Osyris alba is a dioecious shrub used in traditional medicine for its bioactive secondary metabolites. It is used for its antiparasitic, antimicrobial and anti-bleeding properties. In the present study the leaf tissue arrangement, histochemsitry and callus formation of Osyris alba L. were investigated. Leaves (fresh and fixed) were observed by light, polarized oight and electron microscopy. Fresh stem was also observed by light microscopy. The sub-cellular localization of secondary metabolites was detected. Furthermore, in vitro production of its secondary metabolite, by using cell cultures, was also preformed. The compact leaves are amphistomatic, with a single layer of epidermal cells and contain idioblasts cells with crystals. They react positively to histochemical reagents for the major groups of secondary metabolites. In the preliminary histochemical screening, in vitro cultured cells also gave positive results. In conclusion, the medicinal nature of the plant is attributed to its phytochemical profile. Plant cell culture technologies can be used for the production of its bioactive molecules. © 2016, International Journal of Pharmacognosy and Phytochemical Research. All rights reserved.

A series of experiments was carried out to investigate any structural or biochemical alterations on Arabidopsis thaliana (Col.) plants after a long term exposure to non ionizing radiation emitted from the base unit of a cordless DECT system. Exposed plants, compared to their control counterparts, seem to be affected concerning their biomass and leaf structure. Their leaves are thinner and possess fewer chloroplasts. SEM observations of the exposed leaves reveal that the only feature affected is the pubescence which almost disappears while TEM investigation revealed minor structural effects in the chloroplasts. The reduction in the number of chloroplasts as well as the decrease of stroma thylakoids and photosynthetic pigments are probably the main reasons for a weak photosynthetic potential and a consequent reduction of the biomass production. © 2016 Elsevier GmbH.

Kenaf (Hibiscus cannabinus L.) was experimentally cultivated with the use of digested, dried sewage sludge (130 t/ha) and water from a municipal Sewage Treatment Plant (STP) in order to assess their potential to replace conventional fertilization (100 kg N/ha, 75 kg P2O5/ha and 75 kg Κ2O/ha) and irrigation. Tap water and treated wastewater were used for irrigation in quantities corresponding to 6500 m3/ha. Four different treatment combinations were applied as follows: (a) wastewater irrigation and conventional fertilization, (b) wastewater irrigation and sewage sludge fertilization, (c) tap water irrigation and sewage sludge fertilization, and (d) tap water irrigation and conventional fertilization. The dry plant biomass collected in the final harvest (140 days after plant emergence) from the four treatment plots was 12.3 t/ha, 12.6 t/ha, 12.4 t/ha and 12.8 t/ha respectively. These differences were not statistically significant (ANOVA, P = 0.05) and, therefore, it was concluded that the use of municipal wastes had similar effects on dry biomass production with that of conventional fertilization. An earlier harvest (125 days after plant emergence) gave 11.3% lower dry biomass on average in relation to the second harvest, and this difference was statistically significant (ANOVA, P = 0.05). Premature harvest may lead to significant biomass losses, so the plant must be collected during its technological maturity stage. There was not any statistically significant difference among the four treatments and between the two harvests in fiber dimensions and derived values (suitability indices for paper manufacture). On the other hand, cellulose and lignin content in the second harvest were significantly higher compared to the first one, whereas no significant differences were detected among the four treatments. © 2016 Elsevier B.V.

Heavily "armed" with trichomes, the hypostomatic leaf of Ficus carica L. is investigated with light and scanning electron microscopy. Histochemical tests were also applied to trace the secondary matabolites produced in the leaf of this well known, Mediterranean tree with the delicious fruits. Numerous idioblasts with crystals, laticifers and sized lythocysts appear within the compact mesophyll. Protective trichomes are located on both surfaces while capitate secretive hairs and stomata appear only abaxially. Stomata, concerning their magnitude, can be assembled in three size-groups in which the arrangement of their parastomatal cells differs as well. Histochemical reactions proved positive only for alkaloids within the laticifers and phenolic compounds, especially for the condensed tannins accumulated within the vacuole of the epidermal cells of this simply constructed leaf with unique features among the Mediterranean herbs. Comparison of GC-MS and LC-HRMS spectra of different extracts of the nerves and, separately, the rest of the leaf, revealed that coumarines such as umbeliferone, psoralen, bergapten and xanthotoxol are probably biosynthetically produced within the nerve area where the highly differentiated, main secretive apparatus of the leaf (laticifers) resides. That is why, these metabolites, are absent from the extracts of the undifferentiated cells derived from in vitro cultures. © 2015 Elsevier GmbH.