Antioxidant and physicochemical properties of Chrysophyllum albidum fruit at different ripening stages

Chrysophyllum albidum (African Star Apple) fruit is an indigenous African fruit. The African Star Apple plant popularly referred to as the “alasa” tree grows widely in tropical Africa. Ripening influences biochemical processes and subsequently affects the nutritional and bioactive characteristics of the fruits. This study sampled Chrysophyllum albidum fruit of three maturity stages and determined the colour, proximate, total phenol and antioxidant characteristics of the fruits. Spectrophotometric methods were used in the determination of total antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, 2,2-azinobis,3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and Ferric reducing ability of plasma (FRAP) assay. Significant differences (p<0.05) were observed in the colour of the fruit across all the ripening stages. The ripe stage of the fruit recorded the highest extent of lightness among all the other ripening stages. Both the ripe and over-ripe fruits appeared reddish in colour with the ripe fruit demonstrating a higher red intensity than the over-ripe fruit. The calculated metric chroma of the Chrysophyllum albidum fruits were in the range of 2.33-21.67 for the three ripening stages. Hue angle values recorded were in the range 46.46-92.00. Browning and colour indices for fruits of all the stages of development were of range 6.40-80.30 and -14.30-16.96, respectively. Proximate analysis of the three fruit categories showed that the unripe fruits had higher carbohydrate (69.27 %), crude protein (8.17 %), and crude fat (7.99 %) content relative to fruits which were ripe and over-ripe. The over-ripe fruit had higher crude fibre (7.36 %) and ash (3.86 %) content. Total phenolic content for the unripe fruit (20μg GAE/mg) was also higher than fruits of the other ripening stages. The antioxidant ability of the Chrysophyllum albidum fruit showed that the unripe stage recorded the highest DPPH (29.24 %) and ABTS (99.09 %) radical scavenging activity. The ferric reducing antioxidant potential of the fruit at different ripening stages was significantly different (p<0.05) with the unripe stage recording the highest potential. The unripe fruits demonstrated higher proximate and antioxidant composition than the ripe and over-ripe fruits. Extracts from the unripe fruit can serve as useful nutraceuticals in functional food formulations.

Production and Characterization of an Eco-Friendly Oil Based Mud from Synthetic Bio-lubricant Derived from Chrysophyllum Albidum Seed Oil

Sequel to the environmental problems of the none biodegradable nature of the conventional oil-based drilling fluids, it is imperative and urgent for environmental sustainability and for the development of eco-friendly products, that use of petroleum diesel oil as the continuous phase of drilling mud warrant urgent reconsideration. Towards the search to provide a better alternative to petroleum diesel oil as a base oil for drilling mud, vegetable oil from the inedible seeds of the African star apple fruits, was examined In this study, an oil-based drilling mud (OBM) with biodegradable qualities for sustainable environmental applications was developed and characterized. The OBM was produced with chrysophyllum albidum (African star apple) oil methyl ester bio-lubricant to replace petroleum diesel as the continuous phase of the mud. The chrysophyllum albidum oil methyl ester was synthesized from fatty acid methyl ester obtained through transesterification process of none edible oils extracted from chrysophyllum albidum seeds. Tests of physiochemical and rheological properties were carried out on mud samples of chrysophyllum albidum oil biolube-based mud (CAOBBM) and petroleum diesel oil-based mud (PDOBM) to characterise the fluids for performance evaluation and environmental consequences. The findings indicated that CAOBBM was lower in density and less acidic than PDOBM, at barite content of 20 g. Also, CAOBBM had lower viscosity which implies less resistance to flow and lower pressure losses. The low oil to water ratio from the filtration loss test, revealed that CAOBBM is more viable to low fluid loss and consequently enhances wellbore stability and less oil retained on drilled cuttings. Similarly, toxicity test confirmed CAOBBM to be more appropriate and less detrimental to the environment compared to PDOBM. Summarily chrysophyllum albidum oil biolube based muds stands safer and more eco-friendly for a sustainable environment than petroleum diesel oil-based muds.

Production and evaluation of jam produced from plum and African Star apple blends

The potential of some indigenous fruits such as yellow-plum (Spondias mombin) and African Star Apple (Chrysophyllum albidum) remained largely untapped. These fruits can be processed and preserved in small-scale operations using simple techniques that could replace both expensive fruits and the lengthy operation processes usually used for jam production. Blends were produced from African Star Apple and Plum in the following proportion: 100:0%; 90:10%; 80:20%; 70:30%; 60:40% and 50:50% respectively to produce six African Star Apple and plum blends. The chemical properties and consumer acceptability of jams made from these blends were investigated using standard methods. Chemical analyses of the jam showed that vitamin A ranged between 613.09 and 686.04 (IU), sample with the highest percentage of African Star Apple had the highest value of Vitamin A; vitamin C ranged between 30.51 and 46.12 (mg/100 g); pH ranged between 4.29 and 4.58; Brix ranged between 11.00 and 14.97°Bx. There were no significant (p>0.05) differences in the sensory attributes of the samples. It was observed that Jam produced from African Star Apple and plum blend at 50:50% proportion had the highest Vitamin A and those at 90:10% proportion had the highest Vitamin C contents and all the samples were of high nutritional and health benefits.

Proximate and Elemental Analysis of African Star Apple (Chrysophyllum albidum)

The proximate and elemental analysis of African star apple (Chrysophyllum albidum) using standard analytical techniques was investigated. The proximate composition of the plant showed the values of 54.57 % for carbohydrate, 13.25 % of fat, and 3.85 % of crude protein. The crude fiber and ash content indicates the values of 6.60 % and 4.70 % respectively. The moisture content present (17.03 %) reveals the possibility of having low antimicrobial activities of the plant. The mineral elements present in different concentrations are Ca (706.850 mg/kg), Mg (325.500 mg/kg), Fe (40.875 mg/kg), Cu (3.275 mg/kg), and Zn (4.625 mg/kg). The result shows that the fruit have essential minerals required by human for normal life activities. Key words: Chrysophyllum albidum, Star apple, Proximate compositions, Mineral elements

Potentials of African Star Apple (Chrysophyllum albidum) Fruit Shell Adsorbent in Recovery of Valuable Hydrocarbons for Spent Engine Oil

Inventory of spent engine oil continuously increase and indiscriminately disposed of at auto-mechanics garages. Adsorptive separation established to be indispensable in recovery of these hydrocarbons was carried out using Chrysophyllum albidum (African star apple) fruit shell – a renewable resource. In this study, clay pretreated spent engine oil was recovered in a fixed bed adsorption processes and the recovered adsorbate components determined by GC-MS analysis. The results showed African star apple fruit shell adsorbent effective in recovering n-hexane solubilized spent lubricating oil. The study concluded that using the developed African star apple fruit shell adsorbent, an agricultural waste adsorbent in the recovery of waste lubricating oil will enhance greatly the nation’s economy.

In-vitro antimicrobial activity of methanolic and aqueous leaf extracts of Chrysophyllum albidum (African star apple) and Garcinia kola (Bitter kola)

Methanolic and aqueous leaf extracts of Chrysophyllum albidum (African star apple) and Garcinia kola (bitter kola) were studied for in-vitro microbial activity using the disc diffusion technique. The aqueous and methanolic leaf extracts of Chrysophyllum albidum showed antimicrobial activity against Escherichia coli, Staphylococcus aureus and Candida albicans but showed no antibacterial activity against Klebsiella pneumonia. The methanolic leaf extract of Garcinia kola inhibited the growth of Escherichia coli, Staphylococcus aureus and Klebsiella pneumonia while the aqueous extract of the leaf inhibited the growth of Staphylococcus aureus and Escherichia coli. Both methanolic and aqueous leaf extracts of the plant showed no antifungal activity against Candida albicans. The minimum inhibitory concentrations of the leaf extracts of Chrysophyllum albidum ranged from 12.5 mgL-1 to 25 mgL-1 while those of Garcinia kola ranged from 25 mgL-1 to 50 mgL-1. The results obtained suggest that the leaves of these plants can be used in treating diseases caused by the test organisms. The further investigation on the crude extracts would characterize bioactive components of the leaves of Chrysophyllum albidum and Garcinia kola.

Evaluation of differently processed African star apple (Chrysophyllum cainito ) kernel meal as feed for growing rabbits

A 12-week study was carried out to examine the effect of substituting dietary maize with differently processed African star apple kernel meal (ASAKM) on growth performance, blood indices and economic benefits of growing rabbits. A total of 60 weaner rabbits (mixed breed, average weight, 590g) were randomly allocated to five dietary treatments comprising of 10% each of boiled, fermented, roasted and soaked African star apple kernel meal as substitute for dietary maize. Diet 1 (0%ASAKM) served as the control diet. Each of the five treatments was replicated thrice. Each replicate had four rabbits in a Completely Randomized Design. Rabbits fed diets containing 10 % boiled and 10 % roasted ASAKM gained weight (P<0.05) faster than those fed other diets. Feed conversion ratio was significantly better (P<0.05) for rabbits fed BASAKM and RASAKM diets. There were no significant (P>0.05) differences in the blood parameters measured except the white blood cell (WBC), alkaline phosphate(ALP), aspartate amino transferase (AST) and alanine amino transferases (ALT) (P<0.05). Economic analysis showed significant differences (P<0.05) in all the parameters measured. Cost of feed/kg was significantly reduced (P<0.05) with inclusion of ASAKM in rabbit diets. Production cost and revenue (₦) were better (P<0.05) among rabbits fed Boiled ASAKM diet. It was concluded that either BASAKM or Roasted ASAKM can replace 10 % dietary maize in the diets of growing rabbits without compromising growth performance, blood profiles and economic benefits of growing rabbits.

Fermentation Enhanced Biotransformation of Compounds in the Kernel of Chrysophyllum albidum

Chrysophyllum albidum Linn (African star apple) is a fruit with extensive nutritional and medicinal benefits. The fruit and kernel in the seed are both edible. Strains of lactic acid bacteria (LAB) were isolated from fermented seeds and assessed for probiotic characteristics. The extracts in both the unfermented and the fermented aqueous extracts from the kernels obtained from the seeds of C. albidum were subjected to analysis using the gas chromatography/mass spectrometry (GC-MS) method. This analysis identified the bioactive compounds present as possible substrate(s) for the associated organisms inducing the fermentation and the resultant biotransformed products formed. Three potential probiotic LAB strains identified as Lactococcus raffinolactis (ProbtA1), Lactococcus lactis (ProbtA2a), and Pediococcus pentosaceus (ProbtA2b) were isolated from the fermented C. albidum seeds. All strains were non hemolytic, which indicated their safety, Probt (A1, A2a, and A2b) grew in an acidic environment (pH 3.5) during the 48-h incubation time, and all three strains grew in 1% bile, and exhibited good hydrophobicity and auto-aggregation properties. Mucin binding proteins was not detected in any strain, and bile salt hydrolase was detected in all the strains. l-lactic acid (28.57%), norharman (5.07%), formyl 7E-hexadecenoate (1.73%), and indole (1.51%) were the four major constituents of the fermented kernel of the C. albidum, while 2,5-dimethylpyrazine (C1, 1.27%), 3,5-dihydroxy-6-methyl-2,3-dihydropyran-4-one (C2, 2.90%), indole (C3, 1.31%), norharman (C4, 3.01%), and methyl petroselinate (C5, 4.33%) were the five major constituents of the unfermented kernels. The isolated LAB are safe for consumption. The fermenting process metabolized C1, C2, and C5, which are possible starter cultures for the growth of probiotics. Fermentation is an essential tool for bioengineering molecules in foods into safe and health beneficial products.