Fibrous Agricultural Biomass as a Potential Source for Bioconversion to Vanillic Acid

Table 4

Total nonferulate phenolic compounds (NFPC) and percentage of ferulic acid (FA) content in total phenolic compounds (TPC) in lignin-free liquor produced from six different biomasses through alkaline and organosolv treatment at 120°C for an hour (; ).

Biomass	TPC (mg GAE g^−1 biomass; d.b.)		NFPC (mg GAE g^−1 biomass; d.b.)		% FA of TPC
	Organosolv treatment	Alkaline treatment	Organosolv treatment	Alkaline treatment	Organosolv treatment	Alkaline treatment
EFB	9.44 ± 0.70^bA	8.94 ± 0.13^bA	7.60 ± 0.74^bA	7.12 ± 0.10^bA	19.62 ± 1.90^dA	20.39 ± 0.10^dA
CCF	47.99 ± 4.13^eA	27.169 ± 2.65^dB	46.29 ± 4.14^eA	25.47 ± 2.65^dB	3.57 ± 0.31^aB	6.30 ± 0.65^aA
PP	27.17 ± 1.90^dA	20.73 ± 0.53^cB	24.63 ± 1.87^dA	18.39 ± 0.60^cB	9.38 ± 0.57^bB	11.29 ± 0.84^bA
PCL	21.78 ± 0.80^cA	18.23 ± 2.23^cB	18.31 ± 3.01^cA	16.50 ± 2.30^cA	8.89 ± 1.54^bA	9.59 ± 1.51^bA
KBF	5.56 ± 0.35^aA	3.61 ± 0.09^aB	3.86 ± 0.37^aA	1.92 ± 0.08^aB	30.63 ± 2.19^eB	67.34 ± 0.92^eA
KCF	8.19 ± 0.69^bA	7.04 ± 0.13^bA	7.13 ± 0.68^bA	5.99 ± 0.14^bB	12.96 ± 1.00^cB	14.93 ± 0.43^cA

(a) EFBF: palm oil empty fruit bunch fiber; CCF: coconut coir fiber; PP: pineapple peel; PCL: pineapple crown leaves; KBF: kenaf bast fiber; KCF: kenaf core fiber.
(b) GAE represents gallic acid equivalent.
(c) a–e: different alphabets in the same column represent that there are significant differences between the mean values of the different biomasses ().
(d) A-B: different alphabets in the same row represent that there are significant differences between the mean values of the different treatments ().