The sequences of the plastid gene rpl16 and the rpl16-rpl14 spacer region allow discrimination among six species of Scutellaria

Leveraging plastomes for comparative analysis and phylogenomic inference within Scutellarioideae (Lamiaceae)

Scutellaria, or skullcaps, are medicinally important herbs in China, India, Japan, and elsewhere. Though Scutellaria is the second largest and one of the more taxonomically challenging genera within Lamiaceae, few molecular systematic studies have been undertaken within the genus; in part due to a paucity of available informative markers. The lack of informative molecular markers for Scutellaria hinders our ability to accurately and robustly reconstruct phylogenetic relationships, which hampers our understanding of the diversity, phylogeny, and evolutionary history of this cosmopolitan genus. Comparative analyses of 15 plastomes, representing 14 species of subfamily Scutellarioideae, indicate that plastomes within Scutellarioideae contain about 151,000 nucleotides, and possess a typical quadripartite structure. In total, 590 simple sequence repeats, 489 longer repeats, and 16 hyper-variable regions were identified from the 15 plastomes. Phylogenetic relationships among the 14 species representing four of the five genera of Scutellarioideae were resolved with high support values, but the current infrageneric classification of Scutellaria was not supported in all analyses. Complete plastome sequences provide better resolution at an interspecific level than using few to several plastid markers in phylogenetic reconstruction. The data presented here will serve as a foundation to facilitate DNA barcoding, species identification, and systematic research within Scutellaria, which is an important medicinal plant resource worldwide.

Production of Bacalin, Bacalein and Wogonin in Hairy Root Culture of American Skullcap (Scutellaria lateriflora)by Auxin Treatment

ABSTRACT: The hairy root culture of American Skullcap (Scutellaria lateriflora) was studied to investigate the biomass and flavonoids content (baicalin, baicalein and wogonin) in response of various auxin concentrations.The growth rates of the hairy roots varied significantly only at IBA 0.1 mg/L and for all other auxin treatments did not vary significantly. The biomass of hairy roots was 8% higher when treated with IBA 0.1 mg/L and biomass was almost similar and slightly lower levels when treated with various IAA concentration and NAA, respectively. However, the auxins treatments responsed positively to increase flavone production in American Skullcaphairy root culture. The auxin indole-3-butyric acid (IBA) at 1 mg/L performed the best for the accumulation of baicalin and wogonin. The auxin IBA at 1 mg/L accumulated 1.64 and 2.92 times higher baicalin and wogonin, respectively compared to control treatment. Meanwhile, the highest levels of baicalein were observed for hair root cultures in the presence of 1-naphthaleneacetic acid (NAA) at 0.1 mg/L achieving 2.38 times higher than that of accumulated in the control. These findings indicate that hairy root cultures of S. lateriflorausing liquid 1/2MS medium supplemented with auxin could be a valuable alternative approach for flavonoid production.

Preliminary survey of taxonomical problems, pharmacognostical characteristics, and chloroplast DNA polymorphisms of the folk medicinal herb Artemisia campestris from the Ryukyu Islands, Japan

Artemisia campestris L. (Compositae) occurs naturally along the coastline of the Ryukyu Islands and has been traditionally used as a folk medicine for the treatment of liver and kidney disorders. The authors obtained specimens from the Ishigaki and Kume Islands of the Ryukyu Islands, Japan, and from the USA. A survey of the literature revealed that the Japanese name for A. campestris is Niitaka-yomogi or Riukiu-yomogi. Two distinct overall plant-form phenotypes were identified: an erect phenotype with long, upright, and straight main axis and assurgent branches; and a prostrate phenotype, having branches that are longer than the main axis and which grow along the ground. Except for the number of ray flowers, most of the flower head characters in the erect phenotypes were significantly larger than those in the prostrate phenotypes. In this experiment, the flower heads contained only small amounts of either capillarisin (<0.01-0.11 of the dry weight, % DW) and 6,7-dimethylesculetin (<0.01-0.30% DW), or none at all. DNA polymorphisms at two sites of the rpl16-rpl14 spacer region (nucleotide position 181-189 and 291-300 from the 5' end) revealed the existence of four different haplotypes. The number of adenines at nucleotide positions 291-300 appeared to be polymorphic within A. campestris from the Ryukyu Islands. Conversely, geographic differences between specimens from the Ryukyu Islands and USA manifested as a nine-base deletion at nucleotide positions 181-189. From a pharmacognostical context, the use of A. campestris flower heads as a substitute for Artemisiae capillaris Flos is not effective.