Use of Theobroma cacao Pod Husk-Derived Biofertilizer is Safe as it Poses neither Ecological nor Human Health Risks

Abstract

Cacao farmers use macerated Theobroma cacao pod husks as biofertilizer for restoration of environmentally important soil elements, i.e., N, P, K, Na, Mg, and Ca. The increasing popularity of this organic material for soil management justifies to experimentally ascertaining that its application does not produce environmental or human health risks. We therefore applied a battery of biological tests to assess possible health risks related to the extract of fermented cacao pod husks [CHE]. Minimal inhibitory concentration for selected bacteria and fungi was established and an antiviral assay (equine herpes virus -EHV-1) and insecticide assay (Aedes aegypti larvae), to observe possible environmental impact. Toxicity tests used Artemia salina, hemolytic activity and cytotoxicity were tested using HT-29 e Vero cells, respectively. Genotoxicity and anti-genotoxic activity was tested in the comet assay of leukocytes and a selection of Saccharomyces cerevisiae mutants allowed look for a possible interference of CHE with defined metabolic pathways. None of these established tests used to define toxicity and genotoxicity of chemical compounds indicated that CHE contained substances that would pose such risks. Our safety assessment on bacteria and yeasts, virus, insect larvae, and human leukocytes [3-(4,5-di-methylazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and comet assay] thus indicated that macerated cocoa pod husk can be safely used as biofertilizer.

Antidiabetic, anti-inflammatory and cytotoxic potential of Theobroma cacao Linn. husk aqueous extracts

“…Data also shows that the TCE samples used in the study are non-toxic since the mortality of brine shrimps did not reach 50% in all concentrations after 24 hours. These results are consistent with the data of Campos Filho et al [28], reporting that the potential damage of T. cacao in leukocyte DNA is relatively low, even in high concentrations. In the study of Santos et al [29], T. cacao husk extracts up to 10 μg/ml concentrations did not cause significant DNA breakage on mammalian cells.…”

Optimization of ultrasound‐assisted pectin recovery from cocoa by‐products using response surface methodology

“…It also contains beneficial compounds like phenolics, flavonoids, and tannins, making it a valuable material for various applications 19 . Cocoa pod husks are used in agriculture for mulching, 20 composting, 21 bioenergy production, 22 and for other industrial purposes. Cocoa pulp mucilage, on the other hand, is rich in sugar content, 23 including glucose, fructose, and sucrose, making it an ideal candidate for natural sweeteners or flavor enhancers in different food products 24 .…”

Acoustic Characterization and Modeling of Silicone-Bonded Cocoa Crop Waste Using a Model Based on the Gaussian Support Vector Machine

“…Cocoa pod husk is an available, abundant, and sustainable resource of bioproducts [17]. The most widespread uses of cocoa pod husk are as fertilizer for the soil [18,19] and as animal feed [20][21][22][23]. Once dry, the cocoa pod husk has approximately 4% potassium, and, taking advantage of this component, the cocoa shell ash allows the production of potassium hydroxide that has been used to make soap [24].…”