Element

Lukuyu et al., 2014

Jorgetto et al., 2014

Present study (2021)

Samples location

Local market,

Ibadan city,

Oyo, Nigeria

Conventional market,

Botucatu city,

Sao Paulo, Brazil

Markham, Morobe,

Papua New Guinea

Continent

Africa

South America

Oceania (South Pacific)

Carbon (%)

Not reported

41.42

40.25

Hydrogen (%)

Not reported

6.64

5.76

Nitrogen (%)

Not reported

1.02

0.77

Sulphur (%)

0.22

0.60

0.01

Phosphorus (%)

0.14

Not reported

0.03

{100 − [C + H + N + S + P]}%

(oxygen, minerals, etc.)

--

50.32

53.18