The content of chlorophylls can be determined photometrically following extraction of the pigments using an
organic solvent, such as acetone or dimethyl formamide, or else by means of handheld device based on lightemitting
diodes and silicon photodiode receptor that measures leaf transmittance in the red (650 nm) and infrared
(950 nm) regions of the electromagnetic spectrum5. The transmittance values are used by the device to derive a
relative SPAD meter values that is proportional to the amount of chlorophyll in the sample. The former method is
considered as in vitro measurement which is well established and accurate, but time-consuming, destructive, and
requires the use of toxic or flammable chemicals. On the other hand, the latter provides an alternative in vivo
method for the measurements of relative leaf chlorophyll levels that overcome these disadvantages, but it is less
accurate, not applicable for small or thick leaf, influenced by light condition, and produces only predictive value.
There have been numerous studies which evaluated the correlation between in vitro chlorophyll data with its in
vivo data, based on SPAD value as well percentage of nitrogen in leaf, by using available handheld instruments. The
correlation between SPAD value and % N was mostly found as strong linear function, while the strong relationship
(R2 ~ 0.9) between SPAD value and in vitro chlorophyll concentration has been previously proposed to follow
exponential6 or second-order polynomial function5,7. Most of the studies employed the leaves of growing plant at
certain medium or light set up, but there are only a few numbers of investigations which employed post-harvested
samples. Here, the correlation between in vivo and in vitro data of the chlorophyll content of ten green leafy
vegetables purchased from three different supermarkets at Malang, East Java, Indonesia, was observed. The
objectives of this study were to (i) identify the range of the SPAD value and % N for ten selected green leafy
vegetables ontheir condition in the market; and (ii) find out the distribution of the feasibility of in vivo
measurement among ten selected leafy vegetables, compared to their in vitro data.