Welcome to National Botanical Research Institute: NBRI Lucknow

R & D Area > Biotechnology & Plant Physiology

Plant Metabolism & Biochemistry

Group Leader	Dr. (Mrs.) S. Kochhar, Sci 'EII'
Contact	Work	91-522- 2205831-35 Ext. 315
Contact	Home	91-522- 2397202

Group works on

Characterization of novel hyperthermophilic proteins from plants and their use in pharmaceutical, nutraceutical and comaceutical products.
Protein enrichment of crop plants for nutritional improvement with reference to biosynthesis of essential amino acids such as lysine, threonine and methionine including the use of protein rich cyanobacteria and their pathways for crop improvement.
Mechanism of thermo tolerance in plants. We are studying the effects of heat shock and expression of heat shock proteins that may be synthesized as a result of sensitivity of plants to high and low temperatures and multiple stresses (salinity, heavy metals), signal transduction pathways, oxidative defense enzymes in stress tolerance. Studies on photoreceptors involved in light effects especially in relation to nitrogen assimilation and pigment biosynthesis.
Effects of heavy metals stresses of algae, cyanobacteria and higher plants metabolisms, stress induced changes in anti-oxidative defense enzymes nitrogen assimilation enzymes, signal transduction pathways and induction of new proteins synthesized as result of heavy metals including metallothianins and metal binding proteins.
Post harvest physiology of fruits such as apples, mangoes, bananas and guavas.

Major Achievements of the Group

(1) Novel and stable enzymatic antioxidant and health and body care products in pipeline using the enzymatic antioxidant system at NBRI

In this age of proteomics and genomics therapy the proteomic therapy will be mainly based on enzymes. We are happy to announce the discovery of some highly stable natural antioxidant enzymes which are stable at very high temperatures of even up to 100 ºC. These enzymes have immense applications in cosmecuticals, nutraceuticals and medicines. . Needless to mention that during normal metabolism our body produces reactive oxygen species called free radicals, which are generally produced as a result of partial reduction of molecular oxygen. The production of free radicals is stimulated under stressful conditions and cause oxidative damage and degenerative changes such as “ageing”. Free radicals have also been implicated in cancer, arthritis and inflammatory disorders, diabetes, cataract ogenesis, amyotrophic lateral sclerosis (ALS), AIDS and even in nervous disorders such as Parkinson’s disease and Alzheimer’s disease. The free radicals are scavenged/removed by the antioxidant defenses which can be non -enzymatic or enzymatic in nature.

We have discovered a novel and stable enzymatic antioxidant system consisting of superoxide dismutase and peroxidase enzymes from selected plants. The enzymatic antioxidant is heat stable, autoclavable with only negligible loss in enzymatic activity under extremely harsh conditions and is more than hundred times faster in its action.

The stable enzymatic antioxidant system has been fully purified and characterized and a patent has been filed in India, USA and PCT Global patent (WO 2005/017134). Besides free radical scavenging activity the enzyme system exhibits anti-bacterial, anti-inflammatory, anti-fungal and health protective properties. This enzymatic antioxidant detoxifies the cells and restores their ability to reproduce and remain “young”.

The extra ordinary properties of the enzymatic antioxidant make it a unique tool in the development of new enzymatic protein-based products for the first time for use in health and cosmetic industries.

The products developed by us reduce wrinkles, reduce scars, heal wounds reduce hyper pigmentation, strengthen hair roots and reduce hair loss.

Because of their efficiency and effectiveness, only small quantities of these products are needed.

Products

Enzyme based instant glow face pack for teen-agers –Enzymatic antioxidants in the face pack makes your skin vibrant and fresh.
Enzyme based anti-ageing cream for wrinkle-free, younger looking healthy skin – Invigorates the old dying cells of your precious skin.
Enzyme based lip balm: gives great protection to your lips from cracking and sores, gives a smooth and fresh look to your lips with anti ageing properties.
Enzyme based anti-inflammatory and anti psoriatic cream- gives you instant relief against inflammation and itching and prevents the built of dead cells by reducing the turnover of cells in a psoriatic skin.
Enzyme based anti ageing face pack for normal skin - Invigorates the naturally old dying cells and adds an instant glamour to your skin.
Enzyme based anti ageing face pack for oily skin- reduces the extra oil produced by dermis cells and gives a fresh, bright and cleaner look to your skin.
Enzyme based instant glow face pack for acne-prone skin.
Enzyme based antibacterial, anti-inflammatory toothpicks for healthier gums – can use safely as tooth pick even in unhealthy gums.
Enzyme based hair tonics and shampoos for controlling hair fall and graying- this hair tonic gives you fast relief in hair fall, strengths your hair roots and prevents graying.
Enzyme based facial scrubs – these are bursting with natural vitamins A, C, E along with aloe Vera.

Enzyme based products developed at NBRI

(2) Nutritional improvement of through biochemical and molecular biology techniques:

Aspartate is the precursor for the biosynthesis of three of the most important essential amino acids namely lysine, threonine and methionine that are required for the growth of non-ruminant animals and humans. As these organisms cannot synthesize these amino acids, these have to be obtained from the diet. Most of our crop plants are deficient in one or more of amino acids. While cereals are deficient in lysine and threonine, the legume crops like pulses are deficient in sulphur amino acids such as methionine. Work has been going on in this laboratory to understand the pathways of biosynthesis of lysine, threonine and methionine in plants and cyanobacteria in order to manipulate these pathways to advantage. Our group is one of the 2-3 groups working on these essential amino acids from plants all over the world. It has been found that first enzyme of the pathway- asparatate kinase exerts a regulatory influence on the pathway. This enzyme has been purified and characterized fully by us and its regulation has been studied.

Some of the important results are:

AK occurs as 2-3 isoenzymes sensitive to lysine, threonine/adenocyl methionine.
AK is regulated by calcium and calmodulin and a calmodulin like calcium-binding protein is a subunit of the enzyme.
The enzyme is also regulated by light with choroplastic and cytosolic isoforms and the light regulation occurs through phytochrome the red-far-red absorbing photoreceptor. The light also controls the expression of asparate kinase/homoserine dehydrogenase (akhsd) gene.
The gene for asparate kinase/homoserine dehydrogenase has been cloned and sequenced from the cyanobacteria.
Some mutants of cyanobacteria with modified capacity to synthesize lysine, threonine and methionine have been developed. The genes from these mutants are being characterized for transferring to other crops for nutritional improvement.
Characterization of other enzymes of aspartate pathway is being undertaken. Recently, we have characterized and purified DHPS from cyanobacteria.

(3) Physiological and biochemical characterization of thermo tolerance in plants:

Vigna radiata (Mungbean), Amaranthus caudatus and Curcuma are being studied. While a continuous growth of seeds at 40^o C was deleterious for germination and early growth of seedlings of Mungbean; heat shock for shorter duration (1-2 hrs) in fact promoted germination and early seedlings growth. This is irrespective of other stress factors like mild heavy metal toxicity (Cd⁺⁺). However, at higher heavy metal toxicity levels, the metal toxicity pre dominated the heat effect and this resulted in growth inhibition. Longer durations of heat treatments also resulted in deleterious effects. The activity of peroxidase (POD) increased considerably with heat shock and continuous treatment at high temperature, that of superoxide dismutae (SOD) decreased with heat and heat shock. This increase in POD activity quenches the peroxide radicals. The immunological studies of the status of heat shock proteins showed that the high molecular weight HSP 70 did not change with heat or heat shock but the lower molecular weight HSP 18.1 was induced as a result of heat shock or was intensified with heat treatments.

Recent results obtained this year show that Vigna radiata seedlings exhibit 3 SOD isoenzymes with molecular masses of 45, 27 and 18 kDa. One of them (45 kDa) is MnSOD while the other two are C/ZnSOD. With heating and heat shock one of the Cu/Zn (18 kDa) is inhibited completely and the other two are inhibited partially. A novel heat stable and autoclavable antioxidant system has also been isolated from some plants. The quantity of this varies with plant species.

Different peroxidases (molecular mass 160-80 kDa) are involved in germination and in further development. The peroxidases with lower molecular masses (45-10 kDa) make their appearance after 48 hours. Peroxidases and catalase increases both with heat shock and heat stress and also with Cd⁺⁺ application.

(4) Improvement of floriculture and post harvest physiology:

Bougainvilleas: Bougainvilleas have multi-colored bracts from white to magenta, red, violet, yellow and so on. This gives the plant the name of Glory of Gardens. We have used bract color as a chemotaxonomic marker for the identification of different cultivars. More than 100 cultivars were identified and classified by this method. Different holding solutions have been developed for using Bougainvillea as cut flower.

Betel vine: Agro-techniques have been developed for growing betel vine used for its leaves which are used for chewing with various conditions all over South Asia and south east Asia. Post harvest packages practices have also been developed for its long-term storage and transportation.

Post-harvest Physiology of fruits: IMCP, an ethylene antagonist was found to increase the shelf life of Guava (Lucknow-49 variety) and Indian Sweet Red Apple. Activities and isoenzyme patterns of antioxidant enzymes of these fruits with IMCP treatment have also been studied with interesting results.