In Ancient Egypt, according to archaeology as well as the account provided in the book of Exodus chapter 5, straw was mixed with mud in order to produce building bricks. Modern investigations have found that the humic acid is released from straw when the straw is mixed with mud and that this strengthens the material, which produces stronger bricks that are less likely to break or lose their shape

Since the end of the 18th century, humic substances have been designated as humic acid, fulvic acid or humin. These fractions are defined strictly on their solubility in either acid or alkali, describing the materials by operation only, thus imparting little chemical information about the extracted materials. The term ‘humic substances’ is used in a generic sense to distinguish the naturally occurring material from the chemical extractions named humic acid and fulvic acid, which are defined “operationally” by their solubility in alkali or acid solutions. It is important to note, however, that no sharp divisions exist between humic acids, fulvic acids and humins.

The Fulvic acid,with the CAS registry number is 479-66-3. The IUPAC name is 3,7,8-trihydroxy-3-methyl-10-oxo-1,4-dihydropyrano[4,3-b]chromene-9-carboxylic acid. In addition, the molecular formula is C₁₄H₁₂O₈ and the molecular weight is 308.24. It is commonly used as a soil supplement in agriculture, and less commonly as a human nutritional supplement. And it can be extracted as a colloidal sol from soil and other solid phase sources into a strongly basic aqueous solution of sodium hydroxide or potassium hydroxide.

Physical properties about Fulvic acid are:
(1)ACD/LogP: 1.46; (2)ACD/LogD (pH 5.5): -1.68; (3)ACD/LogD (pH 7.4): -1.86; (4)ACD/BCF (pH 5.5): 1; (5)ACD/BCF (pH 7.4): 1; (6)ACD/KOC (pH 5.5): 1; (7)ACD/KOC (pH 7.4): 1; (8)#H bond acceptors: 8; (9)#H bond donors: 4; (10)#Freely Rotating Bonds: 4; (11)Polar Surface Area: 89.52 Å²; (12)Index of Refraction: 1.736; (13)Molar Refractivity: 69 cm³; (14)Molar Volume: 171.6 cm³; (15)Polarizability: 27.35 ×10^-24cm³; (16)Surface Tension: 108 dyne/cm; (17)Density: 1.79 g/cm³; (18)Flash Point: 255.1 °C; (19)Enthalpy of Vaporization: 102.18 kJ/mol; (20)Boiling Point: 661 °C at 760 mmHg; (21)Vapour Pressure: 2.27E-18 mmHg at 25°C.

You can still convert the following datas into molecular structure:
(1)SMILES: O=C(O)c2c1C(=O)\C3=C(/Oc1cc(O)c2O)CC(O)(OC3)C
(2)InChI: InChI=1/C14H12O8/c1-14(20)3-8-5(4-21-14)11(16)9-7(22-8)2-6(15)12(17)10(9)13(18)19/h2,15,17,20H,3-4H2,1H3,(H,18,19)
(3)InChIKey: FCYKAQOGGFGCMD-UHFFFAOYAO