Identification of Antioxidant Metabolites from Five Plants (Calophyllum inophyllum, Gardenia taitensis, Curcuma longa, Cordia subcordata, Ficus prolixa) of the Polynesian Pharmacopoeia and Cosmetopoeia for Skin Care.

Oxidative stress contributes to impairment of skin health, the wound healing process, and pathologies such as psoriasis or skin cancer. Five Polynesian medicinal plants, among the most traditionally used for skin care (pimples, wounds, burns, dermatoses) are studied herein for their antioxidant properties: Calophyllum inophyllum, Gardenia taitensis, Curcuma longa, Cordia subcordata, and Ficus prolixa. Plant extracts were submitted to in vitro bioassays related to antioxidant properties and their bioactive constituents were identified by a metabolomic analytical approach. High performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS) analysis was performed leading to the characterization of 61 metabolites. Compounds annotated for F. prolixa and C. subcordata extracts were reported for the first time. Antioxidant properties were evaluated by total phenolic content (TPC), free radical scavenging DPPH (1,1-diphenyl-2-picryl-hydrazyl), and Ferric Reducing Antioxidant Power activity (FRAP) assays. F. prolixa extract was the most active one and showed antioxidant intracellular activity on keratinocytes by Anti Oxydant Power 1 assay. Online HPLC-DPPH allowed the identification of phenolic bioactive compounds such as quercetin-O-rhamnoside, rosmarinic acid, chlorogenic acid, procyanidins, epicatechin, 5-O-caffeoylshikimic acid, and curcumin as being responsible for the scavenging properties of these plant extracts. These results highlight the potential of F. prolixa aerial roots as a source of antioxidants for skin care applications.

Traditional medical practices for children in five islands from the Society archipelago (French Polynesia).

BACKGROUND: Traditional Polynesian medicine for children has been poorly documented, and few data are available on their efficacy and safety. In this context, the aim of this study was to identify traditional practices used for treating children and then assess the efficacy and safety of the most cited remedies by reviewing the literature. METHODS: In 2022, a semi-structured survey was carried out on five islands from the Society archipelago (Bora Bora, Huahine, Moorea, Raiatea, and Tahiti). A total of 86 participants were interviewed including 19 experts in herbalism. A thorough literature review was performed on the most cited plant species to gather the relevant ethnobotanical, pharmacological, and clinical data of each remedy. RESULTS: Participants mentioned using 469 remedies to treat 69 health disorders. The most represented health categories were digestive system, skin disorders, infectious diseases, and respiratory system. A total of 67 plant species (representing 731 use-reports) were mentioned and Annona muricata, Gardenia taitensis, and Hibiscus rosa-sinensis were the main plants reported. Regarding the safety of cited remedies, one plant (Microsorum grossum) showed high risk of toxicity, and its use should be avoided in infants and children. CONCLUSION: Our survey confirms the importance of traditional medical practices for children in the Society Islands. A lack of data in children for most cited remedies demonstrate the need for more pharmacological and toxicological research on Polynesian medicinal plants. Finally, the potential risk of toxicity for some cited plant species reported calls for a better information of traditional medicine users and healers.

Antimicrobial Properties of Compounds Isolated from Syzygium malaccense (L.) Merr. and L.M. Perry and Medicinal Plants Used in French Polynesia.

A preliminary ethnopharmacological survey, achieved in French Polynesia, led to the collection of the most cited plants among 63 species used to treat "infectious" diseases, with a description of their medicinal uses. Bibliographical investigations and antimicrobial screening permitted the selection of the botanical species Syzygium malaccense (Myrtaceae) for phytochemical analysis. Leaves of Syzygium malaccense were usually used in mixture with rhizomes of Curcuma longa to treat infectious diseases such as cystitis. The methanolic plant extracts were tested in vitro with an agar microdilution method on 33 bacteria strains and 1 yeast to obtain their Minimal Inhibitory Concentration (MIC), and cytotoxicity against HepG2 cells were evaluated. Antimicrobial synergistic effects of methanolic plant extracts from leaves of Syzygium malaccense and rhizomes from Curcuma longa were also evaluated. The bio-guided isolation of leaf extract from Syzygium malaccense led to the identification of seven alkyl-salicylic acids (anacardic acids or ginkgolic acids C15:0, C15:1, C17:0, C17:1, C17:2, C17:3 and C19:1) described for the first time in this species. All compounds were tested against Staphylococcus aureus (18.75 < MIC < 75.0 µg/mL), Streptococcus pyogenes (2.34 < MIC < 18.75 µg/mL) and Pseudomonas aeruginosa (MIC = 150 µg/mL), and their structure−activity relationships were discussed. The methanolic extract and salicylic derivatives from S. malaccense showed an interesting antimicrobial activity against Gram+ bacteria, without toxicity on hepG2 cells at 400 µg/mL. Moreover, these antibacterial compounds have already been studied for their anti-inflammatory activity, which supports the therapeutic interest of S. malaccense against infectious diseases.

Polynesian medicine used to treat diarrhea and ciguatera: An ethnobotanical survey in six islands from French Polynesia.

ETHNOPHARMACOLOGICAL RELEVANCE: In French Polynesia, many pathologies common or endemic to the territory cause diarrhea. This is the case for rotavirus gastroenteritis, salmonella food poisoning, ingestion of water contaminated by bacteria, and ciguatera. To treat these ailments, the population may employ traditional medicine for cultural reasons, geographical isolation, and poor health coverage. Polynesian remedies are often used without medical consultation and there is no data on their benefit-risk balance. A few ethnobotanical studies have been carried out in order to identify the traditional remedies used for various ailments, but few studies have focused on gastrointestinal pathologies. In this context, an ethnobotanical survey was carried out to identify treatments used for diarrhea and ciguatera, inventory the plants used, better understand the local representation of these remedies, and provide efficacy and safety data on these uses. MATERIALS AND METHODS: From February to April 2021, a semi-structured survey was conducted on six islands in French Polynesia, including one island in the Windward Islands archipelago (Tahiti), three islands in the Marquesas archipelago (Hiva Oa, Nuku Hiva, Tahuata), and two islands in the Leeward Islands archipelago (Raiatea, Tahaa). A total of 133 people was interviewed including 34 specialists (of which 29 experts in herbalism). RESULTS: These people mentioned the use of 27 plants for the treatment of diarrhea, and 24 for the treatment of ciguatera. Citrus aurantiifolia, Psidium guajava and Cordyline fruticosa were the three most cited plant species used for treating diarrhea, while Cocos nucifera, Punica granatum and Barringtonia asiatica were the most cited for ciguatera. A large majority of plants are widespread and introduced plants, which is congruent with the history of Polynesian people. While some plants are well known for similar uses (e.g. Psidium guajava for diarrhea, Heliotropium arboreum for ciguatera), others are less well known and may present toxicity risks (e.g. Barringtonia asiatica for ciguatera). CONCLUSION: Traditional Polynesian medicine is an integral part of the local culture so important to be preserved and valued. However, more pharmacological and toxicological studies are still needed to determine the benefit-risk balance of some of these remedies and to allow their official integration into the Polynesian health system.

Improving the Antioxidant Properties of Calophyllum inophyllum Seed Oil from French Polynesia: Development and Biological Applications of Resinous Ethanol-Soluble Extracts.

Tamanu oil from Calophyllum inophyllum L. has long been used in traditional medicine. Ethanol extraction was found the best strategy for recovering bioactive compounds from the resin part of Tamanu oil, yielding two neutral and acidic resins fractions with high phenolics, flavonoids and pyranocoumarins concentrations. A further cascade of LPLC/HPLC separations of neutral and acidic resin fractions allowed identifying fifteen metabolites, and among them, calanolide D and 12-oxocalanolide A (both in neutral fraction) were first identified from a natural source. All these extracts, subfractions and isolated metabolites demonstrated increased free radical scavenging, antioxidant, anti-inflammatory, antimicrobial and antimycobacterial activity compared to Tamanu oil and its de-resinated lipid phase. Overall, these results could promote resinous ethanol-soluble Tamanu oil extracts as a useful multifaceted and renewable medicinal resource.

Feature-Based Molecular Networks Identification of Bioactive Metabolites from Three Plants of the Polynesian Cosmetopoeia Targeting the Dermal Papilla Cells of the Hair Cycle.

The term cosmetopoeia refers to the use of plants in folks' cosmetics. The aerial parts of Bidens pilosa L., the leaves of Calophyllum inophyllum L. and the fruits of Fagraea berteroana A.Gray ex Benth are traditionally used in French Polynesia for hair and skin care. During the hair cycle, dermal papilla cells and their interaction with epithelial cells are essential to promote hair follicle elongation. The aim of our investigations was the identification of metabolites from these three plants and chemical families responsible for their hair growth activity. A bioactivity-based molecular network was produced by mapping the correlation between features obtained from LC-MS/MS data and dermal papilla cell proliferation, using the Pearson correlation coefficient. The analyses pointed out glycosylated flavonols and phenolic acids from B. pilosa and C. inophyllum, along with C-flavonoids, iridoids and secoiridoids from F. berteroana, as potential bioactive molecules involved in the proliferation of hair follicle dermal papilla cells. Our results highlight the metabolites of the plant species potentially involved in the induction of hair follicle growth and support the traditional uses of these plants in hair care.

Chemotaxonomy and cytotoxicity of the liverwort Porella Viridissima.

The first chemotaxonomic study based on volatile components of Porella viridissima (Mitt.) Grolle is reported. The GC-MS analysis of ether extract was performed; ten santalane and five pinguisane-type sesquiterpenes were identified together with perrottetianal A as major diterpene. Most of detected santalane-type sesquiterpenes are reported for the first time in liverwort. P. viridissima was found to belong to the chemotype III (pinguisane/sacculatane) and shared chemical similarities with P. navicularis. Perrotettianal A was isolated and has shown strong cytotoxicity against ovarian cancer.

Hair Growth Activity of Three Plants of the Polynesian Cosmetopoeia and Their Regulatory Effect on Dermal Papilla Cells.

Hair loss is becoming increasingly prevalent as dietary and living habits change. The search for natural products to limit hair loss has led to tapping into traditional cosmetic knowledge. We studied three plants of the Polynesian cosmetopoeia, Bidens pilosa, Calophyllum inophyllum and Fagraea berteroana, to determine their ability to promote hair growth. Their chemical content was characterized by liquid chromatography coupled to mass spectrometry (LC-MS). Their proliferative activity on dermal papilla cells (DPCs) was assessed via MTT assay and molecular targets were evaluated by RT-qPCR analysis of seven factors involved in the modulation of the hair cycle, CCND1, LEF1, DKK1, WNT5A PPARD, TGFΒ1, PPARD and RSPO2. Our results show that our extracts significantly increased proliferation of dermal papilla cells. Furthermore, LC-MS/MS analysis revealed a diversity of molecules, flavonoids, iridoids and organic acids, some known for hair-inducing properties. Finally, specific extracts and fractions of all three plants either upregulated CCND1, LEF1 and PPARD involved in stimulating hair follicle proliferation and/or lowered the gene expression levels of hair growth inhibiting factors, DKK1 and TGFB1. Our findings suggest that extracts from B. pilosa, C. inophyllum and F. berteroana are interesting candidates to stimulate hair growth.

Dimeric and esterified sesquiterpenes from the liverwort Chiastocaulon caledonicum.

This is the first chemical investigation of Chiastocaulon caledonicum, an endemic liverwort from New Caledonia. We herein present the isolation of thirteen compounds including seven undescribed sesquiterpenoids, namely four barbatane- and three myltaylane-type sesquiterpenes. The structures of these compounds were elucidated based on the interpretation of their chemical and spectroscopic/spectrometric data. Chiastocaulins A and B are the first examples of dimers based on two myltaylane units. The chemotaxonomic importance and the biosynthesis of the chiastocaulin structure are discussed. Terpenoid dimers formed via a Diels-Alder cyclization are thought to be specific to the Plagiochilaceae family.

Dimethylsulfoniopropionate concentration in coral reef invertebrates varies according to species assemblages.

Dimethylsulfoniopropionate (DMSP) is a key compound in the marine sulfur cycle, and is produced in large quantities in coral reefs. In addition to Symbiodiniaceae, corals and associated bacteria have recently been shown to play a role in DMSP metabolism. Numerous ecological studies have focused on DMSP concentrations in corals, which led to the hypothesis that increases in DMSP levels might be a general response to stress. Here we used multiple species assemblages of three common Indo-Pacific holobionts, the scleractinian corals Pocillopora damicornis and Acropora cytherea, and the giant clam Tridacna maxima and examined the DMSP concentrations associated with each species within different assemblages and thermal conditions. Results showed that the concentration of DMSP in A. cytherea and T. maxima is modulated according to the complexity of species assemblages. To determine the potential importance of symbiotic dinoflagellates in DMSP production, we then explored the relative abundance of Symbiodiniaceae clades in relation to DMSP levels using metabarcoding, and found no significant correlation between these factors. Finally, this study also revealed the existence of homologs involved in DMSP production in giant clams, suggesting for the first time that, like corals, they may also contribute to DMSP production. Taken together, our results demonstrated that corals and giant clams play important roles in the sulfur cycle. Because DMSP production varies in response to specific species-environment interactions, this study offers new perspectives for future global sulfur cycling research.

Glucosinolates of the only three Brassicales indigenous to French Polynesia.

The glucosinolate (GL) profiles in leaf and stem of Rorippa sarmentosa (G.Forst. ex DC.) J.F.Macbr., Lepidium bidentatum Montin var. bidentatum, and Capparis spinosa subsp. cordifolia (Lam.) Fici indigenous to French Polynesia were investigated for the first time using LC-MS analysis. In the present study, we have established the presence of 8 known GLs in R. sarmentosa: 4-(methylsulfinyl)butyl- (1), but-3-enyl- (2), 5-(methylsulfinyl)pentyl- (3), 6-(methylsulfinyl)hexyl- (4), indol-3-ylmethyl- (6), 2-phenylethyl- (7), 8-(methylsulfinyl)octyl- (8), and 9-(methylsulfinyl)nonyl- (9) GLs. We have also tentatively identified for the first time the presence in R. sarmentosa of 7-(methylsulfinyl)heptyl GL (5). In addition, we have identified two known GLs in L. bidentatum var. bidentatum: benzyl- (10) and 4-methoxybenzyl- (11) GLs. Finally, the known methyl GL (12) was shown to be largely predominant in C. spinosa subsp. cordifolia.

A selection of eleven plants used as traditional Polynesian cosmetics and their development potential as anti-aging ingredients, hair growth promoters and whitening products.

ETHNOPHARMACOLOGICAL RELEVANCE: In French Polynesia, embellishment of the hair and skin is an important cultural and everyday practice. Yet, little research has focused on traditional preparations used for beautification in this region and their potential development as innovative cosmetic ingredients. AIM OF THE STUDY: In this present study we aim to assess and compile the ethnocosmetic potential of plants of French Polynesia to select and further study plants showing the most promise to be developed as anti-aging, anti-blemish and hair care products. MATERIALS AND METHODS: A literature analysis of plants of the IECIC list, present in French Polynesia was conducted. The most interesting plants from a cosmetic development standpoint were selected based on four main criteria, i.e. their traditional use in Polynesian cosmetic-related preparations, their biogeographical status, their phytochemistry of cosmetic interest, and lastly their availability and absence from the UICN list. Furthermore, a preliminary screening of antioxidant and anti-inflammatory activities was also performed on several extracts obtained. RESULTS: Eleven plants were chosen, and a compilation of multidisciplinary data emphasized each selected plant's potentiality. Traditional allegations showed uses ranging from dermatology such as wound healing or anti-inflammatory properties, to hair growth promoting preparations or even skin ligthening ones. Preliminary screenings were useful in narrowing the number of extracts to study. Literature-based data associated to traditional uses depicted how the remaining plants and plant parts could be developed for targeted cosmetic applications. CONCLUSIONS: A prospective approach of plants used traditionally for cosmetic purposes in French Polynesia gave insight on their development potential when paired with the appropriate multidisciplinary data. The eleven plants presented show promise in being developed sustainably as natural anti-aging or hair care products and as skin brightening agents.

Chemodiversity of Calophyllum inophyllum L. oil bioactive components related to their specific geographical distribution in the South Pacific region.

BACKGROUND: Different parts of the tree Calophyllum inophyllum L. (nuts, leaves, roots, bark, fruits, nut oil and resin) are used as traditional medicines and cosmetics in most of the Pacific Islands. The oil efficiency as a natural cure and in traditional cosmetics has been largely described throughout the South Pacific, which led us to investigate C. inophyllum's chemical and genetic diversity. A correlative study of the nut resin and leaf DNA from three distinct archipelagos in the South Pacific was carried out in order to identify diversity patterns in C. inophyllum across the South Pacific. METHODS: Calophyllum inophyllum plants were sampled from French Polynesia, New Caledonia and Fiji. We extracted tamanu oil (nut oil) resin for chemo-diversity studies and sampled leaf tissues for genetic studies. We applied an analysis method designed for small quantities (at a microscale level), and used High Performance Liquid Chromatography (HPLC) to establish the chemo-diversity of tamanu oil resin. In-house standards were co-eluted for qualitative determination. Genetic diversity was assessed using chloroplast barcoding markers (the Acetyl-CoA carboxylase (accD) gene and the psaA-ycf3 intergenic spacer region). RESULTS: Our HPLC analysis revealed 11 previously known tamanu oil constituents, with variability among plant samples. We also isolated and characterized two new neoflavonoids from tamanu oil resin namely, tamanolide E1 and E2 which are diastereoisomers. Although genetic analysis revealed low genetic variation, our multivariate analysis (PCA) of the tamanu oil resin chemical profiles revealed differentiation among geographic regions. CONCLUSION: We showed here that chromatographic analysis using formalized in-house standards of oil resin compounds for co-elution studies against oil resin samples could identify patterns of variation among samples of C. inophyllum, and discriminate samples from different geographical origins.

R. nukuhivensis acts by reinforcing skin barrier function, boosting skin immunity and by inhibiting IL-22 induced keratinocyte hyperproliferation.

Rauvolfia nukuhivensis is a well-known plant used for its wide range of beneficial effects in Marquesas islands. It is made up of diverse indole alkaloids and is used as traditional medicine for skin application. The actual mechanism behind the virtue of this plant is still unknown. Hence, in this study we aimed at deciphering the impact of R. nukuhivensis on skin immune system in context of (1) homeostasis, (2) pathogen infection and (3) inflammation. Here we show that R. nukuhivensis enhances cellular metabolic activity and wound healing without inducing cellular stress or disturbing cellular homeostasis. It reinforces the epithelial barrier by up-regulating hBD-1. Nevertheless, in pathogenic stress, R. nukuhivensis acts by preparing the immune system to be reactive and effective directly. Indeed, it enhances the innate immune response by increasing pathogens sensors such as TLR5. Finally, R. nukuhivensis blocks IL-22 induced hyperproliferation via PTEN and Filaggrin up-regulation as well as BCL-2 downregulation. In conclusion, this study provides evidence on the several cutaneous application potentials of R. nukuhivensis such as boosting the immune response or in restoring the integrity of the epithelial barrier.

Chemotypes and Biomarkers of Seven Species of New Caledonian Liverworts from the Bazzanioideae Subfamily.

Volatile components of seven species of the Bazzanioideae sub-family (Lepidoziaceae) native to New Caledonia, including three endemic species (Bazzania marginata, Acromastigum caledonicum and A. tenax), were analyzed by GC-FID-MS in order to index these plants to known or new chemotypes. Detected volatile constituents in studied species were constituted mainly by sesquiterpene, as well as diterpene compounds. All so-established compositions cannot successfully index some of them to known chemotypes but afforded the discovery of new chemotypes such as cuparane/fusicoccane. The major component of B. francana was isolated and characterized as a new zierane-type sesquiterpene called ziera-12(13),10(14)-dien-5-ol (23). In addition, qualitative intraspecies variations of chemical composition were very important particularly for B. francana which possessed three clearly defined different compositions. We report here also the first phytochemical investigation of Acromastigum species. Moreover, crude diethyl ether extract of B. vitatta afforded a new bis(bibenzyl) called vittatin (51), for which a putative biosynthesis was suggested.

Phenolic Profiling for Traceability of Vanilla ×tahitensis.

Vanilla is a flavoring recovered from the cured beans of the orchid genus Vanilla. Vanilla ×tahitensis is traditionally cultivated on the islands of French Polynesia, where vanilla vines were first introduced during the nineteenth century and, since the 1960s, have been introduced to other Pacific countries such as Papua New Guinea (PNG), cultivated and sold as "Tahitian vanilla," although both sensory properties and aspect are different. From an economic point of view, it is important to ensure V. ×tahitensis traceability and to guarantee that the marketed product is part of the future protected designation of the origin "Tahitian vanilla" (PDO), currently in progress in French Polynesia. The application of metabolomics, allowing the detection and simultaneous analysis of hundreds or thousands of metabolites from different matrices, has recently gained high interest in food traceability. Here, metabolomics analysis of phenolic compounds profiles was successfully applied for the first time to V. ×tahitensis to deepen our knowledge of vanilla metabolome, focusing on phenolics compounds, for traceability purposes. Phenolics were screened through a quadrupole-time-of-flight mass spectrometer coupled to a UHPLC liquid chromatography system, and 260 different compounds were clearly evidenced and subjected to different statistical analysis in order to enable the discrimination of the samples based on their origin. Eighty-eight and twenty three compounds, with a prevalence of flavonoids, resulted to be highly discriminant through ANOVA and Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) respectively. Volcano plot analysis and pairwise comparisons were carried out to determine those compounds, mainly responsible for the differences among samples as a consequence of either origin or cultivar. The samples from PNG were clearly different from the Tahitian samples that were further divided in two different groups based on the different phenolic patterns. Among the 260 compounds, metabolomics analysis enabled the detection of previously unreported phenolics in vanilla (such as flavonoids, lignans, stilbenes and other polyphenols).

Ethnobotanical survey of cosmetic plants used in Marquesas Islands (French Polynesia).

BACKGROUND: Cosmetic plants and their uses have often been neglected in ethnobotanical surveys which focus mainly on plants with medicinal or food uses. Thus, this survey was carried out to specifically investigate cosmetics in a small community and to establish a cosmetopoeia, based on the model of pharmacopoeia for medicinal plants. The geographic spread of the survey covered the Marquesas Islands, one of the five archipelagos of French Polynesia (Pacific Ocean). This archipelago was also recently investigated for its pharmacopoeia. METHODS: This survey is based on individual interviews of Marquesan informants on the islands of Tahiti (Society archipelago) and Nuku Hiva (Marquesas archipelago). The methodological approach was semi-directive with open-ended questions based on cosmetic criteria (application area, cosmetic use, plant). Before each interview, researchers and the informant signed a Prior Informed Consent (PIC). Quantitative analyses were performed using basic statistics and the indice of Fidelity Level (FL). RESULTS: Twenty-eight informants from five of the six inhabited Marquesan islands were interviewed and yielded more than 500 cosmetic recipes. Marquesan cosmetopoeia included 79 plant taxa, of which 5% are Marquesan endemics, 23% are indigenous, 28% are Polynesian introductions and 44% are modern introductions. Among the introduced species, half were cultivated whereas the other half were weedy species. Most of the plants were abundant and only eight species were considered rare, of which four were Marquesan endemics. Main cosmetic plants were identified through informant citations and fidelity levels, and included Calophyllum inophyllum, Cananga odorata, Citrus aurantiifolia, Cocos nucifera, Curcuma longa, Gardenia taitensis, Mentha spp., Ocimum basilicum, Rauvolfia nukuhivensis and Santalum insulare var. marchionense. The most referred application areas were skin, hair and private parts whereas the main cosmetic uses were perfume, hydration, medicinal care and healing. CONCLUSIONS: Through this survey, Marquesan cosmetopoeia was investigated in detail and uncovered a majority of introduced and abundant plants, and a minority of endemic and rare plants which required proper management to avoid future shortage. The well known perfumed coconut oil or monoi appeared as the main Marquesan cosmetic preparation either for the skin and the hair. Several plants and preparations warrant scientific investigations for their originality.

Changes in fatty acid composition in the giant clam Tridacna maxima in response to thermal stress.

Temperature can modify membrane fluidity and thus affects cellular functions and physiological activities. This study examines lipid remodelling in the marine symbiotic organism, Tridacna maxima, during a time series of induced thermal stress, with an emphasis on the morphology of their symbiont Symbiodinium First, we show that the French Polynesian giant clams harbour an important proportion of saturated fatty acids (SFA), which reflects their tropical location. Second, in contrast to most marine organisms, the total lipid content in giant clams remained constant under stress, though some changes in their composition were shown. Third, the stress-induced changes in fatty acid (FA) diversity were accompanied by an upregulation of genes involved in lipids and ROS pathways. Finally, our microscopic analysis revealed that for the giant clam's symbiont, Symbiodinium, thermal stress led to two sequential cell death processes. Our data suggests that the degradation of Symbiodinium cells could provide an additional source of energy to T maxima in response to heat stress.

Biological Activity of Polynesian Calophyllum inophyllum Oil Extract on Human Skin Cells.

Oil from the nuts of Calophyllum inophyllum, locally called "Tamanu oil" in French Polynesia, was traditionally used for wound healing and to cure various skin problems and ailments. The skin-active effect of "Tamanu oil emulsion" was investigated on human skin cells (keratinocytes and dermal fibroblasts) and showed cell proliferation, glycosaminoglycan and collagen production, and wound healing activity. Transcriptomic analysis of the treated cells revealed gene expression modulation including genes involved in the metabolic process implied in O-glycan biosynthesis, cell adhesion, and cell proliferation. The presence of neoflavonoids as bioactive constituents in Tamanu oil emulsion may contribute to these biological activities. Altogether, consistent data related to targeted histological and cellular functions brought new highlights on the mechanisms involved in these biological processes induced by Tamanu oil effects in skin cells.

Volatile Constituents of New Caledonian Frullania Species.

Volatile components of seven Frullania species (Frullaniaceae) from New Caledonia, including five endemic species (F. bella, F. scalaris, F. mamnmillosa, F. cornita and F. falsicornuta), were analyzed by GC-MS in order to index these plants to known chemotypes. Constituents detected in these Frullania species were mainly sesquiterpenes, as well as the bibenzyl dihydrognetin, and the flavonoid naringinin-5,7,4'-trimethyl ether. These compositions allowed an indexation of Frullania species from New Caledonia to cyclocolorenone, sesquiterpene lactone and bibenzyl chemotypes. In addition, qualitative intraspecies variations of chemical composition were very important and made indexation to known chemotypes very tricky. Moreover, two of the endemic liverworts did not possess any biomarker that linked to a known chemotype.