DETERMINATION AND QUANTIFICATION OF SINIGRIN GLUCOSINOLATES IN ALTERNARIA
SOLANI SUSCEPTIBLE TOMATO ( SOLANUM LYCOPERSICUM ) LEAVES TREATED WITH
MORINGA ( MORINGA OLEIFERA ) LEAF E…

DETERMINATION AND QUANTIFICATION OF SINIGRIN GLUCOSINOLATES IN ALTERNARIA
SOLANI SUSCEPTIBLE TOMATO ( SOLANUM LYCOPERSICUM ) LEAVES TREATED WITH
MORINGA ( MORINGA OLEIFERA ) LEAF E…

CULVER MVUMI

ELIZABETH NGADZE

DIANA MARAIS

ELSA S. DUTOIT

JAMESON KUGARA

The study investigates the presence and quantity of anti-
microbial sinigrin glucosinolates in tomato leaves after
spraying them with moringa (Moringa oleifera) leaf extract
(MLAE). Moringa concentrates (0.5, 0.75, 1.00 and 1.5 kg L
1
(w v
1
)) were prepared. Distilled water was the control.
Sampled tomato leaves were air-dried, freeze-dried and
extracted firstly using pure methanol in a hot water bath
and then pellet re-extracted using 5 mL of hot aqueous
methanol (70% v v
1 ). An ion exchange column, and sul-
phatase was used to achieve glucosiodesulphonation. High
performance liquid chromatography (HPLC) was employed
in the identification and quantitative analysis of the sinigrin
glucosinolates. Tomato (Solanum lycopersicum) leaves
treated with MLAE revealed highly significant (p < .001) con-
tent of sinigrin glucosinolates. The sinigrin standard and the
desulphated sinigrin glucosinolates had a 7 s retention time
difference; 5 kg L
1 (w v
1
) resulted in a superior amount of
sinigrin in tomato leaves as compared to all the other MLAE
concentrations. The study reveals that spraying MLAE on
putatively diseased tomato leaves donates specific quantifi-
able glucosinolates like sinigrin, which may be involved in
defense against tomato diseases and, hence, recommends
use of 5 kg L
1 (w v
1
) for the highest sinigrin defense tag.

Archives of Phytopathology and Plant Protection

2018