*3.1.2.3 Gas chromatography-mass spectrometry (GC-MS)*

*Cheminformatics and Its Applications*

KDM5B were found in many human cancers [29].

*3.1.2.2 Liquid chromatography-mass spectrometry (LC-MS)*

structural characterization of compounds [34].

*3.1.2.1 Mass spectrometry-based method*

analysis of structures [32].

Target-based screening of natural compounds and synthetic chemicals is being considered as a significant innovation for anticancer drug development [28]. In 2007, Lysine demethylase 5B (KDM5B) and Histone demethylase were recognized, which are liable for the removal of H3K4me2/3 activation marker. Thus, for cancer therapy, KDM5B is regarded as a promising drug target, but the elevated levels of

Mass spectrometry is known to be a highly efficient technique for the identification and structural characterization of natural products derived from herbal medicine [31]. Target-based method relies on mass spectrometry to search for active compounds, and this technology can be used for identification, structural characterization, quantitative elemental analysis, tracking of key intermediate compounds in a chemical reaction, analysis of pharmaceuticals and metabolites, and elucidation of unknown structures in drug development. All these achievements can be finally used in various applications like pharmaceutics (drug developments, pharmacokinetics, metabolic pathways), clinical screening, etc. On the basis of MS data information of compounds, the UniFi™ platform has been built for more detailed

LC-MS is an analytical technique for separating different complex mixtures into their components using liquid chromatography. These assays check the correct synthesis, purity, various physical and chemical properties like their volatility and active functionalities present in the newly synthesized chemical entities [33]. During drug discovery, LC-MS hyphenated technique is used for seperation and

*The action potential of phenotypic as well as target-based screening of compounds to validate the hits and leads* 

The respiratory chain of *Streptococcus agalactiae* consists of two enzymes; type 2-NADH dehydrogenase (NDH-2) and cytochrome *bd* oxygen reductase. *S. agalactiae* is considered as the primary cause of sepsis and meningitis in neonates as well as considerable cause of pneumonia and urinary tract infection [30]. The difference between phenotypic and target-based screening is shown in **Figure 3**. Some of the target-based screening methods are mentioned as follows.

*3.1.2 Target-based screening*

**132**

**Figure 3.**

*from natural and synthetic compounds.*

GC-MS is another hyphenated technique for the identification and structure elucidation of unknown compounds derived from natural products [35]. For example, by using GC-MS technique, comprising a gas chromatograph (GC) coupled to a mass spectrometer (MS), complex components of natural oils mixtures may be separated, identified, and quantified, e.g., oils extracted from Apiaceae family (*Anethum graveolens*, *Carum carvi*, *Cuminum cyminum*, *Coriandrum sativum*, *Pimpinella anisum*, *Daucus carota*, *Apium graveolens*, *Foeniculum vulgare*, and *Ammi visnaga*). As a result of this separation technique, petroselinic acid was the major fatty acid from all other palmitic, palmitoleic, stearic, petroselinic, linoleic, linolinic, and arachidic acids [36].
