Analyzing Morphology, Metabolomics, and Transcriptomics Offers Invaluable Insights into the Mechanisms of Pigment Accumulation in the Diverse-Colored Labellum Tissues of Alpinia

Alpinia plants are widely cherished for their vibrant and captivating flowers. The unique feature of this genus lies in their labellum, a specialized floral structure resulting from the fusion of two non-fertile staminodes. However, the intricate process of pigment formation, leading to distinct color patterns in the various labellum segments of Alpinia, remains a subject of limited understanding. In this study, labellum tissues of two Alpinia species, A. zerumbet (yellow-orange flowers) and A. oxyphylla (white-purple flowers), were sampled and analyzed through morphological structure observation, metabolite analysis, and transcriptome analyses. We found that hemispherical/spherical epidermal cells and undulate cell population morphology usually display darker flower colors, while flat epidermal cells and cell populations usually exhibit lighter flower colors. Metabolomic analysis identified a high concentration of anthocyanins, particularly peonidin derivatives, in segments with orange and purple pigments. Additionally, segments with yellow pigments showed significant accumulations of flavones, flavanols, flavanones, and xanthophylls. Furthermore, our investigation into gene expression levels through qRT-PCR revealed notable differences in several genes that participated in anthocyanin and carotenoid biosynthesis among the four pigmented segments. Collectively, these findings offer a comprehensive understanding of pigmentation in Alpinia flowers and serve as a valuable resource for guiding future breeding efforts aimed at developing Alpinia varieties with novel flower colors.

Phylogenetic analysis and development of molecular markers for five medicinal Alpinia species based on complete plastome sequences

BACKGROUND

Alpinia species are widely used as medicinal herbs. To understand the taxonomic classification and plastome evolution of the medicinal Alpinia species and correctly identify medicinal products derived from Alpinia species, we systematically analyzed the plastome sequences from five Alpinia species. Four of the Alpinia species: Alpinia galanga (L.) Willd., Alpinia hainanensis K.Schum., Alpinia officinarum Hance, and Alpinia oxyphylla Miq., are listed in the Chinese pharmacopeia. The other one, Alpinia nigra (Gaertn.) Burtt, is well known for its medicinal values.

RESULTS

The four Alpinia species: A. galanga, A. nigra, A. officinarum, and A. oxyphylla, were sequenced using the Next-generation sequencing technology. The plastomes were assembled using Novoplasty and annotated using CPGAVAS2. The sizes of the four plastomes range from 160,590 bp for A. galanga to 164,294 bp for A. nigra, and display a conserved quadripartite structure. Each of the plastomes encodes a total of 111 unique genes, including 79 protein-coding, 28 tRNA, and four rRNA genes. In addition, 293-296 SSRs were detected in the four plastomes, of which the majority are mononucleotides Adenine/Thymine and are found in the noncoding regions. The long repeat analysis shows all types of repeats are contained in the plastomes, of which palindromic repeats occur most frequently. The comparative genomic analyses revealed that the pair of the inverted repeats were less divergent than the single-copy region. Analysis of sequence divergence on protein-coding genes showed that two genes (accD and ycf1) had undergone positive selection. Phylogenetic analysis based on coding sequence of 77 shared plastome genes resolves the molecular phylogeny of 20 species from Zingiberaceae. In particular, molecular phylogeny of four sequenced Alpinia species (A. galanga, A. nigra, A. officinarum, and A. oxyphylla) based on the plastome and nuclear sequences showed congruency. Furthermore, a comparison of the four newly sequenced Alpinia plastomes and one previously reported Alpinia plastomes (accession number: NC_048461) reveals 59 highly divergent intergenic spacer regions. We developed and validated two molecular markers Alpp and Alpr, based on two regions: petN-psbM and psaJ-rpl33, respectively. The discrimination success rate was 100 % in validation experiments.

CONCLUSIONS

The results from this study will be invaluable for ensuring the effective and safe uses of Alpinia medicinal products and for the exploration of novel Alpinia species to improve human health.

A Draft Genome of the Ginger Species Alpinia nigra and New Insights into the Genetic Basis of Flexistyly

Angiosperms possess various strategies to ensure reproductive success, such as stylar polymorphisms that encourage outcrossing. Here, we investigate the genetic basis of one such dimorphism that combines both temporal and spatial separation of sexual function, termed flexistyly. It is a floral strategy characterised by the presence of two morphs that differ in the timing of stylar movement. We performed a de novo assembly of the genome of Alpinia nigra using high-depth genomic sequencing. We then used Pool-seq to identify candidate regions for flexistyly based on allele frequency or coverage differences between pools of anaflexistylous and cataflexistylous morphs. The final genome assembly size was 2 Gb, and showed no evidence of recent polyploidy. The Pool-seq did not reveal large regions with high FST values, suggesting large structural chromosomal polymorphisms are unlikely to underlie differences between morphs. Similarly, no region had a 1:2 mapping depth ratio which would be indicative of hemizygosity. We propose that flexistyly is governed by a small genomic region that might be difficult to detect with Pool-seq, or a complex genomic region that proved difficult to assemble. Our genome will be a valuable resource for future studies of gingers, and provides the first steps towards characterising this complex floral phenotype.

Bioactive Molecules from the Alpinia Genus: A Comprehensive Review

BACKGROUND

Floral has diversity and unique nature due to the complex structure and component. Alpinia is an important genus of the Zingiberaceae family having complex taxonomical diversity. The presence of many unique bioactive molecules makes this genus, a pharmaceutically important genus. They provide a wide range of medicinal properties, including traditional remedies to modern therapeutic applications.

METHODS

Extracts of Alpinia mostly contain bioactive molecules and secondary metabolites such as polyphenolics, tannins, flavonoids and other therapeutically important compounds. These bioactive molecules are biologically active, treating against inflammation, cancer, arterial hypertension, and other deadly diseases.

RESULTS

These bioactive molecules can act as natural enzyme inhibitors for some of the deadly diseases and can block the pathway for metabolic activities. In addition, these genera have played a major role in multidisciplinary studies of phytochemistry, ethnobotany, and pharmacological aspects in day-to-day life.

CONCLUSION

Therefore, this review highlights the fewer known facts of the genus Alpinia in terms of bioactive molecules and its significant therapeutic applications to help in combating major diseases of humans.

Efficacy of DNA barcode internal transcribed spacer 2 (ITS 2) in phylogenetic study of Alpinia species from Peninsular Malaysia

Alpinia belongs to a large genus with many species found in Peninsular Malaysia. Several species of Alpinia exhibit important medicinal potential. However, progressive studies on the genus Alpinia were hampered by difficulties encountered in species identification. With the advancement achieved in genomic technology, more sensitive tools such as DNA barcoding were developed, which can be used for species identification. Internal Transcribe Spacer 2 (ITS2) is a DNA barcode which has proven to be a promising tool for species identification. The criterions of ITS2 efficacy namely universality and efficacy for species identification were tested on Alpinia species collected from Peninsular Malaysia. The results showed that a success rate of 96.97% was achieved using ITS2 for screening 11 species of Alpinia and an outgroup sample (Zingiber specatabile). Combined with 15 additional sequences from the Genbank for five Alpinia species, ITS2 demonstrated high species identification efficacy with 88.2% of species identified using phylogenetic and distance analysis. The analysis was further improved with the use of ITS2 secondary structure. The results of both criterions demonstrated the ability of ITS2 to successfully discriminate Alpinia species, which will help to improve species identification of Alpinia species in Peninsular Malaysia.

[Materiamedica literature study on medicinal properties and utility of four kinds of Alpinia Chinese medicines]

In order to explore the correlation between the medicinal properties，efficacy and application in the same genetic relationship，explain the scientific connotation of the medicinal properties and effects of traditional Chinese medicines(TCM)，promote the academic development of the theory of traditional Chinese medicines，and provide reference for the research and development of the traditional Chinese medicines of a same genus. In this paper, a literature study of ancient and modern works of Chinese herbal medicine was conducted to investigate the correlation between the properties, meridians tropism, efficacy and application of Alpinia officinarum， A. katsumadai， Galangae Fructus and Alpinae Oxyphyllae Fructus, four kinds of Alpinia Chinese medicines．The results showed that the similar properties of these four kinds of Alpinia Chinese medicines included that they were acrid, warm,and mainly getting into the spleen and stomach channels; the similar efficacies included that dispelling cold，relieving pain，warming stomach，anti-nausea，anti-diarrheal，reinforcing spleen to promote digestion and other effects; in application aspects, the similarities were that they were all mainly used in treatment of catching cold or spleen deficiency induced by abdominal pain，vomiting，diarrhea,diet indigestion, etc. indicating that phylogenetic relationship was closely related with the herbal properties, efficacy and application. It is an effective way to explore，collate and research traditional Chinese medicine by using plant phylogenetic relationships in exploring the internal relations and laws of TCM theories，material bases, pharmacological effects and clinical applications, also with a strong maneuverability to explain their scientific connotation.

An overview on cardamonin

Cardamonin, as shown by the increasing number of publications, has received growing attention from the scientific community due to the expectations toward its benefits to human health. In this study, research on cardamonin is reviewed, including its natural sources, health promoting aspects, and analytical methods for its determination. Therefore, this article hopes to aid current and future researchers on the search for reliable answers concerning cardamonin's value in medicine.

Alpinia: the gold mine of future therapeutics

Since prehistoric era, plant-derived drugs were much preferred due to their less side effects than drugs of synthetic origin. Bioassay-guided selection of active fraction of a plant extract and further isolation and characterization of the pure bioactive compounds are in practice in both academic and industrial research. Zingiberaceae, a medicinally important, ornamental, monocotyledonous family has potential members in the tribe Alpinieae, among which the genus Alpinia is studied under this current review due to its wide range of biomedical applications. The members in the genus possess many bioactive compounds against harmful microbes to deadly diseases like cancer by regulating the different signalling pathway systems. Several compounds have been discovered and found to deliver diversified biological efficacy either in vitro or in vivo against a range of diseases. The chemical profiling of the genus and investigation of crude essential oils and individual bioactive compounds towards the therapeutic importance in various disciplines have been documented in the current review.