Synthesis, characterization, and cytotoxicity studies of nanocellulose extracted from okra (Abelmoschus Esculentus) fiber.

Nanocellulose, especially originating from a natural source, has already shown immense potential to be considered in various fields, namely packaging, papermaking, composites, biomedical engineering, flame retardant, and thermal insulating materials, etc. due to its environmental friendliness and novel functionalities. Thus, a thorough characterization of nanocellulose is a hot research topic of research communities in a view to judge its suitability to be used in a specific area. In this work, a kind of green and environment-friendly nanocellulose was successfully prepared from okra fiber through a series of multi-step chemical treatments, specifically, scouring, alkali treatment, sodium chlorite bleaching, and sulfuric acid hydrolysis. Several characterization techniques were adopted to understand the morphology, structure, thermal behavior, crystallinity, and toxicological effects of prepared nanocellulose. Obtained data revealed the formation of rod-shaped nanocellulose and compared to raw okra fiber, their size distributions were significantly smaller. X-ray diffraction (XRD) patterns displayed that compared to the crystalline region, the amorphous region in raw fiber is notably larger, and in obtained nanocellulose, the crystallinity index increased significantly. Moreover, variations in the Fourier transform infrared spectroscopy (FTIR) peaks depicted the successful removal of amorphous regions, namely, lignin and hemicelluloses from the surface of fiber. Thermostability of synthesized nanocellulose was confirmed by both Differential Scanning Calorimetry (DSC) analysis, and thermogravimetric analysis (TGA). Cytotoxicity assessment showed that the okra fiber-derived nanocellulose exhibited lower to moderate cellular toxicity in a dose-dependent manner where the LD50 value was 60.60 µg/ml.

Investigation of the performance of okra fiber in woven fabric.

There has been an increase interest in natural plant fibers over the last decades with the intension to identify the ecologically acceptable alternatives to reduce the dependency on synthetic fibers. Naturally extracted okra fiber (Abelmoschus esculentus) was used in this study. Since okra is a stiff fiber, yarns with 100% Okra fiber was not possible to produce and tried to blend with polyester. The maximal ratio of okra was 20% with polyester to spin yarns in traditional ring spinning system. This study explores, for the first time, the possibility of manufacturing woven fabric with polyester-okra (80/20) yarns at weft direction with 100% cotton yarn at warp direction in order to prominent blend effect at weft direction. The properties of produced fabrics were compared with the same produced widely-used polyester-linen (PL) (80/20) counterpart. The both PO and PL woven fabrics were characterized in terms of fabric weight, thickness, abrasion, pilling, fuzzing, air permeability, tensile strength and tear strength. In addition, the morphological aspects of the fiber alignment in the woven fabric structure were observed using optical microscopic images. The performance of PO woven fabric was in acceptable ranges and can be considered as a sustainable blended woven fabric to meet the actual demand in the textile weaving industries.