Knowledge Base
Although less popular than o/w emulsions, these systems may be desirable when greater release of a medicating agent or the perception of greater emolliency is desired. Emulsifiers having an HLB range of 2.5 to 6 are frequently selected. When multiple emulsifiers are used, the predominant one is generally lipophilic with a smaller quantity of a hydrophilic emulsifier. These emulsions typically have a total of 45 to 80% oil phase.
Nowdays, formulators have become interested in more elegant w/o emulsions. This has been achieved by formulating with new emulsifying agents, emollient such as esters, Guerbet alcohols, and silicones. Selection of a suitable emollient depends on ability of the material to spread on skin with low tack, dermal compatibility, and perceived elegance by the user. In achieving this elegance, some researchers suggest a correlation of emollient and molecular weight of the emollients. In these studies, viscosity of w/o creams has correlated with molecular weight of the emollients used in test formulations.
High–molecular-weight co-emulsifiers formulated with high–molecular-weight emollients gave more stable w/o emulsions. The polarity of the emollients used was found to be important as well.
Emollients or mixtures of emollients with medium polarity gave test lotions the most desirable stability results. Anionic emulsifiers are generally inefficient w/o emulsion stabilizers, because more surface active agents are often needed to stabilize these emulsions. Sorbitan stearates and oleates are effective emulsifiers when
used at 0.5 to 5.0% sorbitan isostearates, being branched chain materials, give a very uniform particle size for w/o emulsions.
Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach
Vitis Vinifera (Grape) Seed Extract. Grape seed extract is derived from the small seeds (and occasionally the skins) of red grapes--the same kind that are pressed to make wine. Used extensively in Europe, grape seed extract is rich in flavonoids, phytochemicals that have antioxidant properties some consider even greater than the old standbys vitamin C and vitamin E. Antioxidants are believed to prevent and control numerous ailments by safeguarding cells against free radicals. The main benefit of grape fruit seed extract comes from proanthocyanidins. There are no adverse effect expected from the topical application of this extract. [CAS: 84929-27-1; EINECS: 284-511-6]. Function: Skin protecting.
Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data.
The physical quantity ‘viscosity’ gives information on how thick a fluid is and how easily it flows. In scientific terms, viscosity is the measure of a fluid’s internal flow resistance. It is the resistance which a fluid shows when being deformed.
In order to determine a fluid’s viscosity, you have to enter the field of viscometry, a subject area of a wider science called rheology. Rheology deals with the flow behavior and deformation of materials.
Imagine all materials as classified on a virtual scale from solid to liquid. Scientists specify solid materials as being elastic and liquids as being viscous. In everyday life, we mostly come across viscoelastic materials. That is, substances which are neither completely elastic, nor entirely viscous. According to a material’s properties, we either classify it as a viscoelastic solid (like e.g. sweet jelly) or as a viscoelastic liquid (like e.g. a yoghurt drink or shower gel).
The specific field of viscometry covers ideally viscous fluids, and – considering certain restrictions – also viscoelastic liquids, i.e. viscous fluids that contain an elastic portion. Fluids which flow easily show a low resistance to deformation. They are low-viscosity fluids. High-viscosity fluids resist deformation. Consequently, they do not flow easily.
What influences flow behavior?
- The substance's molecular structure
- The shear rate
- External conditions, like temperature or pressure
The dimensions of dynamic viscosity are force × time ÷ area. The unit of viscosity, accordingly, is newton-second per square metre, which is usually expressed as pascal-second in SI units.
Source: Official website of Anton-Paar and Britannica.com
Waxes are a mixture of hydrophobic organic substances of medium-chain length. Waxes will melt at temperatures in the range of 40°C up to 140°C without decomposition and will re-solidify unchanged. Solubility and consistency of waxes is strongly temperature-dependent. Waxes are classified into animal, vegetable and mineral types depending on their source.
Source: Cosmetic Formulation Principles and Practice - Heather A.E. Benson, Michael S. Roberts, Vânia Rodrigues Leite-Silva, Kenneth A. Walters
Formulation is a mixture of ingredients prepared in a certain way and used for a specific purpose. A cosmetic formulation is the combination of ingredients that make up a cosmetic product. The formulation is responsible for the product's performance, appearance, and shelf life.
The ingredients in a cosmetic formulation can be divided into two main categories: active ingredients and inactive ingredients. Active ingredients are the ingredients that provide the product with its desired effect, such as moisturizing, exfoliating, or protecting the skin. Inactive ingredients are the ingredients that help to improve the product's performance, appearance, or shelf life, such as thickeners, preservatives, and fragrances.
The goal of cosmetic formulation is to develop safe, effective, and appealing products that meet consumer needs while adhering to regulatory guidelines and quality standards in the cosmetics industry.
Undaria Pinnatifida Extract is an extract of the Alga, Undaria pinnatifida, Alariaceae. Undaria pinnatifida. Sea Mustard, Wakame, Japanese Kelp. The algae has resistance against harsh environmental stress (UV light, water movements and abrasions) that is related to its content of a special sulphated polysaccharide called fucoidan that protects the algae’s body wall from losing integrity and stability. It contains proteins, lipids, micronutrients, vitamins and sugar that lead to a revitalizing and energizing action on skin cells. It has been reported that fucoidan has radical scavenging and hyaluronidase inhibitory properties. It is these properties that make Wakame a useful antiaging active ingredient in cosmetics. Supplier: Crodarom produces a glycerin/aqueous extract of U. pinnatifida (Phytessence Wakame) and has shown that the protection of hyaluronic acid degradation by inhibition of hyaluronidase enzyme activity prevents deterioration of skin tissues, decrease of dermal thickness and improved firmness.
Source: Dweck, Anthony. Handbook of Cosmetic Ingredients: - their use, safety and toxicology (Dweck Books 5)
Sea mustard, Wakame, Japanese Kelp. The algae has resistance against harsh environmental stress (UV light, water movements and abrasions) that is related to its content of a special sulphated polysaccharide called fucodian that protects the algae's body wall from losing integrity and stability. It contains proteins, lipids microturients, vitamins and sugar that lead to a revitalizing and energizing action on skin cells. It has been reported that fucodian has radical scavenging and hyaluronidase inhibitory properties. It is these properties that make Wakame a useful antiaging active ingredient in cosmetics.
Source: Handbook Of Natural Ingredients - Anthony C. Dweck
Unique Selling Point or Unique Selling Proposition is a marketing term that describes the one thing that makes your product or service different from the competition. It is what makes your product or service special and worth buying.
A good USP should be:
Clear and concise
Believable
Persuasive
Relevant to the target audience
TEWL stands for transepidermal water loss. It is the amount of water that evaporates from the outermost layer of the skin (the stratum corneum) to the surrounding environment. TEWL is a natural process, but it can be increased by certain factors, such as dry air, hot weather, and harsh soaps.
TEWL is measured in grams per square meter per hour (g/m2/h). Normal TEWL rates range from 2.3 to 44 g/m2/h. However, TEWL can be higher in people with dry skin, eczema, or other skin conditions.
From the classic experiment by Pinson in 1942, comparing insensible perspiration from the skin on contralateral body sites with and without sweat glands inactivated by formaldehyde to our modern-day evaluations of skin-surface water evaporation, TEWL is taken as a true reflection of SC barrier function only when there is no sweat gland activity and the skin surface is dry.
This is achieved by conducting measurements in controlled temperature and humidity environments, typically 21°C, 50% relative humidity (RH) with subjects at rest. Basal or baseline TEWL is the resting rate of evaporative loss of water through normal nonperturbed skin. Although variation is observed from one body site to another, basal TEWL is low in normal healthy intact human skin. Basal TEWL is a primary end point used to dimension the variability in skin barrier function across age, body site, ethnicity, and other factors. Although in vitro evidence has challenged the validity of the assumption that TEWL is predictive of the skin’s permeability to topical penetrants more recent validation studies support the generally agreed conclusion that TEWL is the current best objective measure of the skin’s barrier to evaporative water loss.
The three instruments most commonly used to noninvasively measure TEWL are the Tewameter® evaporimeter (Courage & Khazaka, Cologne, Germany), the Dermalab TEWL module (Cortex Technologies, Hadsund, Denmark), and the ServoMed® evaporimeter (Servomed, Varberg, Sweden).
Source: Dermatologic, Cosmeceutic and Cosmeticdevelopment - Kenneth A. Walters, Michael S. Roberts
Amphoteric surfactants are amino acid derivatives; their net charge varies with the pH in solution. At pH below the isoelectric point they are positively charged in aqueous solution and can consequently adsorb more easily onto the skin. Alkyl chain length can also significantly act on the skin feel; some betaines based on C16/C18 cuts provide more greasy, refattened feel but also have detrimental effect on foam. Polydimethylsiloxane grafted with a betaine moiety leads to an amphoteric surfactant combining substantivity, refattening properties as well as silicone typical skin feel profile.
Some nonionics are used for their emollient properties and excellent afterfeel; e.g., sucrose and methyl glucose esters as well as sucrose ethers. Fatty acid alkanolamides are often referred to as refatteners; these are not lipids but they confer a greasy slippery feel to the foam and impart a particular afterfeel on the skin that subjectively compares with refatting. Several mild anionic surfactants are known to provide improved skin feel (afterfeel) by themselves, e.g., sarcosinate, taurate, acylglutamate, and isethionate. Fatty acids–protein condensates salts also act as conditioning aids, imparting a pleasant, smooth feel to the skin. The inclusion of fatty acids in soap and syndet bars contributes to enhance skin feel during and after use, and produces creamier lather. Phosphoric acid fatty esters deliver soap-like skin feel: slipperiness during use, and very good rinseability leaving skin feeling ‘‘clean’’ and powdery.
Benefits brought by additional skin conditioning agents are sometimes hidden by a mild or very mild cleaning-surfactant system delivering by itself very good skin feel properties; the sensorial baseline is high to start with and the increment in performance brought by skin feel agent is leveled off, and sometimes not even perceivable. It is, however, important to notice that several mild anionic and most of the nonionic surfactants, if they provide a pleasant afterfeel, are characterized by a ‘‘water feel’’ (feel in solution) that is often unpleasant, with rough and drag feel sensations.
Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach
The use of rheological additives such as clays, plant exudates, and natural polymers, to formulate personal-care products dates back to ancient times. These rheological additives are used to thicken the fluid, suspend dispersions of additives in the fluid, and improve the stability of the ensuing dispersion or emulsion as a function of temperature and shear history. An attempt will be made in this chapter to classify the wide array of rheological additives with respect to the actual function they serve in the final product.
Water and oils form the base fluids in which most personal-care and cosmetic products are formulated. These base fluids are generally classed as viscous or Newtonian fluids in that they possess a characteristic viscosity that is independent of the imposed rate of deformation. Newtonian fluids are also viewed as ideal fluids, in that they flow readily when subjected to very low deformations.
Non-Newtonian fluids on the other hand possess viscosities that are dependent on the rate of deformation and may exhibit other properties such as elasticity, yield stress, and thixotropy not seen in Newtonian fluids.
Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach
Suspensions are not just vehicles but products consisting of particles, generally actives or functional excipients, that are dispersed in a liquid or semisolid medium that functions as a vehicle. Nevertheless, a suspension is also a type of formulation that may be used for application on the skin and to deliver substances to a target. In this way, a suspension can be regarded as a vehicle entity affecting the application site. Examples are sun-protection products or pearlescent nail lacquers containing pigments.
In suspension, sedimentation of unsoluble particles may happen because of difference in density. In order to guarantee a homogeneous product when applied, the particles must be redispersible by shaking before use. Alternatively, sedimentation must be hindered or at least reduced during storage. This is achieved by reduction of particle size and/or by increasing the viscosity of the vehicle, ideally creating a thixotropic system. The vehicle effect of the suspension on the skin is primarily caused by the liquid or semisolid phase of the vehicle comparable to solutions and emulsions.
Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach
A tagline is a short phrase that captures a company's brand essence, personality, and positioning, and distinguishes the company from its competitors. Deceptively simple, taglines are not arbitrary. They grow out of an intensive strategic and creative process.
Taglines have become shorthand for what a brand stands for and delivers. Originally used in advertising as the centerpiece of a global marketing campaign, taglines historically have had much shorter life spans than logos. The best taglines have a long life, and transcend marketplace and lifestyle changes. They are meaningful and memorable, and require frequent and consistent use.
Source: Designing Brand Identity - Alina Wheeler
Stearic acid is a natural fatty acid which occurs in both animals and plants. Many suppliers only use the vegetable-derived source of this wax. It forms the basis of many lotions and emulsions, and helps to protect the skin against moisture loss. It can be made to form a soap in situ with triethanolamine or sodium hydroxide, which helps to keep the oil and the water in the emulsion from separating. The Food and Drug Administration (FDA) includes Stearic Acid on its list of direct food additives considered Generally Recognized As Safe (GRAS). Stearic Acid is also permitted as a direct food additive in chewing gum base. The FDA also includes fatty acids on its list of food additives permitted for direct addition to food. The safety of Stearic Acid, Lauric Acid, Myristic Acid, Oleic Acid and Palmitic Acid has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data concluded that these ingredients were safe for use in cosmetic products. STEARIC ACID. [CAS: 57-11-4; EINECS: 200-313-4]. Function: Emulsifying/ emulsion stabilising/ refatting/ cleansing.
Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data.
A stick is a solid delivery vehicle cast in an elongated form. By rubbing a stick onto skin, a variety of cosmetic ingredients can be delivered, such as fragrances, coloring agents, and emollients. In particular, sticks are ideally suited to deliver insoluble substances, e.g., pigments.
The most popular cosmetic sticks are lipsticks and antiperspirant/deodorant sticks.
There are mainly three basic vehicle types of sticks:
1. Mixture of waxes (e.g., beeswax, carnauba) and oils (e.g., mineral, castor oil) that are cast into solid form, containing dissolved or undissolved active ingredients
2. Hydrophilic or aqueous sticks: solutions based on aqueous, propylene glycol, alcohol mixtures, solidified usually by sodium stearate, containing, e.g., aluminium chlorohydrate as antiperspirant
3. Matrix consisting of a high-boiling volatile silicone (e.g., cyclomethicone) gelled by fatty alcohol (e.g., stearyl alcohol)
In recent years, clear sticks have become popular. As a gelling agent, dibenzylidene sorbitol is used in propylene glycol or other related polyols.
Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach
Stakeholders can be individuals, groups, or organizations that may affect, be affected by, or perceive themselves to be affected by a decision, activity, or outcome of a portfolio, program, or project. Stakeholders also directly or indirectly influence a project, its performance, or outcome in either a positive or negative way.
- Stakeholders influence projects, performance, and outcomes.
- Project teams serve other stakeholders by engaging with them.
- Stakeholder engagement proactively advances value delivery.
Stakeholders can affect many aspects of a project, including but not limited to:
▶ Scope/requirements, by revealing the need to add, adjust, or remove elements of the scope and/or project requirements;
▶ Schedule, by offering ideas to accelerate delivery or by slowing down or stop delivery of key project activities;
▶ Cost, by helping to reduce or eliminate planned expenditures or by adding steps, requirements, or restrictions that increase cost or require additional resources;
▶ Project team, by restricting or enabling access to people with the skills, knowledge, and experience needed to deliver the intended outcomes, and promote a learning culture;
▶ Plans, by providing information for plans or by advocating for changes to agreed activities and work;
▶ Outcomes, by enabling or blocking work required for the desired outcomes;
▶ Culture, by establishing or influencing—or even defining—the level and character of engagement of the project team and broader organization;
▶ Benefits realization, by generating and identifying long-term goals so that the project delivers the intended identified value;
▶ Risk, by defining the risk thresholds of the project, as well as participating in subsequent risk management activities;
▶ Quality, by identifying and requiring quality requirements; and
▶ Success, by defining success factors and participating in the evaluation of success.
Stakeholders may come and go throughout the life cycle of the project. Additionally, the degree of a stakeholder’s interest, influence, or impact may change over time. Stakeholders, especially those with a high degree of influence and who have an unfavorable or neutral view about a project, need to be effectively engaged so that their interests, concerns, and rights are understood. The project team can then address these concerns through effective engagement and support leading to the probability of a successful project outcome.
The Standard For Project Management And A Guide To The Project Management Body Of Knowledge (Pmbok® Guide) Seventh Edition
Acer Saccharum is a species of maple native to the hardwood forests of northeastern North America.The Sugar Maple is one of the most important Canadian trees, being, with the Black Maple, the major source of sap for making maple syrup, although Sugar Maple is regarded as slightly better. In addition to providing maple syrup, its extract behaves similarly to tannins, plant-based compounds that trigger protein production and have healing, soothing and toning properties and water-binding abilities which provide the skin with renewing, hydrating and texture-improving benefits. It is therefore used in a wide variety of cleansers, masks and moisturisers, including those for ageing, oily and also sensitive skins. Sugar Maple has mild astringent properties and has been used to make a wash for skin problems and eye wash for sore eyes. The inner bark of the tree, containing the sweet sap, can be used as a dressing for wounds. (CAS: 91770-22-8/EINECS: 294-807-7)
The shelf life is the period during which the manufacturer has determined a cosmetic or personal care product to be best suited for use.
No regulations or requirements under current U.S. law require manufacturers to print specific expiration dates on the labels of cosmetics and personal care products. However, they are required to determine shelf life as part of their responsibility to substantiate safety.
In Europe, cosmetics products with a lifespan longer than 30 months must show a “period-after-opening” (PAO) time. PAO is the time, recorded in months, when the product will remain in good condition after the consumer has used it for the first time. A symbol of an open cream jar is usually used instead of words with the PAO alongside or inside the symbol. Although this symbol can be found on some U.S. cosmetics and personal care products, it is not required.
Any cosmetic or personal care product in Europe with a lifespan of fewer than 30 months must show a “best-before-the-end-of” (BBE) date. The lifespan is usually shown using the “egg timer” symbol followed by the date or with words abbreviated as BBE or Exp, followed by the date. Very few products are labeled with BBE dates because most are known to last more than 30 months.
Some products do not require any of these because the product will not deteriorate during normal use. Examples are aerosols, which are effectively sealed; perfumes with high alcohol content; or single-use packs.
Consumers should be aware that expiration dates are “rules of thumb.” Like food, product quality may decline before the expiration date without proper storage. Products that have been improperly stored (e.g., exposed to high temperatures or sunlight or opened and examined by consumers before final sale) may deteriorate substantially before the shelf life or expiration date.
Source: https://www.cosmeticsinfo.org/
Cosmetic products play a significant role in our daily lives, helping us look and feel our best. Ensuring the safety of these products is of greatest importance and one crucial aspect of the process is the assessment of Systemic Exposure Dose (SED).
What is the Systemic Exposure Dose (SED)?
The Systemic Exposure Dose, abbreviated as SED, is a fundamental concept in toxicology and risk assessment and it refers to the amount of a cosmetic substance expected to enter the bloodstream. It is obtained by combining the external exposure (mg/kg bw/day) with the absorption rate (typically expressed in % or μg/cm2), frequency of application and retention factors and it is expressed in mg/kg body weight/day.
Why does SED matter in cosmetic safety evaluation?
In the context of cosmetics, the SED helps determine the potential health risks associated with the use of certain ingredients. It is essential to assess the SED of cosmetic ingredients to ensure they do not pose any harm when applied to the external parts of the human body (epidermis, hair system, nails, lips and external genital organs) or the teeth and the mucous membranes of the oral cavity.
Factors Influencing SED in Cosmetics
The following factors can influence the SED of cosmetic ingredients, including:
Ingredient physicochemical properties: The chemical composition, size, and solubility of an ingredient can affect its ability to penetrate the skin and enter the bloodstream.
Frequency and duration of use: The more often a cosmetic product is used and the longer it stays on the skin, the greater the potential for increased SED.
Ingredient concentration: The concentration of an ingredient in a cosmetic product plays a significant role in SED assessment. Higher concentrations are more likely to result in greater systemic exposure.
Source: SCCS Notes of guidance for the testing of cosmetic ingredients and their safety evaluation
The purpose of stability testing cosmetic products is to ensure that a new or modified product meets the intended physical, chemical and microbiological quality standards as well as functionality and aesthetics when stored under appropriate conditions. Because the development cycle of cosmetic products is relatively short, and also, in order that the testing activity does not become economically disproportionate in view of the multitude of product launches each year, each manufacturer must have at their disposal tests that are adapted to their activity. Each manufacturer should design their stability testing program such that it is reasonable and efficiently addresses the testing required. (Guidelines on stability testing of cosmetic products - Colipa)
The specific tests performed during stability testing will vary depending on the type of cosmetic product, but they typically include:
- Physical tests: These tests measure the appearance, texture, and color of the product.
- Chemical tests: These tests measure the concentration of ingredients in the product and the presence of any harmful substances.
- Microbiological tests: These tests measure the number of bacteria and other microorganisms in the product.
Stability testing is typically conducted over a period of several months or even years, and the product is tested under a variety of conditions, such as different temperatures, light levels, and humidity levels. The results of stability testing are used to determine the shelf life of the product, which is the length of time the product can be stored and still meet its intended quality standards.
Stability testing is an important part of the development and marketing of cosmetic products. It helps to ensure that consumers are using safe and effective products that will not deteriorate over time.
In the development of cosmetic products, it is crucial to introduce the laboratory sample into production settings to ensure its safe and consistent manufacturing. This process involves the scale-up phase, where progressively larger batch sizes are employed during pilot productions. This ensures that the final product replicates the characteristics of the sample created during product development.
Scaling up can be done by increasing the size tenfold or up to twenty times. For instance, if a 100-gram sample is produced, the next step would be a one-kilogram sample, followed by a 10-20 kg batch, and finally, the final production size.
Pilot productions are also necessary to mitigate risks. If a sample fails to yield the same results as the previous one, production can be repeated to ensure consistent quality. This risk reduction is achieved by identifying and rectifying issues early on in the process.
During the scale-up process, the physical parameters and stability of the sample must be thoroughly examined.
Scaling up is most efficient when different sized equipment utilizes the same technology.
Measurement uncertainty can also introduce variability into the final product. With small batches, even highly precise scales can yield significant deviations. This variability can be eliminated through the scale-up process.
Upon completion of the scale-up process, the final batch size, production documentation, and physical parameters are established. This allows for the product's introduction into mass production and the evaluation of manufacturing quality.
Additional Points:
The scale-up process should be documented in detail to ensure consistency and reproducibility.
Analytical testing should be conducted throughout the scale-up process to monitor product quality.
Any deviations from the expected results should be investigated and resolved promptly.
A well-defined scale-up process is essential for ensuring the successful transition of cosmetic products from lab to market.
A schedule is a model for executing the project’s activities, including durations, dependencies, and other planning information. Schedule planning can use predictive or adaptive approaches.
Predictive approaches follow a stepwise process as follows:
▶ Step 1. Decompose the project scope into specific activities.
▶ Step 2. Sequence related activities.
▶ Step 3. Estimate the effort, duration, people, and physical resources required to complete the activities.
▶ Step 4. Allocate people and resources to the activities based on availability.
▶ Step 5. Adjust the sequence, estimates, and resources until an agreed-upon schedule is achieved.
If the schedule model does not meet the initial desired end date, schedule compression methods are applied.
The Standard For Project Management And A Guide To The Project Management Body Of Knowledge (Pmbok® Guide) Seventh Edition
Saponins are glycoside compounds that are often referred to as natural detergents because of their ability to form foaming solutions in water. The majority of naturally occurring saponins are of the triterpenoidal type, with the steroidal based saponins forming a much smaller class. The steroidal saponins are based on a backbone of a (C30) triterpenoid saponin nucleus attached via C3 and an ether bond to a sugar side chain, whereas the steroidal are based on a choline (C27) steroid backbone. The aglycone of the triterpenoidal derivative is known as a sapogenin, whereas the steroidal aglycone derivatives are known as saraponins.
The non-saccharide portion (aglycone) of the saponin molecule is called the “genin” or “sapogenin”. Saponins are divided into three main classes depending on the type of sapogenin present:
- Triterpene glycosides - there are over more than 350 sapogenins and more than 750 triterpene glycosides in the triterpene glycoside class.
- Steroid glycosides
- Steroid alkaloid glycosides
The ability of a saponin to foam is caused by the combination of the non-polar sapogenin and the water-soluble side chain present on the molecule. The foams tend to be stable and have been used in fire extinguishers as the foaming agent. They are also used to produce foam in beer and are responsible for the natural foam in root beer. They have been used as the foaming agent in toothpaste and are employed by local people where the plants occur as a shampoo and laundry detergent.
Typical soap plants include Yucca (Yucca schidigera), Soapwort (Saponaria officinalis), Soapbark (Quillaia saponaria), Soaproot (Chlorogalum pomeridianum) and Soapnut (Sapindus spp).
Source: Dweck, Anthony. Handbook of Formulating Natural Cosmetics (Dweck Books 1)
Rosmarinus Officinalis Water is an aqueous solution of the steam distillate obtained from the Rosemary, Rosmarinus officinalis L., Lamiaceae. Rosmarinus Officinalis (Rosemary) Extract, Rosmarinus Officinalis (Rosemary) Flower Extract, Rosmarinus Officinalis (Rosemary) Flower/Leaf/Stem Extract, Rosmarinus Officinalis (Rosemary) Flower Wax, Rosmarinus Officinalis (Rosemary) Leaf, Rosmarinus Officinalis (Rosemary) Leaf Oil, Rosmarinus Officinalis (Rosemary) Leaf Extract, Rosmarinus Officinalis (Rosemary) Leaf Powder, Rosmarinus Officinalis (Rosemary) Leaf Water and Rosmarinus Officinalis (Rosemary) Water are ingredients made from the herb, Rosemary (Rosmarinus officinals). When the ingredient name does not include a plant part, it means that the ingredient is made from the whole plant, rather than a specific plant part. In cosmetics and personal care products, Rosemary-derived ingredients are used in the formulation of a wide variety of product types, including shampoos, shaving products, skin care products, suntan products, bath products, makeup, cleansing products, hair conditioners, permanent waves, shampoos and personal cleanliness products. The Food and Drug Administration (FDA) includes Rosemary (Rosmarinus officinalis) on its list of spices and other natural seasonings and flavorings considered Generally Recognized As Safe (GRAS). Botanical and botanically-derived ingredients used in the formulation of cosmetics are generally mild and safe. Prior to marketing the finished cosmetic product, the safety of each ingredient must be substantiated in accordance with 21 CFR 740.10. Safety substantiation of cosmetic ingredients may include tests for ocular and skin irritation as well as allergenicity, phototoxicity, photoallergenicity and mutagenicity, depending on the application or intended use. There is a considerable body of information about the safety of botanical ingredients and a well established history of use. These resources are consulted to ensure the safety of these materials as they are used in cosmetics and personal care products..
Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data.
Rosa Damascena Flower Extract is an extract of the flowers of the Damask Rose, Rosa damascena, Rosaceae. Rosa damascena, called rose otto or attar of roses, is made by picking new blooms early in the morning before the oil and scent dissipates in the sun. Oil is extracted when the petals are steamed. Attar of roses has been used in cosmetics, lotions, and perfumes around the world for centuries, and the flowers can also provide a hint of colour in emollients. Rosa damascena sometimes called the Rose of Castile, is a rose hybrid, derived from Rosa gallica and Rosa moschata. DNA analysis has shown that a third species, Rosa fedtschenkoana, is associated with the Damask rose. The Damask rose is commonly used to flavor food and to make rose water. Rose extract and rose oil have a host of beneficial affects on the skin and are great for promoting a youthful complexion with good tone, elasticity and an even colored complexion. Toxicity class D acute oral, Dermal Irritation class C, Dermal sensitisation class D (2%). Rated safe during pregnancy, Mucous Membrane C-D (non-irritant). Not in the warning list for pregnancy.
Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data.
The term rheology describes the flow characteristics of liquids and the deformation of solids. Viscosity is an expression of the resistance of a fluid to flow. Rheological properties are crucial for liquid and semiliquid cosmetic formulations because they determine the product’s properties meaningful in mixing and flow when produced, filled into containers and removed before use, as well as sensory properties when applied, such as consistency, spreadability, and smoothness.
Furthermore, the rheology of a product may also affect the physical stability and the biological availability of the product. Regarding rheological characteristics, there are two main types of systems: Newtonian and non-Newtonian.
The former show constant viscosity when stressed, i.e., the rate of shear (flow velocity) is directly proportional to the shearing stress, e.g., water, mineral oil, etc. In non-Newtonian systems (most cosmetic products), however, viscosity changes with varying stress, i.e., viscosity depends on the degree of shearing stress, resulting either in plastic, pseudoplastic, or dilatant flow or in thixothropy, characteristics that are not discussed in depth here although they are of practical significance. An ideal topical product, e.g., shows optimal thixotropic properties; it does not flow out of a tube’s orifice unless slightly pressed, and when on the skin it does not immediately flow and drop off unless easily spread over the application area, where under a certain stress it becomes more fluid because of the thixotropy. The rheological properties of semisolid products are determined first for general characterization in the development phase and second for quality-control reasons after manufacturing. There are various instrumental methods used to measure rheology or viscosity. Today, apparatus based on rotation or oscillation are commonly used for non-Newtonian systems.
In order to adjust the rheology of products, various means and excipients are available. If the viscosity has to be increased, addition of viscosity increasing agents is needed. Addition or increase in concentration of electrolytes may influence viscosity. Many systems, e.g., polyacrylates, are sensitive to the presence of ions and the viscosity is reduced. In particular, emulsions are susceptible to rheological issues. Various factors determine the rheological properties of emulsions, such as viscosity of internal and external phases, phase volume ratio, particle size distribution, type and concentration of emulsifying system, and viscosity-modifying agents.
It is important to realize that small changes in concentrations or ratio of certain ingredients may result in drastic changes of the rheological characteristics. Emulsified products may undergo a wide variety of shear stresses during either preparation or use. Thus, an emulsion formulation should be robust enough to resist external factors that could modify its rheological properties or the product should be designed so that change in rheology results in a desired effect.
Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach
