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India is the largest producer of CNSL (estimated at 45,000 mt). Brazil is the largest exporter, with average exports over the years of around 17,000 mt, although within the last few years, this has risen to 35,000 mt per year. Other origins such as Vietnam and Tanzania export volumes that are far behind the two main suppliers, India, and Brazil. In India, most factories use drum roasting but some are now moving to the steam process as it produces a better quality kernel . The Mangalore factories that use steam produce
21.000 mt of India’s 60,000 mt of CNSL, although their proportion of total kernel production is much lower. Karnataka State factories, which process large volumes of kennels, produce about 20,000 mt, and the balance of CNSL production is spread over India’s other cashew producing areas. The export of CNSL from India received a significant boost last year following lobbying by the trade. CNSL was included in an export incentive scheme which allows offsetting import duties against export scrip .
Given that India processes approximately 1.1 million tones of in-shell cashews per year, potential CNSL production is about 160,000 mt, assuming that half the factories use steaming. However, as many of the processing units are small, seasonal, and based on low levels of capital investment, it is highly unlikely that this figure, or anything close to it, will be realized in the medium term. For India’s supply of commercial CNSL to grow, major consolidation of the industry is likely needed, and this would require heavy and widespread capital investment. In addition, rising energy costs reduce the incentive to commercialize CNSL, rather than use it as a fuel. India has a significant secondaiy industry refining CNSL into cardanol and other usable products. Indian exports are approximately 75% CNSL and 25% cardanol .
In Brazil, CNSL is produced by all ten processors. Recovery is about 12% of in-shell weight. This gives overall production for 2009 of 38,400 mt, and for 2010, about 32,000 mt are projected. Production is clearly linked to the size of the cashew crop which has varied from 250,000 mt to 320,000 mt in recent years. Exports of CNSL have once or twice reached as high as
35.000 mt (2005), but in recent years have been just less than 20,000 mt per year. Producers earn more from exporting CNSL, but it also can be sold to the domestic biofuel sector, which is well developed in Brazil . There are no signs of difficulty in commercializing the volumes of CNSL produced each year. Commercialization in other countries is low. Vietnam is capable of producing large quantities of CNSL, given its position as a major sheller. But while interest in CNSL exports, and exports themselves are growing, in 2007 only 21 mt were exported, and in 2008, anecdotal evidence suggests exports were only 600 mt. In total about 65,000 mt of CNSL are produced annually, with commercial sales closely linked to petroleum and petrochemical prices. Tanzania also produces CNSL, but export quantities are small. Trade sources mention Nigeria as an exporter, but there is no hard data to support this. It is traded under tariff heading 13021920 .
CNSL may be a weak promoter of carcinogenesis but no mutagenic or carcinogenic activity has been reported. Epidemiological studies suggested that CNSL may contribute to oral sub-mucous fibrosis. In addition, its phenolic components exerted several biological activities, including antioxidative properties, inhibition of acetylcholinesterase, and membrane perturbation. There is no direct evidence regarding the toxicity of CNSL or its major phenolic components . However, the effluent generated during the processing of the cashew nut could be considered potentially harmful to the environment due to its high phenol content. The hazardous effects of phenolic compounds have been extensively studied. A concentration above 1 mg/1 can affect aquatic life, while recognizes deleterious effects at concentrations as low as 1 pg/ml. As previously mentioned, data on the chemical composition of the cashew nut industry effluent are scarce, but preliminary analysis showed high phenol content due to the cardol, cardanol, and anacardic acid of CNSL. The high toxicity observed for the isolated nols (cardol and cardanol) potentially contribute to the toxicity of the cashew nut industry effluent .
Anacardic acid present in CNSL is the most prominent component responsible for pharmacological activities. It is commonly found in plants of the Anacardiaceae family and is a dietaiy component found in cashew apple (Anacardium occidental) and ginkgo (Ginkgo biloba) leaves and fruits. The traditional Ayurveda depicts nutshell oil as a medicinal remedy for alexeritic, amebicidal, gingivitis, malaria, and syphilitic ulcers. Anacardic acid is found in a number of medicinal plants that have potential activity against cancer cell lines. However, the enduring research and emerging evidence suggests that anacardic acid could be a potent target molecule with bactericide, fungicide, insecticide, anti-termite, and molluscicide properties and as a therapeutic agent in the treatment of the most serious pathophysiological disorders like cancer, oxidative damage, inflammation, and obesity. Moreover, anacardic acid was found to be a common inhibitor of several clinically targeted enzymes such as NFkB kinase, histone acetyltransferase (HATs), lipoxygenase (LOX-1), xanthine oxidase, tyrosinase, and ureases. An interesting observation in this context is its ability to modulate NF-кВ by acting on its upstream pathways. Because NF-кВ is known to be a key player in the progression of human cancers and chronic inflammation, its suppression by anacardic acid indicates a putative potential molecular target of this compound. However, this requires a comprehensive inspection for establishing the scientific rationale for the use of anacardic acid as an anti-cancer and anti-inflammatory agent prior to its use as a novel therapeutic agent for the treatment of human malignancies. Potential of anacardic acids and their semi-synthetic derivatives for antibacterial, antitumor, and antioxidant activities have been reported. The use of anacardic acid as a starting material for the synthesis of diverse biologically active compounds and complexes as well as the natural anacardic acid from CNSL and their semi-synthetic derivatives as lead compounds were reported .
The report has highlighted various chemicals obtainable from CNSL both directly and indirectly. This inexhaustible listing presents CNSL as a very important, reliable source of raw material for petrochemical industry. It is a good, promising supplement and/or alternate to petroleum, which is currently facing depletion globally. Varied CNSL compositions with varying modes of extraction are a vantage opportunity with potential for multiple applications. Though CNSL contains phenolics, its products are highly environmental friendly. However, efficient treatment strategy may be inevitable to reduce environmental impact associated with the production industry.
• biomedical applications • cashew nut shell cashew nut shell liquid