( He ( also ( ( discovered ( ( lysozyme , ) ( ( an ( antibacterial agent ) ) ( in ( ( tears and ) saliva ) ) ) ) ) . ) ) )
(ROOT (S (NP (PRP He)) (ADVP (RB also)) (VP (VBD discovered) (NP (NP (NN lysozyme)) (, ,) (NP (NP (DT an) (JJ antibacterial) (NN agent)) (PP (IN in) (NP (NNS tears) (CC and) (NN saliva)))))) (. .)))
He also discovered lysozyme, an antibacterial agent in tears and saliva.
(ROOT (S (NP (NNP Human) (NNP lysozyme)) (VP (VBZ is) (NP (NP (DT an) (JJ antibacterial) (NN protein)) (VP (VBN found) (PP (IN in) (NP (NNS tears) (CC and) (NN saliva)))))) (. .)))