The regulatory role of the tetrapeptide AcSDKP in skin and hair physiology and the prevention of ageing effects in these tissues – a potential cosmetic role

The naturally occurring tetrapeptide acetyl‐N‐Ser‐Asp‐Lys‐Pro (AcSDKP) recognized as a potent angiogenic factor was shown recently to contribute to the repair of cutaneous injuries. In the current article, we report the ability of AcSDKP to exert a beneficial effect on normal healthy skin and scalp and to compensate for the ageing process. In vitro AcSDKP at 10^?11–10^?7 M significantly stimulates the growth of human keratinocytes, fibroblasts and follicle dermal papilla cells. Moreover, it enhances the growth of human epidermal keratinocyte progenitor and stem cells as shown in a clonogenic survival assay. Topical treatment of ex vivo cultured skin explants with 10^?5 M AcSDKP increases the thickness of the epidermis and upregulates the synthesis of keratins 14 and 19, fibronectin, collagen III and IV as well as the glycoaminoglycans (GAGs). In the ex vivo‐cultured hair follicles, AcSDKP promotes hair shaft elongation and induces morphological and molecular modifications matching the criteria of hair growth. Furthermore, AcSDKP at 10^?11–10^?7 M was shown to improve epidermal barrier, stimulating expression of three protein components of tight junctions (claudin‐1, occludin, ZO‐1) playing an important role in connecting neighbouring cells. This tetrapeptide exercises also activation of SIRT1 implicated in the control of cell longevity. Indeed, a two‐fold increase in the synthesis of SIRT1 by cultured keratinocytes was observed in the presence of 10^?11–10^?7 M AcSDKP. In conclusion, these findings provide convincing evidence of the regulatory role of AcSDKP in skin and hair physiology and suggest a cosmetic use of this natural tetrapeptide to prevent skin ageing and hair loss and to promote the cutaneous regeneration and hair growth.     

Serum levels of IGF‐1 are related to human skin characteristics including the conspicuousness of facial pores

Conspicuous facial pores are one type of serious aesthetic defects for many women. However, the mechanism(s) that underlie the conspicuousness of facial pores remains unclear. We previously characterized the epidermal architecture around facial pores that correlates with the appearance of those pores in various ethnic groups including Japanese. The goal of this study was to evaluate the possible relationships between facial pore size, the severity of impairment of epidermal architecture around facial pores and sebum output levels to investigate the possible role of IGF‐1 in the pathogenesis of conspicuous facial pores. The subjects consisted of 38 healthy Japanese women (aged 22–41 years). IGF‐1 was measured using immunoradiometric assay. Surface replicas were collected to compare pore sizes of cheek skin and horizontal cross‐section images of cheek skin were obtained non‐invasively from the same subjects using in vivo confocal laser scanning microscopy and the severity of impairment of epidermal architecture around facial pores was determined. The skin surface lipids of each subject were collected from their cheeks and lipid classes were determined using gas chromatography/flame ionization detection. The serum level of IGF‐1 correlated significantly with total pore area (R = 0.36, P < 0.05), with the severity of impairment of epidermal architecture around facial pores (R = 0.43, P < 0.05) and with sebum output levels (R = 0.41, P < 0.01). The sebum output levels correlated with total pore area (R = 0.32, P < 0.05). Our study found that serum levels of IGF‐1 are correlated with facial skin characteristics including facial pore size and with the severity of impairment of epidermal architecture around facial pores.     

On the effects of a plant extract of Orthosiphon stamineus on sebum‐related skin imperfections

Overproduction of sebum is very common and results in an undesirable oily, shiny complexion with enlarged pores. Sebum secretion is basically under the control of 5‐α reductase, and more particularly under that of type 1 isozyme. But it is also highly sensitive to environmental factors such as temperature, humidity and food. Moreover, in Asia, the edicts of a flawless facial skin turn oily skin into a major concern for Asian women. We identified Orthosiphon stamineus leaf extract as an interesting ingredient for reducing the oily appearance of skin thanks to its ability to reduce 5‐α reductase type 1 expression in normal human epidermal keratinocytes in vitro. This was confirmed ex vivo, where Orthosiphon stamineus leaf extract was shown to reduce 5‐α reductase activity as well as the production of squalene, one of the main components of sebum that was used as a tracer of sebum. To evaluate the efficacy of Orthosiphon stamineus leaf extract at reducing sebum‐related skin imperfections in vivo, we performed two different clinical studies, one in France on a panel of Caucasian volunteers and the other one in Thailand on a panel of Asian volunteers. Using instrumental techniques as well as clinical evaluation and self‐evaluation, we could highlight that an O/W cosmetic formula containing 2% of Orthosiphon stamineus leaf extract could visibly reduce the oily appearance of skin as well as the size of pores, thus leading to a significant improvement of complexion evenness and radiance. Overall, the results obtained were better than those observed with the same formula containing 1% of zinc gluconate, an ingredient frequently used in oily skin care products.     

Evaluation of the efficacy of a dill extract in vitro and in vivo

Lysyl oxidase–like (LOXL) is an extracellular enzyme that catalyses the cross‐linking between microfibrils and tropoelastin (TE), thereby ensuring elastic fibre functionality. With ageing, LOXL expression decreases, thus participating in the loss of skin elasticity. In a previous study, we showed that a dill seed extract [INCI name: Peucedanum graveolens (Dill) extract] could increase LOXL expression in cultured dermal fibroblasts. Besides, we showed a good correlation between the measurements of skin elasticity obtained in vitro and in vivo using a fully automated bio‐tribometer designed to measure the biomechanical properties of soft and complex materials like skin. The aim of this study was to evaluate the ability of the dill extract to improve skin elasticity in vitro and in vivo using different models. Using the bio‐tribometer, we first showed that the lateral elasticity of dermis equivalents (DEs) treated with the dill extract at 1% was significantly increased by +29% (P < 0.01) when compared to untreated DEs. In vivo, skin firmness and elastic recovery measured using cutometry methods were also significantly improved compared to placebo in volunteers treated for 56 days with a formula containing 1% of dill extract. Moreover, the clinical evaluation evidenced significant improvements in ‘skin elasticity’ compared to placebo. A majority of subjects treated with the dill extract also noted significant improvements in skin elasticity, firmness and slackness of the jaw line. Finally, mean wrinkle area and length were also significantly reduced compared to placebo after 84 days as measured using silicone replicas taken from the crow’s feet. In summary, this study showed that the dill extract could improve elasticity of DEs in vitro as well as skin biomechanical properties and appearance in vivo. It also highlights the relevance of using the bio‐tribometer as an exploratory tool for the measurement of skin elasticity in vitro.     

Presented at the 16th DGK Symposium, March 2–4, 2005, Leipzig, Germany – Received the Award for the Best Poster Presentation 1Influencing the equilibrium of the cutaneous ecosystem to improve the properties of skin prone to acne

The skin is colonized by a variety of microorganisms such as Propionibacterium acnes, Staphylococcus epidermidis and Malassezia furfur that are in a stable balance and form the resident skin flora. The homeostasis of this ecosystem is of fundamental importance as it plays a barrier role by limiting the invasion and growth of pathogenic bacteria on the skin surface. An internal or external change in the skin environment, a transitory lack of hygiene, a change in hormone status or hyperseborrhea can upset this balance at any time and enable the proliferation of saprophytic skin microorganisms or contamination by pathogens. Hyperseborrhea causes retention lesions such as open comedos and closed microcysts that can be transformed into papulae, pustules or nodules in the case of an inflammatory reaction caused by abnormal bacterial proliferation. These skin disorders are particularly pronounced between the ages of 12 and 25 but nonetheless affect all ages and cause oily skin accompanied by unsightly imperfections that are difficult to camouflage and live with. The skin combats microbial infections with its natural defense system. Keratinocytes produce and secrete a large number of peptides with direct and indirect antimicrobial activity (cathelicidins, β‐defensins). These natural antimicrobial peptides limit the proliferation of pathogenic bacteria and fungi such as Staphylococcus aureus or Candida albicans and can also induce an indirect immune response. They are indispensable for the homeostasis of the cutaneous ecosystem and are over‐expressed by keratinocytes in response to an inflammatory stimulus or an infection. When these natural defenses are disturbed or overwhelmed, they must be stimulated to limit the inflammatory reactions that result in the appearance of skin imperfections such as acne. To this end, we have developed an extract purified from Filipendula ulmaria (meadowsweet) that is rich in phenolic acids. Tested at 1% on human keratinocytes, the F. ulmaria extract stimulated the natural defense functions of the skin by boosting the synthesis of cathelicidins by 130%. In addition, when tested in vivo at 4%, the F. ulmaria extract significantly reduced the lipid index by 12% in 71% of volunteers after 28 days of twice‐daily treatment. The F. ulmaria extract stimulates the natural defense functions of the skin, preventing the proliferation of bacteria on the skin surface and thereby limiting complications from acne: The number of spots and their total occupied surface were significantly reduced by ‐10% and ‐12%, respectively. Finally, dermatological evaluation after 28 days of twice‐daily use showed the capacity of the F. ulmaria extract to significantly improve the quality of skin prone to acne: The homogeneity of skin grain was improved (+21%), the number of inflammatory lesions reduced (‐20%) and the infiltration of lesions decreased (‐22%).     

Skin benefits of a myconoside-rich extract from resurrection plant Haberlea rhodopensis

Resurrection plant Haberlea rhodopensis develops molecules to survive drought stress. These molecules allow the plant to resurge from a desiccation state. We have extracted a specific fraction from the plant (Haberlea extract) and found it rich, among other molecules, of a caffeoyl phenylethanoid glycoside called myconoside, a molecule extremely abundant in the plant with a potential role in survival. Peroxide‐stressed normal human dermal fibroblasts treated with the Haberlea extract, showed increased collagen VI (+822%), collagen XVI (+928%) and elastin (+144%) mRNA synthesis, measured by RT‐qPCR. This effect was superior to those obtained with benchmarks retinoic acid and retinol. When used at 3% in human skin biopsies, Haberlea extract protected against UV‐induced dermis oxidation by 100% (P < 0.01), as evidenced by immunohistochemistry. Finally, when tested in human volunteers (n = 20) at 3% in a cream against a placebo, Haberlea extract increased skin elasticity (3× placebo, P < 0.0002) and skin radiance (4× placebo, P < 0.05) after only 15 days of treatment, with the effect sustained after 30 and 60 days of treatment. We demonstrated that by using Haberlea extract (particularly rich in glycoside myconoside), it is possible to strongly stimulate antioxidant skin defences and extracellular matrix protein synthesis. This effect, in turn, will further stimulate skin elasticity and skin radiance significantly in human volunteers. The extract can be suggested for anti‐ageing treatments, intended for claims such as protection from oxidation, increased skin elasticity and enhanced skin radiance.     

Exposure to acute electromagnetic radiation of mobile phone exposure range alters transiently skin homeostasis of a model of pigmented reconstructed epidermis

Exposure to electromagnetic radiations (EMR) produced by mobile phone concerns half the world's population and raises the problem of their impact on human health. In this study, we looked at the effects of mobile phone exposure (GSM basic, 900 MHz, SAR 2 mW g^?1, 6 h) on a model of pigmented skin. We have analysed the expression and localization of various markers of keratinocyte and melanocyte differentiation 2, 6, 18 and 24 h after EMR exposure of reconstructed epidermis containing either only keratinocytes or a combination of keratinocytes and melanocytes grown on dead de‐epidermized dermis, using histology, immunohistochemistry and Western blot. No changes were found in epidermal architecture, localization of epidermal markers, presence of apoptotic cells and the induction of p53 in both types of epidermis (with or without melanocytes) after exposure to EMR. In pigmented reconstructs, no change in the location and dendricity of melanocytes and in melanin transfer to neighbouring keratinocytes was detected after EMR exposure. Loricrin, cytokeratin 14 were significantly decreased at 6 h. The level of all markers increased at 24 h as compared to 6 h post‐EMR exposure, associated with a significant decrease of the 20S proteasome activity. Our data indicate that exposure to 900 MHz frequency induces a transient alteration of epidermal homoeostasis, which may alter the protective capacity of the skin against external factors. Presence or absence of melanocytes did not modify the behaviour of reconstructs after EMR exposure.     

Singlet molecular oxygen quenching by the antioxidant dimethylmethoxy chromanol in solution and in ex vivo porcine skin

Singlet‐oxygen is a non‐radical reactive oxygen species believed to play a major role in many photooxidation processes in connection with diverse photo‐biological processes such as skin ageing or photocarcinogenesis. Dimethylmethoxy chromanol (3,4‐dihydro‐6‐hydroxy‐2,2‐dimethyl‐7‐methoxy‐1(2H)‐benzopyran) is a potent antioxidant used in cosmetic and pharmaceutical formulations. We have assessed the singlet oxygen quenching ability of dimethylmethoxy chromanol, by monitoring the near‐IR phosphorescence of singlet‐oxygen in solution and in ex vivo porcine skin samples. Dimethylmethoxy chromanol quenches singlet oxygen with a rate constant of (1.3 ± 0.1) × 10⁸ M^?1 s^?1 in solution. Consistent with this, a clear reduction in the singlet oxygen lifetime and emission intensity was observed when ex vivo porcine skin samples were treated with dimethylmethoxy chromanol.     

Schinus terebinthifolius Raddi extract and linoleic acid from Passiflora edulis synergistically decrease melanin synthesis in B16 cells and reconstituted epidermis

Several treatments for skin whitening are available today, but few of them are completely adequate, especially owing to the carcinogenic potential attributed to classical drugs like hydroquinone, arbutin and kojic acid. To provide an alternative and safer technology for whitening, we developed two botanical compounds originated from Brazilian biodiversity, an extract of Schinus terebinthifolius Raddi and a linoleic acid fraction isolated from Passiflora edulis oil. The whitening effect of these compounds was assessed using biochemical assays and in vitro models including cellular assays and equivalent skin. The results showed that S. terebinthifolius Raddi extract is able to reduce the tyrosinase activity in vitro, and the combination of this extract with linoleic acid is able to decrease the level of melanin produced by B16 cells cultured with melanocyte‐stimulating hormone. Furthermore, melanin was also reduced in human reconstituted epidermis (containing melanocytes) treated with the compounds. The combination of the compounds may provide a synergistic positive whitening effect rather than their isolated use. Finally, we demonstrated that the performance of these mixed compounds is comparable to classical molecules used for skin whitening, as kojic acid. This new natural mixture could be considered an alternative therapeutic agent for treating hyperpigmentation and an effective component in whitening cosmetics.     

Screening of plant extracts for human tyrosinase inhibiting effects

Screening for tyrosinase (TYR) inhibitors potentially useful for control of skin pigmentation has been hampered by the limited availability of human TYR. To overcome this hurdle, we have established human embryonic kidney (HEK293)‐TYR cells that constitutively express human TYR. In the current study, we assayed human TYR inhibition activities of 50 plant extracts using the lysates of transformed HEK293‐TYR cells. The strongest inhibition of human TYR was shown by the extract of Vaccinium bracteatum Thunberg, followed by the extract of Morus bombycis Koidzumi. The former extract did not inhibit mushroom TYR activity whereas significant inhibition was observed with the latter extract, demonstrating the importance of using human TYR in the screening for human TYR inhibitors. Upon liquid‐liquid partitioning of the extract from V. bracteatum, the active constituents were enriched in the ethyl acetate fraction, and the subsequent preparatory thin‐layer chromatography identified p‐coumaric acid (PCA) as the main active constituent. The hypo‐pigmentation of PCA was verified in the MelanoDerm? Skin Model. This study demonstrates that transformed HEK293‐TYR cells could expedite the discovery of human TYR‐specific inhibitors from natural sources which might be useful in the control of skin pigmentation.     

Infant skin physiology and development during the first years of life: a review of recent findings based on in vivo studies

Infant skin is often presented as the cosmetic ideal for adults. However, compared to adult skin it seems to be more prone to develop certain pathological conditions, such as atopic dermatitis and irritant contact dermatitis. Therefore, understanding the physiology of healthy infant skin as a point of reference is of interest both from the cosmetic as well as from the clinical point of view. Clinical research on healthy infants is, however, limited because of ethical considerations of using invasive methods and therefore until recently data has been scarce. Technical innovations and the availability of non‐invasive in vivo techniques, such as evaporimetry, electrical impedance measurement, in vivo video and confocal microscopy, and in vivo fibre‐optic based spectroscopy, opened up the field of in vivo infant skin physiology research. Studies incorporating such methods have demonstrated that compared to adult, infant skin continues to develop during the first years of life. Specifically, infant skin appears to have thinner epidermis and stratum corneum (SC) as well as smaller corneocytes at least until the second year of life. The water‐handling properties are not fully developed before the end of the first year and infant SC contains more water and less amounts of natural moisturizing factors. Such findings re‐evaluate the old notions that skin is fully matured at birth. Armed with this knowledge, we are in a position not only to better understand infant dermatological conditions but also to design better skin care products respecting the distinct qualities of infant skin.     

Lifting properties of the alkamide fraction from the fruit husks of Zanthoxylum bungeanum

The fruits of various Zanthoxylum species are used as a spice in the Chinese and Japanese cuisine because of their delicate flavour and tingling properties. The lipophilic hydroxyalkamides hydroxy α‐ and β‐sanshools ( 1a,b ) have been identified as the tingling principles of these plants, and previous studies have validated a sanshool‐rich lipophilic extract from the fruit husks of Z. bungeanum Maxim. (Zanthalene^®) as an anti‐itching cosmetic ingredient. Because tingling is a sort of ‘paralytic pungency’, and Zanthalene^® potently inhibits synaptic transmission, we have investigated its capacity to relax subcutaneous muscles and act as a topical lifting agent for wrinkles. An anti‐wrinkles extract rich in spilanthol ( 2 ), a lipophilic alkamide having sensory properties similar to those of Zanthalene^®, was used as a reference. Short‐term (lifting effect) and long‐term (anti‐wrinkle) improvements of skin roughness parameters were evaluated by both objectives’ and subjectives’ measurements. An immediate ‘lifting’ effect was observed with the sanshool‐rich lipophilic extract, at dosages at which the reference alkamide extract was inactive in the objective assays. Limited desensitization after repeated application and good overall tolerability were observed, although a modest long‐term anti‐wrinkle effect was shown by both products. Taken together, these observations validate the use of sanshool‐rich lipophilic extracts as an efficacious, immediate‐action lifting agent, and exemplify the relevance of sensory observations to foster the development of innovative cosmetic ingredients.     

Clinical evaluation of a dioic acid‐based formulation on facial skin in an Indian population

The aim of this work was to investigate the effects of 1,18‐octadecen‐9‐dioic acid (dioic acid) and a Rumex occidentalis extract complex for their skin‐lightening action in an Indian population. Prior to the clinical study, the efficacy of dioic as an inhibitor of melanogenesis was confirmed on dark‐pigmented human melanocytes. As part of a 12‐week vehicle‐controlled clinical study, the skin‐lightening effect of a test product containing 1% dioic acid, 2% of a Rumex occidentalis extract and sunscreens (SPF 15) was assessed on the facial skin of 71 Indian female volunteers. Change in skin colour was monitored by (A) Chroma Meter^® measurement (L*, a*, b*) and Individual Typology Angle (ITA?) calculation and (B) Visual grading of standardized photographs by a dermatologist. Colorimetric measurements on volunteers' cheeks showed a significant increase of L* and ITA? compared to baseline after 4, 8 and 12 weeks of test product application. For both L* and ITA? measurements, changes were significantly different than the SPF 15‐containing vehicle at weeks 4 and 12. These results were confirmed by the dermatological visual grading. The overall skin‐lightening action of the test product was beyond the one observed with the SPF 15 vehicle. These findings show that a dioic acid and Rumex occidentalis complex deliver a significant skin‐lightening effect on facial skin in an Indian population.     

In vitro evaluation of the efficacy of commercial green tea extracts in UV protection

Plants with antioxidant properties are beneficial for preventing the ageing events evoked by UV light, and numerous products based on Camellila sinensis (green tea) are commercially available, many of which claiming to contain bioactive compounds that would prevent UV‐induced skin damage. In this study, we tested the efficacy of five commercial green tea extracts used to enrich cosmetic formulations for protecting human and mouse fibroblasts against UV radiation effects and compared with a fluid one prepared according to the Brazilian Pharmacopoeia recommendations. Taking into consideration that the ageing process can be accelerated by solar radiation by excessive free radical generation, leading to depletion of skin antioxidant defences, and its collapse caused by disruption of the metalloproteinase metabolism, we have used their individual (‐)‐epigallocathechin‐3‐gallate (EGCG) content, the catalase and SOD status and the matrix‐degrading metalloproteases (MMP)‐1, MMP‐9 and MMP‐13 levels as comparative parameters. The EGCG content of the commercial products showed wide variability, ranging from undetectable levels to 58.65 ± 1.12 μg mL^?1, in contrast with the fluid extract (87.82 ± 1.35 μg mL^?1). Moreover, only the pharmacopoeic extract was able to significantly reduce MMP degradation while enhancing the levels of SOD and catalase. These results indicate, for the first time, that the methodologies for preparing herbal mixtures can interfere significantly with compounds endowed with photoprotective effects, and the efficacy of products containing C. sinensis extracts thought to act against effects of solar radiation can be compromised.     

In vitro and in vivo assessment of the effect of Laurus novocanariensis oil and essential oil in human skin

Laurus novocanariensis is an endemic plant from the Madeira Island forest that derives a fatty oil, with a strong spicy odour, from its berries that has been used for centuries in traditional medicine to treat skin ailments. This work aimed to investigate the effect of the application of both the oil and its essential oil on normal skin, to assess their safety and potential benefits. Diffusion studies with Franz cells using human epidermal membranes were conducted. The steady‐state fluxes of two model molecules through untreated skin were compared with those obtained after a 2‐h pre‐treatment with either the oil or the essential oil. Additionally, eleven volunteers participated in the in vivo study that was conducted on the forearm and involved daily application of the oil for 5 days. Measurements were performed every day in the treated site with bioengineering methods that measure erythema, irritation and loss of barrier function. Slightly higher steady‐state fluxes were observed for both the lipophilic and the hydrophilic molecule when the epidermal membranes were pre‐treated. Nevertheless, such differences had no statistical significance, which seems to confirm that neither the oil nor the essential oil impaired the epidermal barrier. Results collected with the Chromameter, the Laser Doppler Flowmeter and the visual scoring are in agreement with those established in the in vitro study. They indicate that the repeated application of the oil did not cause erythema, because the results observed in the first day of the study were maintained throughout the week. Application of the oil did not affect the skin barrier function, because the transepidermal water loss remained constant throughout the study. The stratum corneum hydration was slightly reduced on days 4 and 5. This work shows that both the oil and the essential oil were well tolerated by the skin and did not cause significant barrier impairment or irritation.     

Chemical analysis and photoprotective effect of an extract of wine from Jacquez grapes

The present study was aimed at evaluating the in vitro antioxidant activity and in vivo photoprotective activity of an extract of wine obtained from Jacquez (Vitis aestivalis‐cinerea × V vinifera) grapes (JW‐E). The chemical profile of the JW‐E was characterised by a significant level of proanthocyanidins, together with lower amounts of anthocyanins and hydroxycinnamic acids. The antioxidant activity of the JW‐E was assessed by means of various in vitro tests (bleaching of the stable 1,1‐diphenyl‐2‐picrylhydrazyl radical; peroxidation, induced by the water‐soluble radical initiator 2,2′‐azobis(2‐amidinopropane) hydrochloride, on mixed dipalmitoylphosphatidylcholine/linoleic acid unilamellar vesicles; UV radiation‐induced peroxidation in phosphatidylcholine multilamellar vesicles). In all in vitro tests employed, the JW‐E proved to possess strong antioxidant/free radical‐scavenging effectiveness. Furthermore, when topically applied, a gel formulation containing the JW‐E afforded significant in vivo protection against UVB light‐induced skin erythema (monitored by reflectance spectrophotometry) in healthy human volunteers. © 2002 Society of Chemical Industry     

Potential of Glycosidase from Non‐Saccharomyces Isolates for Enhancement of Wine Aroma

The aim of this work was to rapidly screen indigenous yeasts with high levels of β‐glucosidase activity and assess the potential of glycosidase extracts for aroma enhancement in winemaking. A semiquantitative colorimetric assay was applied using 96‐well plates to screen yeasts from 3 different regions of China. Isolates with high β‐glucosidase activity were confirmed by the commonly used pNP assay. Among 493 non‐Saccharomyces isolates belonging to 8 generas, 3 isolates were selected for their high levels of β‐glucosidase activity and were identified as Hanseniaspora uvarum, Pichia membranifaciens, and Rhodotorula mucilaginosa by sequence analysis of the 26S rDNA D1/D2 domain. β‐Glucosidase in the glycosidase extract from H. uvarum strain showed the highest activity in winemaking conditions among the selected isolates. For aroma enhancement in winemaking, the glycosidase extract from H. uvarum strain exhibited catalytic specificity for aromatic glycosides of C₁₃‐norisoprenoids and some terpenes, enhancing fresh floral, sweet, berry, and nutty aroma characteristics in wine.     

Structural characterisation and immunomodulatory effects of polysaccharides isolated from Dendrobium aphyllum

A crude polysaccharide extract of Dendrobium aphyllum (cDAP, yield 38.15 ± 0.20%) was generated. The D. aphyllum polysaccharide (DAP, M_w 471.586 kDa), purified by DEAE‐Sepharose and Sephadex‐G200 Fast Flow, was composed of mannose (71.3%) and glucose (28.7%), according to GC–MS analysis. Its backbone was composed of β‐d ‐mannopyranose and β‐d ‐glucopyranose residues, as revealed by infrared spectroscopic analysis. Its glycosidic bond was mainly 1, 4‐linked, and the O‐acetyl groups were mainly linked to mannose residues, according to periodate oxidation and Smith degradation analysis. The DAP units polymerised into a filiform‐shaped spatial pattern, as characterised by atomic force microscopy and scanning electron microscopy. DAP treatment enhanced cytokine secretion (nitric oxide, interleukin‐6 and tumour necrosis factor‐α) and pinocytic and phagocytic capacities of RAW 264.7 mouse macrophages. The complement receptor 3 and mannose receptor were identified to be the receptors of DAP on RAW 264.7 cells, indicating that the Akt/mTOR/MAPK and IKK/nuclear factor‐?B pathways could be involved in DAP‐activated immunomodulation.     

Preparation of Methylated Products of A‐type Procyanidin Trimers in Cinnamon Bark and Their Protective Effects on Pancreatic β‐Cell

Polyphenols are partial metabolized to methylated conjugations in vivo, and then could modify bioavailability and bioactivity related to the uptake of parent compounds. Our previous studies have found that the antidiabetic effects of cinnamon barks are mainly related to polyphenol components, particularly A‐type procyanidin trimer cinnamtannin‐1 (CT1). It is necessary to understand the antidiabetic activity of methylations of CT1, nevertheless, sufficient amounts of methylated CT1 are difficult to obtain from metabolites in vivo. In this study, O‐methyl derivatives of CT1 were prepared through one‐pot methyl iodide reaction and isolation via column chromatography and RP‐HPLC semipreparation. The structures of O‐methyl substituents were determined through NMR (Nuclear Magnetic Resonance) and HPLC‐ESI‐MS (High‐performance liquid chromatography‐electrospray ionization‐mass spectrometry). Five purified O‐methyl substituents and 2 isomers of CT1 were obtained. Their protective effects on a palmitic acid‐induced pancreatic β‐cell apoptosis model were then evaluated. Results showed that the protective effects on pancreatic β‐cell of O‐methyl substituents were weaker than those of CT1. The results suggested that the methylation of catechol groups could be a relevant factor contributing to the decline of protective effects on pancreatic β‐cell of CT1 via obstructing quinone intermediate formation and affecting antioxidant abilities. The antidiabetic effects of O‐methyl derivatives of CT1 should be further determined by other antidiabetic models.     

Anti-obesity role of adzuki bean extract containing polyphenols: in vivo and in vitro effects

BACKGROUND: The aim of this work was to evaluate the effects of polyphenol‐rich adzuki bean extract on lipid metabolism, triglyceride accumulation and proinflammatory cytokine secretion in vivo and in vitro. RESULTS: For the in vivo study, rats were divided into four groups: group C was fed a control diet, group A was fed the control diet with 1% adzuki bean extract, group CF was fed a high fat diet, and group AF was fed a high fat diet with 1% adzuki bean extract. For the in vitro study, the ability of adzuki bean extract to suppress triglyceride incorporation, glycerol phosphate dehydrogenase activity and inflammatory response was investigated in cultured human adipocytes. Data from the animal study showed that adzuki bean extract improved lipid metabolism in both the normal and high‐fat diet groups. Adzuki bean extract treatment in the high‐fat group resulted in significant reductions in total hepatic lipid accumulation and lipid secretion into the feces. Incubation of adipocytes with adzuki bean extract significantly decreased triglyceride accumulation, glycerol phosphate dehydrogenase activity and inflammatory responses without affecting cell viability. CONCLUSION: The results of this study demonstrate that adzuki bean extract has high potential to serve as a natural anti‐obesity agent. Copyright © 2012 Society of Chemical Industry