Composition and structural characterization of pectin in micropropagated and conventional plants of Premma puberula Pamp.

The metabolites produced by plants can be enhanced by plant tissue culture. In Premma puberula Pamp., the pectin content in leaves is 30 %-40 %, and it is widely used in the food industry and medicine. However, inefficient propagation has seriously restricted the utilization of pectin resources. Therefore, we established an efficient micropropagation technology for P. puberula through comparative analysis in mature leaves of regenerated and conventionally propagated plants. The results showed that the pectin composition of their leaves was similar in terms of galacturonic acid, monosaccharide composition, degree of esterification, functional groups, nuclear magnetic resonance spectrum and morphological characteristics. Furthermore, micropropagated plants had better hardness, gumminess and chewiness characteristics than conventionally propagated plants and were similar in emulsion stability, adhesiveness, springiness, cohesiveness and viscoelasticity. Therefore, micropropagation technology will provide an important guarantee for the industrial production of pectin from P. puberula. The technical essentials include callus induction, embryoid formation, and root induction, followed by acclimatization and transplanting.

Biofertilization with Azospirillum brasilense improves in vitro culture of Handroanthus ochraceus, a forestry, ornamental and medicinal plant.

Biofertilization with plant growth-promoting rhizobacteria is a potential alternative to plant productivity. Here, in vitro propagation of Handroanthus ochraceus (yellow lapacho), a forest crop with high economic and environmental value, was developed using the Azospirillum brasilense strains Cd and Az39 during rhizogenesis. Epicotiles of in vitro plantlets were multiplied in Woody Plant Medium (WPM). For rooting, elongated shoots were transferred to auxin-free Murashige-Skoog medium with Gamborg's vitamins and WPM, both at half salt concentration (½MSG and ½WPM), and inoculated with Cd or Az39 at the base of each shoot. Anatomical studies were performed using leaves cleared and stained with safranin for optical microscopy and leaves and roots metalized with gold-palladium for scanning electron microscopy (SEM). In ½WPM auxin-free medium, A. brasilense Cd inoculation produced 55% of rooting, increased root fresh and dry weight (45% and 77%, respectively), and led to lower stomata size and density with similar proportion of open and closed stomata. Both strains selectively increased the size or density of glandular trichomes in ½MSG. Moreover, bacteria were detected on the root surface by SEM. In conclusion, the difference in H. ochraceus response to A. brasilense inoculation depends on the strain and the plant culture media. Cd strain enhanced rooting in auxin-free ½WPM and produced plantlets with features similar to those expected in ex vitro plants. This work presents an innovative in vitro approach using beneficial plant-microorganism interaction as an ecologically compatible strategy in plant biotechnology.

[Anatomical structures of Coleus forskohlii transplanted in Tongcheng].

OBJECTIVE: To investigate the vegetative tissues of Coleus forskohlii cultivated in Tongcheng, Hubei Province, and to provide useful information for its planting. METHODS: The root, stem, leaf and enlarged rhizome of Coleus forskohlii were subject to routine paraffin section and staining with safranin and fast green FCF solution before examination by light microscopy. RESULTS: The secondary tissue was well developed in root, and stem showed a higher percentage of cortex and pitch, and 4 large vascular bundles. Leaf epidermis was covered by lots of trichomes, including glandular hairs, glandular scale and linear non-glandular hairs. Mesophyll tissue was poorly differentiated to palisade and spongy tissues. Enlarged rhizome was the same as normal dicotyledons plants. CONCLUSION: Enlarged rhizome, unconspicuous root tuber and poorly differentiated leaf mesophyll cells are 3 main different features of Coleus forskohlii transplanted in Tongcheng. These results provide scientific basis for formulating quality standards, further cultivation and utilization of the plant.

Development and structure of internal glands and external glandular trichomes in Pogostemon cablin.

Pogostemon cablin possesses two morphologically and ontogenetically different types of glandular trichomes, one type of bristle hair on the surfaces of leaves and stems and one type of internal gland inside the leaves and stems. The internal gland originates from elementary meristem and is associated with the biosynthesis of oils present inside the leaves and stems. However, there is little information on mechanism for the oil biosynthesis and secretion inside the leaves and stems. In this study, we identified three kinds of glandular trichome types and two kinds of internal gland in the Pogostemon cablin. The oil secretions from internal glands of stems and leaves contained lipids, flavones and terpenes. Our results indicated that endoplasmic reticulum and plastids and vacuoles are likely involved in the biosynthesis of oils in the internal glands and the synthesized oils are transported from endoplasmic reticulum to the cell wall via connecting endoplasmic reticulum membranes to the plasma membrane. And the comparative analysis of the development, distribution, histochemistry and ultrastructures of the internal and external glands in Pogostemon cablin leads us to propose that the internal gland may be a novel secretory structure which is different from external glands.

Agrobacterium-mediated genetic transformation of Pogostemon cablin (Blanco) Benth. Using leaf explants: bactericidal effect of leaf extracts and counteracting strategies.

An optimized protocol for Agrobacterium tumefaciens-mediated transformation of patchouli using leaf disk explants is reported. In vitro antibacterial activity of leaf extracts of the plants revealed Agrobacterium sensitivity to the extracts. Fluorometric assay of bacterial cell viability indicated dose-dependent cytotoxic activity of callus extract against Agrobacterium cells. Addition of 0.1% Tween 20 and 2 g/l L-glutamine to Agrobacterium infection medium counteracted the bactericidal effect and significantly increased the T-DNA delivery to explants. A short preculture of explants for 2 days followed by infection with Agrobacterium in medium containing 150 µM of acetosyringone were found essential for efficient T-DNA delivery. Cocultivation for 3 days at 22 °C in conjunction with other optimized factors resulted in maximum T-DNA delivery. The Agrobacterium-mediated transformation of leaf disk explants were found significantly related to physiological age of the explants, age and origin of the of the donor plant. Leaf explants from second node of the 3-month-old in vivo plants showed highest transformation efficiency (94.3%) revealed by transient GUS expression assay. Plants selected on medium containing 20 mg/l kanamycin showed stable GUS expression in leaves and stem. The elongated shoots readily developed roots on kanamycin-free rooting medium and on transfer to soil, plants were successfully established. Polymerase chain reaction (PCR) and reverse-transcriptase PCR analysis in putative plants confirmed their transgenic nature. The established transformation method should provide new opportunities for the genetic improvement of patchouli for desirable trait.

[Studies on characteristics of volatile oil and micro-identification between Herba Pogostemonis and Herba Agastachis rugosae].

OBJECTIVE: To compare the chemical components of Herba Pogostemonis and Herba Agastachis rugosae, and develop a new method for the identification of them. METHODS: Comparing the chemical components in volatile oil of Herba Pogostemonis and Herha Agastachis rugosae by GC-MS, and identifying leaves of them by micro-characteristics. RESULTS: Patchouli alcohol (71.45%), the major component of Herba Pogostemonis, was its characteristic constituent and pulegone (37.58%) was the major component and characteristic constituent of Herba Agastachis rugosae. Two cells formed the head of glandular hairy in Herba Pogostemonis, while only one formed the head of glandular hairy in Herba Agastachis rugosae. The nonglandular hair was mainly constituted by one to three cells in Herba Pogostemonis, while one to four cells constituted the nonglandular hair in Herba Agastachis rugosae. CONCLUSION: A simple and dependable identification method has been developed for Herba Pogostemonis and Herba Agastachis rugosae.

Ethnobotany, biochemistry and pharmacology of Minthostachys (Lamiaceae).

AIMS OF THE STUDY: The South American mint genus Minthostachys is of great importance in the Andes as a medicinal, aromatic, culinary and commercial essential oil plant. After decades of taxonomic confusion and virtual indeterminability of specimens, new systematic and taxonomic work has been conducted in recent years. The present paper attempts to summarize the state of knowledge about Minthostachys with a focus on ethnobotany, analyses of essential oil content and pharmacology, to identify the currently accepted species names for the plants examined in these previous studies, and to assess where additional research is needed. MATERIALS AND METHODS: All available studies on Minthostachys were obtained and evaluated. Herbaria were contacted to identify voucher specimens cited in the respective publications. RESULTS AND CONCLUSIONS: The great majority of published studies was conducted on a single species, Argentinean Minthostachys verticillata. In contrast, the most widely distributed and well-known species (Minthostachys mollis) as well as several locally important and intensively used species (e.g., Minthostachys acutifolia) have received disproportionately little attention, and virtually nothing is known about the local endemics among the 17 species currently recognized. In many cases, however, it is difficult to relate the results to taxonomic entities due to the lack of voucher specimens. Future research efforts should especially be directed at studying the chemistry and potential for use of several common but so far neglected species of the central and northern Andes, at disentangling environmental and genetic influences on essential oil composition, at prerequisites for cultivation, and at the pharmacological basis of the most important traditional uses. Because of the morphological complexity of the genus, future researchers are urged to deposit voucher specimens of the plants used in their studies to facilitate species identification and to make the results more comparable and reproducible.

Sterols and triterpenes in cell culture of Hyssopus officinalis L.

Cell suspension cultures from hypocotyl-derived callus of Hyssopus officinalis were found to produce two sterols i. e. beta-sitosterol (1) and stigmasterol (2), as well as several known pentacyclic triterpenes with an oleanene and ursene skeleton. The triterpenes were identified as oleanolic acid (3), ursolic acid (4), 2alpha,3beta-dihydroxyolean-12-en-28-oic acid (5), 2alpha,3beta-dihydroxyurs-12-en-28-oic acid (6), 2alpha,3beta,24-trihydroxyolean-12-en-28-oic acid (7), and 2alpha,3beta,24-trihydroxyurs-12-en-28-oic acid (8). Compounds 5-8 were isolated as their acetates (6, 8) or bromolactone acetates (5, 7).

[Study on morphological and histological identification of herba pogostemonis].

OBJECTIVE: To identify two types of Pogostemon cablin (Guang Huoxiang), Shipai Huoxiang and Hainan Huoxiang. METHOD: Morphological and microscopical methods. RESULTS: Long bag-like glandular hairs with one-cell head existing in the intercellular space are found in the cortex of stems, mesophyll and parenchyma of midrib. The glandular hairs with special large one-cell head and with a special short and small one-cell stalk, flat bag-like cuticle above secretory cell are caved in the forms of square, triangle, convex len and round-oids are also found in the surface of leaves and stems. The primary pholem fiber bundles with very thick walls are uncontinuous and arranged with a circle in the transverse section of stems; the perimedullary cells contain needle and prism crystals. Above-mentioned characters are differed from other plants of Labiate family. The old stems are cylinderoid forms, branch angles are usually smaller than 60 degrees, the surface of upper, middle stems and young leaves with purple colour are unusual, the palisade ratio are less than 10(5.05 and 9.26 cultivated seperatedly in Guangzhou and Gaoyao), in Shipai Huoxiang. But in Hainan Huoxiang, the old stems are rectangular cylinder, branch angles are usually over 60 degrees, the surface of upper, middle stems and young leaves are commonly purple colour, the palisade ratio are over 10(14.35, 13.18, 13.84 and 14.33 cultivated separatedlly in Wuchuan, Suixi, Leizhou and Hainan). CONCLUSION: Above-mentioned characters may distinguish two types of Pogostemon cablin, Shipai Huoxiang and Hainan Houxiang.

[Identification of herba pogostemonis and its confused species Anisomeles indica].

The article reports the morphological, histological and TLC identification for Herba Pogostemonis and its adulterant, Anisomeles indica, which appears recently. It provides foundation for identificating Herba Pogostemonis.