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In this study, the oven drying behaviour, as well as changes in the morphological appearance of Vernonia amygdalina leaves before and after drying were investigated. The drying experiments were conducted using a universal oven. Vernonia amygdalina leaves were dried at 40, 50 and 60 °C air temperatures. During the drying processes, the air flow rate was held at 1 m/s2 and the samples spread on the drying trays were placed parallel to the direction of air flow. The obtained data were fitted to eleven different mathematical drying models. Four statistical tools, viz, correlation coefficient, mean bias error, sum of the square error, and reduced chi-square were used to analyse the fittings. Amongst the considered drying models, Midilli-Kucuk drying model showed the best fitting in describing the drying behaviour of Vernonia amygdalina leaves. In addition, the effective diffusivities for the three air temperatures ranged from 4.55 × 10−12 to 5.48 × 10−12 m2/s with the activation energy of 8.048 kJ/mol. Moreover, to evaluate the effect of drying conditions on the morphological changes of Vernonia amygdalina leaves, fresh and dried leaves under different conditions were compared. Thus, drying conditions had effects on microstructure of Vernonia amygdalina leaves. Keywords: Drying, Mathematical models, Morphology, Vernonia amygdalina

Carica papaya is a well-known plant with diverse importance to human beings. The efficacy of microwave-assisted extraction (MAE) in the recovery of phenolic compounds from C. papaya leaf was investigated in this study. The MAE process variables were optimized using response surface method; at the optimized conditions, the embedded phenolic compounds in the extract were identified through LC-QTOF-MS analysis. The results showed that the best MAE conditions were: time of irradiation at 3 min; microwave power of 420 W; feed-to-solvent ratio of 1:12 g/mL; and solvent concentration of 56% ethanol/water to achieve 102.59 mg GAE/g d.w. of total phenolic content (TPC). At these conditions, an aggregate of 72 phenolic compounds was tentatively identified. These results infer that MAE as a technique can recover phenolic compounds from C. papaya leaf. Hence, the identified compounds can further be quantified with their respective pharmacological properties in future studies.

The free radicals are reactive molecules that emanate during oxidation; this can then stimulate a chain reaction that can cause cellular damage. A lot of studies had affirmed the implications of free radicals mostly the reactive oxygen species in generating over a hundred degenerative diseases in the human being; these include cancer, acquired immunodeficiency syndrome (AIDS), diabetes, central nervous system injury, arthritis, gastritis, atherosclerosis, reperfusion, and ischemia injury of different tissues. Scientific studies have postulated that the bioactive compounds mainly from natural products can protect the body system from free radicals. Thus, this chapter focuses on the antioxidant potential of Vernonia amygdalina and its toxicology.

The tentative identification of bioactive compounds in the extract of Vernonia amygdalina leaf was carried out using positive ionization of Liquid chromatography-mass spectrometry quadrupole time of flight (LC-Q-TOF/MS). The positive ionization is associated with the presence of saponins, flavonoids, alkaloids, terpenoids, and glycosides. Tentative assignments of the secondary metabolites were performed by comparing the MS fragmentation patterns with Waters® UNIFY library which allows positive identification of the compounds based on the spectral match. All the metabolites compounds were estimated and presented in a BPI (Base peak intensity) plot. These data are the unpublished supplementary materials related to “Ethanolic extraction of bioactive compounds from V. amygdalina leaf using response surface methodology as an optimization tool” (Alara et al., 2018).

This paper contains data from the elemental and phytochemical profiling of black pepper oleoresin extracts using the LC-MS QToF and ICP-MS analysis. In recent years studies have shown the medicinal properties of extracts from these two cultivars of Piper nigrum. The medicinal properties are attributed to the presence of many secondary metabolites and mineral element in them. The phytochemical profiling was conducted using a Liquid Chromatography equipped with an electrospray time-of-flight mass spectrometer detectors. The mass spectrometer was equipped with an electrospray ionization sources operated in positive ion mode. The alkaloid compounds in the optimized black pepper extract were tentatively characterized in accordance with their ions׳ mass fragmentation.

Biosurfactants are amphiphilic compounds synthesized from plants and microorganisms. These compounds are well known to be promising alternative molecules for industrial and domestic applications due to their high biodegradability, low toxicity, multi-functionality, environmental capability, and availability of resources. In recent times, the chemical compounds of biosurfactants have gained much attention because they are considered as a suitable alternative and eco-friendly materials for remediation technology. The current society is facing several challenges of implementation, enforcing environmental protection and climate change for the next generations. Thus, studies on human and environmental safety to improve the efficiency of sustainable technologies on environmental remediation are being investigated. Biosurfactants exhibited an efficient and successful application in various industries such as cosmetic, pharmaceutical, food, petroleum, agricultural, textile, and wastewater treatment. In this regard, this review focused on the advantages of biosurfactants over the synthetic surfactants produced from petroleum-based products along with their potential application in different industries. Keywords: Biosurfactant, Contaminated soil, Heavy metal, Skin care, Enhanced oil recovery