P C Jain’s research while affiliated with Dr. Hari Singh Gour University and other places

Various carbon sources were evaluated for production of inulinase by yeast, Kluyveromyces marxianus MTCC 3995. Highest inulinase activity was observed with Dahlia extract (25.3 nkat mL(-1)) as carbon source. The enzyme activity was 1.4 folds higher than that observed in media containing pure chicory inulin (17.8 nkat mL(-1)). The yeast showed good growth on a simple medium containing dahlia extract (20% w/v) and yeast extract (2%w/v) as carbon and nitrogen source respectively, in 96 h. at 28°C and 120 rpm. Lowest inulinase yield (4.8 nkat mL(-1)) was seen in the medium containing glucose as C-source. Although varied inulinase levels were noticed on different C- sources, Inulinase: Sucrase (I/S) ratios were noticed to be similar. Among various protein sources tested, yeast extract was found to be the best source followed by beef extract (17.9 nkat mL(-1)) and peptone (13.8 nkat mL(-1)). The enzyme was optimally active at pH (4.0) and 50°C. TLC analysis of end product revealed that inulinase hydrolyzed inulin exclusively into fructose. Results suggest that the dahlia extract induced exoinulinase synthesis in Kluyveromyces marxianus and can be utilized as a potential substrate for inulinase production.

Several million tonnes of feather are produced annually as a byproduct of poultry processing industries and poultry farms which apart from polluting soil and water also plays important role in spread of various human ailments such as dermatophytic infections, chlorosis, mycoplasma fowl cholera and avian influenza. Feather waste being rich in keratin protein are difficult to degrade as the polypeptide are densely packed and stabilized with numerous hydrogen bonds, disulphide bonds and hydrophobic interactions. Despite of recalcitrant nature of keratin proteins, keratin waste do not accumulate in nature confirming the presence of natural decomposers. A number of dermatophytes, saprophytic fungi, bacteria and actinomycetes are known to degrade keratin by virtue of a particular class of endoproteases called keratinase(s) that display the capability to degrade structure conforming keratin protein. Feathers are composed of approximately 90% keratin protein thus can be a potential source of proteins and amino acids. Application of keratin degrading microorganism have provided appropriate technology for bioconversion of poultry feather into nutritionally enriched feed stuffs and essential amino acids. Waste feathers have also been used as substrate for production of proteolytic enzymes including keratinases. Enzymes produced by keratinolytic microorganisms have also find applications in prion degradation and peptide synthesis. Recent researches on utilization of feather waste are on the way to develop low cost hydrogen storage system from carbonized chicken feather fiber. The conventional methods employing incineration or chemical transformation of feather usually resulting in production of low grade feather meal thus the methods appear to be inadequate. In continuation of these developments, a new improved process has been suggested for obtaining biodiesel fuel in addition to the production of feather meal from chicken feathers. However, biotransformation process can be further improved by involving certain steps of biofuel production to make the process cost effective for the production of high grade feather meal from waste feather.

A keratinolytic bacterium Elizabethkingia meningoseptica KB042 was isolated from dropped off feathers. The bacterium showed 82.50 ± 0.3% feather degradation when grown on medium containing 10 g/l chicken feathers with initial pH 7.0 at 37°C, 150 rpm in 6 days. The pH of the medium was increased up to 10.02 ± 0.10 during 6 days of incubation. Soluble protein and amino acids concentration in the culture fluid was also found increased until the end of incubation. During the cultivation of strain KB042 on feather as sole source of carbon and nitrogen, the maximum cysteine release was noted on the 3rd day. Varying feather concentration 1.0-2.0% in basal medium resulted in soluble protein release between 1814.42 and 1954.61 μg/ml. The amino acid concentration was found to be maximum, i.e. 937.85 ± 11.9 μg/ml in the cultures grown with 2% feather. The hydrolysate was also found rich in essential amino acids valine, tryptophan, threonine, leucine and cysteine and contains minor amount of methionine and arginine. These data indicate a potential biotechnology for biotransformation and utilization of feather keratin as a source of protein which can be used as animal feed after successful animal trials.

Feather waste is generated in large amounts as a by-product of commercial poultry processing. This residue is almost pure keratin, which is not easily degradable by common proteolytic enzymes. Eight strains of Bacillus, isolated from decomposing feathers were tested for the hydrolysis of feather wastes in the laboratory. Among these strains, Bacillus cereus KB043 was the best feather degrading organism when grown on basal medium containing 1% hen feather as sole source of carbon and nitrogen. It caused 78.16 ± 0.4 % degradation with a significant release of soluble protein (1206.15 ± 14.7 µg mL(-1)) and cysteine (20.63 ± 0.4 µg mL(-1)) in the cultivation fluid. The strain also showed the highest level of keratinase activity (39.10 ± 0.4 U mL(-1)). These data indicates that the Bacillus cereus KB043 could be useful in management of poultry wastes.

Streptomyces exfoliatus CFS 1068, an isolate of cultivated field soil, produced maximum collagenase activity (58.19 +/- 0.83 U ml-1 min-1) in 5 days when soybean meal and starch were used as nitrogen and carbon sources, respectively at pH 7 and 30 degrees C in shake cultures (150 rpm). Production of collagenase was higher (40.43 +/- 0.63 U ml(-1) min(-1)) when poultry feathers were used as nitrogen source. Thus, the strain was found to be of biotechnological importance. The purified enzyme showed 30.34 fold increase in collagenase activity and was stable at 70 degrees C for 1h. The enzyme was found to be of serine type.

Feathers from 4 different birds were taken as substrate to find out the role of natural fatty material during the process of saprophytic colonization by some keratinophilic fungi. In the present investigation three fungi i.e., Keratinophyton terreum, Microsporum gypseum and Malbranchea aurantiaca were taken as test fungi. It is concluded that the presence of natural fatty materials on feathers have inhibitory effect on their colonization by some of the test organisms. Zusammenfassung: Für die Prüfung, welche Rolle das natürliche Fettmaterial an Federn für die saprophytische Besiedlung durch keratinophile Pilze spielt, wurden Federn von 4 verschiedenen Vogelarten untersucht. Als Pilze wurden eingesetzt: Keratinophyton terreum, Microsporum gypseum und Malbranchea aurantiaca. Es wird der Schluß gezogen, daß die Gegenwart von natürlichen Fetten auf den Federn einen Hemmeffekt auf einige der Testpilze hat.

A new keratinophilic species, Chrysosporium gourii, an isolate of cattle farm soil of Sagar, India, is described and illustrated. The differences between this and other similar keratinophilic species of Chrysosporium are discussed. Zusammenfassung. Es wird eine neue keratinophile Pilzart, Chrysosporium gourii, ein Isolat aus dem Erdboden einer Rinderfarm in Sagar, Indien, beschrieben und illustriert. Die Unterschiede zwischen dieser und ähnlichen keratinophilen Chrysosporium- Arten werden diskutiert.

Thermophilic Thermomyces lanuginosus NK-2, isolated from wheat straw compost, produced 1418 IU mL<sup>-1</SUP> of thermostable xylanase (EC 3.2.1.8) on Czapek`s basal medium containing wheat bran (2% w/v). The specific activity of NK-2 xylanase was found to be 1107 IU mg<sup>-1</SUP> of total protein. The fungus could also utilize different  low-value  agricultural  residues  and  produce  xylanase  on  corncobs  (1004 IU mL<sup>-1</SUP>), lentil bran (941 IU mL<sup>-1</SUP>) and groundnut shells (355 IU mL<sup>-1</SUP>). Supplementation of pure xylan (1% w/v) to wheat bran medium enhanced xylanase yield by 39% while other C-supplements repressed it. The xylanase was found to be active over a broad pH (4.0-9.0) and temperature range (25-85°C) and the pH and temperature optima were 5.0 and 6°C, respectively. It showed excellent thermal stability by retaining 83.4% activity after one hour of incubation at 6°C and its half-life at 7°C was 40 min. Presence of β-xylosidase (0.007 IU mg<sup>-1</SUP>) was also noticed while CMCase and α-L-arabinosidase were not detected.