No abstract

PurposeThe paper aims to investigate the feasibility of developing natural dyes from the barks of Araucaria columnaris and leaves of Macaranga peltata, Averrhoa bilimbi. The paper also deals with the application of natural dyes in textile coloration.Design/methodology/approachDye extraction was carried out using the aqueous method. The dyeability of the aqueous extract was assessed on cotton, silk and polyester yarns using different mordants (alum, acetic acid, CuSO4, lemon juice) and without mordant. UV–Visible spectral analysis and pH of different natural dyes were determined. Percent absorption, K/S values, CIELab values and fastness properties of the selected dyed yarns were also assessed.FindingsThe percentage values for dye exhaustion differed with various mordants. The K/S values were found to be influenced by the addition of mordants. Different hues were obtained with the usage of different mordants. Fastness results exhibited good to very good grades.Research limitations/implicationsThe effective application of aqueous method of dye extraction in the study avoids solvent toxicity. The current results proved that the dyeing could be achieved at room temperature for different yarns (cotton, silk, polyester). At present, no report exists in the literature of research work on the extraction of natural dyes from the leaves of M. peltata, A. bilimbi and their dyeing potential on cotton, silk and polyester.Practical implicationsThe present work offers new environment-friendly dye as well as simple dyeing method. Barks and leaves are promising sources of dye. Enormous availability of barks and leaves avoids the exploitation of the plant parts for the extraction of natural dyes.Originality/valueThe important feature of this study was the effective dyeing of natural and synthetic fibers at room temperature. The novel sources of natural dyes would contribute significantly to the existing knowledge of dyeing, and the natural dyes reduce the environmental impact of synthetic dyes.

No abstract

Objective: Aristolochia krisagathra, a species endemic to the Western Ghats of India is found closely allied to two other species native to India, A. indica and A. tagala. The plant is medicinally useful and hence may harbor important phytochemical constituents. The phytochemical studies on this plant are less. Hence, the objective of the research was to analyse the oil composition of this endemic plant considering the seasons and plant parts. Methods:The essential oil analyses of both the leaf and stem oil of the plant was carried out in three different periods, pre-monsoon, monsoon and post-monsoon to analyse the major compounds present and the effect of seasons on the oil composition. Oil extraction of the shade dried leaves and stem were done in a clevenger type apparatus. 4 h of hydro distillation was done and the oil samples were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). Results:The stem oil yield was higher than leaves and the oil colour of the leaves and stem varied. The results showed the predominance of sesquiterpenes. Diterpenes were completely absent in the stem oil in all the three seasons but was present in leaf oil in small concentrations. The oil yield from stem was higher than leaves. The major compound in the leaf and stem oil varied. Major compound in the pre-monsoon and postmonsoon remained the same, copaene in the leaf and alloaromadendrene in the stem. The major compound in the monsoon period was deltacadinene in leaf and spathulenol in stem. Caryophyllene, the sesquiterpene hydrocarbon, was present in both the stem and leaf oil irrespective of the seasons studied. Conclusion:The study showed that the plant parts and seasons are important factors affecting the oil composition. Hence while collecting medicinal plants and their oils for various bioactivities, these factors need to be considered.

The finite, depleting and unsustainable nature of fossil fuels remained a global concern. This had continued to stir up an urgent need to consider cheaper renewable and sustainable alternative. Consequently, the assay of proximate and physico-chemical potentials of crude kernel oil extracts of Canarium schweinfurthii Engl. was conducted. This was intended to evaluate the nutritional and some of the inherent biodiesel properties. The procedure according to Association of Official and Analytical Chemist (AOAC) were deployed to analyze the proximate, physico-chemical and fatty acids contents of the crude kernel oil extracted of the test plant. It was found that the oil sample of the test plant had 9.25±0.05% (moisture content), 6.10±0.09% (crude fiber), 23.62±0.02% (crude protein), 44.35 ±0.04% (crude lipid), 10.35±0.04% (ash) and 6.33±0.03% (carbohydrate). The physico – chemical assay of the oil revealed promising biodiesel properties with relative density (0.966±0.01g/cm3), refractive index (1.465±0.05 at 30°C), calorific value (38.93±0.13MJ/kg), viscosity value (150.1±0.70 mm2/s), saponification value (220.30±0.98 mgKOH/g), peroxide value (4.26 ± 0.08meq/Kg), acid value (2.49±0.04 mgKOH/g), iodine value (64.70±0.10 g/100g) and cetane number (56.52±0.68). Furthermore, 14-methyl Pentadecanoic acid, methyl ester (C17H34O2), 13,16-Octadecanoic acid, methyl ester (C19H34O2) and Heptacosanoic acid, methyl ester (C28H56O2) were the assayed fatty acids content of crude kernel oil extract of C. schweinfurthii. These had relative percentage abundance (RPA) of 25.80±0.04%, 67.60±0.30% and 6.60±0.03%. The findings clearly elucidated the biodiesel potential of the kernel oil sample of C. schweinfurthii and consequently recommended its incorporation. In this regard, it became imperative for concerted afforestation efforts that would guarantee its sustainable utilization.