Differential genetic responses to the stress revealed the mutation-order adaptive divergence between two sympatric ginger species.

BACKGROUND: Divergent genetic responses to the same environmental pressures may lead sympatric ecological speciation possible. Such speciation process possibly explains rapid sympatric speciation of island species. Two island endemic ginger species Zingiber kawagoii and Z. shuanglongensis was suggested to be independently originated from inland ancestors, but their island endemism and similar morphologies and habitats lead another hypothesis of in situ ecological speciation. For understanding when and how these two species diverged, intraspecific variation was estimated from three chloroplast DNA fragments (cpDNA) and interspecific genome-wide SNPs and expression differences after saline treatment were examined by transcriptomic analyses. RESULTS: Extremely low intraspecific genetic variation was estimated by cpDNA sequences in both species: nucleotide diversity π = 0.00002 in Z. kawagoii and no nucleotide substitution but only indels found in Z. shuanglongensis. Nonsignificant inter-population genetic differentiation suggests homogenized genetic variation within species. Based on 53,683 SNPs from 13,842 polymorphic transcripts, in which 10,693 SNPs are fixed between species, Z. kawagoii and Z. shuanglongensis were estimated to be diverged since 218~ 238 thousand generations ago (complete divergence since 41.5~ 43.5 thousand generations ago). This time is more recent than the time of Taiwan Island formation. In addition, high proportion of differential expression genes (DEGs) is non-polymorphic or non-positively selected, suggesting key roles of plastic genetic divergence in broaden the selectability in incipient speciation. While some positive selected DEGs were mainly the biotic and abiotic stress-resistance genes, emphasizing the importance of adaptive divergence of stress-related genes in sympatric ecological speciation. Furthermore, the higher proportional expression of functional classes in Z. kawagoii than in Z. shuanglongensis explains the more widespread distribution of Z. kawagoii in Taiwan. CONCLUSIONS: Our results contradict the previous hypothesis of independent origination of these two island endemic ginger species from SE China and SW China. Adaptive divergent responses to the stress explain how these gingers maintain genetic differentiation in sympatry. However, the recent speciation and rapid expansion make extremely low intraspecific genetic variation in these two species. This study arise a more probable speciation hypothesis of sympatric speciation within an island via the mutation-order mechanism underlying the same environmental pressure.

Very small relict populations suggest high extinction debt of gingers in primary forest fragments of a tropical city.

PREMISE OF THE STUDY: Tropical plant communities in fragmented forests are likely to experience an extinction debt, i.e., the habitat cannot support as many species as are present due to reduced habitat size and connectivity. There are few estimates of the number of species that represent extinction debt, and the number of extinctions over time has rarely been recorded. We recorded population sizes to assess threats and extinctions in gingers (sensu Zingiberales) in fragmented rainforest in Singapore, ca. 200 yr after fragmentation began. METHODS: We surveyed extant diversity and population sizes of gingers and used the results to estimate species survival. We critically assessed historic specimens to estimate initial extinctions and extinctions realized in present habitats. KEY RESULTS: We recorded 23 species, including five species previously presumed nationally extinct and four species omitted from the national checklist. The revised extinction rate is much lower than previously reported (12 vs. 37%). Most gingers have very small populations or miniscule ranges, implying that extinction debt has not been paid off. CONCLUSIONS: Ginger diversity remains high, but the number of species at immediate risk of extinction outnumber recorded extinctions. Although tropical forest fragments remain arks of plant diversity for a long time, extinction debt may be prevalent in all plant groups in Singapore. Slow relaxation of extinction debt should be explicitly identified as a conservation challenge and opportunity. For conserving plant diversity in tropical fragments, relaxation must be reversed through restoration of degraded landscapes and, where feasible, targeted ex situ conservation and planting.

Speciation dynamics and biogeography of Neotropical spiral gingers (Costaceae).

Species can arise via the divisive effects of allopatry as well as due to ecological and/or reproductive character displacement within sympatric populations. Two separate lineages of Costaceae are native to the Neotropics; an early-diverging clade endemic to South America (consisting of ca. 16 species in the genera Monocostus, Dimerocostus and Chamaecostus); and the Neotropical Costus clade (ca. 50 species), a diverse assemblage of understory herbs comprising nearly half of total familial species richness. We use a robust dated molecular phylogeny containing most of currently known species to inform macroevolutionary reconstructions, enabling us to examine the context of speciation in Neotropical lineages. Analyses of speciation rate revealed a significant variation among clades, with a rate shift at the most recent common ancestor of the Neotropical Costus clade. There is an overall predominance of allopatric speciation in the South American clade, as most species display little range overlap. In contrast, sympatry is much higher within the Neotropical Costus clade, independent of node age. Our results show that speciation dynamics during the history of Costaceae is strongly heterogeneous, and we suggest that the Costus radiation in the Neotropics arose at varied geographic contexts.

MS-Based Metabolite Profiling of Aboveground and Root Components of Zingiber mioga and Officinale.

Zingiber species are members of the Zingiberaceae family, and are widely used for medicinal and food purposes. In this study aboveground and root parts of Zingiber mioga and Zingiber officinale were subjected to metabolite profiling by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) in order to characterize them by species and parts and also to measure bioactivities. Both primary and secondary metabolites showed clear discrimination in the PCA score plot and PLS-DA by species and parts. Tetrahydrocurcumin, diarylheptanoid, 8-gingerol, and 8-paradol were discriminating metabolites between Z. mioga and Z. officinale that were present in different quantities. Eleven flavonoids, six amino acids, six organic acids, four fatty acids, and gingerenone A were higher in the aboveground parts than the root parts. Antioxidant activities were measured and were highest in the root part of Z. officinale. The relatively high contents of tetrahydrocurcumin, diarylheptanoid, and galanganol C in the root part of Z. officinale showed highly positive correlation with bioactivities based on correlation assay. On the basis of these results, we can suggest different usages of structurally different parts of Zingiber species as food plants.

Precision Research on Ginger: The Type of Ginger Matters.

Ginger is a widely consumed spice and possesses numerous pharmacological properties. However, studies addressing the efficacy of ginger in humans have been inconsistent. Many confounding factors need to be considered when evaluating the health effects from ginger against chronic diseases, especially the levels of bioactive components in the ginger formulations used in human trials. Gingerols, the major compounds in fresh ginger, are liable to dehydrate and convert to shogaols, the major compounds in dried ginger, as a result of the instability of ß-hydroxyl ketone when exposed to heat and/or acidic conditions. As a result of various heating and processing methods, the concentrations of gingerols and shogaols in ginger products vary significantly. Increasing evidence has shown that gingerols and shogaols have different bioactivities, molecular targets, and metabolic pathways, suggesting the importance of identifying the optimal oral ginger composition for a specific disease. In this perspective, we highlighted differences in the composition between fresh ginger and dry ginger, bioactivities, molecular targets, and metabolic pathways of gingerols and shogaols as well as future perspectives regarding precision research on ginger.

Timing the radiations of leaf beetles: hispines on gingers from latest cretaceous to recent.

Stereotyped feeding damage attributable solely to rolled-leaf hispine beetles is documented on latest Cretaceous and early Eocene ginger leaves from North Dakota and Wyoming. Hispine beetles (6000 extant species) therefore evolved at least 20 million years earlier than suggested by insect body fossils, and their specialized associations with gingers and ginger relatives are ancient and phylogenetically conservative. The latest Cretaceous presence of these relatively derived members of the hyperdiverse leaf-beetle clade (Chrysomelidae, more than 38,000 species) implies that many of the adaptive radiations that account for the present diversity of leaf beetles occurred during the Late Cretaceous, contemporaneously with the ongoing rapid evolution of their angiosperm hosts.

Defence transcriptome profiling of Zingiber zerumbet (L.) Smith by mRNA differential display.

Soft rot is a serious disease in ginger (Zingiber of?cinale Roscoe),imposing a considerable economic loss annually in all ginger-producing countries. In this study,mRNA differential display was employed to identify genes whose expression was altered in a soft rot-resistant accession of Zingiber zerumbet (L.) Smith,a wild relative of ginger, in response to Pythium aphanidermatum (Edson) Fitzp.,which is the principal causative agent of soft-rot disease in ginger. Analysis using 68 primer combinations identified 70 differentially expressed transcript-derived fragments (TDFs),of which 34 TDFs were selected for further analysis following reverse northern screening. Cloning and sequence characterization of the 34 TDFs yielded a total of 54 distinct clones. Functional categorization of these clones revealed seven categories,of which the defence/stress/signalling group was the largest,with clones homologous to genes known to be actively involved in various pathogenesis-related functions in other plant species.The significance of these genes in relation to the resistance response in Z.zerumbet is discussed. This study has provided a pool of candidate genes for detailed molecular dissection of the defence mechanisms in Z.zerumbet and for accessing wild genetic resources for the transgenic improvement of ginger.

Development of SCAR (sequence-characterized amplified region) markers as a complementary tool for identification of ginger (Zingiber officinale Roscoe) from crude drugs and multicomponent formulations.

Zingiber officinale Roscoe (common or culinary ginger) is an official drug in Ayurvedic, Indian herbal, Chinese, Japanese, African and British Pharmacopoeias. The objective of the present study was to develop DNA-based markers that can be applied for the identification and differentiation of the commercially important plant Z. officinale Roscoe from the closely related species Zingiber zerumbet (pinecone, bitter or 'shampoo' ginger) and Zingiber cassumunar [cassumunar or plai (Thai) ginger]. The rhizomes of the other two Zingiber species used in the present study are morphologically similar to that of Z. officinale Roscoe and can be used as its adulterants or contaminants. Various methods, including macroscopy, microscopy and chemoprofiling, have been reported for the quality control of crude ginger and its products. These methods are reported to have limitations in distinguishing Z. officinale from closely related species. Hence, newer complementary methods for correct identification of ginger are useful. In the present study, RAPD (random amplification of polymorphic DNA) analysis was used to identify putative species-specific amplicons for Z. officinale. These were further cloned and sequenced to develop SCAR (sequence-characterized amplified region) markers. The developed SCAR markers were tested in several non-Zingiber species commonly used in ginger-containing formulations. One of the markers, P3, was found to be specific for Z. officinale and was successfully applied for detection of Z. officinale from Trikatu, a multicomponent formulation.

Tight species cohesion among sympatric insular wild gingers (Asarum spp. Aristolochiaceae) on continental islands: Highly differentiated floral characteristics versus undifferentiated genotypes.

The Amami Island group of the Ryukyu Archipelago, Japan, harbors extensive species diversity of Asarum in a small landmass. The fine-scale population genetic structure and diversity of nine insular endemic Asarum species were examined using nuclear DNA microsatellite loci and ITS sequences. High population genetic diversity (HS = 0.45-0.79) was estimated based on the microsatellites, implying outcrossing of Asarum species within populations accompanied by inbreeding. Bayesian clustering analyses revealed that species were divided into three robust genetic clusters and that the species within each cluster had a homogeneous genetic structure, indicating incomplete lineage sorting. This conclusion was supported by an ITS phylogeny. The degree of genetic differentiation among species was very low both within and between clusters (FST = 0.096-0.193, and 0.096-0.266, respectively). Although species can be crossed artificially to produce fertile hybrids, our results indicate that there is very little evidence of hybridization or introgression occurring among species in the wild, even within stands composed of multiple sympatric species. The highly differentiated floral morphology of the studied species is likely to impose reproductive isolation between them and maintain their integrity in the wild. A lack of genetic differentiation between sympatric species suggests that speciation within this group occurred rapidly and recently.

Metabolic profiling and phylogenetic analysis of medicinal Zingiber species: Tools for authentication of ginger (Zingiber officinale Rosc).

Phylogenetic analysis and metabolic profiling were used to investigate the diversity of plant material within the ginger species and between ginger and closely related species in the genus Zingiber (Zingiberaceae). In addition, anti-inflammatory data were obtained for the investigated species. Phylogenetic analysis demonstrated that all Zingiber officinale samples from different geographical origins were genetically indistinguishable. In contrast, other Zingiber species were significantly divergent, allowing all species to be clearly distinguished using this analysis. In the metabolic profiling analysis, the Z. officinale samples derived from different origins showed no qualitative differences in major volatile compounds, although they did show some significant quantitative differences in non-volatile composition, particularly regarding the content of [6]-, [8]-, and [10]-gingerols, the most active anti-inflammatory components in this species. The differences in gingerol content were verified by HPLC. The metabolic profiles of other Zingiber species were very different, both qualitatively and quantitatively, when compared to Z. officinale and to each other. Comparative DNA sequence/chemotaxonomic phylogenetic trees showed that the chemical characters of the investigated species were able to generate essentially the same phylogenetic relationships as the DNA sequences. This supports the contention that chemical characters can be used effectively to identify relationships between plant species. Anti-inflammatory in vitro assays to evaluate the ability of all extracts from the Zingiber species examined to inhibit LPS-induced PGE(2) and TNF-alpha production suggested that bioactivity may not be easily predicted by either phylogenetic analysis or gross metabolic profiling. Therefore, identification and quantification of the actual bioactive compounds are required to guarantee the bioactivity of a particular Zingiber sample even after performing authentication by molecular and/or chemical markers.

Time-Domain Nuclear Magnetic Resonance Investigation of Water Dynamics in Different Ginger Cultivars.

Different ginger cultivars may contain different nutritional and medicinal values. In this study, a time-domain nuclear magnetic resonance method was employed to study water dynamics in different ginger cultivars. Significant differences in transverse relaxation time T2 values assigned to the distribution of water in different parts of the plant were observed between Henan ginger and four other ginger cultivars. Ion concentration and metabolic analysis showed similar differences in Mn ion concentrations and organic solutes among the different ginger cultivars, respectively. On the basis of Pearson's correlation analysis, many organic solutes and 6-gingerol, the main active substance of ginger, exhibited significant correlations with water distribution as determined by NMR T2 relaxation, suggesting that the organic solute differences may impact water distribution. Our work demonstrates that low-field NMR relaxometry provides useful information about water dynamics in different ginger cultivars as affected by the presence of different organic solutes.

Assessment of genetic diversity among 16 promising cultivars of ginger using cytological and molecular markers.

Ginger (Zingiber officinale Roscoe) is an economically important plant, valued all over the world. The existing variation among 16 promising cultivars as observed through differential rhizome yield (181.9 to 477.3 g) was proved to have a genetic basis using different genetic markers such as karyotype, 4C nuclear DNA content and random amplified polymorphic DNA (RAPD). The karyotypic analysis revealed a differential distribution of A, B, C, D and E type of chromosomes among different cultivars as represented by different karyotype formulas. A significant variation of 4C DNA content was recorded in ginger at an intraspecific level with values ranging from 17.1 to 24.3 pg. RAPD analysis revealed a differential polymorphism of DNA showing a number of polymorphic bands ranging from 26 to 70 among 16 cultivars. The RAPD primers OPC02, OPA02, OPD20 and OPN06 showing strong resolving power were able to distinguish all 16 cultivars. The extent of genetic diversity among these cultivars was computed through parameters of gene diversity, sum of allele numbers per locus and Shannon's information indices. Cluster analysis, Nei's genetic similarity and genetic distances, distribution of cultivars into special distance classes and principal coordinate analysis and the analysis of molecular variance suggested a conspicuous genetic diversity among different cultivars studied. The genetic variation thus detected among promising cultivars of ginger has significance for ginger improvement programs.

Whole plastome sequences from five ginger species facilitate marker development and define limits to barcode methodology.

Plants from the Zingiberaceae family are a key source of spices and herbal medicines. Species identification within this group is critical in the search for known and possibly novel bioactive compounds. To facilitate precise characterization of this group, we have sequenced chloroplast genomes from species representing five major groups within Zingiberaceae. Generally, the structure of these genomes is similar to the basal angiosperm excepting an expansion of 3 kb associated with the inverted repeat A region. Portions of this expansion appear to be shared across the entire Zingiberales order, which includes gingers and bananas. We used whole plastome alignment information to develop DNA barcodes that would maximize the ability to differentiate species within the Zingiberaceae. Our computation pipeline identified regions of high variability that were flanked by highly conserved regions used for primer design. This approach yielded hitherto unexploited regions of variability. These theoretically optimal barcodes were tested on a range of species throughout the family and were found to amplify and differentiate genera and, in some cases, species. Still, though these barcodes were specifically optimized for the Zingiberaceae, our data support the emerging consensus that whole plastome sequences are needed for robust species identification and phylogenetics within this family.

Inhibition of angiotensin-1-converting enzyme activity by two varieties of ginger (Zingiber officinale) in rats fed a high cholesterol diet.

Angiotensin-1-converting enzyme (ACE) inhibitors are widely used in the treatment of cardiovascular diseases. This study sought to investigate the inhibitory effect of two varieties of ginger (Zingiber officinale) commonly consumed in Nigeria on ACE activity in rats fed a high cholesterol diet. The inhibition of ACE activity of two varieties of ginger (Z. officinale) was investigated in a high cholesterol (2%) diet fed to rats for 3 days. Feeding high cholesterol diets to rats caused a significant (P<.05) increase in the ACE activity. However, there was a significant (P<.05) inhibition of ACE activity as a result of supplementation with the ginger varieties. Rats that were fed 4% white ginger had the greatest inhibitory effect as compared with a control diet. Furthermore, there was a significant (P<.05) increase in the plasma lipid profile with a concomitant increase in malondialdehyde (MDA) content in rat liver and heart tissues. However, supplementing the diet with red and white ginger (either 2% or 4%) caused a significant (P<.05) decrease in the plasma total cholesterol, triglyceride, very low density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol levels, and in MDA content in the tissues. Conversely, supplementation caused a significant (P<.05) increase in plasma high-density lipoprotein-cholesterol level when compared with the control diet. Nevertheless, rats fed 4% red ginger had the greatest reduction as compared with control diet. In conclusion, both ginger varieties exhibited anti-hypercholesterolemic properties in a high cholesterol diet fed to rats. This activity of the gingers may be attributed to its ACE inhibitory activity. However, white ginger inhibited ACE better in a high cholesterol diet fed to rats than red ginger. Therefore, both gingers could serve as good functional foods/nutraceuticals in the management/treatment of hypertension and other cardiovascular diseases.

Avaliação da atividade larvicida do óleo essencial do Zingiber officinale Roscoe (gengibre) frente ao mosquito Aedes aegypti / Evaluation of the larvicidal effectof the essential oil of Zingiber officinale Roscoe (ginger) against the mosquito Aedes aegypti

RESUMO Este trabalho analisa o efeito larvicida do óleo Zingiber officinale Roscoe contra larvas em terceiro estágio do mosquito Aedes aegypti. Extraiu-se quantitativamente o óleo essencial por hidrodestilação e calculou-se a CL50 do óleo, a partir dos métodos de Reed-Muench e Pizzi, respectivamente. O óleo essencial obteve CL50 de 76,07 (±2,24) μg mL-1 e rendimento de 0,52% m/v. Os resultados indicam que o óleo essencial avaliado é composto por substâncias que propiciam efeito larvicida contra Aedes aegypti.

ABSTRACT This study analyzes the larvicidal effect of the oil of Zingiber officinale Roscoe against larvae in third stage of the mosquito Aedes aegypti (Linnaeus 1792). The essential oil was extracted quantitatively by hydrodistillation and we calculated the oil’s LC50 from Reed-Muench (1938) and Pizzi (1950) methods, respectively. The essential oil obtained LC50 of 76.07 (±2.24) ug mL-1, and yield of 0.52% m/v. The results indicate that the essential oil assessed has substances that provide larvicidal effect against Aedes aegypti.

Atividade antimicrobiana do óleo essencial de rizomas de açafrão (Curcuma longa L. ) e gengibre (Zingiber officinale Roscoe) frente a salmonelas entéricas isoladas de frango resfriado / Antimicrobial activity of essential oil from Curcuma longa and Zingiber officinale rhizomes against enteric Salmonella isolated from chicken

Objetivou-se com este trabalho identificar, quantificar os constituintes, e avaliar a atividade antibacteriana dos óleos essenciais extraídos de rizomas de açafrão (Curcuma longa L.) e gengibre (Zingiber officinale Roscoe) cultivados nas condições de Manaus/AM frente a 14 salmonelas entéricas isoladas de frango resfriado. A extração dos óleos essenciais foi realizada utilizando-se aparelho tipo Clevenger e a composição determinada por Cromatografia Gasosa acoplada a Espectrometria de Massas (CG-MS). A atividade antibacteriana foi realizada com o emprego de técnica de microdiluição em caldo. O óleo essencial de gengibre se mostrou expressivamente mais eficiente do que o óleo de açafrão, tanto em termos de ação bacteriostática (concentração inibitória mínima de 2500 a 5000 µg.mL-1) quanto bactericida (concentração bactericida mínima de 5000 a 10000 µg.mL-1) observando-se variação apenas em duas as amostras em termos de resistência a ação bactericida deste óleo. Assim, o óleo essencial de gengibre, representa uma alternativa para o controle de Salmonella enterica, entretanto, demais estudos abordando o sinergismo com alimentos são indicados.

The objective of this work was to identify, quantify constituents and evaluate the antibacterial activity of essential oils from rhizomes of turmeric (Curcuma longa L.) and ginger (Zingiber officinale Roscoe) grown under conditions of Manaus/AM front of enteric salmonella isolated from chilled poultry. The extraction of essential oils was performed using the Clevenger type apparatus and composition determined by Gas Chromatography coupled to Mass Spectrometry (GC-MS). The antibacterial activity was performed with the use of microdilution broth. The essential oil of ginger proved significantly more efficient than tumeric oil, both in terms of bacteriostatic action (minimum inhibitory concentration 2500-5000 mg µg mL-1) and bactericidal (minimum bactericidal concentration 5000-10000 mg µg mL-1) observing changes in only two samples in terms of resistance to bactericidal activity of this oil. Thus, the essential oil of ginger, is an alternative for the control of Salmonella enterica, however, other studies addressing the synergism with food are indicated.