Search

Bone homeostasis is maintained by balancing bone formation and bone resorption, but an imbalance between them is associated with various bone-related diseases such as osteoporosis and rheumatoid arthritis. We found that 5,6-dehydrokawain (DK) and dihydro-5,6-dehydrokawain (DDK), which were isolated as promising compounds from Alpinia zerumbet rhizomes, promote differentiation of osteoblastic MC3T3-E1 cells. DK and DDK increased the alkaline phosphatase activity and matrix mineralization of MC3T3-E1 cells. DK exerts larger effects than DDK. The gene expression of runt-related transcription factor 2 and osterix, which are essential transcription factors in the early period of osteoblast differentiation, was significantly increased by DK treatment. The mRNA level of distal-less homeobox 5 was also enhanced by DK treatment, and DK activated the p38 mitogen-activated protein kinase pathway. Therefore, DK may have clinical potential for preventing osteoporosis, and could be considered as a potential anabolic therapeutic agent.

Essential oils are new natural medicines, which have been studied extensively in recent years. In this paper, the chemical composition of the essential oil from Alpinia zerumbet leaves and its ability to modulate the activity of aminoglycoside antibiotics is reported. The essential oil was extracted by hydrodistillation and analyzed by gas chromatography (GC) and GC–mass spectrometry (GC/MS). The antibacterial activity of the essential oil alone or in association with aminoglycosides was determined by a microdilution test against twelve strains (standards and multi-resistant clinical isolates obtained from sputum and wounds), seven Gram negative and five Gram positive. The major components identified by GC/MS were 4-terpineol (32.9 ± 4.0%), 1,8-cineole (21.4 ± 1.2%), γ-terpinolene (10.0 ± 1.8%) and sabinene (7.1 ± 4.6%), with a strong predominance of monoterpenes. The results indicated that the multi-resistant clinical isolates Staphylococcus aureus 358 and Escherichia coli 27 were more sensitive to the e...

The beneficial effects of the phytochemical compounds in fruits and vegetables have been extrapolated mainly from in vitro studies or short-term dietary supplementation studies. Recent approaches using animal models of Caenorhabditis elegans are becoming quite popular, and in this regard the effects of Alpinia zerumbet leaf extract (ALP) on C. elegans lifespan were investigated under both normal and stress conditions. ALP significantly increased, mean lifespan by 22.6%, better than the positive control, resveratrol. Furthermore, both under thermal and oxidative stressed conditions, ALP increased the survival rate significantly better than quercetin. Further studies indicated that the significant longevity-extending effects of ALP on C. elegans can be attributed to its in vitro free-radical scavenging effects and its upregulation of stress-resistance proteins, including superoxide dismutase 3 (SOD-3) and heat-shock protein (HSP-16.2). These results suggest that phytochemical compounds in A. zerumbet have beneficial effects on the lifespan of C. elegans, and that they can be used as a source of dietary supplements for aging and age-related diseases.

In utilization of Alpinia zerumbet (Pers.) Burtt and Smith (Zingiberaceae) (AZ), usually the angiocarps are discarded without further use.We speculate whether the angiocarps could show hypolipidemic effect.Several diets were prepared: Alpinia seed powder (ASP); Alpinia seed powder/husk (ASH): 40/60; and Alpinia seed essential oil (ASO): 0.01-0.10%. Sprague-Dawley rats divided into 11 groups were fed these diets for 8 weeks and tested for the hypolipidemic bioactivity.The fecal neutral cholesterol excretion was increased, and the serum total triglyceride (TG) was significantly reduced from 153.7 mg/dL in the high-fat group (H) to 114.3-119.8 mg/dL by ASO; to 116.3-147.9 mg/dL by ASP; and to 116.2-145.3 mg/dL by ASH. Activity of superoxide dismutase (SOD) and glutathione peroxidase (GPX) were almost unaffected. The high-density lipoprotein (HDL) levels were mostly raised by ASO to 180.3-200.8 mg/dL. The lowdensity lipoprotein (LDL) levels were mostly reduced to 66.8-82.6 mg/dL by ASH. The level of arachidonic acid was mostly raised to 0.50-0.60% by ASO, compared with 0.37% of group H. More importantly, the significant reduction in hepatic TG and total cholesterol (TC) implicated a crucial liver protective effect.ASP and ASH consisted of high crude-fiber content, while ASO consisted of seed essential oil. Both the seed essential oil and the whole powder of AZ previously had been reported to possess potent hypolipidemic bioactivity. Conclusively, the hypolipidemic effect can be attributed to the combined effect of the essential oil and the crude fiber.

Plant leaves are commonly used in folk medicine and food industry. Their volatile composition is an important determinant in such applications. However, to properly assess the quality of volatiles, proper analytic tools must be utilised. Accordingly, the static headspace technique was used to evaluate the main volatiles emitted from in vitro-grown Alpinia zerumbet plants cultured with indole-3-acetic acid, thidiazuron, benzyladenine or kinetin, under standard physical conditions, as compared to those of field-grown donor plants. Although the leaf aroma of the donor plants was found to be a complex mixture, mainly consisting of sabinene, α and γ-terpinene, 1,8-cineole and caryophyllene, volatile analyses from most of the in vitro samples only revealed the presence of sabinene and caryophyllene. Many alkanes were found in the aromas after treating plantlets with cytokinins. Histochemical analysis of leaf sections was also carried out. Secretory cells found in the epidermis and mesophyll showed a strong positive reaction to lipophilic compounds using Oil red and Nile blue reagents. These findings demonstrated how in vitro conditions may alter the quality of volatiles in micropropagation systems, while leaf anatomy analysis revealed a large quantity of oil cells in the mesophyll as a constant feature responsible for the production of volatile compounds in both donor and in vitro-grown plants.

The essential oil of the rhizome of Alpinia speciosa K. Schum. collected from Dehradun, India, was isolated by hydrodistillation and analyzed by GC and GC/MS. Sixty-six compounds representing 95.98% of the oil were identified. The major constituents of the essential oil of the rhizome were terpinen-4-ol (15.4%), 1,8-cineole (11.1%) and T-cadinol (8.8%). The oil showed antibacterial activity against Micrococcus luteus, Streptococcus mutans, Bacillus subtilis, Staphylococcus aureus (Gram-positive), Salmonella typhi and Pseudomonas aeruginosa (Gram-negative) using the well diffusion method.

Firesh leaves of Alpinia zerumbet and A. purpurata (Zingiberaceae) were collected in Rio de Janeiro city and subjected to hydrodistillation; their chemical composition was analyzed by GC/MS. These species are used as ornamental plants and in folk medicine. Variations in the leaf oils content and composition of A. zerumbet were found between April and August 2005. In April, the main constituents identiified in leaf oil of A. zerumbet were terpinen-7-al (40.5%) and sabinene hydrate (15.4%); in August, the major components identiified were terpinen-4-ol (29.4%) and 1,8-cineole (23.1%). Leaf oil of A. purpurata was rich in P-pinene (34.7%) and α-pinene (11.8%).

A new labdane-type diterpene, named zerumin, was isolated from the seeds of the Chinese medicinal plant, Alpinia zerumbet. The structure was elucidated by NMR spectroscopic methods including heteronuclear multiple-bond multiple-quantum coherence (HMBC).