ahmadi, Maximilian Lackner, and August Starzinger
Ongoing research into plant responses to heavy metal stress may lead to new strategies for enhancing valuable phytochemical production, while minimizing contamination risks [108]. A balanced approach considering both the potential benefits and risks
of heavy metal interactions with medicinal plants is essential for the sustainable and
safe use of herbal medicines in the future.
3.10 Heat stress
Heat stress significantly impacts medicinal plants’ growth, development, and phytochemical composition. As global temperatures rise due to climate change, understanding these effects becomes increasingly important [109]. When exposed to heat stress,
medicinal plants often close their stomata to conserve water. While this reduces transpiration, it also limits carbon dioxide uptake, compromising photosynthesis and
overall growth. This can lead to stunted growth, smaller leaves, and reduced biomass
production [110]. Heat stress can alter the chemical composition of essential oils in
plants like Mentha × piperita L. var. Mitcham and Mentha arvensis var. piperascens
Malinv. ex L. H. Bailey. For instance, menthol percentages may decrease, while pulegone and menthyl acetate increase, affecting the plant’s medicinal properties and
commercial value [111]. Long-term heat exposure can induce genetic and epigenetic
changes in plant populations, potentially altering their stress adaptation abilities and
phytochemical profiles across generations. This highlights the need for habitat protection and controlled cultivation strategies. Interestingly, heat stress can sometimes
stimulate secondary metabolite production as part of the plant’s stress response [112].
Moderate heat stress may increase phenolic compounds, flavonoids, and antioxidants
in some species. This is believed to be a defense mechanism against heat-induced oxidative stress. Plants enhance their antioxidant defense systems to combat ROS accumulation caused by high temperatures. This includes producing secondary metabolites that protect against oxidative damage and contribute to medicinal properties
[113]. However, the relationship between heat stress and secondary metabolite production is complex. While moderate stress might enhance certain compounds, severe
or prolonged exposure can suppress important phytochemical biosynthesis due to
overall plant health deterioration. At the molecular level, heat stress triggers heat
shock protein (HSP) expression, which protects cellular proteins from denaturation.
Plants also activate antioxidant defense systems, increasing the production of enzymatic antioxidants like superoxide dismutase and nonenzymatic antioxidants such as
ascorbic acid to scavenge ROS and protect cells from oxidative damage [114].
Heat stress significantly impacts medicinal plants’ hormonal balance, affecting various physiological processes. Abscisic acid production often increases under heat stress,
promoting stomatal closure to reduce water loss, but limiting CO
thesis. Other hormones like ethylene and salicylic acid also play roles in heat stress re-
uptake and photosyn-
2