Characterization and applications of biomacromolecule structurally similar to glycogen as a dispersion aid and skin protection agent

Glycogen is a naturally occurring or metabolically synthesized biological macromolecule found in a wide range of living organisms, including animals, microorganisms, and even plants. However, naturally sourced glycogen poses challenges for industrial use. This study focused on a biological macromolecule referred to as glycogen-like particles (GLPs), detailing the production methods and biological properties of these particles. In vitro enzymatic production of GLPs was successfully achieved. GLPs synthesized through a simultaneous enzymatic reaction using sucrose had significant changes in their structure and functionality based on the branching enzyme (BE) to amylosucrase (ASase) ratio. As this ratio increased, the GLPs developed higher molecular weights and greater density, solubility, and branching degree while reducing size and turbidity. Structural changes in these enzymes were not observed beyond a critical BE/ASase ratio. Uniformly dispersed curcumin powder was generated in 50 % (w/v) aqueous GLP solution, and the GLPs were non-toxic to human skin keratinocytes at a concentration of 2.5 mg/mL. GLPs with lower branching inhibited tyrosinase activity and melanin synthesis, while those with more long chains displayed effective UV-blocking. By manipulating the BE/ASase ratio, GLPs were shown to display diverse chemical structures and physical characteristics, suggesting their potential application in the food and cosmetics industries.

The potential cutaneous benefits of edible bird's nest

Edible bird's nest (EBN) is composed of the solidified saliva of swiftlet birds. EBN has been extremely popular in Asian culture for centuries. They are often consumed as a delicacy in the form of bird's nest soup and are believed to have numerous skin benefits. In light of EBN's growing popularity and significant cultural importance, we aim provide a comprehensive review of EBN's potential dermatologic benefits and role in photoaging, anti-inflammation, wound healing, skin barrier enhancement, and skin whitening. While in vitro, in vivo, and preliminary clinical trial results are promising, there is a need for future human clinical research to further validate these findings and establish EBN's efficacy and safety for dermatologic applications.

Enzyme-treated caviar extract ameliorates melanogenesis in UVB-induced SKH-1 hairless mice

This study investigated anti-melanogenesis effects of enzyme-treated caviar extract (CV) in murine melanoma B16F10 cells and SKH-1 hairless mice. To induce melanin production in vitro and in vivo studies, B16F10 cells were treated with 3-Isobutyl-1-methylxanthine (IBMX), and SKH-1 hairless mice were irradiated with UVB, respectively. The expression of melnogenesis-related factors and signaling molecules were analyzed by ELISA and western blotting. 50, 100 and 200 μg/mL of CV significantly decreased the melanin contents and the activities of tyrosinase, nitric oxide, glutathione, and cAMP, melanogenesis factor, in B16F10 cells treated IBMX. In addition, CV significantly suppressed the expression of melanogenesis proteins such as pPKA, pCREB, MITF, TRP-1and TRP-2. Similarly, results of oral administration of CV (20, 50 and 100 mg/kg) for 8 weeks in UVB-Induced SKH-1 hairless mice, the expression of melanogenesis-related factor tyrosinase, nitric oxide, and cAMP and protein expression of pPKA, pCREBa, MITF, TRP-1and TRP-2 was significantly reduced. In particular, 100 mg/kg of CV exhibited an excellent effect similar to control group. Therefore, we suggest the possibility of developing CV as a food supplement having skin whitening effects by ameliorating melanogenesis.

Biotransformation of ginsenoside Rb1 and Rd to four rare ginsenosides and evaluation of their anti-melanogenic effects

Improving physiological activity of primary ginsenosides through biotransformation is of great significance for food applications. In this study, gynostapenoside XVII, gynostapenoside LXXV, ginsenoside F2, and ginsenoside CK were obtained by enzymolysis of an accessible extract composed of ginsenoside Rb1 and Rd. Their effects on melanin content and tyrosinase activity were compared in vitro, and molecular docking simulation was employed to elucidate the interaction between tyrosinase and individual saponin. The results indicated that four rare ginsenosides decreased tyrosinase activity, melanin content and microphthalmia-associated transcription factor (MITF) expression level, more greatly than their primary ginsenosides, and they were more readily to bind with ASP10 and GLY68 at active site of tyrosinase to inhibit tyrosinase activity as well. These findings suggested that the rare ginsenosides obtained by enzymolysis had excellent anti-melanogenic effect, which could expand the application of ginsenosides in the field of functional foods and health supplements.

The anti-melanogenic properties of Swietenia macrophylla king

Fair flawless skin is the goal for some cultures and the development of irregular skin pigmentation is considered an indication of premature skin aging. Hence, there is a rising demand for skin whitening cosmetics. Thus, this research will be focusing on discovering the anti-pigmentation properties of Swietenia macrophylla seeds. Firstly, the seeds were extracted with ethanol and further fractionate based on their polarity before testing them on zebrafish embryos. The ethanolic extract of the seed demonstrated significant inhibition of both tyrosinase activity and melanin production in the embryos. However, after fractionation, the anti-melanogenic ability was observed to have decreased, signifying that the phytocompounds may be synergistic in nature. Still in the proteomic studies the ethanolic extract and its hexane fraction both induced the downregulation of cathepsin LB and cytoskeletal proteins that have connections to the melanogenic pathway, confirming that S. macrophylla seeds do indeed have anti-pigmentation properties that can be exploited for cosmetic use. Next, limonoids (tetranortriterpenoids found in the seed) were tested for their inhibitory effect against human tyrosinase related protein 1 (TYRP-1) via molecular docking. It was found that limonoids have a stronger binding affinity to TYRP-1 than kojic acid, suggesting that these phytocompounds may have the potential in inhibiting pigmentation. However, this still needs further confirmation before these phytocompounds can be developed into a skin whitening agent. Other assays like ex-vivo or 3D human skin culture can also be used to better study the seeds anti-pigmentation effect on humans.

The melanin inhibitory effect of plants and phytochemicals: A systematic review

BACKGROUND

Melanin plays an important role in protecting human skin, while excessive synthesis of melanin can cause abnormal pigmentation and induce skin diseases. Long-term use of commercial whitening agents in managing skin melanin such as kojic acid and arbutin can lead to some negative effects such as dermatitis and liver cancer. Although past studies have researched the melanin inhibitory effect of plant extracts, the effective dose and mechanisms are not well summarized and discussed. This study aims to explore the melanin inhibitory property of phytochemicals and tries to answer the following research questions: (1) Which plant extracts and phytochemicals could inhibit melanin biosynthesis in the skin? what is the mechanism of action? (2) Have human trials been conducted to confirm their melanin inhibitory effect? (3) If not, which phytochemicals are recommended for further human trials? This article would provide information for future research to develop natural and safe skin whitening products.

METHODS

A preferred reporting items for systematic reviews and meta-analyses (PRISMA) systematic review method and OHAT risk-of-bias tool were applied to screen literature from 2000 to 2021 and 50 research articles met the selection criteria.

RESULTS

Flavonoids, phenolic acids, stilbenes and terpenes are main classes of phytochemicals responsible for the melanin inhibitory effects. The in vitro/in vivo melanin inhibitory effects of these plant extracts/phytochemicals are achieved via three main mechanisms: (1) the ethyl acetate extract of Oryza sativa Indica cv., and phytochemicals such as galangin and origanoside could manage melanin biosynthesis through competitive inhibition, non-competitive inhibition or mixed-type inhibition of tyrosinase; (2) phytochemicals such as ginsenoside F1, ginsenoside Rb1 and 4‑hydroxy-3-methoxycinnamaldehyde could inhibit melanogenesis through down-regulating microphthalmia-related transcription factor (MITF) gene expression via different signalling pathways; (3) the ethanolic extracts of Dimorphandra gardneriana, Dimorphandra gardneriana, Lippia microphylla and Schinus terebinthifolius have a good ultraviolet absorption ability and high sun protective factor (SPF) values, thereby inhibiting UV induced melanogenesis in the skin.

CONCLUSION

Although many plant extracts and phytochemicals have been found to inhibit melanin production, most of the results were only proved in cellular and/or animal models. Only the ethyl acetate extract of Oryza sativa Indica cv. panicle, and ginsenoside F1 were proved effective in human trials. Animal studies proved the effectiveness of galangin, origanoside, ginsenoside Rb1 and 4‑hydroxy-3-methoxycinnamaldehyde with effective dose below 3 mM, and therefore recommended for future human trial. In addition, cellular studies have demonstrated the effectiveness of oxyresveratrol, mulberroside A, kurarinol, kuraridinol, plumbagin, (6aR,11aR)-3,8-dihydroxy-9‑methoxy pterocarpan, ginsenoside Rh4, cardamonin, nobiletin, curcumin, β-mangostin and emodin in inhibiting melanin synthesis at low concentrations of 20 µM and proved the low SPF values of Dimorphandra gardneriana, Dimorphandra gardneriana, Lippia microphylla and Schinus terebinthifolius extracts, and therefore recommended for further animal and human trials.

7-desacetoxy-6,7-dehydrogedunin discovered by high-throughput screening system suppresses melanogenesis through ATP-P2X7 signaling inhibition

BACKGROUND

Hyperpigmented skin disorders such as melasma and lentigo are common photoaging diseases that cause cosmetic problems. The pigmentation is usually exacerbated by ultraviolet (UV) radiation, and various factors and pathways are involved in UV-mediated melanogenesis. Adenosine 5'-triphosphate (ATP), a well-known molecular unit of intracellular energy, is also regarded as a mediator of UV-mediated melanogenesis via the P2X7 purinergic receptor.

OBJECTIVE

To discover natural substances with an anti-melanogenic effect through inhibition of ATP-P2X7 axis by high-throughput screening (HTS).

METHODS

Among natural compounds provided by the Korea Chemical Bank, chemical compounds with a P2X7 inhibiting effect were screened through an HTS system. Then the selected compounds were verified for their anti-melanogenic effect after treating primary human epidermal melanocytes (PHEMs) with and without ATP. The expression of MITF, tyrosinase, and PMEL/gp100 was analyzed by Western blot, and melanin content was measured as 405 nm absorbance.

RESULTS

Among 962 natural compounds, 58 showed greater than 80% suppression of YO-PRO-1 fluorescence, representing P2X7 activity. Among them, considering cell viability, chemical stability, and availability, 7-desaxacetoxy-6,7-dehydrogedunin (7DG), a limonoid natural compound, was selected. The expression of MITF, tyrosinase, and PMEL/gp100; tyrosinase enzyme activity; and melanin content, which were increased by ATP treatment were abrogated by 7DG. Even when 7DG was treated in PHEMs without addition of ATP, tyrosinase expression and melanin content were significantly decreased. Hypopigmenting effect of 7DG was confirmed in ex vivo culture of human skins.

CONCLUSIONS

7DG has an anti-melanogenic effect through ATP-P2X7 pathway inhibition and could be a potential skin whitening material.

Dermocosmetic applications of microalgal pigments

Among photosynthetic microorganisms, Cyanobacteria and Microalgae species have been highly studied thank to their high value-added compounds for several industrial applications. Thus, their production is increasing in the last decade to produce raw material for cosmetics. In fact, the daily routine includes the use of cosmetics and sunscreens to protect against the environmental changes, mainly the increment of ultraviolet (UV) radiation rate with a consequent skin damage and premature aging due to this overexposure. As it is well discussed, chemical UV filters are extensively incorporated into sunscreens formulas; however, they can induce allergenic reactions as well. For these reasons, some pigments derived from microalgae, such as astaxanthin, lutein, β-carotene as well as other biocompounds are now well described in the literature as well as biotechnologically manufactured as natural ingredients to be incorporated into skin care products with multifunctional benefits even for sunscreen purposes. Hence, this investigation summarizes the recent studies about the main pigments from photosynthetic microorganisms' biomasses as well as their uses in dermocosmetics with novel attributes, such as anti-aging agents, makeups, skin lightening and whitening, among others.

Unravelling property of polysaccharides from Sargassum sp. as an anti-wrinkle and skin whitening property

In recent years, the natural ingredients are in high demand in formulating the cosmetic products. Seaweed polysaccharides signify the attractive natural ingredient with a wide range of functional properties that are expected for cosmeceutical formulations. The present work aimed to study the skin protection ability of polysaccharides extracted from Sargassum vachellianum (SvP), Sargassum horneri (ShoP) and Sargassum hemiphyllum (SheP). The extracted crude polysaccharides were characterized by HPLC and FTIR, which revealed that the polysaccharides are fucose-containing sulfated polysaccharides. Skin whitening and anti-wrinkling activity were analyzed by the ability to inhibit tyrosinase and elastase. The results revealed that the ShoP showed maximum tyrosinase inhibition (64.72 ± 0.46%) and SvP exhibited considerable elastase inhibition (30.12 ± 0.33%). The maximum moisture absorption (79.7 ± 0.62%) and retention (68.99 ± 0.64%) ability were observed in ShoP. The antioxidant activity was estimated by DPPH, superoxide radical scavenging, reducing power and total antioxidant activity. All the tested polysaccharides showed antioxidant activity in a dose-dependent manner, among them ShoP exhibited maximum total antioxidant (80.93 ± 0.17%) and superoxide radical scavenging activity (67.4 ± 0.42%) whereas SheP showed maximum DPPH radical scavenging activity (74.56 ± 0.10%). Therefore, the present study indicates the potential of polysaccharides, ShoP, SvP and SheP as a promising cosmetic ingredient in cosmeceuticals.

Skin lightening practices, beliefs, and self-reported adverse effects among female health science students in Borama, Somaliland: A cross-sectional survey

Background

Skin-lightening (SL) products are common, especially in Africa. Adverse effects from these products represent a public health concern. Use of these products in Somaliland is unknown.

Objective

This study aimed to determine the prevalence of use of SL products among female health science students, beliefs about these products and practices, and adverse effects experienced.

Methods

This was a cross-sectional survey of a convenience sample of female health science students at Amoud University in Borama, Somaliland.

Results

Of the 400 students who were invited to participate, 265 completed the survey (response rate: 66%). Mean participant age was 21.1 years (standard deviation: 2.0 years). The majority of students were single (91.2%) with a Fitzpatrick skin type of 3 or darker (94.2%). Past or present use of SL products was reported by 25.6% of participants, and 52.2% admitted to current use. Compared with non-users, more SL product users agreed that lighter skin color gives a woman more confidence, helps a woman have better job opportunities, and increases chances of getting married. They also agreed that advertisements on television for SL products influence a women’s preference for a lighter skin tone (p < .05). More than 60% of participants were unsure what active ingredients were in their SL products. Only 9% denied any undesirable adverse effects, and the remainder reported an array of local and systemic adverse effects. The vast majority realize that SL products may cause undesirable local (92%) and systemic (89%) adverse effects.

Limitations

Generalizability is limited because a nonrandomized convenience sample from one university was studied. Response bias also may have skewed results.

Conclusion

Use of SL products among female health science students in Somaliland is common, and causes cutaneous and systemic adverse reactions. Use appears influenced by beliefs about the benefits of lighter skin color. Education is needed on the proper use of these products, how to avoid harmful products, and how to prevent complications.

Phenylethyl resorcinol smartLipids for skin brightening - Increased loading & chemical stability

Phenylethyl resorcinol (PER, 4-(1-phenylethyl)1,3-benzenediol) is a very potent tyrosinase inhibitor with clinically proven effectiveness at already 0.5%. A major challenge of incorporating PER into dermal products is its high sensitivity against light. Previously, by incorporating PER in nanostructured lipid carriers (NLC), chemical stability and tyrosinase activity could be increased by 29% and 67%, respectively. Despite this, degradation still occurred accompanied with reddish discoloration of the formulation - not acceptable for market products. In this study PER was incorporated into smartLipids, the 3rd generation of lipid carriers. Compared to NLC, the smartLipids formulation had a higher PER loading, was PEG-free and used ECOCERT-certified Lanette N. For PER stabilization, 14 additives from three groups were investigated: UV blockers, antioxidants and chelating agents. The UV blockers Tinosorb S and Oxynex ST liquid, as well as the chelating agents ethylenediaminetetraacetic acid and phytic acid completely prevented reddish discoloration under test conditions (3 months in the dark and 7 days at light exposure). Investigating the stabilizing mechanisms, UV absorbers with high absorption in UV-A range were most effective (Tinosorb S, Oxynex liquid). They showed good stabilization in dark and at light exposure. Chelating agents had mainly an effect via pH shift to pH 2, thus are not suitable for dermal products requiring pH around 5. Antioxidants were less effective. The antioxidants propyl gallate and BHT showed best stabilization at storage in dark and slightly less at light exposure, not impairing the physical stability. Some antioxidants even accelerated discoloration (e.g. Tinogard TT). In general, low standard electrode potential (<0.4 mV) seems to be favorable for PER stabilization. In conclusion, Tinosorb S proved to be the best stabilizer; combination with an antioxidant is optional. By combination of smartPearls technology and the Tinosorb S stabilization, PER market products without discoloration are feasible.

Antioxidant, anti-tyrosinase and anti-melanogenic effects of (E)-2,3-diphenylacrylic acid derivatives

During our continued search for strong skin whitening agents over the past ten years, we have investigated the efficacies of many tyrosinase inhibitors containing a common (E)-β-phenyl-α,β-unsaturated carbonyl scaffold, which we found to be essential for the effective inhibition of mushroom and mammalian tyrosinases. In this study, we explored the tyrosinase inhibitory effects of 2,3-diphenylacrylic acid (2,3-DPA) derivatives, which also possess the (E)-β-phenyl-α,β-unsaturated carbonyl motif. We synthesized fourteen (E)-2,3-DPA derivatives 1a-1n and one (Z)-2,3-DPA-derivative 1l' using a Perkin reaction with phenylacetic acid and appropriate substituted benzaldehydes. In our mushroom tyrosinase assay, 1c showed higher tyrosinase inhibitory activity (76.43 ± 3.53%, IC₅₀ = 20.04 ± 1.91 µM) with than the other 2,3-DPA derivatives or kojic acid (21.56 ± 2.93%, IC₅₀ = 30.64 ± 1.27 μM). Our mushroom tyrosinase inhibitory results were supported by our docking study, which showed compound 1c (-7.2 kcal/mole) exhibited stronger binding affinity for mushroom tyrosinase than kojic acid (-5.7 kcal/mole). In B16F10 melanoma cells (a murine cell-line), 1c showed no cytotoxic effect up to a concentration of 25 μM and exhibited greater tyrosinase inhibitory activity (68.83%) than kojic acid (49.39%). In these cells, arbutin (a well-known tyrosinase inhibitor used as the positive control) only inhibited tyrosinase by 42.67% even at a concentration of 400 μM. Furthermore, at 25 µM, 1c reduced melanin contents in B16F10 melanoma cells by 24.3% more than kojic acid (62.77% vs. 38.52%). These results indicate 1c is a promising candidate treatment for pigmentation-related diseases and potential skin whitening agents.

Effective melanin degradation by a synergistic laccase-peroxidase enzyme complex for skin whitening and other practical applications

Melanin is major cause of dark skin, which is regarded as social status in eastern Asia. As a result, researchers in cosmetic industries are developing skin whitening agents. Melanin can be decolorized by many oxidative enzymes. Laccase (CueO) from Escherichia coli and dye-decolorizing peroxidase (DyP) from Bacillus subtilis were merged with the dockerin domain of endoglucanase B from Clostridium cellulovorans. Scaffoldin has great potential to exert structural benefits that enable complementary enzyme effects. The carbohydrate binding module (CBM) in scaffoldin was replaced with the melanin binding peptide (MBP) to increase melanin binding and thereby enhance melanin degradation. The modified scaffoldin exhibits a nearly 64% increase in specific binding to melanin over that of the native scaffoldin. Laccase was used to degrade melanin via the production of hydrogen peroxide, which produced synergistic activity with peroxidase. The activity of the optimized complex was approximately 6.4-fold greater than that of laccase alone. This enzyme complex can also reduce the number of melanin granules in corneocytes. Based on these results, a recombinant enzyme complex is suitable for use in melanin degradation by next generation whitening agents in the skin cosmetics industry.

Potential biomedical applications of marine algae

Functional components extracted from algal biomass are widely used as dietary and health supplements with a variety of applications in food science and technology. In contrast, the applications of algae in dermal-related products have received much less attention, despite that algae also possess high potential for the uses in anti-infection, anti-aging, skin-whitening, and skin tumor treatments. This review, therefore, focuses on integrating studies on algae pertinent to human skin care, health and therapy. The active compounds in algae related to human skin treatments are mentioned and the possible mechanisms involved are described. The main purpose of this review is to identify serviceable algae functions in skin treatments to facilitate practical applications in this high-potential area.

Tranexamic acid inhibits melanogenesis by activating the autophagy system in cultured melanoma cells

BACKGROUND

As interest in skin beauty increases, the development of new skin whitening agents has attracted substantial attention; however, the action mechanism of the agents developed so far remains largely unknown. Tranexamic acid (TXA) is commonly being used to reduce melanin synthesis in patients with melasma and also used as a raw material for functional whitening cosmetics, although its action mechanism is poorly understood. Autophagy has been well known to be essential for tissue homeostasis, adaptation to starvation, and removal of dysfunctional organelles or pathogens. Recent studies have shown that autophagy regulators might have prominent roles in the initial formation stage of the melanosome, a lysosome-related organelle synthesizing melanin pigments. However, there is still no direct evidence showing a relationship between the activation of the autophagy system and the melanogenesis.

OBJECTIVE

To investigate whether TXA can inhibit melanogenesis through the activation of autophagy in a melanoma cell line.

METHODS

B16-F1 melanoma cells were treated with TXA and the levels of autophagy- and melanogenesis-related proteins were determined by Western blottings. The direct effect of TXA-mediated autophagy activation on melanin production was further evaluated by transfecting the cells with 60 pmols of small interfering RNAs (siRNAs)-targeting the mechanistic target of rapamycin (mTOR) and the autophagy-related protein 5 (Atg5).

RESULTS

The results of Western blottings showed that TXA enhanced the production of autophagy-related proteins such as mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinase (ERK)1/2, Beclin-1, Atg12, and light chain 3 (LC3) I-II, whereas it decreased the synthesis of the mTOR complex. Confocal microscopy clearly showed that TXA treatment resulted in the formation of autophagosomes in B16-F1 cells, as revealed by immunostaining with an anti-LC3 antibody. The production of melanogenesis-associated proteins, including microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase-related protein 1 and 2 (TRP1/2), were clearly downregulated by the treatments with TXA. These results suggest that TXA can mediate a decrease in melanin synthesis by alleviating the production of tyrosinase and TRP1/2, along with lowered MITF protein levels. Furthermore, after treatment with TXA, siRNAs- targeting to mTOR and Atg5 increased melanin synthesis by 20% and 40%, respectively, compared to that in non-transfected cells, in a dose-dependent manner. These results further confirmed that TXA can inhibit melanogenesis by activating the autophagy system.

CONCLUSION

Collectively, the results demonstrate that TXA can reduce melanin synthesis in melanoma B16-F1 cells by activating the ERK signaling pathway and the autophagy system.

Synthesis and biological evaluation of caffeic acid derivatives as potent inhibitors of α-MSH-stimulated melanogenesis

We have disclosed our effort to develop caffeic acid derivatives as potent and non-toxic inhibitors of α-MSH-stimulated melanogenesis to treat pigmentation disorders and skin medication including a cosmetic skin-whitening agent. The SAR studies revealed that cyclohexyl ester and secondary amide derivatives of caffeic acid showed significant inhibitory activities.

Skin whitening among Cameroonian female university students: knowledge, attitudes, practices and motivations

Background

Lack of data on skin whitening (SW) among Cameroonian female university students prompted us to undertake the present study which aimed at assessing the knowledge, attitudes, practices and motivations of female university students vis-a-vis SW.

Methods

This was a cross-sectional study conducted from January to April 2013 in 4 university campuses of Yaoundé, Cameroon. Any female student regularly registered in one of the study sites, who was present at the campus when the investigator visited and volunteered to participate in the study was enrolled.

Results

Overall, we recruited 620 female students, their ages ranging from 16 to 46 years with a mean of 21.3 ± 2.9 years. Only 87 participants (14%) found that SW was a good practice. One hundred and sixty nine respondents (27.3%) were currently practicing SW with no age difference when compared to their counterparts (p = 0.09). The desire to have a uniform body skin color was the prevailing reason motivating the practice of SW (39.1%), followed by the need to have a soft skin (29%). Assessment of levels of knowledge regarding advantages of the black skin and deleterious effects of SW showed excellent scores (≥75% of good answers) only in 6.1 and 0.5% of cases respectively, with no difference between those practicing SW or not (all p values > 0.05).

Conclusion

The practice of SW is common among Cameroonian female university students who should therefore be educated on the advantages of the black skin and the harmful effects of SW.

Electronic supplementary material

The online version of this article (doi:10.1186/s12905-017-0385-z) contains supplementary material, which is available to authorized users.

Enzymatic synthesis of bioactive compounds with high potential for cosmeceutical application

Cosmeceuticals are cosmetic products containing biologically active ingredients purporting to offer a pharmaceutical therapeutic benefit. The active ingredients can be extracted and purified from natural sources (botanicals, herbal extracts, or animals) but can also be obtained biotechnologically by fermentation and cell cultures or by enzymatic synthesis and modification of natural compounds. A cosmeceutical ingredient should possess an attractive property such as anti-oxidant, anti-inflammatory, skin whitening, anti-aging, anti-wrinkling, or photoprotective activity, among others. During the past years, there has been an increased interest on the enzymatic synthesis of bioactive esters and glycosides based on (trans)esterification, (trans)glycosylation, or oxidation reactions. Natural bioactive compounds with exceptional theurapeutic properties and low toxicity may offer a new insight into the design and development of potent and beneficial cosmetics. This review gives an overview of the enzymatic modifications which are performed currently for the synthesis of products with attractive properties for the cosmeceutical industry.

Critical review of Ayurvedic Varṇya herbs and their tyrosinase inhibition effect

INTRODUCTION

The aspiration for light skin (fair complexion) is becoming pronounced in a greater number of people in the present times with natural products being more in demand than their synthetic counterparts. Research in the area of skin-lightening agents is an expanding field with the knowledge being updated regularly. In Ayurveda, varṇya, raktaprasādana, tvacya are few terms specifying skin lightening with respect to its modern counterpart i.e., Tyrosinase inhibition, the most commonly reported method of skin lightening.

AIM

The present review is undertaken for screening twenty herbs from Varṇya Mahākaṣāya, Lodhrādi varṇya gaṇa, Elādi varṇa prasādana gaṇa and few varṇya formulations to evaluate their probable modes of action through which the skin lightening is effected as per both Ayurveda and biomedical concepts.

MATERIALS AND METHODS

Critical review of herbs to show varṇya property is compiled from various Ayurvedic texts as well as from multiple articles on the internet to justify their skin lightening property on the basis of data collected.

RESULT AND CONCLUSION

All the twenty herbs reviewed are found to act as varṇya directly (citation as varṇya) or indirectly (alleviation of pitta and rakta) as per Ayurveda and to interfere in melanogenesis pathway through tyrosinase inhibition as per biomedicine. This shows their potential to act as good skin whitening agents. Śuṇṭhi being a part of many varṇya formulations, is the only herb among all reviewed in the present study found to exhibit tyrosinase inhibition without any Ayurvedic citation of varṇya property.

Phenolic Compounds from the Leaves of Stewartia pseudocamellia Maxim. and their Whitening Activities

The half-dried leaves of Stewartia. pseudocamellia were extracted with hot water (SPE) and partitioned with n-hexane (SPEH), dichloromethane (SPED), and ethyl acetate (SPEE) successively. SPE and SPEE showed significant inhibitory effects against melanogenesis and tyrosinase activities. By bioassay-guided isolation, ten phenolic compounds were isolated by column chromatography from SPEE. The whitening effect of the isolated compounds from SPEE were tested for the inhibitory activities against melanogenesis using B16 melanoma cells, in vitro inhibition of tyrosinase, and L-3,4-dihydorxy-indole-2-carboxylic acid (L-DOPA) auto-oxidation assay. A cytotoxic activity assay was done to examine the cellular toxicity in Raw 264.7 macrophage cells. Of the compounds isolated, gallic acid and quercetin revealed significant inhibitory activities against melanogenesis compared to arbutin. In particular, quercetin exhibited similar inhibitory activities against tyrosinase and L-DOPA oxidation without cytotoxicity. These results suggested that SPE could be used as a potential source of natural skin-whitening material in cosmetics as well as in food products.

Anti-Inflammatory, Antioxidant, Anti-Angiogenic and Skin Whitening Activities of Phryma leptostachya var. asiatica Hara Extract

This work aimed to assess some pharmacological activities of P. leptostachya var. asiatica Hara. The dried roots of P. leptostachya var. asiatica Hara were extracted with 70% ethanol to generate the powdered extract, named PLE. Anti-angiogenic activity was detected using chick chorioallantoic membrane (CAM) assay. In vitro anti-inflammatory activity was evaluated via analyzing nitric oxide (NO) content, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. Antioxidant activity was determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and reactive oxygen species (ROS) level in the stimulated macrophage cells. Matrix metalloproteinase-9 (MMP-9) and -2 (MMP-2) activities in the culture media were detected using zymography. PLE exhibits an anti-angiogenic activity in the CAM assay, and displays an inhibitory action on the generation of NO in the LPS-stimulated macrophage cells. In the stimulated macrophage cells, it is able to diminish the enhanced ROS level. It can potently scavenge the stable DPPH free radical. It suppresses the induction of iNOS and COX-2 and the enhanced MMP-9 activity in the stimulated macrophage cells. Both monooxygenase and oxidase activities of tyrosinase were strongly inhibited by PLE. Taken together, the dried roots of P. leptostachya var. asiatica Hara possess anti-angiogenic, anti-inflammatory, antioxidant and skin whitening activities, which might partly provide its therapeutic efficacy in traditional medicine.