Mechanical superiority of Pseudoxytenanthera bamboo for sustainable engineering solutions.

The advancement in natural fibre composites has replaced synthetic fibres in various commercial sectors. Bamboo species possess high mechanical properties due to their lignocellulosic fibre content, which makes them suitable for engineering applications and potential alternatives to solid wood. However, despite Bamboo being composed of 130 genera and 1700 different species, out of which many still remains underexplored. In this study, we investigated the, Lignocellulosic profiling, fibre strength, and mechanical characterization of two species of Pseudoxytenanthera Bamboo: Pseudoxytenanthera ritchiei, Pseudopxytenanthera stocksii, and the results obtained were compared with Bambusa balcooa, one of the priority species of bamboo identified by The International Plant Genetic Resources Institute (IPGRI). BET (Brunauer-Emmett-Teller) was used to quantify the samples' density, while SEM-EDX and FTIR spectroscopy were used for elemental analysis. The samples were then subjected to tensile test in addition, thermogravimetric analysis and water absorption test were carried out for the three species. The results showed that Pseudoxytenanthera species possessed superior chemical and mechanical characteristics compared to the priority species of bamboo used for composites. Out of the two Pseudoxytenanthera species studied, Pseudoxytenanthera stocksii exhibited the highest values of cellulose, hemicellulose, lignin, pectin, ash, carbon, and silicon, indicating its chemical superiority. Moreover, Pseudoxytenanthera stocksii also showed higher mechanical values for tensile strength, making it suitable for a variety of engineering applications. The TGA values also indicated that Pseudoxytenanthera stocksii is stable at high temperatures when compared with other natural fibres.

'Sharpshooter' in Botanic Garden: the tale of a rare plant-insect interaction.

Here we report a unique plant-insect interaction between the leafhopper Aloka depressa (tribe Phlogisini) and the host liana, Diploclisia glaucescens, from a Botanic Garden located at the southern edge of Western Ghats in India. Field observations and SEM micrographs were employed to derive evidences on this rare plant-insect interaction. 20-Hydroxyecdysone (20E), insect moulting hormone, was detected and quantified in the host plant D. glaucescens using HPTLC-densitometry. 20E was isolated and characterized from D. glaucescens using column chromatography, 1H-, 13C-NMR and HR-MS. 20E was also detected in A. depressa excrement using HPTLC-densitometry. The leafhopper A. depressa is functioning as a 'sharpshooter' drawing nutrients from the host liana, D. glaucescens, and flinging the waste fluid as droplets through their tail ends. SEM micrographs of A. depressa revealed its external morphological features, characteristic of a sharpshooter. We quantified 20E (0.44-1.44%, dry wt.) in various parts of D. glaucescens. 20E (1.47%, dry wt.) was also detected in the excrement of A. depressa. This plant (D. glaucescens)-insect (A. depressa) association crucially is not damaging the host liana. Considering the diseases caused by sharpshooting leafhoppers in the Americas, this association and the survival of the host plant (D. glaucescens) is illustrating a unique plant-insect interaction.

Carbon dioxide emission from bamboo culms.

Bamboos are one of the fastest growing plants on Earth, and are widely considered to have high ability to capture and sequester atmospheric carbon, and consequently to mitigate climate change. We tested this hypothesis by measuring carbon dioxide (CO2 ) emissions from bamboo culms and comparing them with their biomass sequestration potential. We analysed diurnal effluxes from Bambusa vulgaris culm surface and gas mixtures inside hollow sections of various bamboos using gas chromatography. Corresponding variations in gas pressure inside the bamboo section and culm surface temperature were measured. SEM micrographs of rhizome and bud portions of bamboo culms were also recorded. We found very high CO2 effluxes from culm surface, nodes and buds of bamboos. Positive gas pressure and very high concentrations of CO2 were observed inside hollow sections of bamboos. The CO2 effluxes observed from bamboos were very high compared to their carbon sequestration potential. Our measurements suggest that bamboos are net emitters of CO2 during their lifespan.

Promising anti-diabetes mellitus activity in rats of ß-amyrin palmitate isolated from Hemidesmus indicus roots.

While evaluating the toxicity of the tuberous root extracts of Hemidesmus indicus, a traditional medicinal plant, the glucose lowering property of the root was observed by the investigators. Therefore, it was thought of interest to isolate the anti-hyperglycemic principle from the root and determine its utility to develop an anti-diabetes mellitus medicine. The active principle was isolated from H. indicus root extract by anti-hyperglycemic activity guided chromatographic techniques. Glucose tolerance test in rats was used to evaluate the anti-hyperglycenic property. Anti-diabetes mellitus property was evaluated in alloxan-induced diabetic rats as well as streptozotocin-induced (type-2 model) diabetic rats. The active principle was isolated and identified with spectral data as ß-amyrin palmitate. Although it is a known compound, its presence in H. indicus is not known previously. It was observed for the first time that ß-amyrin palmitate has remarkable anti-hyperglycemic activity in orally glucose loaded rats. Further, interestingly, it exhibited excellent anti-diabetes mellitus activity in both alloxan-diabetic and streptozotocin-diabetic rats at a very low concentration (50µg/kg body weight). One of the mechanisms of action of ß-amyrin palmitate appears to be blocking the entry of glucose from the intestine. ß-Amyrin palmitate is very promising to develop a medicine for diabetes for combination therapy and/or mono-therapy.

Fluorescent prey traps in carnivorous plants.

Carnivorous plants acquire most of their nutrients by capturing ants, insects and other arthropods through their leaf-evolved biological traps. So far, the best-known attractants in carnivorous prey traps are nectar, colour and olfactory cues. Here, fresh prey traps of 14 Nepenthes, five Sarracenia, five Drosera, two Pinguicula species/hybrids, Dionaea muscipula and Utricularia stellaris were scanned at UV 366 nm. Fluorescence emissions of major isolates of fresh Nepenthes khasiana pitcher peristomes were recorded at an excitation wavelength of 366 nm. N. khasiana field pitcher peristomes were masked by its slippery zone extract, and prey capture rates were compared with control pitchers. We found the existence of distinct blue fluorescence emissions at the capture spots of Nepenthes, Sarracenia and Dionaea prey traps at UV 366 nm. These alluring blue emissions gradually developed with the growth of the prey traps and diminished towards their death. On excitation at 366 nm, N. khasiana peristome 3:1 CHCl3­MeOH extract and its two major blue bands showed strong fluorescence emissions at 430­480 nm. Masking of blue emissions on peristomes drastically reduced prey capture in N. khasiana pitchers. We propose these molecular emissions as a critical factor attracting arthropods and other visitors to these carnivorous traps. Drosera, Pinguicula and Utricularia prey traps showed only red chlorophyll emissions at 366 nm.

Chemical composition and antimicrobial activity of essential oil from the rhizomes of Amomum cannicarpum.

The essential oil obtained by hydrodistillation of the rhizomes of Amomum cannicarpum was analyzed by GC and GC/MS. Thirty-four compounds were identified, of which the major components were beta-terpineol (13.4%), beta-pinene (9.4%) and alpha-pinene (6.9%). The essential oil showed significant antimicrobial activity.