Phytosynthesis of silver nanoparticles using aqueous sandalwood (Santalum album L.) leaf extract: Divergent effects of SW-AgNPs on proliferating plant and cancer cells.

The biogenic approach for the synthesis of metal nanoparticles provides an efficient eco-friendly alternative to chemical synthesis. This study presents a novel route for the biosynthesis of silver nanoparticles using aqueous sandalwood (SW) leaf extract as a source of reducing and capping agents under mild, room temperature synthesis conditions. The bioreduction of Ag+ to Ago nanoparticles (SW-AgNPs) was accompanied by the appearance of brown color, with surface plasmon resonance peak at 340-360 nm. SEM, TEM and AFM imaging confirm SW-AgNP's spherical shape with size range of 10-32 nm. DLS indicates a hydrodynamic size of 49.53 nm with predominant negative Zeta potential, which can contribute to the stability of the nanoparticles. FTIR analysis indicates involvement of sandalwood leaf derived polyphenols, proteins and lipids in the reduction and capping of SW-AgNPs. XRD determines the face-centered-cubic crystalline structure of SW-AgNPs, which is a key factor affecting biological functions of nanoparticles. This study is novel in using cell culture methodologies to evaluate effects of SW-AgNPs on proliferating cells originating from plants and human cancer. Exposure of groundnut calli cells to SW-AgNPs, resulted in enhanced proliferation leading to over 70% higher calli biomass over control, enhanced defense enzyme activities, and secretion of metabolites implicated in biotic stress resistance (Crotonyl isothiocyanate, Butyrolactone, 2-Hydroxy-gamma-butyrolactone, Maltol) and plant cell proliferation (dl-Threitol). MTT and NRU were performed to determine the cytotoxicity of nanoparticles on human cervical cancer cells. SW-AgNPs specifically inhibited cervical cell lines SiHa (IC50-2.65 ppm) and CaSki (IC50-9.49 ppm), indicating potential use in cancer treatment. The opposing effect of SW-AgNPs on cell proliferation of plant calli (enhanced cell proliferation) and human cancer cell lines (inhibition) are both beneficial and point to potential safe application of SW-AgNPs in plant cell culture, agriculture and in cancer treatment.

Santalum Genus: phytochemical constituents, biological activities and health promoting-effects.

Santalum genus belongs to the family of Santalaceae, widespread in India, Australia, Hawaii, Sri Lanka, and Indonesia, and valued as traditional medicine, rituals and modern bioactivities. Sandalwood is reported to possess a plethora of bioactive compounds such as essential oil and its components (α-santalol and ß-santalol), phenolic compounds and fatty acids. These bioactives play important role in contributing towards biological activities and health-promoting effects in humans. Pre-clinical and clinical studies have shown the role of sandalwood extract as antioxidant, anti-inflammatory, antibacterial, antifungal, antiviral, neuroleptic, antihyperglycemic, antihyperlipidemic, and anticancer activities. Safety studies on sandalwood essential oil (EO) and its extracts have proven them as a safe ingredient to be utilized in health promotion. Phytoconstituents, bioactivities and traditional uses established sandalwood as one of the innovative materials for application in the pharma, food, and biomedical industry.

A Comparison of the Composition of Selected Commercial Sandalwood Oils with the International Standard.

Sandalwood oils are highly desired but expensive, and hence many counterfeit oils are sold in high street shops. The study aimed to determine the content of oils sold under the name sandalwood oil and then compare their chromatographic profile and α- and ß santalol content with the requirements of ISO 3518:2002. Gas chromatography with mass spectrometry analysis found that none of the six tested "sandalwood" oils met the ISO standard, especially in terms of α-santalol content. Only one sample was found to contain both α- and ß-santalol, characteristic of Santalum album. In three samples, valerianol, elemol, eudesmol isomers, and caryophyllene dominated, indicating the presence of Amyris balsamifera oil. Another two oil samples were found to be synthetic mixtures: benzyl benzoate predominating in one, and synthetic alcohols, such as javanol, polysantol and ebanol, in the other. The product label only gave correct information in three cases: one sample containing Santalum album oil and two samples containing Amyris balsamifera oil. The synthetic samples described as 100% natural essential oil from sandalwood are particularly dangerous and misleading to the consumer. Moreover, the toxicological properties of javanol, polysantol and ebanol, for example, are unknown.

Sandalwood seed oil ameliorates hepatic insulin resistance by regulating the JNK/NF-κB inflammatory and PI3K/AKT insulin signaling pathways.

Sandalwood (santalum spicatum) seed oil (SSO) is rich in ximenynic acid. The aim of the present study was to investigate the effect of SSO on high-fat/high-sucrose diet (HFHSD) induced insulin resistance (IR) in comparison with fish oil (FO), sunflower oil (SO) and linseed oil (LO). Fifty male Sprague-Dawley rats were randomly divided into five dietary groups: standard chow diet (controls), HFHSD plus 7% SSO, HFHSD plus 7% FO, HFHSD plus 7% SO and HFHSD plus 7% LO. After 12 weeks of feeding, the rats were sacrificed, and the serum parameters, hepatic lipids and underlying molecular mechanisms were studied. SSO, FO or LO significantly prevented glucose intolerance, hyperglycaemia, obesity, and hepatic lipid accumulation, and decreased the homeostasis model assessment of IR (HOMA-IR) and the serum levels of pro-inflammatory factors (IL-6, IL-1ß and TNF-α) compared with SO. In addition, SSO activated the PI3K/AKT insulin signaling pathway and down-regulated the JNK/NF-κB inflammatory signaling pathway in the liver. In summary, our results proved that SSO exerted an ameliorative effect on IR by regulating the hepatic inflammation related blockage of the insulin signaling pathway in the rats.

Santalum album extract exhibits neuroprotective effect against the TLR3-mediated neuroinflammatory response in human SH-SY5Y neuroblastoma cells.

Neuroinflammation is an inflammatory response in the nervous system that is associated with various neurological diseases including Alzheimer's diseases and others. Many studies evaluated the anti-inflammatory potential of Santalum album (S. album) extract, but none of them analyzed its effects against neuroinflammatory response in vitro. In addition, the precise mechanism underlying the anti-inflammatory effect of the extract has not yet been elucidated. Therefore, in this study, we investigated the effect of S. album extract on modulation of toll-like receptor 3 (TLR3) agonist polyinosnic-polycytidylic acid (PolyI:C)-induced neuroinflammatory response in human neuroblastoma cells. The TLR3-mediated immune response was differentially modulated by S. album extract in SH-SY5Y cells. In addition, treatment of cells with the conditioned medium (CM) of S. album extract significantly increased the mRNA levels of IFN-ß, IFN-α, MxA and OAS-1 and decreased IL-6, CXCL8, CCL2 and IP-10. S. album extract has indirectly affected the expression of IFNs and inflammatory cytokines in SH-SY5Y cells. Furthermore, the extract was able to modulate PolyI:C-induced inflammatory response in Caco2 cells. Overall, S. album was capable to attenuate PolyI:C-induced neuroinflammatory effect through the induction of TLR2, TLR4 and the modulation of TLR negative regulators of the TRAF3, IRF3 and NF-κB pathways.

Cadinane sesquiterpenoids isolated from Santalum album using a screening program for Wnt signal inhibitory activity.

Upon screening compounds having Wnt signal inhibitory activity through evaluating TCF/ß-catenin transcriptional (TOP) activity, eight cadinane sesquiterpenoids, including three new compounds (1-3), were isolated from wood extracts of Santalum album (Santalaceae). Structures of compounds 1-3 were elucidated by spectral data to have a cadinane skeleton with an aromatic ring. Of the eight compounds isolated, compound 4, identified as mansonone I, was found to be active against TOP, having an IC50 of 1.2 µM.

Sedative and hypnotic effects of compound Anshen essential oil inhalation for insomnia.

BACKGROUNDS: The chemical composition of many essential oils indicates that they have sedative and hypnotic effects, but there is still a lack of systematic studies on the sedative and hypnotic effects of essential oils. In addition, aromatherapy does not seem to have the side effects of many traditional psychotropic substances, which is clearly worthwhile for further clinical and scientific research. The clinical application of essential oils in aromatherapy has received increasing attention, and detailed studies on the pharmacological activities of inhaled essential oils are increasingly needed. HYPOTHESIS/PURPOSE: As insomniacs are usually accompanied by symptoms of depression and anxiety of varying degrees, based on the theory of aromatherapy of Traditional Chinese Medicine, this experiment is to study a Compound Anshen essential oil that is compatible with Lavender essential oil, Sweet Orange essential oil, Sandalwood essential oil and other aromatic medicine essential oils with sedative and hypnotic effects, anti-anxiety and anti-depression effects. To study the sedative and hypnotic effects of Compound Anshen essential oil inhaled and the main chemical components of Compound Anshen essential oil, and to compare and analyze the pharmacodynamics of diazepam, a commonly used drug for insomnia. METHODS: The Open field test and Pentobarbital-induced sleep latency and sleep time experiments were used to analyze and compare the sedative and hypnotic effects of inhaling Compound Anshen essential oil and the administration of diazepam on mice. The changes of 5-HT and GABA in mouse brain were analyzed by Elisa. The main volatile constituents of Compound Anshen essential oil were analyzed by gas chromatography-mass spectrometry (GC-MS). RESULTS: Inhalation of Compound Anshen essential oil can significantly reduce the spontaneous activity of mice, reduce latency of sleeping time and prolong duration of sleeping time. The results of enzyme-linked immunosorbent assay showed that Compound Anshen essential oil can increase the content of 5-HT and GABA in mouse brain. The main volatile chemical constituents of the Compound Anshen essential oil are D-limonene (24.07%), Linalool (21.98%), Linalyl acetate (15.37%), α-Pinene (5.39%), and α-Santalol (4.8%). CONCLUSION: The study found that the inhalation of Compound Anshen essential oil has sedative and hypnotic effect. This study provides a theoretical basis for further research and development of the sedative and hypnotic effects of Compound Anshen essential oil based on the theory of aromatherapy.

[Progress in biosynthesis of santalene and santalol].

Santalene and santalol are the main components of valuable perfume sandalwood essential oil, and have good antibacterial, anti-oxidation and anti-tumor activities. Commercial sandalwood essential oil is mainly extracted from sandalwood tree that grows slowly and is difficult to cultivate. In addition, the extraction recovery of sandalwood essential oil from sandalwood tree is too low to meet the market demand. These factors make sandalwood essential oil expensive. An option is to use genetic engineering and molecular biological methods to heterologously express related synthase of santalene and santalol in microbial host. In this paper, the biosynthesis progress of santalene and santalol synthase, as well as the optimization of mevalonate metabolic pathways in the hosts are summarized. Furthermore, the strategies of applying protein engineering technology to carry out orthomutation of santalene synthase were also discussed, to provide reference for the optimal biosynthesis of santalene and santalol.

Antifungal and Ichthyotoxic Sesquiterpenoids from Santalum album Heartwood.

In our continuing study on a survey of biologically active natural products from heartwood of Santalum album (Southwest Indian origin), we newly found potent fish toxic activity of an n-hexane soluble extract upon primary screening using killifish (medaka) and characterized α-santalol and ß-santalol as the active components. The toxicity (median tolerance limit (TLm) after 24 h at 1.9 ppm) of α-santalol was comparable with that of a positive control, inulavosin (TLm after 24 h at 1.3 ppm). These fish toxic compounds including inulavosin were also found to show a significant antifungal effect against a dermatophytic fungus, Trichophyton rubrum. Based on a similarity of the morphological change of the immobilized Trichophyton hyphae in scanning electron micrographs between treatments with α-santalol and griseofulvin (used as the positive control), inhibitory effect of α-santalol on mitosis (the antifungal mechanism proposed for griseofulvin) was assessed using sea urchin embryos. As a result, α-santalol was revealed to be a potent antimitotic agent induced by interference with microtubule assembly. These data suggested that α-santalol or sandalwood oil would be promising to further practically investigate as therapeutic agent for cancers as well as fungal skin infections.

Sesquiterpene Variation in West Australian Sandalwood (Santalum spicatum).

West Australian sandalwood (Santalum spicatum) has long been exploited for its fragrant, sesquiterpene-rich heartwood; however sandalwood fragrance qualities vary substantially, which is of interest to the sandalwood industry. We investigated metabolite profiles of trees from the arid northern and southeastern and semi-arid southwestern regions of West Australia for patterns in composition and co-occurrence of sesquiterpenes. Total sesquiterpene content was similar across the entire sample collection; however sesquiterpene composition was highly variable. Northern populations contained the highest levels of desirable fragrance compounds, α- and ß-santalol, as did individuals from the southwest. Southeastern populations were higher in E,E-farnesol, an undesired allergenic constituent, and low in santalols. These trees generally also contained higher levels of α-bisabolol. E,E-farnesol co-occurred with dendrolasin. Contrasting α-santalol and E,E-farnesol chemotypes revealed potential for future genetic tree improvement. Although chemical variation was evident both within and among regions, variation was generally lower within regions. Our results showed distinct patterns in chemical diversity of S. spicatum across its natural distribution, consistent with earlier investigations into sandalwood population genetics. These results are relevant for plantation tree improvement and conservation efforts.

Analysis of essential oils and fragrances with a new generation of highly inert gas chromatographic columns coated with ionic liquids.

In the fields of essential oils and fragrances, samples often consist of mixtures of compounds with similar structural and physical characteristics (e.g. mono- and sesquiterpenoids), whose correct identification closely depends on the synergic combination of chromatographic and mass spectral data. This sample complexity means that new GC stationary phases with different selectivities are continually being investigated. Ionic liquids (ILs) are of great interest as GC stationary phases in this field because of their selectivity (significantly different than that of currently phases) and their high temperature stability. A first generation of IL GC columns was found to be competitive when applied to these field, in terms of selectivity and efficiency, compared to conventional columns (polydimethylsiloxane, (e.g. OV-1), methyl-polysiloxane 5%-phenyl (e.g. SE-52), 7%-cyanopropyl, 7%-phenyl polysiloxane (e.g. OV-1701), and polyethylen glycol (e.g. PEG-20M). However, these columns showed significant activity towards polar or active analytes, which primarily affected their quantitative performance. A new generation of highly-inactive columns coated with three of the most widely-used ionic liquid GC stationary phases has recently been introduced; these phases are SLB-IL60i (1,12-di(tripropylphosphonium) dodecane bis(trifluoromethylsulfonyl) imide [NTf2], SLB-IL76i (tri-(tripropylphosphonium-hexanamido)-triethylamine [NTf2]), and SLB-IL111i (1,5-di (2,3-dimethyllimidazolium) pentane [NTf2]). This study carefully tested the new inert IL columns, in view of their routine application in the fragrance and essential oil fields. They were found to have unusually high selectivity, comparable to that of first-generation IL columns, while their inertness and efficiency were competitive with those of currently-used conventional columns. The IL column performance of first and second generations was compared, through the quali-quantitative analysis of components in a group of different complexity samples; these included the Grob test, a standard mixture of "suspected" skin allergens, and the essential oils of chamomile and sandalwood.

Evaluation of Ubtan - A traditional indian skin care formulation.

ETHNOPHARMACOLOGICAL RELEVANCE: 'Ubtan' is a traditional herbal formulation in the Indian system of medicine being used in India and its subcontinent for a long time. Several commercial skin care formulations are marketed throughout this region as the name of Ubtan. Therefore, it is worthwhile to evaluate Ubtan in respect of its efficacy as skin care formulation. AIM OF THE STUDY: The present study was designed for the preparation of Ubtan and standardization through the chromatographic techniques by using suitable phyto-markers. Further, its antioxidant, sun protection factor (SPF) and anti-tyrosinase potential have been explored. MATERIALS AND METHODS: Four in-house formulations (UF-1, UF-2, UF-3 and UF-4) were prepared by mixing a varied quantity of each powdered plants, i.e. turmeric (Curcuma longa L.), Chickpea (Cicer arietinum L.) and sandalwood (Santalum album L.). Optimization of the formulations was made by evaluating its biological activity through in vitro assay. Evaluation of physicochemical properties of the optimized formulation (UF-1) has been carried out by analysis of pH, flow properties and stability. Moreover, RP-HPLC (reverse phase - high performance liquid chromatography) and HPTLC (high performance thin layer chromatography) standardization of UF-1 was performed for its quantitative and qualitative analysis. RESULTS: Ubtan formulations (UF-1to UF-4) showed free radical scavenging and ferric reducing potential. It may be due to its high phenolic and flavonoid content. Statistically, significant Pearson's correlation (r) was confirmed the positive correlation between phenolic content and SPF of the formulations. The tyrosinase inhibition study indicated that the formulations showed both diphenolase and monophenolase inhibitory activity. Among four formulations, UF-1 showed notable biological activity (p<0.05). The content of curcumin and ascorbic acid was found to be 1.6% and 2.1% w/w respectively in UF-1 through RP-HPLC estimation. Physiochemical properties of the UF-1 exhibited good flow rate and aqueous solubility. From the stability studies, it can be anticipated that the UF-1 was stable at 40°C for longer periods. Microbial load count and heavy metal content (lead-Pb, arsenic-As, mercury-Hg and cadmium-Cd) of the formulation was also within the permissible limit of a pharmacopeial standard. CONCLUSION: This scientific exploration helps to set the quality and safety standard of traditional cosmetic formulation, Ubtan and its further use as an herbal skin care product.

A Pilot Study on the Physiological Effects of Three Essential Oils in Humans.

In the present study, the physiological effects on 32 humans exposed to experimental stress provoked by inhalation of the essential oils of East Indian sandalwood (Santalum album L.), Western Australian sandalwood (Santalum spicatum R.Br.) and lavender (Lavandula angustifolia MILL.) were investigated. During individual testing sessions, several saliva samples were collected, blood pressure was regularly measured and parameters of the autonomic nervous system (heart rate, skin conductance response) were continuously monitored. Salivary cortisol, as an endocrine stress indicator, was determined by time- resolved fluoroimmunoassay. Statistical analyses evidenced that the tested sandalwood essential oils significantly reduced systolic blood pressure, especially during the recreation phase. This finding corresponds with a distinct reduction of salivary cortisol levels during recreation in the Western Australian sandalwood oil compared with the control. In conclusion, the results demonstrate that essential oils can alleviate the physiological reactions to psychological stress and facilitate recovery after exposition to stress.

ZnO Nanoparticles-Red Sandalwood Conjugate: A Promising Anti-Diabetic Agent.

With the advances in nanoscience and nanotechnology the interest of researchers has expanded to interdisciplinary domain like bio-medical applications. Among such domains, one of the most important areas explored meticulously is the development of promising solutions in diabetes therapeutics. The disease associated with metabolic disorder, is one of the major challenges, due to its ever-increasing number of patients. The adverse effects of the synthetic enzymes like α-amylase and α-glucosidase inhibitors have invited many scientists to develop promising contender with minimal side-effects. On the other hand, Zinc has strong role in insulin synthesis, storage and secretion and thus its deficiency can be related to diabetes. In this context we have explored natural extract of Red Sandalwood (RSW) as a potent anti-diabetic agent, in conjugation with ZnO nanoparticles. ZnO nanoparticles have been synthesized via soft chemistry routes and duly characterized for their phase formation with the help of X-ray diffraction technique and Field-Emission Scanning Electron Microscopy. These monodispersed nanoparticles, -20 nm in size, were further conjugated to RSW extract. The conjugation chemistry was studied via Fourier transform infrared spectroscopy, UV-visible spectroscopy. Extract loading percentage was found from thermo-gravimetric analysis. 65% of the RSW extract was found conjugated to the ZnO nanoparticles. The anti-diabetic activity was assessed with the help of like α-amylase and α-glucosidase inhibition assay with murine pancreatic and small intestinal extracts. It was observed that the conjugated ZnO-RSW nanoparticles showed excellent activity against the crude murine pancreatic glucosidase as compared to the individual ZnO nanoparticles and the RSW extract. The ZnO-RSW conjugate showed 61.93% of inhibition while the bare ZnO nanoparticles and RSW showed 21.48% and 5.90% respectively.

Performance evaluation of a versatile multidimensional chromatographic preparative system based on three-dimensional gas chromatography and liquid chromatography-two-dimensional gas chromatography for the collection of volatile constituents.

The present research deals with the multi-collection of the most important sesquiterpene alcohols belonging to sandalwood essential oil, as reported by the international regulations: (Z)-α-santalol, (Z)-α-trans bergamotol, (Z)-ß-santalol, epi-(Z)-ß-santalol, α-bisabolol, (Z)-lanceol, and (Z)-nuciferol. A versatile multidimensional preparative system, based on the hyphenation of liquid and gas chromatography techniques, was operated in the LC-GC-GC-prep or GC-GC-GC-prep configuration, depending on the concentration to be collected from the sample, without any hardware or software modification. The system was equipped with a silica LC column in combination with polyethylene glycol-poly(5% diphenyl/95% dimethylsiloxane)-medium polarity ionic liquid or ß-cyclodextrin based GC stationary phases. The GC-GC-GC-prep configuration was exploited for the collection of four components, by using a conventional split/splitless injector, while the LC-GC-GC-prep approach was applied for three low abundant components (<5%), in order to increase the quantity collected within a single run, by the LC injection of a high sample amount. All target compounds, whose determination is hampered by the unavailability of commercial standards, were collected at milligram levels and with a high degree of purity (>87%).

Anticancer Effects of Sandalwood (Santalum album).

Effective management of tumorigenesis requires development of better anticancer agents with greater efficacy and fewer side-effects. Natural products are important sources for the development of chemotherapeutic agents and almost 60% of anticancer drugs are of natural origin. α-Santlol, a sesquiterpene isolated from Sandalwood, is known for a variety of therapeutic properties including anti-inflammatory, anti-oxidant, anti-viral and anti-bacterial activities. Cell line and animal studies reported chemopreventive effects of sandalwood oil and α-santalol without causing toxic side-effects. Our laboratory identified its anticancer effects in chemically-induced skin carcinogenesis in CD-1 and SENCAR mice, ultraviolet-B-induced skin carcinogenesis in SKH-1 mice and in vitro models of melanoma, non-melanoma, breast and prostate cancer. Its ability to induce cell-cycle arrest and apoptosis in cancer cells is its most reported anticancer mechanism of action. The present review discusses studies that support the anticancer effect and the mode of action of sandalwood oil and α-santalol in carcinogenesis.

Synergistic effect of fragrant herbs in Japanese scent sachets.

The sedative activity of eight aromatic natural medicines that are traditionally used in Japanese scent sachets was examined using an open field test with mice. Galangal (Kaempferia galanga), patchouli (Pogostemon cablin), sandalwood (Santalum album), spikenard (Nardostachys chinensis), cinnamon (Cinnamomum cassia), clove (Syzygium aromaticum), star anise (Illicium verum), and borneol (Dryobalanops aromatica) distilled oils were used. These natural medicines have various pharmacological effects. For example, galangal has insecticidal activity and clove extracts possess strong total antioxidant activity. Aromatherapy, a well-known complementary medicine system that uses inhalation, has recently attracted much attention. The sedative activity of inhaled aromatic compounds or essential oils has been examined by measuring the spontaneous motor activity of mice in an open field test. The galangal, patchouli, sandalwood, spikenard, and borneol oils showed significant sedative effects. The effect was stronger for a mixture of the five oils than for any of the single oils. This suggests that the oil mixture may have synergistic activity. Sedative activity was not observed when inactive oils (cinnamon, clove, and star anise) were added to the mixture of the five active oils.

The transcriptome of sesquiterpenoid biosynthesis in heartwood xylem of Western Australian sandalwood (Santalum spicatum).

The fragrant heartwood oil of West Australian sandalwood (Santalum spicatum) contains a mixture of sesquiterpene olefins and alcohols, including variable levels of the valuable sesquiterpene alcohols, α- and ß-santalol, and often high levels of E,E-farnesol. Transcriptome analysis revealed sequences for a nearly complete set of genes of the sesquiterpenoid biosynthetic pathway in this commercially valuable sandalwood species. Transcriptome sequences were produced from heartwood xylem tissue of a farnesol-rich individual tree. From the assembly of 12,537 contigs, seven different terpene synthases (TPSs), several cytochromes P450, and allylic phosphatases were identified, as well as transcripts of the mevalonic acid and methylerythritol phosphate pathways. Five of the S. spicatum TPS sequences were previously unknown. The full-length cDNA of SspiTPS4 was cloned and the enzyme functionally characterized as a multi-product sesquisabinene B synthase, which complements previous characterization of santalene and bisabolol synthases in S. spicatum. While SspiTPS4 and previously cloned sandalwood TPSs do not explain the prevalence of E,E-farnesol in S. spicatum, the genes identified in this and previous work can form a basis for future studies on natural variation of sandalwood terpenoid oil profiles.

Anti-diarrhoeal activity of methanol extract of Santalum album L. in mice and gastrointestinal effect on the contraction of isolated jejunum in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Santalum album L., namely Sandalwood, honored as "Green Gold", is a traditional Chinese herb which has the effects of anti-diarrhoeal and antibacterial activity. But there is limit scientific study on its activity and mechanism in gastrointestinal disorders. MATERIALS AND METHODS: in vivo, after intragastric administration, the methanol extract of Sandalwood (SE) (200, 400 and 800 mg/kg) were studied in castor oil-induced diarrhoea mice. By the test of small intestinal hyperfunction induced by neostigmine, SE was studied on gastrointestinal transit including gastric emptying and small intestinal motility. Meanwhile, in vitro, the effects of SE (0.02, 0.05, 0.1, 0.2, 0.3, 0.4 mg/mL) on the isolated tissue preparations of rat jejunum were also investigated. The rat jejunum strips were pre-contracted with acetylcholine (Ach; 10(-6)M), 5-hydroxytryptamine (5-HT, 200 µM) or potassium chloride (KCl; 60 mM) and tested in the presence of SE. In addition, the possible myogenic effect was analyzed in the pretreatment of the jejunum preparations with SE or verapamil in Ca(2+)-free high-K(+) (60 mM) solution containing EDTA. RESULTS: At doses of 200, 400 and 800 mg/kg, SE showed significant anti-diarrhoeal activity against castor oil-induced diarrhoea as compared with the control. At the same doses, it also inhibited the gastric emptying and small intestinal motility in the mice of which small intestinal hyperfunction induced by neostigmine. It caused inhibitory effects on the spontaneous contraction of rat-isolated jejunum in dose-dependent manner ranging from 0.02 to 0.4 mg/mL, and it also relaxed the Ach-induced, 5-HT-induced and K(+)-induced contractions. SE shifted the Ca(2+) concentration-response curves to right, similar to that caused by verapamil (0.025 mM). CONCLUSIONS: These findings indicated that SE played a spasmolytic role in gastrointestinal motility which was probably mediated through inhibition of muscarinic receptors, 5-HT receptors and calcium influx. All these results provide pharmacological basis for its clinical use in gastrointestinal tract.

Suppression of lipopolysaccharide-stimulated cytokine/chemokine production in skin cells by sandalwood oils and purified α-santalol and ß-santalol.

Medicinally, sandalwood oil (SO) has been attributed with antiinflammatory properties; however, mechanism(s) for this activity have not been elucidated. To examine how SOs affect inflammation, cytokine antibody arrays and enzyme-linked immunosorbent assays were used to assess changes in production of cytokines and chemokines by co-cultured human dermal fibroblasts and neo-epidermal keratinocytes exposed to lipopolysaccharides and SOs from Western Australian and East Indian sandalwood trees or to the primary SO components, α-santalol and ß-santalol. Lipopolysaccharides stimulated the release of 26 cytokines and chemokines, 20 of which were substantially suppressed by simultaneous exposure to either of the two sandalwood essential oils and to ibuprofen. The increased activity of East Indian SO correlated with increased santalol concentrations. Purified α-santalol and ß-santalol equivalently suppressed production of five indicator cytokines/chemokines at concentrations proportional to the santalol concentrations of the oils. Purified α-santalol and ß-santalol also suppressed lipopolysaccharide-induced production of the arachidonic acid metabolites, prostaglandin E2, and thromboxane B2, by the skin cell co-cultures. The ability of SOs to mimic ibuprofen non-steroidal antiinflammatory drugs that act by inhibiting cyclooxygenases suggests a possible mechanism for the observed antiinflammatory properties of topically applied SOs and provides a rationale for use in products requiring antiinflammatory effects.