Recent advances of natural fibers based green rubber composites: Properties,current status,and future perspectives

The searching of suitable alternatives to petroleum-based fillers is an uncompromising challenge in present day rubber research. Recently, natural fibers are the part of great attention of both academic and industrial researchers due to their easy availability, environmental friendliness, and biodegradability. Natural fiber is cellulose-rich material, which is preferentially used as alternative filler in rubber technology. This article reviews current advances in natural fibers filled rubber composites in terms of mechanical, thermal, and biodegradable properties (2010–2020). The incorporation of unmodified natural fibers as filler is not able to offer desired reinforcement in rubber composites. Several surface modification methods can be introduced to improve the overall performances of natural fibers filled rubber composites. Finally, the review clarifies present status and future prospects of natural fibers based advanced rubber composites in automobile industry. The successful designing of natural fibers based sustainable rubber composites can introduce a new era in green rubber technology.     

Antimicrobial gallic acid from Caesalpinia mimosoides Lamk.

Different extracts of Caesalpinia mimosoides Lamk. (Leguminosae) were tested against eight human pathogenic bacteria and six fungal strains by the disc diffusion method. Among these extracts, the aqueous and the ethanolic extracts showed potent activity against some tested microorganisms. Subsequently, the latter extract was fractionated by means of Sephadex LH-20 column chromatography. A bioactive substance, responsible for the antimicrobial property was separated, and its structure was assigned as a known compound, gallic acid, by extensive chromatographic and spectroscopic analyses.