Chapter 1: Natural Products for Cosmeceuticals

Natural cosmetics are made up of natural products containing only natural raw materials that are directly obtained from nature, like ingredients from plants, animals, mineral resources and renewable natural resources.¹ The raw materials undergo very little processing, due to which they possess minimal impact on humans, animals and the Earth. Thus, these are produced in an ecological, sustainable and ethical way. Each raw material required for the formation of natural cosmetics has a rich composition and various properties, like anti-oxidant, anti-aging, anti-inflammatory, anti-wrinkle, acne reducing, skin dehydration, cleansing, skin lightening, emulsification, exfoliation and surfactant effects.^2–4 

Products that can act as both cosmetics and medicine are called cosmeceuticals. They can be combined as cosmetic products with pharmaceuticals. In essence, they are biological active ingredients that possess medical benefits. The active substance helps in beautifying, cleansing, promoting attractiveness, or altering the appearance without affecting the structure or function of cosmeceuticals. The term cosmeceutical (Figure 1.1) is less common than the term cosmetics.⁵ Although both of them are associated with beauty and are categorized under beauty products, they are different from each other. Cosmetics work on the outer layer of the skin and beautify the skin externally, but do not cure the skin internally. As a result, the effect is temporary and immediate. Meanwhile, cosmeceuticals are a combination of cosmetics and natural ingredients that have healing properties, which cure skin-related problems internally. When the product is applied on the skin, it penetrates from the epidermis and works on the dermis area. Cosmetics do not have rejuvenating properties, while cosmeceuticals do have this property.⁶ 

Synthetic products are mainly used nowadays in the production of cosmetics because they are cheap in price compared to other natural cosmetics and they also have a longer shelf life. However, many of the synthetic cosmetic formulations contain paraben, toluene, oxybenzone, artificial fragrances or phthalates, which have carcinogenic potential and also have a negative impact on the environment. In contrast, natural cosmetics do not contain any synthetically created ingredients. A natural product is extracted or produced in a sustainable way, but the products used in synthetic cosmetics are engineered to mimic natural ones. The natural products used in cosmetics are synthetic chemical-free, cause less irritation, are eco-friendly and have long term benefits.⁷ 

There are various sectors in which cosmetic products are used, such as in hair care, skin care, lip care, nail care, toiletries and perfumery. An outline of the different types of cosmetic products used in the field of cosmetics has been provided in Figure 1.2.

The word ‘cosmeceuticals’ was believed to be used for the first time in the 20th century. It was coined by Raymond Reed, a founding member of the United States Society of Cosmetic Chemists, in 1961. Albert M. Kligman, a professor at the University of Pennsylvania Medical School, discovered that topical retinoic acid (or tretinoin) can be used for both acne and wrinkle treatment, and was thus called the father of cosmeceuticals. However, cosmeceuticals only became popular on the market in 1996.⁸ Table 1.1 depicts the history of natural cosmetics.

Natural cosmetics act as anti-oxidants, emulsifying agents, anti-aging, anti-inflammatory, anti-microbial, anti-tumor, anti-wrinkle and UV protective agents, exfoliants, emollients, and surfactants. For instance, ferulic acid is a derivative of plant phenolic content and is commonly found in grapes, apples, etc. It acts as an anti-oxidant and is also used as a skin whitening agent. Anti-oxidants also fight against skin aging by reducing the amount of free radicals.¹⁵ Glycyrrhizic acid is a compound isolated from licorice that is used as an anti-inflammatory agent.¹⁶ Coco beans contain triglyceride compounds such as linoleic acid and palmitic acid, which are used in reducing wrinkles. Several products, such as shea butter, soyabean oil and sunflower oil, act in reducing aging effects. Fatty acids, long chain esters, lanolin and beeswax are used in skin moisturizing formulations because of their emollient properties.¹⁷ Egg yolk, mustard and honey act as natural emulsifiers, and play an important role in combining immiscible fluids into an emulsion.¹⁸ Humectants have long-lasting moisturizing effects, and act by binding water. Some of the natural humectants are aloe, honey and glycerol. Exfoliants are found in milk, fruit and sugar cane. They have the ability to remove the outer layer of dead skin cells, and stimulate new cells to grow.¹⁹ Potassium cocoate is derived from coconut oil and is used as a surfactant. Thus, it is used for cleansing and foaming, and has anti-microbial effects.²⁰ 

There is increasing demand for the use of environment-based natural beauty products. With the rise of the chemical content in cosmetic products and awareness among consumers, companies have shifted themselves towards manufacturing natural cosmetics; for instance, L’Oreal has launched a plant-based hair dye named Botenea. There are various countries, such as in the Asia-Pacific region, Europe and North America, which have set some standards for regulating the natural cosmetics market, including Ecocert, the Soil Association, Cosmebio, ICEA, BDIH, OASIS, NPA, and NSF. There has been growth of the natural cosmetics industry in the past few years due to the rise in demand for synthetic chemical-free skin, and this trend is expected to continue during the forecast period. The revenue for the natural and organic market stood at 11.92 billion U.S. dollars in the year 2021, and there will be a rise to 18.07 billion U.S. dollars by the year 2027 according to the data (Figure 1.3) provided by Statista Consumer Market Outlook.²¹ 

Nowadays, advancements and developments in the cosmetic industries are emerging at a quite rapid rate. Products that cause no harm and are safe to use can be speculatively applied on the skin surface, i.e. locally or topically. Agricultural extracts are broadly used in cosmeceuticals because of their role in the maintenance of the well-being, appearance and purity of skin, hair and nails. The most accepted botanical products used by skin specialists include soy, teas (green, white and black), chamomile, caffeine and coffeeberry.²² 

Many compounds used in hand sanitizers attenuate the transference of contagions and thereby prevent the spread of pathogens. One such organic and humidifying hand sanitizer was manufactured based on the antibacterial effect of alcohol in addition to Abelmoschus esculentus (okra) polysaccharide, which helps to soothe, soften and increase the moisture levels in the skin. After a lot of preparatory assessments and quality examinations, certain outputs were revealed that suggest: (i) good moisturization potential; (ii) hydrated skin; (iii) non-irritability, (iv) better cleanliness of the hands; and (v) synergistic activity along with triclosan to avoid dry and rough skin.²³ 

Utilizing natural polymers in cosmetic formulations has greatly expanded as a result of the cosmetics industry’s desire to move towards sustainable biobased raw ingredients, such as natural polysaccharides. Emulsions are the most common formulations for skincare because of their feasibility and adaptability in the pharmaceutical industry. Baptista et al. studied emulsions of olive oil and α-tocopherol using an emulsifying agent such as FucoPol, an exopolysaccharide with a high molecular weight that contains carbohydrates, glucuronic acid, etc.²⁴ Herein, FucoPol was found to be better than other emulsifiers, available commercially. The synergistic anti-oxidant activity of FucoPol and α-tocopherol, along with the capability of FucoPol to heal wounds, has made it a promising biomaterial for the formulation of cosmetics.

Emulsions prepared using high frequency ultrasound technology (HFUT) without the need for any additive ingredients or emulsifying surfactants have differential properties. In comparison with reference emulsions, HFUT showed twice lower average droplet size and thrice greater viscosity, and furthermore it exhibited better applicability for cosmetic preparations.²⁵ The in situ gelation was evaluated for cosmetic emulsions prepared using two alginates, having a richer content of mannuronic acid or glucuronic acid compared with a biopolymer reference, such as xanthan gum. The results were consistent with those of traditional polymers, and the emulsion that contained the gelled form of the alginate had significantly higher viscoelastic characteristics and dynamic viscosity, and great consistency.²⁶ 

Natural tri-glycerides obtained from derivatives of l-ascorbic acid that are lipophilic have been used as ingredients for cosmetics. Both plant and animal fats were investigated as trans-esterification substrates for ascorbic acid by lipase and their anti-oxidant capabilities in skin care products were assessed. The research showed that the formulation included ascorbyl esters, linseed oil, and coconut oil with a high potential to scavenge 2,2-diphenylpicrylhydrazyl (DPPH) radicals. Furthermore, the saturated medium side alkyl chain esters showed quicker diffusivity than the long chain ones.²⁷ 

For a very long time, organic triglycerides have been included in cosmetic formulations. A natural ingredient in cosmeceuticals, bio-based algae oil, has a long shelf life, excellent thermal and oxidative stability, and high moisturizing capacity.²⁸ Skin has many barriers before absorption, of which the stratum corneum is the main one. Natural and organic products have been used to overcome this hurdle. A lipid called phytosphingosine (PS) is found in the stratum corneum naturally, both in its free form and as part of a major proportion of ceramides. The formulation containing phytosphingosine showed excellent antibacterial, antiseptic and anti-inflammatory activity for the treatment of acne.²⁹ 

Natural product-based cosmeceuticals have grown in popularity as the demand for vitamins and plant-based goods has increased in a subset of the cosmetics industry. They are used in cosmetics and health-related products because of their anti-oxidant, anti-microbial, anti-aging, UV protection, cytoprotective, anti-carcinogenic, and anti-inflammatory characteristics. Their drawbacks, namely their poor solubility, instability, decreased skin penetration, and brief skin retention period, severely limit their applications in topical formulations. The utility of nanotechnology as an advanced tool may help to encapsulate them in order to overcome their drawbacks and deliver them to the skin in a controlled manner.³⁰ Similarly, Souza and co-workers worked using beeswax-based nanoparticles and incorporated them into gel-based formulations. These formulations have been shown to increase the stratum corneum water content and decrease trans epidermal water loss. The innovative natural bees wax-based nanoparticles demonstrated potential for skin restoration and opened the door to their possible commercial usage as a unique natural ingredient in dermatology and cosmetics for impaired skin barriers.³¹ It is possible that hydroxycinnamic acids,³² extracts or bioactive ingredients of mushrooms³³ and Acmella oleracea,³⁴ may serve as the basis for cosmeceutical formulations to deal with anti-ageing, anti-wrinkles, inflammation, and skin pigmentation. To attain the same bioactive goals, the extracts were further mixed into a basic cosmetic cream after analyzing the phenolic acids and ergosterol.

Skin aging is a normal, physiological, biochemical, and time-sensitive process that is caused by a complex interaction between internal and external variables. These long-term modifications to the skin’s layers, morphology, metabolism, and appearance are detrimental. Gallic and ferulic acids, as well as herbal formulations containing Thymus vulgaris, Panax ginseng, Triticum aestivum, or Andrographis paniculata, are some of the most convincing natural ingredients for the formulation of novel dermo-cosmetics with anti-skin aging effects.³⁵ To slow down the progression of skin ageing, many natural organic compounds are incorporated into formulations, including moisturizers, herbal components, minerals, growth factors, exfoliants, vitamins, and proteins. Utilizing bioactive compounds that are derived from natural resources is a recent trend in anti-aging research. The anti-oxidant polyphenol is found in many consumable products and scavenges free radicals and gets rid of metabolic waste products. So, vitamin C and annatto seed powder acting as an anti-oxidant and natural colorant are added to reacetylated chitosan films and their use as an anti-aging skin mask was proposed.³⁶ Chitosan has been used for a variety of purposes, such as sun-protection, photo-aging, as a depigmenting agent in skin lighteners, in skin exfoliation, and in preventing the loss of fragrant ingredients.³⁷ Vitamin C and peptides, along with additives such as hyaluronic acid and mineralizing water, work as anti-aging agents, and have been widely used in dermatological products. These formulations are prepared at low pH and have been proven to have effectiveness in anti-wrinkles, anti-aging and skin regeneration.³⁸ 

The fermentation of the black yeast fungus Aureobasidium pullulans produces pullulan, a naturally occurring edible polymer utilized in numerous cosmeceuticals. It is a water-soluble, edible, non-mutagenic, and non-toxic polymer. Pullulan and dioxybenzone are conjugated, which lessens the negative effects of lower photoabsorption intensity, with a considerable capacity for epidermal retention. Pullulan films are non-sticky, and they can be applied to the skin with ease because they are in a semi-liquid gel form. The hydrogel composition gives the skin on your face solidity, reduces lines, and restores suppleness.³⁹ 

In contrast to land resources, marine resources have unique biochemical properties, and the demand for cosmeceuticals from these sources has increased tremendously in the past few years. The most significant repository of biodiversity is found in marine habitats, which also include biologically active compounds with untapped potential for use in medicines, nutraceuticals, and cosmeceuticals. Agar and carrageenan, which function as gelling and thickening agents to raise the viscosity of cosmetic compositions, are valuable bulk ingredients for the cosmetic industry. Various small compounds, such as ectoine, trichodin A, mytiloxanthin, kojic acid, sargafuran, chrysophanol, scytonemin, astaxanthin, mycosporine-like amino acids (MAAs) and PUFAs, have been used in the cosmetics industry due to their various characteristics, such as anti-wrinkle, skin hydration, anti-aging, anti-acne, anti-microbial, promoting skin hydration and reducing pigmentation.⁴⁰ 

The search for alternative excipients that maintain functionality and cosmetic appeal has intensified as a result of growing customer demand for topical solutions that are safer, more organic, and durable. The primary variables include viscoelastic and sensory properties, the composition of the surfactant, and the presence of thickeners. A. Ali et al. utilized a human panel to analyze the tactile and sensory qualities of topical lotions. They compared starch and surfactant-based Pickering cream and the results showed that the starch-based formulation ranked lower for greasy, tacky, and squishy properties.⁴¹ 

Lignin, an aromatic component of plants rich in carbon content and having UV chromophoric properties, has been used as a photo-protective agent through the incorporation of submicrometric particles into cosmetological products. The results revealed that adding submicrometric lignin particles to a lotion would result in excellent anti-oxidant properties and UV protection properties, providing an opportunity for the usage of by-products in the lignocellulose biorefinery industry.⁴² Dermatocosmetic products are used to remove cosmetic flaws and cause no interference in the skin rejuvenation process. By speeding up keratinization and exfoliation, abrasive ingredients can be found in many cleansing products to improve skin conditions. Kozlowska and co-workers developed sodium alginate microparticles and compared them with their combination with starch using peeling technology. The spherical, uniform shape of the produced microparticles reduces the possibility of skin irritation during peel application, thus creating possibilities for new applications in the cosmetics sector.⁴³ 

Melanogenesis, a sequence of enzymatic chemical reactions, involves the manufacture of melanin, a pigment responsible for the pigmentation to the skin, eyes, and hair. The production of melanin is essential for enhancing the body’s defense against the damaging effects of ultraviolet radiation, particularly in the genetic material of melanocytes. Its production in excessive amounts might result in dark patches and skin darkening. Researchers have examined natural sources of melanogenic inhibitors, such as Leathesia difformis, Morus alba, Euphorbia supina, Syzygium polyanthum, Orostachys japonicus, Libidibia ferrea, Heracleum moellendorffii, Pouteria torta, Coix lacryma-jobi-adlay, Inula britannica, sappanone A, cinnamaldehyde, Artemisia argyi, Vitex negundo, and Gaillardia aristata. The phenolic content present in these sources was reported to be anti-oxidant and anti-melanogenic.⁴⁴ 

The addition of small concentrations, such as 0.1% for normal hair or 0.5% for damaged hair, of cationic polymers to shampoos can cause an increase in their efficacy and also improves the smoothening and creaminess properties of the hair. In a study reported in 2000, Sander and co-workers reported that guar gum cannot be used as a cationic polymer as it cannot be desorbed, which results in over-conditioning of the hair and causes build-up.⁴⁵ 

Hair oil contains 70–80% of base oil, e.g. rice bran oil, light liquid paraffin oil or refined sesame oil, and 15–25% of additives, e.g. herb extracts, menthol, camphor, butylated hydroxytoluene, cinnamon, or vetiver oil. Hair oils are expected to provide strength and nourishment to the hair by reducing hair loss and inducing its rapid growth. The extent of penetration of hair is measured by laser scanning confocal microscopy (LSCM), a technique used to observe 3-D samples in their natural environment using fluorescent Nile red dye without destroying the sample integrity. In a study reported by Dandekar et al., the penetration of mineral oil was faster than that of vegetable oil.⁴⁶ 

Usually, polymers are used in hair care products as they make the consistency of hair thick and provide protection. Nevertheless, these materials are non-biodegradable and have some disadvantages. Polymers of a synthetic nature gather on the scalp and cause an exasperating coat through which any advantageous substances cannot permeate. Prolonged use of these materials causes permanent damage and consequently results in breakdown of the hair. Collagen extracted from fish waste was found to show positive action on hair according to the study conducted by Igielska-Kalwat and co-workers with the removal of extravagant sebum production and the maintenance of proper pH of the hair.⁴⁷ 

Encapsulated nanotubes have been used for the treatment of hair and formulation of dyes, where the encapsulation created through the nanotubes provides a prolonged drug effect. The prominent penetration of drugs in the cuticle pores delivers the drug directly onto the surface of hair. Nanotube technology has shown good results on both human and other mammalian hair. The use of biodegradable and natural substances has resulted in better therapeutic and cosmetic formulations for human as well as veterinary use.⁴⁸ 

The long-term accumulation of excessive arsenic in body tissues may lead to chronic arsenic poisoning. Tube wells are the leading sources of this arsenic rich water. The use of spirulina extract with a combination of anti-oxidant zinc produced notable positive results for the treatment of chronic arsenic poisoning. Randomized control studies conducted in Bangladesh evidenced that the use of a spirulina extract and zinc combination effectively reduced the concentration of arsenic from hair scalp and skin tissues by increasing its excretion through urine. By using this combination, symptoms of hyperpigmentation and skin lesions were significantly improved.⁴⁹ 

In the hair-care sector, baldness and early greying of hair are the two main challenges that individuals endure. Drug repositioning is a drug discovery technique in which a current medication is used as a treatment for a different illness. Many drugs, like minoxidil, discovered to treat hypertension were found to provoke hair growth due to their vasodilation activity. Similarly, drugs like tofacitinib and ruxolitinib also induce hair growth. Bimatoprost is another drug that restores hair growth and melatonin is a hormone used for the treatment of patterned hair loss. Another problem faced by people is early greying of hair. Latanoprost, which was earlier used for the treatment of glaucoma, was found to stimulate hair pigmentation. Also, high doses of p-amino benzoic acid cause darkening of the hair.⁵⁰ 

Anthocyanins are hydrophilic compounds present in fruits, vegetables and grains, which impart red color under acidic conditions and purplish-blue under alkaline conditions. Their anti-oxidizing and anti-inflammatory properties indicate their use in the pharmaceutical and cosmetics industries. Anthocyanin-based compounds are used in hair products as they show positive effects on the melanin content of hair. For instance, organic dyes excavated from natural origins, like blackcurrant fruit skin, impart intense blue color to the hair when paired with anionic base quinonoid in acidic conditions. The use of natural dyes serves as a replacement and mitigates the negative effects brought on by the use of synthetic dyes.⁵¹ 

Surfactants are used as emulsifying and cleansing agents in the cosmetics industry. Glycolipids are one of the natural surfactants that can be used in hair cosmetics. Four different rhamnolipids and an alkyl polyglucoside are promising glycolipid surfactants. Based on the study conducted by Laura Fernández-Peña and co-workers, when the beneficial effects of a combination of synthetic surfactants and polymers were compared with natural glycolipids and proteins, it was found that surfactants with short hydrocarbon chains show good efficacy.⁵² 

Natural conservatives or preservatives having anti-bacterial activity have been widely used as compared to synthetic ones owing to their safety and non-toxicity. Studies conducted to prove that the extract of Rubus rosaefolius Smith is a better organic conservative primarily included compositions in the form of an emulsion or gel.⁵³ A number of bacteria and fungi were tested by preserving them with the mentioned preservative in either emulsion or gel form and it has shown satisfactory efficacy as an organic conservative to be applied on the skin surface against Gram positive and negative bacteria, rather than fungi.

According to the European pharmacopoeia, essential oils are defined as the formulated compounds of refined organic components derived from scented plants through various methods. Volatile oils and their particular ingredients are extremely aqua-phobic and act as either the main component or as a conservative in different cosmeceuticals and toiletries. Some examples of volatile oils are Apium graveolens, Salvia officinalis, Artemisia judaica, etc. The components of such volatile oils play a major part in the destruction of bacteria and fungi, and thus have acquired a wide place in the manufacturing of cosmeceuticals; however, they do not always have a definite impact, as they do have side effects like hypersensitive reactions. The important ingredients of volatile oils are isoprenoids, cinnamic acids and terpentines. Volatile oils carrying Calendula officinalis and Osimum basilicum are exceedingly used to prepare sun-tan lotions as they soak up most of the ultraviolet light, avoid dermatoheliosis, and protect from tanning, sun creasing and other skin problems. However, applying them for a long duration might result in allergies and skin infections, and could even be noxious to the liver. The volatile oils having high incidences of these side effects are peppermint oil, tea tree oil, eucalyptus oil, and lavender oil. Thus, additional examinations are required to get a better outcome of these products.⁵⁴ 

The crystalline dextrins, such as cyclic glycans, ‘cyclodextrins’ and their derivates, are used as a medium to intensify the solvability of weakly soluble substances, increase the penetration of drugs through the mucosal/skin membrane and upgrade the bio accumulation of drugs. They are often used in nutritional agents and toiletries. Because of their aquaphilic nature and high molecular weight, they do not permeate through the oleophilic membranes and hence make the membrane flawless. The most used organic Schardinger dextrins are alpha, beta and gamma cyclodextrins that are ring shaped, having an aquaphilic exterior region and being oleophilic in the interior. Their physical and chemical characteristics are the same as those of their straight chain by-products, but because of their cyclo-structure they are only a bit affected by the enzymes. Also, they are far better building and dispersive agents. They elevate the consumption of drugs coming under bio-pharmaceutics classification system (BCS) class II that are weakly dissolved in water but have a good penetrating ability.⁵⁵ 

The nail plate is a tough, extended and bent framework used to protect the phalanx bones at the tips of the fingers and toes that are more prone to fractures as they are fragile and small. On the formation of newer nails, lanulae force the already grown nails to the higher and exterior side of the skin and on maturation of these new nail cells, they appear transparent. Various forms of nanotechnology are now being widely used for nails: (i) nanoencapsulation strategies including nanoliposomes, vesicles that conduct and circulate fluids having a double layer of lipid on the surface and formed by the discharge of phospholipids, generally regarded as safe (GRAS) products to carry necessary ingredients into the nail foldings; (ii) niosomes, unionized surface active agents being better carriers for weakly consumed ingredients, but not considered under GRAS due to dermatotoxicity; (iii) solid lipid nanoparticles, which protect the ingredients from disintegration for a longer period of time; and (iv) nanostructured lipid carriers, which are more spacious and allow the collection of extra ingredients over the nail folding.⁵⁶ 

Anthocyanins, derived from the Greek word ‘anthos’ meaning flower and ‘kyneous’ meaning dark blue tint, represent a major group of chemical substances obtained from plants, fruits and vegetables that are biologically active but not nutritive. They are particular dyes that have a phenolic nature and are soluble in water. They are able to provide a massive collection of various colors from red to purplish blue and hence play the part of native colorants having demand in the food, pharmaceutical and cosmeceutical industries. The cosmetic formulations possessing anthocyanins are efficient for the extraction of melanin and reduce the formation of reactive oxygen species of skin cells that produce keratin and fibroblasts that develop connective tissues. Many cosmeceutical companies such as Nivea®, Oriflame and L’Oreal follow the strategy of using derivatives of anthocyanins in their products.⁵¹ 

The formulation of lip care products primarily involves different oils and waxes for the prophylaxis and treatment of conditions such as dryness and roughness of the lips. The main reason for the lips getting dry and rough involves the shortened moisture holding capacity of the stratum corneum and feeble barrier function. Thus, to assess the degree of moisturization, lip skin penetration, lip hydration, dryness of the lips, stratum corneum barrier function, etc., a tri-method approach of three different lipids, such as berry fruit wax, coconut oil and olive oil, was carried out using the technique of confocal Raman spectroscopy (CRS), corneometry (skin capacitance) and trans-epidermal water loss (TEWL). The berry fruit wax, coconut oil and olive oil are thus considered as the active demulcents in this formulation. The proportion of olive oil was found to be 5–10 µm deep through the lip skin surface for 6 h after the application of the product, which on comparison with coconut oil and berry fruit wax was 5–10 µm for 2 h after product application. TEWL was curtailed and skin hydration was boosted for 2 h after product application. An improvement was seen during the ocular interpretation of soreness, roughness and tearing of the lip skin surface for 2 h after product application. From the above parameters, a definite conclusion was made that olive oil had the maximum efficacy, since its effect was observed after up to 6 h of product application. Hence, the tri-method study is authentic and compatible for the administration of all the three lipids in the stratum corneum of the lips.⁵⁷ 

Nowadays, an appeal for elements of natural origin and organic ingredients has been constantly surging. So, there has been extreme demand for the use of naturally acquired dispersing agents in the formulation of the cosmetics dealing with lip care, i.e. lipsticks. Recently, castor oil, octyldodecanol and meadowfoam seed oil have been studied as dispersing agents for lipsticks made up of Red 7 Lake powder and it was revealed that castor oil had the highest viscidity and retention rate among the others. Meanwhile, the lipstick containing meadowfoam seed oil was found to have moderate solid nature and gentle creaminess, suggesting its suitability as a dispersing agent.⁵⁸ 

The properties of lipsticks, such as their composition, consistency, rigidness and melting point, can be modified by changing the amount and quality of elements used in the formulation. An experiment was carried out by D-optimal mixture design, which is one of the most efficient and impressive means of resolving the problem of escalation associated with lipsticks. During the study, this method was used to escalate the liquefaction point of organic lipstick considering components like pitaya seed oil, virgin coconut oil, beeswax, candelilla wax and carnauba wax. D-optimal mixture design is generally used to analyze the number of individual variables together with a focus on the physical properties of the formulation. On performing the D-optimal analysis, the proportion of pitaya seed oil and virgin coconut oil had a reduced effect on the liquefaction point, whereas increasing the proportion of beeswax boosted the liquefaction point. An appropriate lipstick formulation holds a liquefaction point in the range of 40–56 °C, and on experimentation it was detected to be 46 °C, which matched the theoretical value of 46.5 °C.⁵⁹ 

In general, perspiration is released in the armpit and it is without any type of smell. The usual underarm smell is released from non-aromatic particles that are present in the exocrine glands and ooze out due to active Corynebacteria (mainly) and Staphylococcus species. Studies by Schmid and co-workers involved the segregation of the axillary malodor releasing enzyme (AMRE) and its prior structure 3-methyl, 2-hexanoic acid, both of which help to activate the smelling parameters from the discharge of non-aromatic armpits.⁶⁰ These segregates were developed and cultivated under suitable conditions and were then altered with the salt of carbamic acid and further split by zinc-dependent aminocyclase into scented ethanol along with glutamine that attenuates the passing out of the foul smell and additionally covers it with a floral one. Thus, this study has two purposes: (i) assessment of the process that controls the foul smell of cosmetic products, by segregation of corynebacteria; and (ii) alteration in the formation of prior foulness with aromatic particles.

Natural products aim to avoid any potentially harmful ingredients in products applied to the skin, but some are toxic and allergenic in nature. For instance, terpenes that are used predominantly in fragrances may cause liver toxicity in humans.⁶¹ Limonene and linalool, used as cleaning agents, detergents and deodorants, cause allergies and irritation in their oxidized state.⁶² Tea tree oils used in the preparation of cosmetic products cause dermatitis on the eyelids, hands and face when using soap, cream, shampoo, body lotion, and shaving cream containing tea tree oil.⁶³ Cinnamic acid used in perfuming, masking agents and skin conditioning causes allergies when used in excess amounts.⁶⁴ Caffeine is used in the preparation of various creams and lotions. A concentration of caffeine above 15 mg L⁻¹ causes neurodegenerative disorders, irritability and nervousness, and this can even lead to antagonism of aminobutyric acid, which can result in seizures.⁶⁵ Berberine, a component in Coptis japonica used as an anti-oxidant and anti-wrinkle agent, causes skin conditions like swelling, sagging, etc.⁶⁶ Kaempferol, used in skin care products having anti-collagenase and anti-tryrosinase activities, shows mutagenic as well as carcinogenic effects because of the conversion of Kaempferol to quercetin.⁶⁷ Propolis is a bee product that possesses anti-oxidant, antimicrobial and regenerative properties, but propolis ingestion may result in allergies, stomatitis, labial edema, and oral pain.⁶⁸ 

Cosmeceuticals are biologically active components that exhibit cosmetic as well as pharmaceutical benefits. Natural components exhibit various cosmeceutical properties, such as anti-oxidant, anti-aging, anti-wrinkle, anti-acne, skin lightening, hair smoothening, emulsifying, surfactant etc., and are tremendously increasing in market demand. In this chapter, the importance of natural products for the production of natural cosmeceuticals has been discussed. Although natural products for cosmetic uses have been widely explored, there is still a lot to explore in nature in order to obtain more components that may be formulated in cosmetic formulations. During their consideration, allergic responses should be studied in detail to prevent allergic responses. Amendments to the regulations are needed in order to fulfil the costumer’s demand for safe and effective cosmeceuticals.