Autochthonous nutrient recycling driven by soil microbiota could be sustaining high coconut productivity in Lakshadweep Islands sans external fertilizer application.

The soils of Lakshadweep Islands are formed as a result of the fragmentation of coral limestone, that is carbonate-rich, with neutral pH, but poor in plant nutrients. Coconut palm (Cocos nucifera L.) is the main crop cultivated, supporting the life and livelihood of the islanders. No external fertilizer application or major plant protection measures are adopted for their cultivation as the Islands were declared to go organic decades back. Yet, Lakshadweep has one of the highest productivity of coconut compared with other coconut growing areas in India. Therefore, a question arises: how is such a high coconut productivity sustained? We try to answer by estimating in three main islands (i) the nutrients added to the soil via the litter generated by coconut palms and (ii) the role of soil microbiota, including arbuscular mycorrhizae, for the high productivity. Our results indicated that, besides adding a substantial quantum of organic carbon, twice the needed amount of nitrogen, extra 20% phosphorus to the already P-rich soils, 43-45% of potassium required by palms could be easily met by the total coconut biomass residues returned to the soil. Principal Component Analysis showed that soil organic carbon %, potassium, and organic carbon added via the palm litter and AM spore load scored >± 0.95 in PC1, whereas, available K in the soil, bacteria, actinomycetes, phosphate solubilizers and fluorescent pseudomonads scored above >± 0.95 in PC2. Based on our analysis, we suggest that the autochthonous nutrients added via the coconut biomass residues, recycled by the soil microbial communities, could be one of the main reasons for sustaining a high productivity of the coconut palms in Lakshadweep Islands, in the absence of any external fertilizer application, mimicking a semi-closed-loop forest ecosystem.

Automation of route identification and optimisation based on data-mining and chemical intuition.

Data-mining of Reaxys and network analysis of the combined literature and in-house reactions set were used to generate multiple possible reaction routes to convert a bio-waste feedstock, limonene, into a pharmaceutical API, paracetamol. The network analysis of data provides a rich knowledge-base for generation of the initial reaction screening and development programme. Based on the literature and the in-house data, an overall flowsheet for the conversion of limonene to paracetamol was proposed. Each individual reaction-separation step in the sequence was simulated as a combination of the continuous flow and batch steps. The linear model generation methodology allowed us to identify the reaction steps requiring further chemical optimisation. The generated model can be used for global optimisation and generation of environmental and other performance indicators, such as cost indicators. However, the identified further challenge is to automate model generation to evolve optimal multi-step chemical routes and optimal process configurations.

Increasing urinary cotinine concentrations at elevated temperatures: the role of conjugated metabolites.

The presence of cotinine, a nicotine metabolite, in urine above a specified cutoff concentration is commonly used to distinguish smokers from nonsmokers, as in smoking cessation studies. A stability study of cotinine in urine was carried out after questions arose concerning analyte stability at elevated storage and shipment temperatures. Aliquots from a smokers urine pool were stored at 5, 25, 40, 50 and 60 degrees C for 30 days. Another set of aliquots, obtained by diluting the smokers pool 1:1 with nonsmokers urine, were stored under the same conditions. Free cotinine levels, determined by a stability-indicating gas chromatographic/mass spectrometric (GC/MS) assay, increased over the 30-day period at higher storage temperatures. Cotinine concentrations in the aliquots stored at 60 degrees C, for example, nearly doubled over 30 days (1301 to 2476 ng/ml), with similar proportional increases observed in the aliquots diluted with nonsmokers urine. Since cotinine can be excreted to a large degree as cotinine-N-glucuronide, this conjugated metabolite was determined by an indirect method. As the storage temperature increased, the free/conjugated cotinine ratio dramatically increased, pointing to cotinine-N-glucuronide as the source of the additional free cotinine at the higher storage temperatures. The results of this study are of much practical importance, since urine samples with free cotinine concentrations just below a cutoff value may become positive for smoking status if suitably low temperatures cannot be maintained during sample handling and shipment.

The effect of butyrate on the healing of colonic anastomoses in rats.

BACKGROUND: Butyrate, a short-chain fatty acid (SCFA) formed by the fermentation of complex carbohydrates by the bacteria in the colon, is the main source of nutrition for colonocytes. The aim of this experiment was to investigate the effect of butyrate on the healing of colonic anastomosis in a rat model. MATERIALS AND METHODS: Forty male Wistar rats were fed a fibre-free diet for 2 days. They then underwent laparotomy, transection, and anastomosis of both left and right colon, with a defunctioning caecostomy. The animals were then randomly assigned to receive butyrate or saline enemas from the third postoperative day and underwent another laparotomy on the seventh postoperative day when the bursting pressures of both anastomoses were measured. RESULTS: Out of the 40 rats, 23 were available for the final data analysis. The mechanical strength of the anastomosis was measured by the bursting wall tension (BWT), which was calculated from the bursting pressure and the anastomotic circumference. The anastomoses in the butyrate arm showed a significantly higher BWT for both the right (48.9 s 64.71 dyne10(-3)/cm, p value .04) and the left (51.44 vs 72.38 dyne 10(-3)/cm, p value .01). CONCLUSION: This experiment suggests that butyrate has a significant role in increasing the mechanical strength of colonic anastomoses in rats.