Unicellular Trichomes Research Articles

Leaf morphoanatomical character variation of Gyrinops and Aquilaria (Thymelaeaceae) in Indonesia region at east Wallace line

There are seven species of Gyrinops and two species of Aquilaria (Thymelaeaceae), which are distributed in Eastern Indonesia at the east of the Wallace line. The anatomical character of the paradermal tissue, midrib and petiole were the important characteristics possessed by plants that can be used as data for identification. The purpose of this article was to study leaf morphoanatomical character variation of Gyrinops and Aquilaria in Indonesia Region at East Wallace Line. The Gyrinops specimen used in the research was the collection of the Agarwood Study Center, Universitas Mataram, Mataram, Indonesia. The paradermal slide was made with the whole-mount slide method and the slide cross-section of midrib and petiole was made by using a hand-free section. Their preparation process used a permanent slide method and mounted with glycerine jelly. Based on the results of the research conducted, it can be seen that the anatomical characters of paradermal tissues, midrib and petiole of Gyrinops and Aquilaria have general characteristics such as hypostomatic leaves, stomata type anomocytic, non-glandular and unicellular trichome. While other characters of structure paradermal, midrib and petiole could be used as a taxonomy diagnostic marker to identify at the level genus and species on Gyrinops and Aqilaria.

Pharmacognostic characteristics and antioxidant studies of Psydrax subcordata (DC.) Bridson

• Psydrax subcordata is a small flowering tree or shrub that grows in central and western Africa belonging to the family Rubiaceae. • Pharmacognostic (organoleptic, macroscopic, microscopic and physico-chemical) parameters of P. subcordata leaves can serve as simple means to identification and also for the quality control of the plant material. • Antioxidants are endogenous or exogenous substances that interact with and neutralize free radicals • Numerous stomata of paracytic type occurred on both the upper and lower surfaces but more abundantly on the lower surface of the plant P. subcordata . • P. subcordata leaf microscopic features include shiny, circular and irregularly shaped calcium oxalate crystals, fibres, unicellular trichomes and starch granules. Psydrax is a genus of flowering plants in the family Rubiaceae with over 80 accepted plant species. Psydrax subcordata is a small tree or shrub that grows in Central and Western Africa countries where its roots, leaves and stem are used locally by traditional healers for medicinal purposes. These local uses include the treatment of malaria fever, inflammation, haemorrhoids, enteritis, stomach ulcer, epilepsy and cardiovascular ailments. This study was carried out to examine parameters for identification of the plant and investigate potential antioxidant activity. The macroscopic, microscopic and physico-chemical characteristics of the leaf were determined using standard procedures. Antioxidant activity was also investigated using five different antioxidant models namely; DPPH Radical scavenging activity, FRAP assay, Total antioxidant capacity (Phosphomolybdenum) assay, Hydrogen peroxide scavenging assay and Reducing power assay. The leaves of the plant are simple, broad and entire. Ovate in shape, shortly acuminate apex and subcordate at the leaf base. The dark green upper surface is hairy or pubescent while greyish-green lower surface is sparely pubescent. The leaf showed microscopic mono-cyclic calcium oxalate crystals, unicellular trichomes, xylem vessels and other diagnostic features. The in-vitro antioxidant assays conducted, suggested that the extract contains antioxidant compounds. The characteristic macroscopic, microscopic and physico-chemical parameters evaluated for the plant sample can be used in rapid identification, authentication and for the quality control of the plant material before they are used for treatment and manufacturing of herbal medicines. The results of the antioxidant study showed that the extract exhibited potent antioxidant activity.

Floral gland diversity in Pleurothallidinae (Epidendroideae–Orchidaceae)

Pleurothallidinae are a diverse Neotropical subtribe of Orchidaceae pollinated by Diptera. Here, our goal was to map how myophily and deceptive sapromyophily appears in the Pleurothallidinae’ lineages, analyzing the morphological and topological variations of the floral glands in a phylogenetic framework. Scanning electron and light microscopy were employed to examine the glands located on the ovary, sepals, and labellum of twenty-eight species belonging to the subtribe. Colleters could be considered as a new morphological synapomorphy due to their widespread occurrence on the external ovary wall, while multicellular and unicellular oil-producing glands were also identified on this organ for the first time. Myophilous or nectariferous species usually have unicellular trichomes on the labellum and this trait appears in four lineages restricted to the basal nodes of the phylogenetic tree. Sapromyophilous species normally possess sticky-exudate glands and/or osmophores, the former being considered as an evolutionary novelty in Pleurothallidinae lineages. Sepaline osmophores are commonly found in myophilous and sapromyophilous species. Osmophores constituted by unicellular secretory trichomes mostly occur on the labellum and probably have a unique relationship with directional evolution related to sapromyophily. The diversity in the secretion of the labellum's glands includes monosaccharides, polysaccharides, and lipophilic compounds, which lead us to propose that heterochronic events are involved to the synthesis of these compounds by pleurothallidineaen species.

Pharmacognostic Evaluation and Anti-Diabetic Activity of Ethanol Extract of Triumfetta cordifolia A. Rich (Tiliaceae) Leaves

Aim: The study was aimed at evaluating some pharmacognostic parameters and investigates the anti-diabetic activity of ethanol extract of Triumfetta cordifolia leaf
 Methods: The pharmacognostic profiling of Triumfetta cordifolia leaves was carried out using some standard pharmacognostic tools for crude drug standardization such as qualitative and quantitative microscopy, analytical evaluation and phytochemical screening. The plant material was extracted using cold maceration method in ethanol and fractionation was carried out using n-hexane, ethylacetate and butanol. The acute toxicity study was done following standard method. Diabetes in albino wistar rats was intraperitoneally induced using 120 mg/kg body weight of alloxan monohydrate. The diabetic rats where treated with 200 and 400 mg/kg body weight of the crude extract and 400mg/kg of each of the fractions. Glibenclamide was used as the standard drug (5 mg/kg) and diabetic rats without treatment as negative control. The procedure was also similarly performed using the non-diabetic rats. The administration of all treatments was done orally, once daily for 21 days and blood sera of the blood samples from rats across the groups were collected at the end of the treatment period and the concentrations of Aspartate aminotransferase (AST), Alkaline phosphatase (ALP) and Alanine aminotransferase (ALT) were evaluated.
 Results: The results of the qualitative microscopic evaluation of Triumfetta cordifolia leaf revealed paracytic stomata, unicellular trichomes, wavy wall epidermal cells and prismatic calcium oxalate. Quantitative microscopic study gave 23.67 ± 0.58 stomata number, 0.023 ± 0.00058 stomata index, 18.33 ± 1.53 Palisade ratio and 10.67 ± 0.58 vein-islet number while the analytical standard revealed 9.3 total ash, 3.5 water soluble ash and 1.34 acid insoluble ash. The phytochemical analysis revealed the presence of alkaloids, glycosides, Tannins, flavonoids steroids and terpenoids in the Triumfetta cordifolia leaves ethanol extract (TCEE). A significant reduction (P≤0.05) in fasted blood sugar level of diabetic rats was observed during treatment with Triumfetta cordifolia leaves extract and the blood sugar level lowering potential was comparable to the glibenclamide’s group. There was improvement of body weight in TCEE treated groups and ethylacetate fraction group. The Leaf extract of Triumfetta cordifolia showed a high significant (P≤0.05) ameliorating potential on liver’s degenerating hepatocytes evidenced by the comparable reduction in AST, ALT and ALP levels with the glibenclamide’s and diabetic’s groups.
 Conclusion: The overall results showed that Triumfetta cordifolia leaf possesses blood sugar lowering and liver hepatocytes regenerating potentials while the pharmacognostic profiling of the plant can serve as a reference and guide for future researchers.

Trichomes Morphological Diversity in Some Species from Related Tribes of Asteraceae Family in Iraq

This study includedepidermal appendages characters of ten species belongingto the familyAsteraceae.Most of the studied species are characterized by eglandular, glandular, trichomesand papillae which are variable according to itskind, number of cells, shape, dimensions, characteristicsof surrounding cells, wall thickness and the position. Results showed that all species included glandular and eglandulartrichomes exceptCosmos bipinnatus, Ecliptaprostrate, andEupatoriumcannabinum that lacked in glandular trichomes and were based on their specific details.Trichomes were divided into different groups. The glandular ones involved sessile glandular or group multicellular and the head wasmace-shaped or rounded.Whereaseglandulartrichomes are classified into various groups,unicellular trichomes group with obtuse or acute apex or with tuft shape or dendroid, dicellular.Trichome group uniserriate or biserriate, and multicellular trichome group which is widely different in their shapes, dimensions, number of cell and the position. Papillae distributed on stem, corolla, and stigma have triangular-shape with acute apex or finger-like shape with obtuse apex.Hence,trichomes reveal a taxonomic importance in species identification and determine the relationships among them in their tribes.

Pharmacognostic and physicochemical analysis of the leaves of Fadogia andersonii Robyns (Rubiaceae)

Fadogia andersonii has long been used in Africa in treatment of diseases including inflammation, arthritis, malaria and as aphrodisiac. The use and demand of this medicinal plants has been growing over long period of time. This study was carried out to determine some important pharmacognostic parameters of F. andersonii leaf. Evaluation of the fresh, powdered leaves was carried out to determine the macro-morphological, qualitative and quantitative microscopic, chemomicroscopic features, physicochemical properties and elemental analysis of the leaves. The leaves are pinnate opposite arranged, oblique lamina, glabrous appearance, elliptical in shape, entire margin with reticulate venation. The microscopy revealed straight polygonal wall of epidermal cells, paracytic stomata, unicellular trichomes, xylem, phloem, prismatic & druse crystals, and starch grains. Chemomicroscopy revealed presence of cellulose, cutin, lignin, tannins, starch, calcium oxalate crystals and gum & mucilage. The physicochemical parameters for the leaves estimated include moisture contents (13.11%), total ash value (5.67%), water soluble ash (1.33%), acid insoluble ash (2.00%), water extractive values (13.33%) and alcohol extractive values (10.67%). Elemental analysis revealed the presence of iron, copper, manganese, zinc, nickel, and lead. The pharmacognostic standard observed in this study will be of help in correct identification and quality control of F. andersonii.

Molecular Mechanisms of Plant Trichome Development.

Plant trichomes, protrusions formed from specialized aboveground epidermal cells, provide protection against various biotic and abiotic stresses. Trichomes can be unicellular, bicellular or multicellular, with multiple branches or no branches at all. Unicellular trichomes are generally not secretory, whereas multicellular trichomes include both secretory and non-secretory hairs. The secretory trichomes release secondary metabolites such as artemisinin, which is valuable as an antimalarial agent. Cotton trichomes, also known as cotton fibers, are an important natural product for the textile industry. In recent years, much progress has been made in unraveling the molecular mechanisms of trichome formation in Arabidopsis thaliana, Gossypium hirsutum, Oryza sativa, Cucumis sativus, Solanum lycopersicum, Nicotiana tabacum, and Artemisia annua. Here, we review current knowledge of the molecular mechanisms underlying fate determination and initiation, elongation, and maturation of unicellular, bicellular and multicellular trichomes in several representative plants. We emphasize the regulatory roles of plant hormones, transcription factors, the cell cycle and epigenetic modifications in different stages of trichome development. Finally, we identify the obstacles and key points for future research on plant trichome development, and speculated the development relationship between the salt glands of halophytes and the trichomes of non-halophytes, which provides a reference for future studying the development of plant epidermal cells.

DNA bar-coding, pharmacognostical, and phytochemical analysis of Atalantia monophylla DC. leaves

BACKGROUND: Leaves of Atalantia monophylla DC. (Syn. Limonia monophylla L.), family Rutaceae, are traditionally used to treat rheumatoid pain, hemiplegia, itch and cutaneous complaints, cough, and as an antidote to snake bite, etc. The present study reports the detailed morphology, anatomy, genetic barcoding, physiochemical, and phytochemical aspects of A. monophylla leaves. METHODS: The sample of leaves of the plant were collected from one of its natural habitat, Athagarh forest, Odisha, India. The detailed macroscopic observations were made with naked eyes, and microscopy characters of leaf, stomatal index, and powder microscopy were done as per standard protocol. Physicochemical and qualitative preliminary phytochemical analysis, high-performance thin layer chromatography (HPTLC), and DNA bar-coding studies were carried out as per Ayurvedic Pharmacopoeia of India methods and other standard guidelines. RESULTS: Leaves were opposite, unifoliate, ovate-elliptic, entire, emarginate, and glabrous. Transverse section (TS) through petiole showed epidermis, cortex, pericyclic fibers, and vascular bundles along with trichome. TS of lamina passing through midrib shows lamina with upper and lower epidermis, lignified elements, interrupted by stomata and unicellular trichome. Microscopic characteristics of the leaves powder show the presence of oil globule, rhomboidal crystal, prismatic crystal, and fragment of paracytic stomata. The result of loss on drying, total ash, acid-insoluble ash, water, methanol-soluble extractive, and the obtained pH values were about 10.47 ± 0.40%, 6.94 ± 0.95%, 1.00 ± 0.00%, 30.41 ± 2.26%, 7.64 ± 0.56%, and 6.6, respectively. Qualitative phytochemical analysis shows the presence of carbohydrates, glycosides, saponins, alkaloids, tannins, and flavonoids and the HPTLC study revealed 29 spots at both short (254 nm) and long (366 nm) ultraviolet rays. CONCLUSION: Epidermal cells, oil globule, rhomboidal crystal, prismatic crystal, paracytic stomata, and simple unicellular trichome are key characters for identification of its leaves. The results obtained from pharmacognostical, phytochemical, physicochemical, and DNA bar-coding studies may serve as the diagnostic tool of A. monophylla toward its authentication and identification and also in maintaining of quality, strength, purity, and efficacy of the leaves.

Transcriptomic and functional analysis provides molecular insights into multicellular trichome development.

Trichomes, the hair-like structures located on aerial parts of most vascular plants, are associated with a wide array of biological processes and affect the economic value of certain species. The processes involved in unicellular trichome formation have been well-studied in Arabidopsis (Arabidopsis thaliana). However, our understanding of the morphological changes and the underlying molecular processes involved in multicellular trichome development is limited. Here, we studied the dynamic developmental processes involved in glandular and nonglandular multicellular trichome formation in cucumber (Cucumis sativus L.) and divided these processes into five sequential stages. To gain insights into the underlying mechanisms of multicellular trichome formation, we performed a time-course transcriptome analysis using RNA-sequencing analysis. A total of 711 multicellular trichome-related genes were screened and a model for multicellular trichome formation was developed. The transcriptome and co-expression datasets were validated by reverse transcription-quantitative PCR and in situ hybridization. In addition, virus-induced gene silencing analysis revealed that CsHOMEOBOX3 (CsHOX3) and CsbHLH1 are involved in nonglandular trichome elongation and glandular trichome formation, respectively, which corresponds with the transcriptome data. This study presents a transcriptome atlas that provides insights into the molecular processes involved in multicellular trichome formation in cucumber and can be an important resource for future functional studies.

Taxonomic and Pharmacognostic Evaluation of Leaf of Mussaenda philippica. (Rubiaceae)

Mussaenda philippica Linn. (Rubiaceae) a very important medicinal plant in the treatment of appendicitis and hepatitis as the locals use the species with the white flower. The objective of the study determines various taxonomic and pharmacognostic standards helpful to ensure the identity, purity, safety and efficacy of the medicinal plant, M. phillipica. The leaves were collected, identified, air dried and pulverized. Standard procedures were carried out to obtain microscopic features of the fresh and powdered samples, micromeritic, chemomicroscopy, flourescence properties, soluble extractive values, moisture contents and ash values. The results of the microscopy study of the fresh leaf revealed hypostomatic distribution of stomata with paracytic stomata on the abaxial surface of the leaf only, stomatal number of 56.8, stomatal index of 25.06%, and epidermal number of 169.8, while the adaxial surface had an epidermal number of 241.9. The plant sample of the leaf also possessed unicellular trichomes. Micromeritic properties of the powdered leaf samples showed bulk volume of 35.33±0.33, tapped volume of 28.00±0.00, bulk density of 0.28±0.00, tapped density of 0.35±0.00, angle of repose of 35.4°, Carr’s Index of 20.90±0.74, Hausner’s ratio of 1.26±0.01. Chemomicroscopy study on the leaf powder revealed the presence of lignin, starch, cellulose, calcium oxalate crystals, oil, mucilage and protein. The moisture content was 11 %w/w. Results for the total ash, acid-insoluble ash and water-soluble ash values were 9 %w/w, 1%w/w and 5 %w/w respectively. Results for the ethanol-soluble, methanol-soluble and water-soluble extractive values were 18%w/w, 17 %w/w and 25 %w/w respectively. The above results could be used to establish pharmacopoeial standard of fresh and powdered drug of M. philippica.

Hairiness Gene Regulated Multicellular, Non-Glandular Trichome Formation in Pepper Species.

Trichomes are unicellular or multicellular epidermal structures that play a defensive role against environmental stresses. Although unicellular trichomes have been extensively studied as a mechanistic model, the genes involved in multicellular trichome formation are not well understood. In this study, we first classified the trichome morphology structures in Capsicum species using 280 diverse peppers. We cloned a key gene (Hairiness) on chromosome 10, which mainly controlled the formation of multicellular non-glandular trichomes (types II, III, and V). Hairiness encodes a Cys2-His2 zinc-finger protein, and virus-induced gene silencing of the gene resulted in a hairless phenotype. Differential expression of Hairiness between the hairiness and hairless lines was due to variations in promoter sequences. Transgenic experiments verified the hypothesis that the promoter of Hairiness in the hairless line had extremely low activity causing a hairless phenotype. Hair controlled the formation of type I glandular trichomes in tomatoes, which was due to nucleotide differences. Taken together, our findings suggest that the regulation of multicellular trichome formation might have similar pathways, but the gene could perform slightly different functions in crops.

Comparative Pharmacognostic screening of Tribulus terrestris L. and Tribulus lanuginosus L.

The genus Tribulusbelongs to the family Zygophyllaceae comprises approximately 25 species that grow as prostrate. This study will collect Tribulus terrestris L. and Tribulus lanuginosus L. and analyse their macroscopic, microscopic and phytochemical properties. Selected plant species were collected from three geographical locations in Maharashtra State, India.To confirm the quality and authenticity of plants, standard pharmacognostic procedures described in standard reference books were used to conduct a comparative analysis of Tribulussps. The current study examines pharmacognostic studies on its numerous parts, such as the stem, leaf, flower and fruit.The Study showsT. terretris L., leaf sections demonstrate the presence of unicellular trichomes that are substantially denser in T. lanuginosus L. In numerous tests for qualitative analysis of distinct Tribulussps.phytochemical substances such as alkaloids, starch, carbohydrates, tannin, saponins, glycosides, phenol, flavonoids, and proteins were found to be present.

A SNP Mutation in Homeodomain-DDT (HD-DDT) Transcription Factor Results in Multiple Trichomes (mt) in Cucumber (Cucumis sativus L.).

Trichome is a natural physical barrier protecting plants against environmental stresses, natural infestations, ultraviolet rays and pathogenicity. Trichome also helps plants in maintaining appropriate water content by reducing transpiration rate. The molecular mechanism regulating unicellular trichome development in Arabidopsis has been extensively elucidated, but the molecular mechanism regulating multicellular trichome development remains unclear. In this study, we identified a multiple trichomes (mt) mutant from a cucumber EMS (Ethylmethylsulfone) mutagenesis population. Genetic analysis indicated that an incomplete dominant gene controls the mt trait. Using a combination of map-based cloning and BSA-seq (Bulked Segregant Analysis -Sequencing), we identified the candidate gene, CsaV3_6G050410, responsible for the mt mutation. Sequence alignment revealed one base substitution in gene CsaV3_6G050410, resulting in an amino acid substitution. The deduced amino acid sequence of CsaV3_6G050410 encodes a HD-DDT (homeodomain-DDT) transcriptional regulatory protein containing a conserved homeobox domain and a DDT domain. Gene expression analysis revealed that the expression level of CsaV3_6G050410 in the mt mutant was similar to that in the WT (wild type). Transcriptome analysis indicated that the mt gene may regulate the development of the epidermis by influencing plant hormone signaling pathways or participating in several transcription factor pathways. The results of this study are fundamental for a better understanding of the function of the HD-DDT transcription factor in the trichome development of cucumber.

Physical, Chemical and Biological Study of Leaf Extracts from Senna obtusifolia: Bibliographic Review

Senna obtusifolia (Fabaceae; Synonyms: Cassia obtusifolia, Cassia humilis) is a plant widely found in the state of Amapá, popularly known as “Mata-pasto”, it is widely used worldwide, being used in local and traditional medicine, for diseases related to rheumatism, headache, hepatitis and diuretic. The research was carried out using the databases of theses, dissertations and indexed articles. Additional information was collected from books, reviews and related documents. The morphometric study of the leaves of S. obtusifolia was found in the literature. The analyzes revealed different morphological and anatomical patterns, which are important on the adaxial and abaxial surfaces, since the surface is glabrous and has calcium oxalate druses, unicellular trichomes, epidermal idioblasts. The study of morphology is important in the medicinal activity of the plant since the secondary metabolites in plants are affected by different biotic and abiotic stresses. Thus, stress conditions affect secondary metabolites or the so-called active ingredients and other compounds that plants produce, which are generally the basis of their medicinal activity. According to the literature, several classes of secondary metabolites were found, such as anthraquinones, flavonoids, terpenoids and others in the leaves of S. obtusifolia. Current evidence indicates that the secondary metabolites it contains in extracts of S. obtusifolia have hypocholesterolemic, antioxidant, allelopathic, antinociceptive, anti-inflammatory, cancer-preventing, arthritis, diabetes, heart disease, kidney and liver toxicity, and urinary tract infections. Detailed information in the literature on S. obtusifolia reveals that this species has a wide pharmacological use proven in scientific research.

A discussion of the relationship between Ophiorrhiza exigua and O. michelloides (Rubiaceae) with the description of a new species

Through field observations, studies of herbarium specimens and relevant literature, Ophiorrhiza exigua and O. michelloides, two long‐controversial species are shown to be two different species. Meanwhile, our results supported O. nanlingensis L. Wu & Q. R. Liu as a new species, previously confused with O. exigua. Ophiorrhiza nanlingensis is morphologically similar to O. exigua and O. michelloides, but differs from the former in its monostylous flowers and corolla tube without a ring of hairs inside, and from the latter in pubescence of most vegetative organs with unicellular trichomes which are generally shorter than 0.3 mm and inflorescence nutant when young and then erect. We provide a detailed morphological and habitat description, as well as colour photographs and illustrations of the new species.

Fruits of meadowsweet [<i>Filipendula ulmaria</i> (L.) Maxim.] and dropwort (<i>Filipendula hexapetala</i> Gilib.): comparative morphogical and anatomical investigation

BACKGROUND: Meadowsweet [Filipendula ulmaria (L.) Maxim.], is the representative of flora of the European parts of Russia. It is widespread in Samara Region. The flowers of the meadowsweet are the pharmacopoeial type of raw materials, but the fruits of this plant are not used in medicine. The fruits of the meadowsweet and its closely related type of the dropwort are the promising source of biologically active compounds of phenolic and sterol nature. Introduction of new types of medical plant raw materials into official medical practice requires the development of regulatory documentation, including morphological and anatomical diagnostics of types.
 AIM: The purpose of this work was to study and compare morphological and anatomical features of the structure of meadowsweet fruits and dropwort.
 MATERIALS AND METHODS: The material of the study was the dry fruits of the meadowsweet and dropwort, collected in June-July 2019 in Samara Region. The research was carried out by means of light microscopy in transmitted and reflected light in a light field.
 RESULTS: Morphological and anatomical characteristics of the fruits of two types of meadowsweet were revealed. They hadnt been described in the literature before. So the fruits of the meadowsweet have the following diagnostic features: the stele of the pedicels is of transitional type, lysigenic receptacles located in them are uneven, pubescence of the epidermis occurs due to simple unicellular trichomes; they also have the three-layer structure of the pericarp, a significant quantity of single crystals in the parenchyma of the parmelia, the cone-shaped form of the conducting bundle in the parmelia seam. The fruits of the dropwort are characterised by retort-shaped hairs that make up the thick pubescence of the multiple fruits, peculiar conducting system of the parmelia in the form of one large collateral bundle of the cone-shaped form, located on the side of the seam.
 CONCLUSIONS: The obtained results allow to develop the chapter Microscopic signs as a part of the pharmacopoeial monograph devoted to a new perspective medicinal plant raw materials of Fruits of the meadowsweet and Fruits of the dropwort.

PRELIMINARY PHARMACOGNOSTICAL, PHYTOCHEMICAL STUDY AND HPTLC ANALYSIS OF COSTUS PICTUS D.DON.

The ancient wisdom in Ayurveda medicine is still not exhaustively explored. Multiple exotic plants existent in India which are not described in classical literature of Ayurveda are commonly referred to as Anukta Dravya (undocumented). Costus pictus D.Don is such a plant, recently introduced in India from Mexico, which is used for renal disorders there. In India, it is used in Diabetes mellitus. This is proven for antidiabetic, antioxidant, anticancerous, antimicrobial and diuretic actions. It is an easily propagated, palatable and cost effective plant. Identification through pharmacognostical and phytochemical studies is essential for the standardization of any plant. The green leaf is narrowly elliptic with 10 to 25cm length and 2.5 to 6cm width. Microscopy revealed presence of vascular bundles, unicellular trichomes in upper epidermis, thin walled parenchyma cells in ground tissue and layers of parenchymatous hypodermis. Powder microscopy showed presence of epidermal parenchyma cells with underlying chlorenchyma group of fibers and fibro vascular bundles.TLC photo documentation revealed presence of many phytoconstituents with different Rf values. Densitometric scan showed many peaks, 10 at 254nm, 11 at 366nm, 6 at 520nm and 9 at 620 nm after derivatisation. Moisture content was 20%. The percentage of total ash, acid insoluble ash, and water insoluble ash was determined. The water soluble extractive value was 22.57 which is highest among all the extracts. The results indicated the presence of alkaloid, steroids, tannins, flavanoids, phenol, carbohydrate and resin in ethanolic extract and steroid, flavanoids, phenols, saponins, tannins and glycosides in water extract.

Study of micro-trichome (mict) reveals novel connections between transcriptional regulation of multicellular trichome development and specific metabolism in cucumber

Trichomes that cover the epidermis of aerial plant organs play multiple roles in plant protection. Compared with a unicellular trichome in model plants, the development mechanism of the multicellular trichome is largely unclear. Notably, variations in trichome development are often accompanied by defects in the biosynthesis of cuticle and secondary metabolites; however, major questions about the interactions between developmental differences in trichomes and defects in metabolic pathways remain unanswered. Here, we characterized the glabrous mutant mict/csgl1/cstbh via combined metabolomic and transcriptomic analyses to extend our limited knowledge regarding multicellular trichome development and metabolism in cucumber. Mict was found to be explicitly expressed within trichome cells. Transcriptomic analysis indicated that genes involved in flavonoid and cuticle metabolism are significantly downregulated in mict mutants. Further metabolomic analysis confirmed that flavonoids, lipids, and cuticle compositions are dramatically altered in mict mutants. Additional studies revealed that Mict regulates flavonoid, lipid, and cuticle biosynthesis by likely directly binding to downstream functional genes, such as CsTT4, CsFLS1, CsCER26, and CsMYB36. These findings suggest that specific metabolic pathways (e.g., flavonoids and cuticle components) are co-regulated by Mict and provide insights into transcriptional regulation mechanisms of multicellular trichome development and its specific metabolism in cucumber.

Comprehensive observation of trichome development in Micro-tom tomato

Trichomes help plants defend against various stresses by formation of a protective barrier. Although the unicellular trichomes in <i>Arabidopsis</i> have been well studied, little is known of the development of multicellular trichomes in tomato. With seven morphologically and functionally different types, tomato trichomes are more complex than the unicellular trichomes in <i>Arabidopsis</i>. Here, we comprehensively analyzed the spatiotemporal pattern of tomato trichome development. Our observations show that the gradual reduction of type I/IV trichomes during leaf development is accompanied by an increase of other trichome types. We further examined the gland development of type I/IV trichomes by constructing a marker reporter, pSlAT2: GUS-YFP which is specifically expressed in the top cell of the trichomes. Interestingly, we found the multicellular base of trichomes is initiated as early as the two-cell stage. Through tracking a nuclear marker, H2B-GFP in tomato trichomes, we found the correlation between stalk cell length and nuclear size, suggesting that cell ploidy level could affect trichome cell size. Finally, we found type VII glandular trichomes exhibit two morphologically distinct forms, with the majority covered by a wax-like substance, which could help to form extra storage space for secretory metabolites. Our results provide the basis for further mechanistic study of trichome development in tomato.

Research progress in regulation model in different types of plant trichome

Plant trichomes are special structures that originate from epidermal outgrowths. Trichomes play an important role in plant defense against pests and diseases, and possess economic and medicinal values. Study on molecular mechanism of plant trichomes will contribute to the molecular design breeding and genetic improvement of crops. In recent years, the regulation mechanism of trichome development has been basically clarified in the model plant Arabidopsis thaliana, while great progresses are also found in other plant species. In this review, we focus on the developmental regulation of trichome formation from gene and phytohormones levels in Arabidopsis and cotton (with unicellular trichomes), as well as in tomato and Artemisia annua (with multicellular trichomes). The research progress associated with trichomes is also introduced in other typical monocotyledons and dicotyledons. Finally, the research and application of plant trichomes are prospected.